Merge remote-tracking branch 'upstream/master'

index.html

@@ -40,6 +40,7 @@
         </nav>
     </header>
     <main id="splash">
+        <div class="drag-overlay"></div>
         <header>
             <h1><img src="og-preview.png" alt="">Lexy's Labyrinth</h1>
         </header>
@@ -58,21 +59,20 @@
 
         <section id="splash-upload-levels">
             <h2>Other levels</h2>
-            <p>You can play <code>CHIPS.DAT</code> from the original Microsoft version, any custom levels you have lying around, or perhaps ones you found on the <a href="https://sets.bitbusters.club/">Bit Busters Club set list</a>!</p>
+            <p>Load and play any levels you have on hand — both the original levels and any custom ones, perhaps ones you found on the <a href="https://sets.bitbusters.club/">Bit Busters Club set list</a>.  Supports CCL/DAT, C2G, and individual C2Ms (though scores aren't saved for those).</p>
-            <!-- TODO explain how to find chips.dat or steam folder -->
+            <!-- TODO zip files! -->
-            <!-- TODO drag and drop? -->
+            <p>You can also drag and drop files or directories into this window.</p>
-            <input id="splash-upload" type="file" accept=".dat,.ccl,.c2m,.ccs">
+            <input id="splash-upload-file" type="file" accept=".dat,.ccl,.c2m,.ccs" multiple>
-            <button type="button" id="splash-upload-button" class="button-big">Open a local level<!-- TODO: <br>(or drag and drop a file into this window) --></button>
+            <input id="splash-upload-dir" type="file" webkitdirectory>
-            <p>Supports both the old Microsoft <code>CHIPS.DAT</code> format and the Steam <code>C2M</code> format.</p>
+            <button type="button" id="splash-upload-file-button" class="button-big">Load files</button>
-            <p>Does <em>not</em> yet support the Steam <code>C2G</code> format, so tragically, the original Steam levels can only be played one at a time.  This should be fixed soon!</p>
+            <button type="button" id="splash-upload-dir-button" class="button-big">Load directory</button>
-            <!--
+            <p>If you still have the original Microsoft "BOWEP" game lying around, you can play the Chip's Challenge 1 levels by loading <code>CHIPS.DAT</code>.</p>
             <p>If you own the Steam versions of <a href="https://store.steampowered.com/app/346850/Chips_Challenge_1/">Chip's Challenge 1</a> (<em>free!</em>) or <a href="https://store.steampowered.com/app/348300/Chips_Challenge_2/">Chip's Challenge 2</a> ($5 last I checked), you can play those too, even on Linux or Mac:</p>
             <ol class="normal-list">
                 <li>Right-click the game in Steam and choose <em>Properties</em>.  On the <em>Local Files</em> tab, click <em>Browse local files</em>.</li>
                 <li>Open the <code>data</code> folder, then <code>games</code>.</li>
-                <li>You should see either a <code>cc1</code> or <code>cc2</code> folder.  Drag it into this window.</li>
+                <li>You should see either a <code>cc1</code> or <code>cc2</code> folder.  Drag it into this window, or load it with the button above.</li>
             </ol>
-            -->
         </section>
 
         <section id="splash-your-levels">

js/format-base.js

@@ -1,6 +1,4 @@
-export function string_from_buffer_ascii(buf) {
+import * as util from './util.js';
-    return String.fromCharCode.apply(null, new Uint8Array(buf));
-}
 
 export class StoredCell extends Array {
 }
@@ -47,8 +45,34 @@ export class StoredLevel {
 }
 
 export class StoredGame {
-    constructor(identifier) {
+    constructor(identifier, level_loader) {
         this.identifier = identifier;
-        this.levels = [];
+        this._level_loader = level_loader;
+
+        // Simple objects containing keys:
+        // title: level title
+        // index: level index, used internally only
+        // number: level number (may not match index due to C2G shenanigans)
+        // error: any error received while loading the level
+        // bytes: Uint8Array of the encoded level data
+        this.level_metadata = [];
+    }
+
+    // TODO this may or may not work sensibly when correctly following a c2g
+    load_level(index) {
+        let meta = this.level_metadata[index];
+        if (! meta)
+            throw new util.LLError(`No such level number ${index}`);
+        if (meta.error)
+            throw meta.error;
+
+        if (meta.stored_level) {
+            // The editor stores inflated levels at times, so respect that
+            return meta.stored_level;
+        }
+        else {
+            // Otherwise, attempt to load the level
+            return this._level_loader(meta.bytes, meta.number);
+        }
     }
 }

js/format-c2g.js

@@ -1,6 +1,7 @@
 import { DIRECTIONS } from './defs.js';
-import * as util from './format-util.js';
+import * as format_base from './format-base.js';
 import TILE_TYPES from './tiletypes.js';
+import * as util from './util.js';
 
 const CC2_DEMO_INPUT_MASK = {
     drop:   0x01,
@@ -13,9 +14,8 @@ const CC2_DEMO_INPUT_MASK = {
 };
 
 class CC2Demo {
-    constructor(buf) {
+    constructor(bytes) {
-        this.buf = buf;
+        this.bytes = bytes;
-        this.bytes = new Uint8Array(buf);
 
         // byte 0 is unknown, always 0?
         // Force floor seed can apparently be anything; my best guess, based on the Desert Oasis
@@ -398,8 +398,18 @@ const TILE_ENCODING = {
         has_next: true,
         extra_args: [arg_direction],
     },
-    // 0x57: Timid teeth : '#direction', '#next'
+    0x57: {
-    // 0x58: Explosion animation (unused in main levels) : '#direction', '#next'
+        name: 'teeth_timid',
+        has_next: true,
+        extra_args: [arg_direction],
+        error: "Timid chomper is not yet implemented, sorry!",
+    },
+    0x58: {
+        // TODO??? unused in main levels -- name: 'doppelganger2',
+        has_next: true,
+        extra_args: [arg_direction],
+        error: "Explosion animation is not implemented, sorry!",
+    },
     0x59: {
         name: 'hiking_boots',
         has_next: true,
@@ -410,7 +420,11 @@ const TILE_ENCODING = {
     0x5b: {
         name: 'no_player1_sign',
     },
-    // 0x5c: Inverter gate (N) : Modifier allows other gates, see below
+    0x5c: {
+        // TODO (modifier chooses logic gate) name: 'doppelganger2',
+        // TODO modifier: ...
+        error: "Logic gates are not yet implemented, sorry!",
+    },
     0x5e: {
         name: 'button_pink',
         modifier: modifier_wire,
@@ -424,7 +438,11 @@ const TILE_ENCODING = {
     0x61: {
         name: 'button_orange',
     },
-    // 0x62: Lightning bolt : '#next'
+    0x62: {
+        name: 'lightning_bolt',
+        has_next: true,
+        error: "The lightning bolt is not yet implemented, sorry!",
+    },
     0x63: {
         name: 'tank_yellow',
         has_next: true,
@@ -433,8 +451,18 @@ const TILE_ENCODING = {
     0x64: {
         name: 'button_yellow',
     },
-    // 0x65: Mirror Chip : '#direction', '#next'
+    0x65: {
-    // 0x66: Mirror Melinda : '#direction', '#next'
+        name: 'doppelganger1',
+        has_next: true,
+        extra_args: [arg_direction],
+        error: "Doppelganger Lexy is not yet implemented, sorry!",
+    },
+    0x66: {
+        name: 'doppelganger2',
+        has_next: true,
+        extra_args: [arg_direction],
+        error: "Doppelganger Cerise is not yet implemented, sorry!",
+    },
     0x68: {
         name: 'bowling_ball',
         has_next: true,
@@ -555,8 +583,14 @@ const TILE_ENCODING = {
         name: 'button_black',
         modifier: modifier_wire,
     },
-    // 0x88: ON/OFF switch (OFF) : 
+    0x88: {
-    // 0x89: ON/OFF switch (ON) : 
+        name: 'light_switch_off',
+        error: "The light switch is not yet implemented, sorry!",
+    },
+    0x89: {
+        name: 'light_switch_on',
+        error: "The light switch is not yet implemented, sorry!",
+    },
     0x8a: {
         name: 'thief_keys',
     },
@@ -576,9 +610,21 @@ const TILE_ENCODING = {
         name: 'xray_eye',
         has_next: true,
     },
-    // 0x8f: Thief bribe : '#next'
+    0x8f: {
-    // 0x90: Speed boots : '#next'
+        name: 'bribe',
-    // 0x92: Hook : '#next' 
+        has_next: true,
+        error: "The bribe is not yet implemented, sorry!",
+    },
+    0x90: {
+        name: 'speed_boots',
+        has_next: true,
+        error: "The speed boots are not yet implemented, sorry!",
+    },
+    0x91: {
+        name: 'hook',
+        has_next: true,
+        error: "The hook is not yet implemented, sorry!",
+    },
 };
 const REVERSE_TILE_ENCODING = {};
 for (let [tile_byte, spec] of Object.entries(TILE_ENCODING)) {
@@ -619,21 +665,18 @@ function read_n_bytes(view, start, n) {
     }
 }
 
-// Decompress the little ad-hoc compression scheme used for both map data and
+// Decompress the little ad-hoc compression scheme used for both map data and solution playback
-// solution playback
+function decompress(bytes) {
-function decompress(buf) {
+    let decompressed_length = new DataView(bytes.buffer, bytes.byteOffset, bytes.byteLength).getUint16(0, true);
-    let decompressed_length = new DataView(buf).getUint16(0, true);
+    let outbytes = new Uint8Array(decompressed_length);
-    let out = new ArrayBuffer(decompressed_length);
-    let outbytes = new Uint8Array(out);
-    let bytes = new Uint8Array(buf);
     let p = 2;
     let q = 0;
-    while (p < buf.byteLength) {
+    while (p < bytes.length) {
         let len = bytes[p];
         p++;
         if (len < 0x80) {
             // Data block
-            outbytes.set(new Uint8Array(buf.slice(p, p + len)), q);
+            outbytes.set(new Uint8Array(bytes.buffer, bytes.byteOffset + p, len), q);
             p += len;
             q += len;
         }
@@ -654,59 +697,85 @@ function decompress(buf) {
     }
     if (q !== decompressed_length)
         throw new Error(`Expected to decode ${decompressed_length} bytes but got ${q} instead`);
-    return out;
+    return outbytes;
 }
 
-export function parse_level(buf, number = 1) {
+// Iterates over a C2M file and yields: [section type, uint8 array view of the section]
-    let level = new util.StoredLevel(number);
+function* read_c2m_sections(buf) {
     let full_view = new DataView(buf);
     let next_section_start = 0;
-    let extra_hints = [];
-    let hint_tiles = [];
     while (next_section_start < buf.byteLength) {
         // Read section header and length
         let section_start = next_section_start;
-        let section_type = util.string_from_buffer_ascii(buf.slice(section_start, section_start + 4));
+        let section_type = util.string_from_buffer_ascii(buf, section_start, 4);
         let section_length = full_view.getUint32(section_start + 4, true);
         next_section_start = section_start + 8 + section_length;
         if (next_section_start > buf.byteLength)
-            throw new Error(`Section at byte ${section_start} of type '${section_type}' extends ${buf.length - next_section_start} bytes past the end of the file`);
+            throw new util.LLError(`Section at byte ${section_start} of type '${section_type}' extends ${buf.length - next_section_start} bytes past the end of the file`);
 
-        // This chunk marks the end of the file regardless
+        // This chunk marks the end of the file, full stop; a lot of canonical files have garbage
+        // newlines afterwards and will fail to continue to parse beyond this point
         if (section_type === 'END ')
-            break;
+            return;
 
-        if (section_type === 'CC2M' || section_type === 'LOCK' || section_type === 'VERS' ||
+        yield [section_type, new Uint8Array(buf, section_start + 8, section_length)];
-            section_type === 'TITL' || section_type === 'AUTH' ||
+    }
-            section_type === 'CLUE' || section_type === 'NOTE')
+}
+
+export function parse_level_metadata(buf) {
+    let meta = {
+        title: null,
+    };
+    for (let [type, bytes] of read_c2m_sections(buf)) {
+        if (type === 'TITL') {
+            meta.title = util.string_from_buffer_ascii(bytes, 0, bytes.length - 1).replace(/\r\n/g, "\n");
+            // TODO anything else we want for now?
+            break;
+        }
+    }
+    return meta;
+}
+
+export function parse_level(buf, number = 1) {
+    if (ArrayBuffer.isView(buf)) {
+        buf = buf.buffer;
+    }
+
+    let level = new format_base.StoredLevel(number);
+    let extra_hints = [];
+    let hint_tiles = [];
+    for (let [type, bytes] of read_c2m_sections(buf)) {
+        if (type === 'CC2M' || type === 'LOCK' || type === 'VERS' ||
+            type === 'TITL' || type === 'AUTH' ||
+            type === 'CLUE' || type === 'NOTE')
         {
             // These are all singular strings (with a terminating NUL, for some reason)
             // XXX character encoding??
-            let str = util.string_from_buffer_ascii(buf.slice(section_start + 8, next_section_start - 1)).replace(/\r\n/g, "\n");
+            let str = util.string_from_buffer_ascii(bytes, 0, bytes.length - 1).replace(/\r\n/g, "\n");
 
             // TODO store more of this, at least for idempotence, maybe
-            if (section_type === 'CC2M') {
+            if (type === 'CC2M') {
                 // File version, doesn't seem interesting
             }
-            else if (section_type === 'LOCK') {
+            else if (type === 'LOCK') {
                 // Unclear, seems to be a comment about the editor...?
             }
-            else if (section_type === 'VERS') {
+            else if (type === 'VERS') {
                 // Editor version which created this level
             }
-            else if (section_type === 'TITL') {
+            else if (type === 'TITL') {
                 // Level title
                 level.title = str;
             }
-            else if (section_type === 'AUTH') {
+            else if (type === 'AUTH') {
                 // Author's name
                 level.author = str;
             }
-            else if (section_type === 'CLUE') {
+            else if (type === 'CLUE') {
                 // Level hint
                 level.hint = str;
             }
-            else if (section_type === 'NOTE') {
+            else if (type === 'NOTE') {
                 // Author's comments...  but might also include multiple hints
                 // for levels with multiple hint tiles, delineated by [CLUE].
                 // For my purposes, extra hints are associated with the
@@ -716,16 +785,15 @@ export function parse_level(buf, number = 1) {
             continue;
         }
 
-        let section_buf = buf.slice(section_start + 8, next_section_start);
+        let view = new DataView(buf, bytes.byteOffset, bytes.byteLength);
-        let section_view = new DataView(buf, section_start + 8, section_length);
 
-        if (section_type === 'OPTN') {
+        if (type === 'OPTN') {
             // Level options, which may be truncated at any point
             // TODO implement most of these
-            level.time_limit = section_view.getUint16(0, true);
+            level.time_limit = view.getUint16(0, true);
 
             // TODO 0 - 10x10, 1 - 9x9, 2 - split, otherwise unknown which needs handling
-            let viewport = section_view.getUint8(2, true);
+            let viewport = view.getUint8(2, true);
             if (viewport === 0) {
                 level.viewport_size = 10;
             }
@@ -740,42 +808,40 @@ export function parse_level(buf, number = 1) {
                 throw new Error(`Unrecognized viewport size option ${viewport}`);
             }
 
-            if (section_view.byteLength <= 3)
+            if (view.byteLength <= 3)
                 continue;
-            //options.has_solution = section_view.getUint8(3, true);
+            //options.has_solution = view.getUint8(3, true);
 
-            if (section_view.byteLength <= 4)
+            if (view.byteLength <= 4)
                 continue;
-            //options.show_map_in_editor = section_view.getUint8(4, true);
+            //options.show_map_in_editor = view.getUint8(4, true);
 
-            if (section_view.byteLength <= 5)
+            if (view.byteLength <= 5)
                 continue;
-            //options.is_editable = section_view.getUint8(5, true);
+            //options.is_editable = view.getUint8(5, true);
 
-            if (section_view.byteLength <= 6)
+            if (view.byteLength <= 6)
                 continue;
-            //options.solution_hash = util.string_from_buffer_ascii(buf.slice(
+            //options.solution_hash = format_base.string_from_buffer_ascii(buf.slice(
                 //section_start + 6, section_start + 22));
 
-            if (section_view.byteLength <= 22)
+            if (view.byteLength <= 22)
                 continue;
-            //options.hide_logic = section_view.getUint8(22, true);
+            //options.hide_logic = view.getUint8(22, true);
 
-            if (section_view.byteLength <= 23)
+            if (view.byteLength <= 23)
                 continue;
-            level.use_cc1_boots = section_view.getUint8(23, true);
+            level.use_cc1_boots = view.getUint8(23, true);
 
-            if (section_view.byteLength <= 24)
+            if (view.byteLength <= 24)
                 continue;
-            //level.blob_behavior = section_view.getUint8(24, true);
+            //level.blob_behavior = view.getUint8(24, true);
         }
-        else if (section_type === 'MAP ' || section_type === 'PACK') {
+        else if (type === 'MAP ' || type === 'PACK') {
-            let data = section_buf;
+            if (type === 'PACK') {
-            if (section_type === 'PACK') {
+                bytes = decompress(bytes);
-                data = decompress(data);
             }
-            let bytes = new Uint8Array(data);
+            let map_view = new DataView(bytes.buffer, bytes.byteOffset, bytes.byteLength);
-            let map_view = new DataView(data);
             let width = bytes[0];
             let height = bytes[1];
             level.size_x = width;
@@ -788,17 +854,19 @@ export function parse_level(buf, number = 1) {
                 let tile_byte = bytes[p];
                 p++;
                 if (tile_byte === undefined)
-                    throw new Error(`Read past end of file in cell ${n}`);
+                    throw new util.LLError(`Read past end of file in cell ${n}`);
 
                 let spec = TILE_ENCODING[tile_byte];
                 if (! spec)
-                    throw new Error(`Unrecognized tile type 0x${tile_byte.toString(16)}`);
+                    throw new util.LLError(`Invalid tile type 0x${tile_byte.toString(16)}`);
+                if (spec.error)
+                    throw new util.LLError(spec.error);
 
                 return spec;
             }
 
             for (n = 0; n < width * height; n++) {
-                let cell = new util.StoredCell;
+                let cell = new format_base.StoredCell;
                 while (true) {
                     let spec = read_spec();
 
@@ -818,7 +886,7 @@ export function parse_level(buf, number = 1) {
                             p += 4;
                         }
                         spec = read_spec();
-                        if (! spec.modifier) {
+                        if (! spec.modifier && ! (spec.name instanceof Array)) {
                             console.warn("Got unexpected modifier for tile:", spec.name);
                         }
                     }
@@ -893,27 +961,25 @@ export function parse_level(buf, number = 1) {
                 level.linear_cells.push(cell);
             }
         }
-        else if (section_type === 'KEY ') {
+        else if (type === 'KEY ') {
         }
-        else if (section_type === 'REPL' || section_type === 'PRPL') {
+        else if (type === 'REPL' || type === 'PRPL') {
             // "Replay", i.e. demo solution
-            let data = section_buf;
+            if (type === 'PRPL') {
-            if (section_type === 'PRPL') {
+                bytes = decompress(bytes);
-                data = decompress(data);
             }
-            level.demo = new CC2Demo(data);
+            level.demo = new CC2Demo(bytes);
         }
-        else if (section_type === 'RDNY') {
+        else if (type === 'RDNY') {
         }
         // TODO LL custom chunks, should distinguish somehow
-        else if (section_type === 'LXCM') {
+        else if (type === 'LXCM') {
             // Camera regions
-            if (section_length % 4 !== 0)
+            if (bytes.length % 4 !== 0)
-                throw new Error(`Expected LXCM chunk to be a multiple of 4 bytes; got ${section_length}`);
+                throw new Error(`Expected LXCM chunk to be a multiple of 4 bytes; got ${bytes.length}`);
 
-            let bytes = new Uint8Array(section_buf);
             let p = 0;
-            while (p < section_length) {
+            while (p < bytes.length) {
                 let x = bytes[p + 0];
                 let y = bytes[p + 1];
                 let w = bytes[p + 2];
@@ -924,7 +990,7 @@ export function parse_level(buf, number = 1) {
             }
         }
         else {
-            console.warn(`Unrecognized section type '${section_type}' at offset ${section_start}`);
+            console.warn(`Unrecognized section type '${type}' at offset ${bytes.byteOffset}`);
             // TODO save it, persist when editing level
         }
     }
@@ -1171,3 +1237,479 @@ export function synthesize_level(stored_level) {
 
     return c2m.serialize();
 }
+
+
+////////////////////////////////////////////////////////////////////////////////////////////////////
+// C2G, the text format that stitches levels together into a game
+
+// NOTE: C2G is surprisingly complicated for a game layout format, and most of its features are not
+// currently supported.  Most of them have also never been used in practice, so that's fine.
+
+// TODO this is not quite right yet; the architect has more specific lexing documentation
+
+// Split a statement into a number of tokens.  This is, thankfully, relatively easy, due to the
+// minimal syntax and the lack of string escapes (so we don't have to check for " vs \" vs \\").
+// The tokens seem to be one of:
+// - a bareword (could be a variable or keyword)
+// - an operator
+// - a literal number
+// - a quoted string
+// - a label
+// - a comment
+// And that's it!  So here's a regex to find all of them, and then we just use matchAll.
+const TOKENIZE_RX = RegExp(
+    // Eat any leading horizontal whitespace
+    '[ \\t]*(?:' +
+        // 1: Catch newlines as their own thing, since they are (sigh) important, sometimes
+        '(\\n)' +
+        // 2: Comments are preceded by ; or // for some reason and run to the end of the line
+        '|(?:;|//)(.*)' +
+        // 3: Strings are double-quoted (only!) and contain no escapes
+        '|"([^"]+?)"' +
+        // 4: Labels are indicated by a #, including when used with 'goto'
+        // (the exact set of allowed characters is unclear and i'm fudging it here)
+        '|#(\\w+)' +
+        // 5: Only decimal integers are allowed
+        '|(\\d+)' +
+        // 6: Operators are part of a fixed set
+        '|(==|<=|>=|!=|&&|\\|\\||[-+*/<>=&|&^])' +
+        // 7: Barewords appear to allow literally fucking anything as long as they start with a
+        // letter -- the official playcc2 contains `really?'"` as an accidental unquoted string and
+        // it's accepted but ignored, so I can only assume it's treated as a variable
+        // TODO i really don't like this, it's beyond error-prone
+        '|([a-zA-Z]\\S*)' +
+        // 8: Anything else is an error
+        '|(\\S+)' +
+    ')', 'g');
+const DIRECTIVES = {
+    // Important stuff
+    'chdir': ['string'],
+    'do': 'statement',  // special
+    'game': ['string'],
+    'goto': ['label'],
+    'map': ['string'],
+    'music': ['string'],
+    'script': 'script',  // special
+    // Weird stuff
+    'edit': [],
+    // Seemingly unused, or at least not understood
+    'art': ['string'],
+    'chain': ['string'],
+    'dlc': ['string'],
+    'end': [],
+    'main': [],  // allegedly jumps to playcc2.c2g??
+    'wav': ['string'],
+};
+const OPERATORS = {
+    '==': {
+        argc: 2,
+    },
+    '<=': {
+    },
+    '>=': {
+    },
+    '!=': {
+    },
+    '<': {
+    },
+    '>': {
+    },
+    '=': {
+    },
+    '*': {
+    },
+    '/': {
+    },
+    '+': {
+    },
+    '-': {
+    },
+    '&&': {
+    },
+    '||': {
+    },
+    '&': {
+    },
+    '|': {
+    },
+    '%': {
+    },
+    '^': {
+    },
+};
+
+function* tokenize(statement) {
+    for (let match of statement.matchAll(TOKENIZE_RX)) {
+        if (match[1] !== undefined) {
+            // Newline(s)
+            yield {type: 'newline'};
+        }
+        else if (match[2] !== undefined) {
+            // Comment, do nothing
+        }
+        else if (match[3] !== undefined) {
+            // String
+            yield {type: 'string', value: match[3]};
+        }
+        else if (match[4] !== undefined) {
+            // Label
+            yield {type: 'label', value: match[4].toLowerCase()};
+        }
+        else if (match[5] !== undefined) {
+            // Number
+            yield {type: 'number', value: parseInt(match[5], 10)};
+        }
+        else if (match[6] !== undefined) {
+            // Operator
+            yield {type: 'op', value: match[6]};
+        }
+        else if (match[7] !== undefined) {
+            // Bareword; either a directive or a variable name
+            let word = match[7].toLowerCase();
+            if (DIRECTIVES[word] !== undefined) {
+                yield {type: 'directive', value: word};
+            }
+            else {
+                yield {type: 'variable', value: word};
+            }
+        }
+        else {
+            yield {type: 'error', value: match[8]};
+        }
+    }
+}
+
+class ParseError extends Error {
+    constructor(message, parser) {
+        super(`${message} at line ${parser.lineno}`);
+    }
+}
+
+class Parser {
+    constructor(string) {
+        this.string = string;
+        this.lexer = tokenize(string);
+        this.lineno = 1;
+        this.done = false;
+        this._peek = null;
+    }
+
+    peek() {
+        if (this._peek === null) {
+            let next = this.lexer.next();
+            if (! next.done) {
+                this._peek = next.value;
+                if (this._peek.type === 'error')
+                    throw new ParseError(`Bad syntax: ${this._peek.value}`, this);
+            }
+        }
+
+        return this._peek;
+    }
+
+    advance() {
+        if (this.done)
+            return null;
+
+        let token;
+        if (this._peek !== null) {
+            token = this._peek;
+            this._peek = null;
+        }
+        else {
+            let next = this.lexer.next();
+            if (next.done) {
+                this.done = true;
+                return null;
+            }
+
+            token = next.value;
+            if (token.type === 'error')
+                throw new ParseError(`Bad syntax: ${token.value}`, this);
+        }
+
+        if (token && token.type === 'newline') {
+            this.lineno++;
+        }
+        return token;
+    }
+
+    advance_ignore_newlines() {
+        if (this.done)
+            return null;
+
+        let token = this.advance();
+        while (token && token.type === 'newline') {
+            token = this.advance();
+        }
+
+        return token;
+    }
+
+    parse_statement() {
+        let token = this.advance_ignore_newlines();
+        if (! token)
+            return null;
+
+        // Check for a directive and handle it separately
+        if (token.type === 'directive') {
+            return this.parse_directive(token.value);
+        }
+
+        // A string (outside of a script block) doesn't seem to do anything?
+        if (token.type === 'string') {
+            return {
+                kind: 'noop',
+                tokens: [token],
+            };
+        }
+
+        // A lone label is a label declaration
+        if (token.type === 'label') {
+            return {
+                kind: 'label',
+                name: token.value,
+            };
+        }
+
+        // An operator is not a valid start; this uses RPN so values must come first
+        if (token.type === 'op')
+            throw new ParseError(`Unexpected operator: ${token.value}`, this);
+
+        // Otherwise (number, bareword presumed to be a variable), we have an RPN expression; keep
+        // consuming tokens until we finish the expression
+        let branches = [token];
+        while (true) {
+            let next = this.peek();
+            if (! next) {
+                break;
+            }
+            else if (next.type === 'number' || next.type === 'variable') {
+                let token = this.advance();
+                branches.push(token);
+            }
+            else if (next.type === 'op') {
+                let token = this.advance();
+                if (! token || token.type === 'newline')
+                    break;
+
+                // All operators are binary, so pop the last two expressions
+                if (branches.length < 2)
+                    throw new ParseError(`Not enough arguments for operator: ${token.value}`, this);
+                let a = branches.pop();
+                let b = branches.pop();
+                branches.push({
+                    op: token.value,
+                    left: a,
+                    right: b,
+                });
+
+                // TODO return now if we just did an =?
+            }
+            else {
+                break;
+            }
+        }
+
+        return {
+            kind: 'expression',
+            trees: branches,
+        };
+    }
+
+    parse_directive(name) {
+        let argspec = DIRECTIVES[name];
+        if (argspec === 'statement') {
+            // TODO implement this for real
+            // eat the rest of the line for now
+            while (true) {
+                let token = this.advance();
+                if (! token || token.type === 'newline') {
+                    break;
+                }
+            }
+        }
+        else if (argspec === 'script') {
+            // Script mode; expect a newline, then sequences of [string, values..., newline]
+            let lines = [];
+            let newline = this.advance();
+            if (newline && newline.type !== 'newline')
+                throw new ParseError(`Expected a newline after 'script' directive`, this);
+            while (true) {
+                let next = this.peek();
+                while (next && next.type === 'newline') {
+                    this.advance();
+                    next = this.peek();
+                }
+                if (! next)
+                    break;
+
+                // If this is a string, we're still in script mode; eat the whole line
+                if (next.type === 'string') {
+                    let string = this.advance();
+                    let args = [];
+                    // TODO can args be expressions??
+                    while (true) {
+                        let arg = this.advance();
+                        if (! arg || arg.type === 'newline') {
+                            break;
+                        }
+                        else if (arg.type === 'number' || arg.type === 'variable') {
+                            args.push(arg);
+                        }
+                        else {
+                            throw new ParseError(`Unexpected ${arg.type} token found in script mode: ${arg.value}`, this);
+                        }
+                    }
+                    lines.push({
+                        string: string,
+                        args: args,
+                    });
+                }
+                // If not a string, script mode is over
+                else {
+                    break;
+                }
+            }
+
+            return {
+                kind: 'script',
+                lines: lines,
+            };
+        }
+        else {
+            // Normal arguments
+            let args = [];
+            for (let argtype of argspec) {
+                let token = this.advance();
+                if (! token || token.type === 'newline') {
+                    // If we're cut off early, the whole directive is ignored
+                    return {
+                        kind: 'noop',
+                        directive: name,
+                        tokens: args,
+                    };
+                }
+                else if (token.type === argtype) {
+                    args.push(token);
+                }
+                else {
+                    throw new ParseError(`Directive ${name} expected a ${argtype} token but got ${token.type}`, this);
+                }
+            }
+            return {
+                kind: 'directive',
+                name: name,
+                args: args,
+            };
+        }
+    }
+}
+
+// C2G is a Chip's Challenge 2 format that describes the structure of a level set, which is helpful
+// since CC2 levels are all stored in separate files
+// XXX observations i have made about this hell format:
+// - newlines are optional, except after: do, map, script, goto
+// - `1 level = music "+Intro"` crashes the game
+// - `map\n"path"` is completely ignored, and in fact newlines between a directive and its arguments
+//   in general seem to separate them
+const MAX_SIMULTANEOUS_REQUESTS = 5;
+/*async*/ export function parse_game(buf, source, base_path) {
+    // TODO maybe do something with this later
+    let warn = () => {};
+
+    let resolve;
+    let promise = new Promise((res, rej) => { resolve = res });
+
+    let game = new format_base.StoredGame(undefined, parse_level);
+    let parser;
+    let active_map_fetches = new Set;
+    let pending_map_fetches = [];
+    let _fetch_map = (path, n) => {
+        let promise = source.get(base_path + '/' + path);
+        active_map_fetches.add(promise);
+
+        let meta = {
+            // TODO this will not always fly, the slot is not the same as the number
+            index: n - 1,
+            number: n,
+        };
+        game.level_metadata[meta.index] = meta;
+
+        promise.then(buf => {
+            meta.bytes = new Uint8Array(buf);
+            Object.assign(meta, parse_level_metadata(buf));
+        })
+        .then(null, err => {
+            // TODO should have: what level, what file, position, etc attached to errors
+            console.error(err);
+            meta.error = err;
+        })
+        .then(() => {
+            // Always remove our promise and start a new map load if any are waiting
+            active_map_fetches.delete(promise);
+            if (active_map_fetches.size < MAX_SIMULTANEOUS_REQUESTS && pending_map_fetches.length > 0) {
+                _fetch_map(...pending_map_fetches.shift());
+            }
+            else if (active_map_fetches.size === 0 && pending_map_fetches.length === 0 && parser.done) {
+                // FIXME this is a bit of a mess
+                resolve(game);
+            }
+        });
+    };
+    let fetch_map = (path, n) => {
+        if (active_map_fetches.size >= MAX_SIMULTANEOUS_REQUESTS) {
+            pending_map_fetches.push([path, n]);
+            return;
+        }
+
+        _fetch_map(path, n);
+    };
+    
+    // FIXME and right off the bat we have an Issue: this is a text format so i want a string, not
+    // an arraybuffer!
+    let contents = util.string_from_buffer_ascii(buf);
+    parser = new Parser(contents);
+    let statements = [];
+    let level_number = 1;
+    while (! parser.done) {
+        let stmt = parser.parse_statement();
+        if (stmt === null)
+            break;
+
+        // TODO search 'do' as well
+        if (stmt.kind === 'directive' && stmt.name === 'map') {
+            let path = stmt.args[0].value;
+            path = path.replace(/\\/, '/');
+            fetch_map(path, level_number);
+            level_number++;
+        }
+        statements.push(stmt);
+    }
+
+    // FIXME grody
+    if (active_map_fetches.size === 0 && pending_map_fetches.length === 0) {
+        resolve(game);
+    }
+
+    console.log(game);
+    return promise;
+}
+
+// Individual levels don't make sense on their own, but we can wrap them in a dummy one-level game
+export function wrap_individual_level(buf) {
+    let game = new format_base.StoredGame(undefined, parse_level);
+    let meta = {
+        index: 0,
+        number: 1,
+        bytes: new Uint8Array(buf),
+    };
+    try {
+        Object.assign(meta, parse_level_metadata(buf));
+    }
+    catch (e) {
+        meta.error = e;
+    }
+    game.level_metadata.push(meta);
+    return game;
+}

js/format-dat.js

@@ -1,5 +1,6 @@
-import * as util from './format-util.js';
+import * as format_base from './format-base.js';
 import TILE_TYPES from './tiletypes.js';
+import * as util from './util.js';
 
 const TILE_ENCODING = {
     0x00: 'floor',
@@ -118,21 +119,71 @@ const TILE_ENCODING = {
     0x6e: ['player', 'south'],
     0x6f: ['player', 'east'],
 };
-    
+
-function parse_level(buf, number) {
+function decode_password(bytes, start, len) {
-    let level = new util.StoredLevel(number);
+    let password = [];
+    for (let i = 0; i < len; i++) {
+        password.push(bytes[start + i] ^ 0x99);
+    }
+    return String.fromCharCode.apply(null, password);
+}
+
+export function parse_level_metadata(bytes) {
+    let meta = {};
+
+    let view = new DataView(bytes.buffer, bytes.byteOffset, bytes.byteLength);
+
+    // Level number; rest of level header is unused
+    meta.number = view.getUint16(0, true);
+
+    // Map layout
+    // Same structure twice, for the two layers
+    let p = 8;
+    for (let l = 0; l < 2; l++) {
+        let layer_length = view.getUint16(p, true);
+        p += 2 + layer_length;
+    }
+
+    // Optional metadata fields
+    let meta_length = view.getUint16(p, true);
+    p += 2;
+    let end = p + meta_length;
+    while (p < end) {
+        // Common header
+        let field_type = view.getUint8(p, true);
+        let field_length = view.getUint8(p + 1, true);
+        p += 2;
+        if (field_type === 0x03) {
+            // Title, including trailing NUL
+            meta.title = util.string_from_buffer_ascii(bytes, p, field_length - 1);
+        }
+        else if (field_type === 0x06) {
+            // Password, with trailing NUL, and XORed with 0x99 (???)
+            meta.password = decode_password(bytes, p, field_length - 1);
+        }
+        else if (field_type === 0x07) {
+            // Hint, including trailing NUL, of course
+            meta.hint = util.string_from_buffer_ascii(bytes, p, field_length - 1);
+        }
+        p += field_length;
+    }
+
+    return meta;
+}
+
+function parse_level(bytes, number) {
+    let level = new format_base.StoredLevel(number);
     level.has_custom_connections = true;
     level.use_ccl_compat = true;
     // Map size is always fixed as 32x32 in CC1
     level.size_x = 32;
     level.size_y = 32;
     for (let i = 0; i < 1024; i++) {
-        level.linear_cells.push(new util.StoredCell);
+        level.linear_cells.push(new format_base.StoredCell);
     }
     level.use_cc1_boots = true;
 
-    let view = new DataView(buf);
+    let view = new DataView(bytes.buffer, bytes.byteOffset, bytes.byteLength);
-    let bytes = new Uint8Array(buf);
 
     // Header
     let level_number = view.getUint16(0, true);
@@ -163,7 +214,7 @@ function parse_level(buf, number) {
             // TODO could be more forgiving for goofy levels doing goofy things
             if (! spec) {
                 let [x, y] = level.scalar_to_coords(c);
-                throw new Error(`Invalid tile byte 0x${tile_byte.toString(16)} at (${x}, ${y}) in level ${number}`);
+                throw new Error(`Invalid tile byte 0x${tile_byte.toString(16)} at (${x}, ${y})`);
             }
 
             let name, direction;
@@ -227,11 +278,11 @@ function parse_level(buf, number) {
         }
         else if (field_type === 0x03) {
             // Title, including trailing NUL
-            level.title = util.string_from_buffer_ascii(buf.slice(p, p + field_length - 1));
+            level.title = util.string_from_buffer_ascii(bytes, p, field_length - 1);
         }
         else if (field_type === 0x04) {
             // Trap linkages (MSCC only, not in Lynx or CC2)
-            let field_view = new DataView(buf.slice(p, p + field_length));
+            let field_view = new DataView(bytes.buffer, bytes.byteOffset + p, field_length);
             let q = 0;
             while (q < field_length) {
                 let button_x = field_view.getUint16(q + 0, true);
@@ -245,7 +296,7 @@ function parse_level(buf, number) {
         }
         else if (field_type === 0x05) {
             // Cloner linkages (MSCC only, not in Lynx or CC2)
-            let field_view = new DataView(buf.slice(p, p + field_length));
+            let field_view = new DataView(bytes.buffer, bytes.byteOffset + p, field_length);
             let q = 0;
             while (q < field_length) {
                 let button_x = field_view.getUint16(q + 0, true);
@@ -257,16 +308,12 @@ function parse_level(buf, number) {
             }
         }
         else if (field_type === 0x06) {
-            // Password, with trailing NUL, and otherwise XORed with 0x99 (?!)
+            // Password, with trailing NUL, and otherwise XORed with 0x99 (???)
-            let password = [];
+            level.password = decode_password(bytes, p, field_length - 1);
-            for (let i = 0; i < field_length - 1; i++) {
-                password.push(view.getUint8(p + i, true) ^ 0x99);
-            }
-            level.password = String.fromCharCode.apply(null, password);
         }
         else if (field_type === 0x07) {
             // Hint, including trailing NUL, of course
-            level.hint = util.string_from_buffer_ascii(buf.slice(p, p + field_length - 1));
+            level.hint = util.string_from_buffer_ascii(bytes, p, field_length - 1);
         }
         else if (field_type === 0x08) {
             // Password, but not encoded
@@ -283,7 +330,7 @@ function parse_level(buf, number) {
 }
 
 export function parse_game(buf) {
-    let game = new util.StoredGame;
+    let game = new format_base.StoredGame(null, parse_level);
 
     let full_view = new DataView(buf);
     let magic = full_view.getUint32(0, true);
@@ -305,11 +352,19 @@ export function parse_game(buf) {
     let p = 6;
     for (let l = 1; l <= level_count; l++) {
         let length = full_view.getUint16(p, true);
-        let level_buf = buf.slice(p + 2, p + 2 + length);
+        let bytes = new Uint8Array(buf, p + 2, length);
         p += 2 + length;
 
-        let level = parse_level(level_buf, l);
+        let meta;
-        game.levels.push(level);
+        try {
+            meta = parse_level_metadata(bytes);
+        }
+        catch (e) {
+            meta = {error: e};
+        }
+        meta.index = l - 1;
+        meta.bytes = bytes;
+        game.level_metadata.push(meta);
     }
 
     return game;

js/game.js

@@ -253,22 +253,18 @@ export class Level {
 
                     if (tile.type.is_player) {
                         // TODO handle multiple players, also chip and melinda both
-                        // TODO complain if no chip
+                        // TODO complain if no player
                         this.player = tile;
-                        // Always put the player at the start of the actor list
-                        // (accomplished traditionally with a swap)
-                        this.actors.push(this.actors[0]);
-                        this.actors[0] = tile;
                     }
-                    else if (tile.type.is_actor) {
+                    if (tile.type.is_actor) {
                         if (has_cloner) {
                             // TODO is there any reason not to add clone templates to the actor
                             // list?
                             tile.stuck = true;
                         }
-                        else {
+                    }
-                            this.actors.push(tile);
+                    if (! tile.stuck) {
-                        }
+                        this.actors.push(tile);
                     }
                     cell._add(tile);
 
@@ -391,7 +387,13 @@ export class Level {
         // immediately), we still want every time's animation to finish, or it'll look like some
         // objects move backwards when the death screen appears!
         let cell_steppers = [];
-        for (let actor of this.actors) {
+        // Note that we iterate in reverse order, DESPITE keeping dead actors around with null
+        // cells, to match the Lynx and CC2 behavior.  This is actually important in some cases;
+        // check out the start of CCLP3 #54, where the gliders will eat the blue key immediately if
+        // they act in forward order!  (More subtly, even the earlier passes do things like advance
+        // the RNG, so for replay compatibility they need to be in reverse order too.)
+        for (let i = this.actors.length - 1; i >= 0; i--) {
+            let actor = this.actors[i];
             // Actors with no cell were destroyed
             if (! actor.cell)
                 continue;
@@ -442,8 +444,10 @@ export class Level {
 
         // Second pass: actors decide their upcoming movement simultaneously
         // (we'll do the player's decision in part 2!)
-        for (let actor of this.actors) {
+        for (let i = this.actors.length - 1; i >= 0; i--) {
+            let actor = this.actors[i];
             if (actor != this.player)
+                continue;
             {
                 this.actor_decision(actor, p1_primary_direction);
             }
@@ -456,7 +460,8 @@ export class Level {
         this.actor_decision(this.player, p1_primary_direction);
         
         // Third pass: everyone actually moves
-        for (let actor of this.actors) {
+        for (let i = this.actors.length - 1; i >= 0; i--) {
+            let actor = this.actors[i];
             if (! actor.cell)
                 continue;
 

js/main-editor.js

@@ -1,5 +1,5 @@
 import { DIRECTIONS, TICS_PER_SECOND } from './defs.js';
-import * as c2m from './format-c2m.js';
+import * as c2g from './format-c2g.js';
 import { PrimaryView, DialogOverlay } from './main-base.js';
 import CanvasRenderer from './renderer-canvas.js';
 import TILE_TYPES from './tiletypes.js';
@@ -617,7 +617,7 @@ export class Editor extends PrimaryView {
 
         // Toolbar buttons
         this.root.querySelector('#editor-share-url').addEventListener('click', ev => {
-            let buf = c2m.synthesize_level(this.stored_level);
+            let buf = c2g.synthesize_level(this.stored_level);
             // FIXME Not ideal, but btoa() wants a string rather than any of the myriad binary types
             let stringy_buf = Array.from(new Uint8Array(buf)).map(n => String.fromCharCode(n)).join('');
             // Make URL-safe and strip trailing padding

js/main.js

@@ -1,9 +1,9 @@
 // TODO bugs and quirks i'm aware of:
 // - steam: if a player character starts on a force floor they won't be able to make any voluntary movements until they are no longer on a force floor
 import { DIRECTIONS, TICS_PER_SECOND } from './defs.js';
-import * as c2m from './format-c2m.js';
+import * as c2g from './format-c2g.js';
 import * as dat from './format-dat.js';
-import * as format_util from './format-util.js';
+import * as format_base from './format-base.js';
 import { Level } from './game.js';
 import { PrimaryView, Overlay, DialogOverlay, ConfirmOverlay } from './main-base.js';
 import { Editor } from './main-editor.js';
@@ -11,7 +11,8 @@ import CanvasRenderer from './renderer-canvas.js';
 import SOUNDTRACK from './soundtrack.js';
 import { Tileset, CC2_TILESET_LAYOUT, LL_TILESET_LAYOUT, TILE_WORLD_TILESET_LAYOUT } from './tileset.js';
 import TILE_TYPES from './tiletypes.js';
-import { random_choice, mk, mk_svg, promise_event, fetch } from './util.js';
+import { random_choice, mk, mk_svg, promise_event } from './util.js';
+import * as util from './util.js';
 
 const PAGE_TITLE = "Lexy's Labyrinth";
 
@@ -167,7 +168,7 @@ class SFXPlayer {
     }
 
     async init_sound(name, path) {
-        let buf = await fetch(path);
+        let buf = await util.fetch(path);
         let audiobuf = await this.ctx.decodeAudioData(buf);
         this.sounds[name] = {
             buf: buf,
@@ -1312,9 +1313,15 @@ class Splash extends PrimaryView {
             let score;
             let packinfo = conductor.stash.packs[packdef.ident];
             if (packinfo && packinfo.total_score !== undefined) {
-                // TODO tack on a star if the game is "beaten"?  what's that mean?  every level
+                if (packinfo.total_score === null) {
-                // beaten i guess?
+                    // Whoops, some NaNs got in here  :(
-                score = packinfo.total_score.toLocaleString();
+                    score = "computing...";
+                }
+                else {
+                    // TODO tack on a star if the game is "beaten"?  what's that mean?  every level
+                    // beaten i guess?
+                    score = packinfo.total_score.toLocaleString();
+                }
             }
             else {
                 score = "unplayed";
@@ -1326,87 +1333,109 @@ class Splash extends PrimaryView {
                 mk('span.-score', score),
             );
             button.addEventListener('click', ev => {
-                this.fetch_pack(packdef.path, packdef.title);
+                this.conductor.fetch_pack(packdef.path, packdef.title);
             });
             pack_list.append(button);
         }
 
-        // Bind to file upload control
+        // File loading: allow providing either a single file, multiple files, OR an entire
-        let upload_el = this.root.querySelector('#splash-upload');
+        // directory (via the hokey WebKit Entry interface)
-        // Clear it out in case of refresh
+        let upload_file_el = this.root.querySelector('#splash-upload-file');
-        upload_el.value = '';
+        let upload_dir_el = this.root.querySelector('#splash-upload-dir');
-        this.root.querySelector('#splash-upload-button').addEventListener('click', ev => {
+        // Clear out the file controls in case of refresh
-            upload_el.click();
+        upload_file_el.value = '';
+        upload_dir_el.value = '';
+        this.root.querySelector('#splash-upload-file-button').addEventListener('click', ev => {
+            upload_file_el.click();
         });
-        upload_el.addEventListener('change', async ev => {
+        this.root.querySelector('#splash-upload-dir-button').addEventListener('click', ev => {
+            upload_dir_el.click();
+        });
+        upload_file_el.addEventListener('change', async ev => {
+            if (upload_file_el.files.length === 0)
+                return;
+
+            // TODO throw up a 'loading' overlay
+            // FIXME handle multiple files!  but if there's only one, explicitly load /that/ one
             let file = ev.target.files[0];
             let buf = await file.arrayBuffer();
-            this.load_file(buf, this.extract_identifier_from_path(file.name));
+            await this.conductor.parse_and_load_game(buf, new util.FileFileSource(ev.target.files), file.name);
-            // TODO get title out of C2G when it's supported
+        });
-            this.conductor.level_pack_name_el.textContent = file.name;
+        upload_dir_el.addEventListener('change', async ev => {
+            // TODO throw up a 'loading' overlay
+            // The directory selector populates 'files' with every single file, recursively, which
+            // is kind of wild but also /much/ easier to deal with
+            let files = upload_dir_el.files;
+            if (files.length > 4096)
+                throw new util.LLError("Got way too many files; did you upload the right directory?");
+
+            await this.search_multi_source(new util.FileFileSource(files));
+        });
+        // Allow loading a local directory onto us, via the WebKit
+        // file entry interface
+        // TODO? this always takes a moment to register, not sure why...
+        // FIXME as written this won't correctly handle CCLs
+        util.handle_drop(this.root, {
+            require_file: true,
+            dropzone_class: '--drag-hover',
+            on_drop: async ev => {
+                // TODO for now, always use the entry interface, but if these are all files then
+                // they can just be loaded normally
+                let entries = [];
+                for (let item of ev.dataTransfer.items) {
+                    entries.push(item.webkitGetAsEntry());
+                }
+                await this.search_multi_source(new util.EntryFileSource(entries));
+            },
         });
 
         // Bind to "create level" button
         this.root.querySelector('#splash-create-level').addEventListener('click', ev => {
-            let stored_level = new format_util.StoredLevel;
+            let stored_level = new format_base.StoredLevel(1);
             stored_level.size_x = 32;
             stored_level.size_y = 32;
             for (let i = 0; i < 1024; i++) {
-                let cell = new format_util.StoredCell;
+                let cell = new format_base.StoredCell;
                 cell.push({type: TILE_TYPES['floor']});
                 stored_level.linear_cells.push(cell);
             }
             stored_level.linear_cells[0].push({type: TILE_TYPES['player']});
 
             // FIXME definitely gonna need a name here chief
-            let stored_game = new format_util.StoredGame(null);
+            let stored_game = new format_base.StoredGame(null);
-            stored_game.levels.push(stored_level);
+            stored_game.level_metadata.push({
+                stored_level: stored_level,
+            });
             this.conductor.load_game(stored_game);
 
             this.conductor.switch_to_editor();
         });
     }
 
-    extract_identifier_from_path(path) {
+    // Look for something we can load, and load it
-        let ident = path.match(/^(?:.*\/)?[.]*([^.]+)(?:[.]|$)/)[1];
+    async search_multi_source(source) {
-        if (ident) {
+        // TODO not entiiirely kosher, but not sure if we should have an api for this or what
-            return ident.toLowerCase();
+        if (source._loaded_promise) {
+            await source._loaded_promise;
         }
-        else {
-            return null;
-        }
-    }
 
-    // TODO wait why aren't these just on conductor
+        let paths = Object.keys(source.files);
-    async fetch_pack(path, title) {
+        // TODO should handle having multiple candidates, but this is good enough for now
-        // TODO indicate we're downloading something
+        paths.sort((a, b) => a.length - b.length);
-        // TODO handle errors
+        for (let path of paths) {
-        // TODO cancel a download if we start another one?
+            let m = path.match(/[.]([^./]+)$/);
-        let buf = await fetch(path);
+            if (! m)
-        this.load_file(buf, this.extract_identifier_from_path(path));
+                continue;
-        // TODO get title out of C2G when it's supported
-        this.conductor.level_pack_name_el.textContent = title || path;
-    }
 
-    load_file(buf, identifier = null) {
+            let ext = m[1];
-        // TODO also support tile world's DAC when reading from local??
+            // TODO this can't load an individual c2m, hmmm
-        // TODO ah, there's more metadata in CCX, crapola
+            if (ext === 'c2g' || ext === 'dat' || ext === 'ccl') {
-        let magic = String.fromCharCode.apply(null, new Uint8Array(buf.slice(0, 4)));
+                let buf = await source.get(path);
-        let stored_game;
+                await this.conductor.parse_and_load_game(buf, source, path);
-        if (magic === 'CC2M' || magic === 'CCS ') {
+                break;
-            stored_game = new format_util.StoredGame;
+            }
-            stored_game.levels.push(c2m.parse_level(buf));
-            // Don't make a savefile for individual levels
-            identifier = null;
         }
-        else if (magic === '\xac\xaa\x02\x00' || magic == '\xac\xaa\x02\x01') {
+        // TODO else...?  complain we couldn't find anything?  list what we did find??  idk
-            stored_game = dat.parse_game(buf);
-        }
-        else {
-            throw new Error("Unrecognized file format");
-        }
-        this.conductor.load_game(stored_game, identifier);
-        this.conductor.switch_to_player();
     }
 }
 
@@ -1414,6 +1443,30 @@ class Splash extends PrimaryView {
 // -------------------------------------------------------------------------------------------------
 // Central controller, thingy
 
+// Report an error when a level fails to load
+class LevelErrorOverlay extends DialogOverlay {
+    constructor(conductor, error) {
+        super(conductor);
+        this.set_title("bummer");
+        this.main.append(
+            mk('p', "Whoopsadoodle!  I seem to be having some trouble loading this level.  I got this error, which may or may not be useful:"),
+            mk('pre.error', error.toString()),
+            mk('p',
+                "It's probably entirely my fault, and I'm very sorry.  ",
+                "Unless you're doing something weird and it's actually your fault, I guess.  ",
+                "This is just a prerecorded message, so it's hard for me to tell!  ",
+                "But if it's my fault and you're feeling up to it, you can let me know by ",
+                mk('a', {href: 'https://github.com/eevee/lexys-labyrinth/issues'}, "filing an issue on GitHub"),
+                " or finding me on Discord or Twitter or whatever.",
+            ),
+            mk('p', "In the more immediate future, you can see if any other levels work by jumping around manually with the 'level select' button.  Unless this was the first level of a set, in which case you're completely out of luck."),
+        );
+        this.add_button("welp, you get what you pay for", ev => {
+            this.close();
+        });
+    }
+}
+
 // About dialog
 const ABOUT_HTML = `
 <p>Welcome to Lexy's Labyrinth, an exciting old-school tile-based puzzle adventure that is compatible with — but legally distinct from! — <a href="https://store.steampowered.com/app/346850/Chips_Challenge_1/">Chip's Challenge</a> and its long-awaited sequel <a href="https://store.steampowered.com/app/348300/Chips_Challenge_2/">Chip's Challenge 2</a>.</p>
@@ -1613,7 +1666,7 @@ class LevelBrowserOverlay extends DialogOverlay {
         this.main.append(table);
         let savefile = conductor.current_pack_savefile;
         // TODO if i stop eagerloading everything in a .DAT then this will not make sense any more
-        for (let [i, stored_level] of conductor.stored_game.levels.entries()) {
+        for (let [i, meta] of conductor.stored_game.level_metadata.entries()) {
             let scorecard = savefile.scorecards[i];
             let score = "—", time = "—", abstime = "—";
             if (scorecard) {
@@ -1637,10 +1690,18 @@ class LevelBrowserOverlay extends DialogOverlay {
                 abstime = `${absmin}:${abssec < 10 ? '0' : ''}${abssec.toFixed(2)}`;
             }
 
-            tbody.append(mk(i >= savefile.highest_level ? 'tr.--unvisited' : 'tr',
+            let title = meta.title;
+            if (meta.error) {
+                title = '[failed to load]';
+            }
+            else if (! title) {
+                title = '(untitled)';
+            }
+
+            let tr = mk('tr',
                 {'data-index': i},
-                mk('td.-number', i + 1),
+                mk('td.-number', meta.number),
-                mk('td.-title', stored_level.title),
+                mk('td.-title', title),
                 mk('td.-time', time),
                 mk('td.-time', abstime),
                 mk('td.-score', score),
@@ -1649,7 +1710,17 @@ class LevelBrowserOverlay extends DialogOverlay {
                 // your wallclock time also?
                 // TODO other stats??  num chips, time limit?  don't know that without loading all
                 // the levels upfront though, which i currently do but want to stop doing
-            ));
+            );
+
+            // TODO sigh, does not actually indicate visited in C2G world
+            if (i >= savefile.highest_level) {
+                tr.classList.add('--unvisited');
+            }
+            if (meta.error) {
+                tr.classList.add('--error');
+            }
+
+            tbody.append(tr);
         }
 
         tbody.addEventListener('click', ev => {
@@ -1658,8 +1729,9 @@ class LevelBrowserOverlay extends DialogOverlay {
                 return;
 
             let index = parseInt(tr.getAttribute('data-index'), 10);
-            this.conductor.change_level(index);
+            if (this.conductor.change_level(index)) {
-            this.close();
+                this.close();
+            }
         });
 
         this.add_button("nevermind", ev => {
@@ -1718,7 +1790,7 @@ class Conductor {
         });
         this.nav_next_button.addEventListener('click', ev => {
             // TODO confirm
-            if (this.stored_game && this.level_index < this.stored_game.levels.length - 1) {
+            if (this.stored_game && this.level_index < this.stored_game.level_metadata.length - 1) {
                 this.change_level(this.level_index + 1);
             }
             ev.target.blur();
@@ -1786,6 +1858,13 @@ class Conductor {
         if (identifier !== null) {
             // TODO again, enforce something about the shape here
             this.current_pack_savefile = JSON.parse(window.localStorage.getItem(STORAGE_PACK_PREFIX + identifier));
+            if (this.current_pack_savefile.total_score === null) {
+                // Fix some NaNs that slipped in
+                this.current_pack_savefile.total_score = this.current_pack_savefile.scorecards
+                    .map(scorecard => scorecard ? scorecard.score : 0)
+                    .reduce((a, b) => a + b, 0);
+                this.save_savefile();
+            }
         }
         if (! this.current_pack_savefile) {
             this.current_pack_savefile = {
@@ -1800,12 +1879,20 @@ class Conductor {
         this.player.load_game(stored_game);
         this.editor.load_game(stored_game);
 
-        this.change_level(0);
+        return this.change_level(0);
     }
 
     change_level(level_index) {
+        // FIXME handle errors here
+        try {
+            this.stored_level = this.stored_game.load_level(level_index);
+        }
+        catch (e) {
+            new LevelErrorOverlay(this, e).open();
+            return false;
+        }
+
         this.level_index = level_index;
-        this.stored_level = this.stored_game.levels[level_index];
 
         // FIXME do better
         this.level_name_el.textContent = `Level ${level_index + 1} — ${this.stored_level.title}`;
@@ -1815,12 +1902,13 @@ class Conductor {
 
         this.player.load_level(this.stored_level);
         this.editor.load_level(this.stored_level);
+        return true;
     }
 
     update_nav_buttons() {
         this.nav_choose_level_button.disabled = !this.stored_game;
         this.nav_prev_button.disabled = !this.stored_game || this.level_index <= 0;
-        this.nav_next_button.disabled = !this.stored_game || this.level_index >= this.stored_game.levels.length;
+        this.nav_next_button.disabled = !this.stored_game || this.level_index >= this.stored_game.level_metadata.length;
     }
 
     save_stash() {
@@ -1845,6 +1933,68 @@ class Conductor {
             this.save_stash();
         }
     }
+
+    // ------------------------------------------------------------------------------------------------
+    // File loading
+
+    extract_identifier_from_path(path) {
+        let ident = path.match(/^(?:.*\/)?[.]*([^.]+)(?:[.]|$)/)[1];
+        if (ident) {
+            return ident.toLowerCase();
+        }
+        else {
+            return null;
+        }
+    }
+
+    async fetch_pack(path, title) {
+        // TODO indicate we're downloading something
+        // TODO handle errors
+        // TODO cancel a download if we start another one?
+        let buf = await util.fetch(path);
+        await this.parse_and_load_game(buf, new util.HTTPFileSource(new URL(location)), path);
+    }
+
+    async parse_and_load_game(buf, source, path, identifier, title) {
+        if (identifier === undefined) {
+            identifier = this.extract_identifier_from_path(path);
+        }
+
+        // TODO get title out of C2G when it's supported
+        this.level_pack_name_el.textContent = title ?? identifier ?? '(untitled)';
+
+        // TODO also support tile world's DAC when reading from local??
+        // TODO ah, there's more metadata in CCX, crapola
+        let magic = String.fromCharCode.apply(null, new Uint8Array(buf.slice(0, 4)));
+        let stored_game;
+        if (magic === 'CC2M' || magic === 'CCS ') {
+            // This is an individual level, so concoct a fake game for it, and don't save anything
+            stored_game = c2g.wrap_individual_level(buf);
+            identifier = null;
+        }
+        else if (magic === '\xac\xaa\x02\x00' || magic == '\xac\xaa\x02\x01') {
+            stored_game = dat.parse_game(buf);
+        }
+        else if (magic.toLowerCase() === 'game') {
+            // TODO this isn't really a magic number and isn't required to be first, so, maybe
+            // this one should just go by filename
+            console.log(path);
+            let dir;
+            if (! path.match(/[/]/)) {
+                dir = '';
+            }
+            else {
+                dir = path.replace(/[/][^/]+$/, '');
+            }
+            stored_game = await c2g.parse_game(buf, source, dir);
+        }
+        else {
+            throw new Error("Unrecognized file format");
+        }
+        if (this.load_game(stored_game, identifier)) {
+            this.switch_to_player();
+        }
+    }
 }
 
 
@@ -1891,14 +2041,14 @@ async function main() {
     let path = query.get('setpath');
     let b64level = query.get('level');
     if (path && path.match(/^levels[/]/)) {
-        conductor.splash.fetch_pack(path);
+        conductor.fetch_pack(path);
     }
     else if (b64level) {
         // TODO all the more important to show errors!!
         // FIXME Not ideal, but atob() returns a string rather than any of the myriad binary types
         let stringy_buf = atob(b64level.replace(/-/g, '+').replace(/_/g, '/'));
         let buf = Uint8Array.from(stringy_buf, c => c.charCodeAt(0)).buffer;
-        conductor.splash.load_file(buf);
+        await conductor.parse_and_load_game(buf, null, 'shared.c2m', null, "Shared level");
     }
 }
 

js/tiletypes.js

@@ -882,7 +882,8 @@ const TILE_TYPES = {
             level.sfx.play_once('button-press', me.cell);
 
             // Move all yellow tanks one tile in the direction of the pressing actor
-            for (let actor of level.actors) {
+            for (let i = level.actors.length - 1; i >= 0; i--) {
+                let actor = level.actors[i];
                 // TODO generify somehow??
                 if (actor.type.name === 'tank_yellow') {
                     level.attempt_step(actor, other.direction);

js/util.js

@@ -1,7 +1,13 @@
+// Base class for custom errors
+export class LLError extends Error {}
+
+// Random choice
 export function random_choice(list) {
     return list[Math.floor(Math.random() * list.length)];
 }
 
+
+// DOM stuff
 function _mk(el, children) {
     if (children.length > 0) {
         if (!(children[0] instanceof Node) && children[0] !== undefined && typeof(children[0]) !== "string" && typeof(children[0]) !== "number") {
@@ -29,6 +35,70 @@ export function mk_svg(tag_selector, ...children) {
     return _mk(el, children);
 }
 
+export function handle_drop(element, options) {
+    let dropzone_class = options.dropzone_class ?? null;
+    let on_drop = options.on_drop;
+
+    let require_file = options.require_file ?? false;
+    let is_valid = ev => {
+        // TODO this requires files, should make some args for this
+        if (options.require_file) {
+            let dt = ev.dataTransfer;
+            if (! dt || dt.items.length === 0)
+                return false;
+
+            // Only test the first item I guess?  If it's a file then they should all be files
+            if (dt.items[0].kind !== 'file')
+                return false;
+        }
+
+        return true;
+    };
+
+    let end_drop = () => {
+        if (dropzone_class !== null) {
+            element.classList.remove(dropzone_class);
+        }
+    };
+
+    // TODO should have a filter function for when a drag is valid but i forget which of these
+    // should have that
+    element.addEventListener('dragenter', ev => {
+        if (! is_valid(ev))
+            return;
+
+        ev.stopPropagation();
+        ev.preventDefault();
+
+        if (dropzone_class !== null) {
+            element.classList.add(dropzone_class);
+        }
+    });
+    element.addEventListener('dragover', ev => {
+        if (! is_valid(ev))
+            return;
+
+        ev.stopPropagation();
+        ev.preventDefault();
+    });
+    element.addEventListener('dragleave', ev => {
+        if (ev.relatedTarget && element.contains(ev.relatedTarget))
+            return;
+
+        end_drop();
+    });
+    element.addEventListener('drop', ev => {
+        if (! is_valid(ev))
+            return;
+
+        ev.stopPropagation();
+        ev.preventDefault();
+
+        end_drop();
+        on_drop(ev);
+    });
+}
+
 export function promise_event(element, success_event, failure_event) {
     let resolve, reject;
     let promise = new Promise((res, rej) => {
@@ -36,21 +106,21 @@ export function promise_event(element, success_event, failure_event) {
         reject = rej;
     });
 
-    let success_handler = e => {
+    let success_handler = ev => {
         element.removeEventListener(success_event, success_handler);
         if (failure_event) {
             element.removeEventListener(failure_event, failure_handler);
         }
 
-        resolve(e);
+        resolve(ev);
     };
-    let failure_handler = e => {
+    let failure_handler = ev => {
         element.removeEventListener(success_event, success_handler);
         if (failure_event) {
             element.removeEventListener(failure_event, failure_handler);
         }
 
-        reject(e);
+        reject(ev);
     };
 
     element.addEventListener(success_event, success_handler);
@@ -61,6 +131,7 @@ export function promise_event(element, success_event, failure_event) {
     return promise;
 }
 
+
 export async function fetch(url) {
     let xhr = new XMLHttpRequest;
     let promise = promise_event(xhr, 'load', 'error');
@@ -68,9 +139,19 @@ export async function fetch(url) {
     xhr.responseType = 'arraybuffer';
     xhr.send();
     await promise;
+    if (xhr.status !== 200)
+        throw new Error(`Failed to load ${url} -- ${xhr.status} ${xhr.statusText}`);
     return xhr.response;
 }
 
+export function string_from_buffer_ascii(buf, start = 0, len) {
+    if (ArrayBuffer.isView(buf)) {
+        start += buf.byteOffset;
+        buf = buf.buffer;
+    }
+    return String.fromCharCode.apply(null, new Uint8Array(buf, start, len));
+}
+
 // Cast a line through a grid and yield every cell it touches
 export function* walk_grid(x0, y0, x1, y1) {
     // TODO if the ray starts outside the grid (extremely unlikely), we should
@@ -171,3 +252,101 @@ export function* walk_grid(x0, y0, x1, y1) {
         }
     }
 }
+
+// Root class to indirect over where we might get files from
+// - a pool of uploaded in-memory files
+// - a single uploaded zip file
+// - a local directory provided via the webkit Entry api
+// - HTTP (but only for files we choose ourselves, not arbitrary ones, due to CORS)
+// Note that where possible, these classes lowercase all filenames, in keeping with C2G's implicit
+// requirement that filenames are case-insensitive  :/
+class FileSource {
+    constructor() {}
+
+    // Get a file's contents as an ArrayBuffer
+    async get(path) {}
+}
+// Files we have had uploaded one at a time (note that each upload becomes its own source)
+export class FileFileSource extends FileSource {
+    constructor(files) {
+        super();
+        this.files = {};
+        for (let file of files) {
+            this.files[(file.webkitRelativePath ?? file.name).toLowerCase()] = file;
+        }
+    }
+
+    get(path) {
+        let file = this.files[path.toLowerCase()];
+        if (file) {
+            return file.arrayBuffer();
+        }
+        else {
+            return Promise.reject(new Error(`No such file was provided: ${path}`));
+        }
+    }
+}
+// Regular HTTP fetch
+export class HTTPFileSource extends FileSource {
+    // Should be given a URL object as a root
+    constructor(root) {
+        super();
+        this.root = root;
+    }
+
+    get(path) {
+        let url = new URL(path, this.root);
+        return fetch(url);
+    }
+}
+// WebKit Entry interface
+// XXX this does not appear to work if you drag in a link to a directory but that is probably beyond
+// my powers to fix
+export class EntryFileSource extends FileSource {
+    constructor(entries) {
+        super();
+        this.files = {};
+        let file_count = 0;
+
+        let read_directory = async (directory_entry, dir_prefix) => {
+            let reader = directory_entry.createReader();
+            let all_entries = [];
+            while (true) {
+                let entries = await new Promise((res, rej) => reader.readEntries(res, rej));
+                all_entries.push.apply(all_entries, entries);
+                if (entries.length === 0)
+                    break;
+            }
+
+            await handle_entries(all_entries, dir_prefix);
+        };
+        let handle_entries = (entries, dir_prefix) => {
+            file_count += entries.length;
+            if (file_count > 4096)
+                throw new LLError("Found way too many files; did you drag in the wrong directory?");
+
+            let dir_promises = [];
+            for (let entry of entries) {
+                if (entry.isDirectory) {
+                    dir_promises.push(read_directory(entry, dir_prefix + entry.name + '/'));
+                }
+                else {
+                    this.files[(dir_prefix + entry.name).toLowerCase()] = entry;
+                }
+            }
+
+            return Promise.all(dir_promises);
+        };
+
+        this._loaded_promise = handle_entries(entries, '');
+    }
+
+    async get(path) {
+        let entry = this.files[path.toLowerCase()];
+        if (! entry)
+            throw new LLError(`No such file in local directory: ${path}`);
+
+        let file = await new Promise((res, rej) => entry.file(res, rej));
+        return await file.arrayBuffer();
+    }
+}

style.css

@@ -82,6 +82,12 @@ p:first-child {
 p:last-child {
     margin-bottom: 0;
 }
+pre {
+    white-space: pre-wrap;
+}
+code {
+    color: #c0c0e0;
+}
 
 a {
     color: #c0c0c0;
@@ -154,6 +160,11 @@ a:active {
     overflow: auto;
     padding: 1em;
 }
+.dialog pre.error {
+    color: #400000;
+    background: #f0d0d0;
+    padding: 0.5em 1em;
+}
 
 /* Individual overlays */
 table.level-browser {
@@ -188,6 +199,10 @@ table.level-browser tr.--unvisited {
     color: #606060;
     font-style: italic;
 }
+table.level-browser tr.--error {
+    color: #600000;
+    font-style: italic;
+}
 table.level-browser tbody tr {
     cursor: pointer;
 }
@@ -350,10 +365,31 @@ body[data-mode=player] #editor-play {
     ;
     gap: 1em;
 
+    position: relative;
     padding: 1em 10%;
     margin: auto;
     overflow: auto;
 }
+#splash > .drag-overlay {
+    display: none;
+    justify-content: center;
+    align-items: center;
+
+    font-size: 10vmin;
+    position: absolute;
+    top: 0;
+    bottom: 0;
+    left: 1rem;
+    right: 1rem;
+    background: #fff2;
+    border: 0.25rem dashed white;
+    border-radius: 1rem;
+    text-shadow: 0 1px 5px black;
+    text-align: center;
+}
+#splash.--drag-hover > .drag-overlay {
+    display: flex;
+}
 
 #splash > header {
     grid-area: header;
@@ -387,7 +423,8 @@ body[data-mode=player] #editor-play {
 #splash > #splash-upload-levels {
     grid-area: upload;
 }
-#splash-upload {
+#splash-upload-file,
+#splash-upload-dir {
     /* Hide the file upload control, which is ugly */
     display: none;
 }