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", 4);
  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 game[k] = obj[k];
  89           });
  90           objectStore.put(game); //save updated data
  91         }
  92       };
  93     });
  94   },
  95
  96   // Retrieve (all) running local games
  97   getRunning: function(callback) {
  98     dbOperation((err,db) => {
  99       let objectStore = db
 100         .transaction("games", "readonly")
 101         .objectStore("games");
 102       let index = objectStore.index("score");
 103       const range = IDBKeyRange.only("*");
 104       let games = [];
 105       index.openCursor(range).onsuccess = function(event) {
 106         let cursor = event.target.result;
 107         if (!cursor) callback(games);
 108         else {
 109           // If there is still another cursor to go, keep running this code
 110           let g = cursor.value;
 111           // Do not retrieve moves or clocks (unused in list mode)
 112           g.movesCount = g.moves.length;
 113           delete g.moves;
 114           delete g.clocks;
 115           delete g.initime;
 116           games.push(g);
 117           cursor.continue();
 118         }
 119       };
 120     });
 121   },
 122
 123   // Retrieve completed local games
 124   getNext: function(upperDt, callback) {
 125     dbOperation((err,db) => {
 126       let objectStore = db
 127         .transaction("games", "readonly")
 128         .objectStore("games");
 129       let index = objectStore.index("created");
 130       const range = IDBKeyRange.upperBound(upperDt);
 131       let games = [];
 132       index.openCursor(range).onsuccess = function(event) {
 133         let cursor = event.target.result;
 134         if (!cursor) {
 135           // Most recent games first:
 136           games = games.sort((g1, g2) => g2.created - g1.created);
 137           // TODO: 20 games showed per request is arbitrary
 138           callback(games.slice(0, 20));
 139         }
 140         else {
 141           // If there is still another cursor to go, keep running this code
 142           let g = cursor.value;
 143           if (g.score != "*") {
 144             // Do not retrieve moves or clocks (unused in list mode)
 145             g.movesCount = g.moves.length;
 146             delete g.moves;
 147             delete g.clocks;
 148             delete g.initime;
 149             games.push(g);
 150           }
 151           cursor.continue();
 152         }
 153       };
 154     });
 155   },
 156
 157   // Retrieve any game from its identifiers (locally or on server)
 158   // NOTE: need callback because result is obtained asynchronously
 159   get: function(gameId, callback) {
 160     // Local game
 161     dbOperation((err,db) => {
 162       let objectStore = db.transaction("games").objectStore("games");
 163       objectStore.get(gameId).onsuccess = function(event) {
 164         // event.target.result is null if game not found
 165         callback(event.target.result);
 166       };
 167     });
 168   },
 169
 170   // Delete a game in indexedDB
 171   remove: function(gameId, callback) {
 172     dbOperation((err,db) => {
 173       if (!err) {
 174         let transaction = db.transaction("games", "readwrite");
 175         transaction.oncomplete = function() {
 176           callback(); //everything's fine
 177         };
 178         transaction.objectStore("games").delete(gameId);
 179       }
 180     });
 181   }
 182 };