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       transaction.onerror = function(err) {
  55         callback(err); //duplicate key error (most likely)
  56       };
  57       let objectStore = transaction.objectStore("games");
  58       objectStore.add(game);
  59     });
  60   },
  61
  62   // obj: chat, move, fen, clocks, score[Msg], initime, ...
  63   update: function(gameId, obj) {
  64     // live
  65     dbOperation((err,db) => {
  66       let objectStore = db
  67         .transaction("games", "readwrite")
  68         .objectStore("games");
  69       objectStore.get(gameId).onsuccess = function(event) {
  70         // Ignoring error silently: shouldn't happen now. TODO?
  71         if (event.target.result) {
  72           let game = event.target.result;
  73           // Hidden tabs are delayed, to prevent multi-updates:
  74           if (obj.moveIdx < game.moves.length) return;
  75           Object.keys(obj).forEach(k => {
  76             if (k == "move") game.moves.push(obj[k]);
  77             else game[k] = obj[k];
  78           });
  79           objectStore.put(game); //save updated data
  80         }
  81       };
  82     });
  83   },
  84
  85   // Retrieve all local games (running, completed, imported...)
  86   // light: do not retrieve moves or clocks (TODO: this is the only usage)
  87   getAll: function(light, callback) {
  88     dbOperation((err,db) => {
  89       let objectStore = db.transaction("games").objectStore("games");
  90       let games = [];
  91       objectStore.openCursor().onsuccess = function(event) {
  92         let cursor = event.target.result;
  93         // if there is still another cursor to go, keep running this code
  94         if (cursor) {
  95           let g = cursor.value;
  96           if (light) {
  97             g.movesCount = g.moves.length;
  98             delete g.moves;
  99             delete g.clocks;
 100             delete g.initime;
 101           }
 102           games.push(g);
 103           cursor.continue();
 104         } else callback(games);
 105       };
 106     });
 107   },
 108
 109   // Retrieve any game from its identifiers (locally or on server)
 110   // NOTE: need callback because result is obtained asynchronously
 111   get: function(gameId, callback) {
 112     // Local game
 113     dbOperation((err,db) => {
 114       let objectStore = db.transaction("games").objectStore("games");
 115       objectStore.get(gameId).onsuccess = function(event) {
 116         if (event.target.result)
 117           callback(event.target.result);
 118       };
 119     });
 120   },
 121
 122   // Delete a game in indexedDB
 123   remove: function(gameId, callback) {
 124     dbOperation((err,db) => {
 125       if (!err) {
 126         let transaction = db.transaction(["games"], "readwrite");
 127         transaction.oncomplete = function() {
 128           callback(); //everything's fine
 129         };
 130         transaction.objectStore("games").delete(gameId);
 131       }
 132     });
 133   }
 134 };