client/src/utils/gameStorage.js

   1 // Game object: {
   2 //   // Static informations:
   3 //   id: string
   4 //   vname: string,
   5 //   fenStart: string,
   6 //   players: array of sid+id+name,
   7 //   cadence: string,
   8 //   increment: integer (seconds),
   9 //   type: string ("live" or "corr")
  10 //   // Game (dynamic) state:
  11 //   fen: string,
  12 //   moves: array of Move objects,
  13 //   clocks: array of integers,
  14 //   initime: array of integers (when clock start running),
  15 //   score: string (several options; '*' == running),
  16 // }
  17
  18 import { store } from "@/store";
  19
  20 function dbOperation(callback) {
  21   let db = null;
  22   let DBOpenRequest = window.indexedDB.open("vchess", 5);
  23
  24   DBOpenRequest.onerror = function(event) {
  25     alert(store.state.tr["Database error: stop private browsing, or update your browser"]);
  26     callback("error", null);
  27   };
  28
  29   DBOpenRequest.onsuccess = function() {
  30     db = DBOpenRequest.result;
  31     callback(null, db);
  32     db.close();
  33   };
  34
  35   DBOpenRequest.onupgradeneeded = function(event) {
  36     let db = event.target.result;
  37     let upgradeTransaction = event.target.transaction;
  38     let objectStore = undefined;
  39     if (!db.objectStoreNames.contains("games"))
  40       objectStore = db.createObjectStore("games", { keyPath: "id" });
  41     else
  42       objectStore = upgradeTransaction.objectStore("games");
  43     if (!objectStore.indexNames.contains("score"))
  44       // To sarch games by score (useful for running games)
  45       objectStore.createIndex("score", "score", { unique: false });
  46     if (!objectStore.indexNames.contains("created"))
  47       // To search by date intervals. Two games cannot start at the same time
  48       objectStore.createIndex("created", "created", { unique: true });
  49   };
  50 }
  51
  52 export const GameStorage = {
  53   // Optional callback to get error status
  54   add: function(game, callback) {
  55     dbOperation((err,db) => {
  56       if (!!err) {
  57         callback("error");
  58         return;
  59       }
  60       let transaction = db.transaction("games", "readwrite");
  61       transaction.oncomplete = function() {
  62         // Everything's fine
  63         callback();
  64       };
  65       transaction.onerror = function(err) {
  66         // Duplicate key error (most likely)
  67         callback(err);
  68       };
  69       transaction.objectStore("games").add(game);
  70     });
  71   },
  72
  73   // obj: chat, move, fen, clocks, score[Msg], initime, ...
  74   update: function(gameId, obj) {
  75     // live
  76     dbOperation((err,db) => {
  77       let objectStore = db
  78         .transaction("games", "readwrite")
  79         .objectStore("games");
  80       objectStore.get(gameId).onsuccess = function(event) {
  81         // Ignoring error silently: shouldn't happen now. TODO?
  82         if (event.target.result) {
  83           let game = event.target.result;
  84           // Hidden tabs are delayed, to prevent multi-updates:
  85           if (obj.moveIdx < game.moves.length) return;
  86           Object.keys(obj).forEach(k => {
  87             if (k == "move") game.moves.push(obj[k]);
  88             else if (k == "chat") game.chats.push(obj[k]);
  89             else if (k == "delchat") game.chats = [];
  90             else game[k] = obj[k];
  91           });
  92           objectStore.put(game); //save updated data
  93         }
  94       };
  95     });
  96   },
  97
  98   // Retrieve (all) running local games
  99   getRunning: function(callback) {
 100     dbOperation((err,db) => {
 101       let objectStore = db
 102         .transaction("games", "readonly")
 103         .objectStore("games");
 104       let index = objectStore.index("score");
 105       const range = IDBKeyRange.only("*");
 106       let games = [];
 107       index.openCursor(range).onsuccess = function(event) {
 108         let cursor = event.target.result;
 109         if (!cursor) callback(games);
 110         else {
 111           // If there is still another cursor to go, keep running this code
 112           let g = cursor.value;
 113           // Do not retrieve moves or clocks (unused in list mode)
 114           g.movesCount = g.moves.length;
 115           delete g.moves;
 116           delete g.clocks;
 117           delete g.initime;
 118           games.push(g);
 119           cursor.continue();
 120         }
 121       };
 122     });
 123   },
 124
 125   // Retrieve completed local games
 126   getNext: function(upperDt, callback) {
 127     dbOperation((err,db) => {
 128       let objectStore = db
 129         .transaction("games", "readonly")
 130         .objectStore("games");
 131       let index = objectStore.index("created");
 132       const range = IDBKeyRange.upperBound(upperDt);
 133       let games = [];
 134       index.openCursor(range).onsuccess = function(event) {
 135         let cursor = event.target.result;
 136         if (!cursor) {
 137           // Most recent games first:
 138           games = games.sort((g1, g2) => g2.created - g1.created);
 139           // TODO: 20 games showed per request is arbitrary
 140           callback(games.slice(0, 20));
 141         }
 142         else {
 143           // If there is still another cursor to go, keep running this code
 144           let g = cursor.value;
 145           if (g.score != "*") {
 146             // Do not retrieve moves or clocks (unused in list mode)
 147             g.movesCount = g.moves.length;
 148             delete g.moves;
 149             delete g.clocks;
 150             delete g.initime;
 151             games.push(g);
 152           }
 153           cursor.continue();
 154         }
 155       };
 156     });
 157   },
 158
 159   // Retrieve any game from its identifiers (locally or on server)
 160   // NOTE: need callback because result is obtained asynchronously
 161   get: function(gameId, callback) {
 162     // Local game
 163     dbOperation((err,db) => {
 164       let objectStore = db.transaction("games").objectStore("games");
 165       objectStore.get(gameId).onsuccess = function(event) {
 166         // event.target.result is null if game not found
 167         callback(event.target.result);
 168       };
 169     });
 170   },
 171
 172   // Delete a game in indexedDB
 173   remove: function(gameId, callback) {
 174     dbOperation((err,db) => {
 175       if (!err) {
 176         let transaction = db.transaction("games", "readwrite");
 177         transaction.oncomplete = function() {
 178           callback(); //everything's fine
 179         };
 180         transaction.objectStore("games").delete(gameId);
 181       }
 182     });
 183   }
 184 };