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 objectStore = db.createObjectStore("games", { keyPath: "id" });
  38     objectStore.createIndex("score", "score"); //to search by game result
  39   };
  40 }
  41
  42 export const GameStorage = {
  43   // Optional callback to get error status
  44   add: function(game, callback) {
  45     dbOperation((err,db) => {
  46       if (err) {
  47         callback("error");
  48         return;
  49       }
  50       let transaction = db.transaction("games", "readwrite");
  51       transaction.oncomplete = function() {
  52         callback(); //everything's fine
  53       };
  54       let objectStore = transaction.objectStore("games");
  55       objectStore.add(game);
  56     });
  57   },
  58
  59   // obj: chat, move, fen, clocks, score[Msg], initime, ...
  60   update: function(gameId, obj) {
  61     // live
  62     dbOperation((err,db) => {
  63       let objectStore = db
  64         .transaction("games", "readwrite")
  65         .objectStore("games");
  66       objectStore.get(gameId).onsuccess = function(event) {
  67         // Ignoring error silently: shouldn't happen now. TODO?
  68         if (event.target.result) {
  69           let game = event.target.result;
  70           // Hidden tabs are delayed, to prevent multi-updates:
  71           if (obj.moveIdx < game.moves.length) return;
  72           Object.keys(obj).forEach(k => {
  73             if (k == "move") game.moves.push(obj[k]);
  74             else game[k] = obj[k];
  75           });
  76           objectStore.put(game); //save updated data
  77         }
  78       };
  79     });
  80   },
  81
  82   // Retrieve all local games (running, completed, imported...)
  83   // light: do not retrieve moves or clocks (TODO: this is the only usage)
  84   getAll: function(light, callback) {
  85     dbOperation((err,db) => {
  86       let objectStore = db.transaction("games").objectStore("games");
  87       let games = [];
  88       objectStore.openCursor().onsuccess = function(event) {
  89         let cursor = event.target.result;
  90         // if there is still another cursor to go, keep running this code
  91         if (cursor) {
  92           let g = cursor.value;
  93           if (light) {
  94             g.movesCount = g.moves.length;
  95             delete g.moves;
  96             delete g.clocks;
  97             delete g.initime;
  98           }
  99           games.push(g);
 100           cursor.continue();
 101         } else callback(games);
 102       };
 103     });
 104   },
 105
 106   // Retrieve any game from its identifiers (locally or on server)
 107   // NOTE: need callback because result is obtained asynchronously
 108   get: function(gameId, callback) {
 109     // Local game
 110     dbOperation((err,db) => {
 111       let objectStore = db.transaction("games").objectStore("games");
 112       objectStore.get(gameId).onsuccess = function(event) {
 113         if (event.target.result)
 114           callback(event.target.result);
 115       };
 116     });
 117   },
 118
 119   // Delete a game in indexedDB
 120   remove: function(gameId, callback) {
 121     dbOperation((err,db) => {
 122       if (!err) {
 123         let transaction = db.transaction(["games"], "readwrite");
 124         transaction.oncomplete = function() {
 125           callback(); //everything's fine
 126         };
 127         transaction.objectStore("games").delete(gameId);
 128       }
 129     });
 130   }
 131 };