Remove savegame object compression

Preparation for further changes. Savegames that are not compressed are
much bigger, but this is a rather complex algorithm that shouldn't
exist.

src/js/core/read_write_proxy.js

@@ -3,7 +3,6 @@ import { Application } from "../application";
 /* typehints:end */
 
 import { FsError } from "@/platform/fs_error";
-import { compressObject, decompressObject } from "../savegame/savegame_compressor";
 import { asyncCompressor, compressionPrefix } from "./async_compression";
 import { IS_DEBUG, globalConfig } from "./config";
 import { ExplainedResult } from "./explained_result";
@@ -85,7 +84,7 @@ export class ReadWriteProxy {
      * @param {object} obj
      */
     static serializeObject(obj) {
-        const jsonString = JSON.stringify(compressObject(obj));
+        const jsonString = JSON.stringify(obj);
         const checksum = computeCrc(jsonString + salt);
         return compressionPrefix + compressX64(checksum + jsonString);
     }
@@ -117,8 +116,7 @@ export class ReadWriteProxy {
         }
 
         const parsed = JSON.parse(jsonString);
-        const decoded = decompressObject(parsed);
-        return decoded;
+        return parsed;
     }
 
     /**
@@ -180,7 +178,7 @@ export class ReadWriteProxy {
                 .then(rawData => {
                     if (rawData == null) {
                         // So, the file has not been found, use default data
-                        return JSON.stringify(compressObject(this.getDefaultData()));
+                        return JSON.stringify(this.getDefaultData());
                     }
 
                     if (rawData.startsWith(compressionPrefix)) {
@@ -233,9 +231,6 @@ export class ReadWriteProxy {
                     }
                 })
 
-                // Decompress
-                .then(compressed => decompressObject(compressed))
-
                 // Verify basic structure
                 .then(contents => {
                     const result = this.internalVerifyBasicStructure(contents);

src/js/savegame/savegame_compressor.js

@@ -1,168 +0,0 @@
-const charmap =
-    "!#%&'()*+,-./:;<=>?@[]^_`{|}~¥¦§¨©ª«¬­®¯°±²³´µ¶·¸¹º»¼½¾¿ÀÁÂÃÄÅÆÇÈÉÊËÌÍÎÏÐÑÒÓÔÕÖ×ØÙÚÛÜÝÞßàáâãäåæçèéêëìíîïðñòóôõö÷øùúûüýþÿABCDEFGHIJKLMNOPQRSTUVWXYZ";
-
-let compressionCache = {};
-let decompressionCache = {};
-
-/**
- * Compresses an integer into a tight string representation
- * @param {number} i
- * @returns {string}
- */
-function compressInt(i) {
-    // Zero value breaks
-    i += 1;
-
-    // save `i` as the cache key
-    // to avoid it being modified by the
-    // rest of the function.
-    const cache_key = i;
-
-    if (compressionCache[cache_key]) {
-        return compressionCache[cache_key];
-    }
-    let result = "";
-    do {
-        result += charmap[i % charmap.length];
-        i = Math.floor(i / charmap.length);
-    } while (i > 0);
-    return (compressionCache[cache_key] = result);
-}
-
-/**
- * Decompresses an integer from its tight string representation
- * @param {string} s
- * @returns {number}
- */
-function decompressInt(s) {
-    if (decompressionCache[s]) {
-        return decompressionCache[s];
-    }
-    s = "" + s;
-    let result = 0;
-    for (let i = s.length - 1; i >= 0; --i) {
-        result = result * charmap.length + charmap.indexOf(s.charAt(i));
-    }
-    // Fixes zero value break fix from above
-    result -= 1;
-    return (decompressionCache[s] = result);
-}
-
-// Sanity
-if (G_IS_DEV) {
-    for (let i = 0; i < 10000; ++i) {
-        if (decompressInt(compressInt(i)) !== i) {
-            throw new Error(
-                "Bad compression for: " +
-                    i +
-                    " compressed: " +
-                    compressInt(i) +
-                    " decompressed: " +
-                    decompressInt(compressInt(i))
-            );
-        }
-    }
-}
-
-/**
- * @param {any} obj
- * @param {Map} keys
- * @param {Map} values
- * @returns {any[]|object|number|string}
- */
-function compressObjectInternal(obj, keys, values) {
-    if (Array.isArray(obj)) {
-        let result = [];
-        for (let i = 0; i < obj.length; ++i) {
-            result.push(compressObjectInternal(obj[i], keys, values));
-        }
-        return result;
-    } else if (typeof obj === "object" && obj !== null) {
-        let result = {};
-        for (const key in obj) {
-            let index = keys.get(key);
-            if (index === undefined) {
-                index = keys.size;
-                keys.set(key, index);
-            }
-            const value = obj[key];
-            result[compressInt(index)] = compressObjectInternal(value, keys, values);
-        }
-        return result;
-    } else if (typeof obj === "string") {
-        let index = values.get(obj);
-        if (index === undefined) {
-            index = values.size;
-            values.set(obj, index);
-        }
-        return compressInt(index);
-    }
-    return obj;
-}
-
-/**
- * @param {Map} hashMap
- * @returns {Array}
- */
-function indexMapToArray(hashMap) {
-    const result = new Array(hashMap.size);
-    hashMap.forEach((index, key) => {
-        result[index] = key;
-    });
-    return result;
-}
-
-/**
- * @param {object} obj
- */
-export function compressObject(obj) {
-    const keys = new Map();
-    const values = new Map();
-    const data = compressObjectInternal(obj, keys, values);
-    return {
-        keys: indexMapToArray(keys),
-        values: indexMapToArray(values),
-        data,
-    };
-}
-
-/**
- * @param {object} obj
- * @param {string[]} keys
- * @param {any[]} values
- * @returns {object}
- */
-function decompressObjectInternal(obj, keys = [], values = []) {
-    if (Array.isArray(obj)) {
-        let result = [];
-        for (let i = 0; i < obj.length; ++i) {
-            result.push(decompressObjectInternal(obj[i], keys, values));
-        }
-        return result;
-    } else if (typeof obj === "object" && obj !== null) {
-        let result = {};
-        for (const key in obj) {
-            const realIndex = decompressInt(key);
-            const value = obj[key];
-            result[keys[realIndex]] = decompressObjectInternal(value, keys, values);
-        }
-        return result;
-    } else if (typeof obj === "string") {
-        const realIndex = decompressInt(obj);
-        return values[realIndex];
-    }
-    return obj;
-}
-
-/**
- * @param {object} obj
- */
-export function decompressObject(obj) {
-    if (obj.keys && obj.values && obj.data) {
-        const keys = obj.keys;
-        const values = obj.values;
-        const result = decompressObjectInternal(obj.data, keys, values);
-        return result;
-    }
-    return obj;
-}

src/js/webworkers/compression.worker.js

@@ -1,7 +1,6 @@
 import { globalConfig } from "../core/config";
 import { compressX64 } from "../core/lzstring";
 import { computeCrc } from "../core/sensitive_utils.encrypt";
-import { compressObject } from "../savegame/savegame_compressor";
 
 self.addEventListener("message", event => {
     // @ts-ignore
@@ -19,8 +18,7 @@ function performJob(job, data) {
         }
 
         case "compressObject": {
-            const optimized = compressObject(data.obj);
-            const stringified = JSON.stringify(optimized);
+            const stringified = JSON.stringify(data.obj);
 
             const checksum = computeCrc(stringified + globalConfig.info.file);
             return data.compressionPrefix + compressX64(checksum + stringified);