1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
|
<!doctype html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport"
content="width=device-width, user-scalable=no, initial-scale=1.0, maximum-scale=1.0, minimum-scale=1.0">
<meta http-equiv="X-UA-Compatible" content="ie=edge">
<title>Awesome Chess</title>
</head>
<style>
* {
padding: 0;
margin: 0;
box-sizing: border-box;
}
#app {
margin: 0 auto;
width: fit-content;
}
.board {
border: 2px solid black;
font-size: 20px;
user-select: none;
}
.board-field.black {
background: chocolate;
}
.board-field.white {
background: bisque;
}
.board-field {
text-align: center;
width: 1.5em;
border: 1px transparent;
height: 1.5em;
}
.lastmove {
border: 1px solid green;
}
#warn {
display: block;
position: fixed;
top: 25%;
left: 25%;
z-index: 10;
margin: 0 auto;
width: 50%;
background: coral;
border: crimson solid 1px;
}
.status {
text-align: center;
font-family: sans-serif;
}
.invisible {
display: none !important;
}
a, a:hover, a:focus, a:visited, a:active {
color: inherit;
}
</style>
<body>
<div id="app">
<p class="status">You are <b>white</b></p>
</div>
<div id="warn" class="invisible">
Connection closed
</div>
<script>
class Board {
constructor(elem) {
this.socket = new WebSocket(`${location.protocol.includes('s') ? 'wss' : 'ws'}://${window.location.host}/socket`)
this.ended = false
this.boardState = {}
this.lastMove = ''
window.addEventListener('beforeunload', () => {
this.ended = true
})
this.socket.addEventListener('message', ev => {
const message = JSON.parse(ev.data)
console.log(message)
this.playerColor = message.player_color || this.playerColor
this.boardState = parseFEN(message.board)
this.lastMove = message.lastmove || ''
this.ended ||= message.event === 'game_over'
this.result = message.result
this.synchronizeBoard()
})
this.socket.addEventListener('close', () => {
if (!this.ended)
document.getElementById('warn').classList.remove('invisible')
})
let board = document.createElement("table")
board.className = "board"
this.fields = {};
for (let i = 7; i >= 0; i--) {
let row = document.createElement("tr")
row.className = "board-row"
for (let j = 0; j < 8; j++) {
let field = document.createElement("td")
field.className = "board-field " + (((i + j) % 2) === 0 ? 'black' : 'white');
let name = indiciesToFieldName(i, j)
field.innerText = name;
field.addEventListener("dragover", ev => ev.preventDefault())
field.addEventListener("drop", ev => {
ev.preventDefault()
this.playMove(ev.dataTransfer.getData("text"), name)
})
this.fields [name] = field
row.appendChild(field)
}
board.appendChild(row)
}
elem.appendChild(board)
this.turnIndicator = document.createElement('p')
this.turnIndicator.className = "turn-indicator status"
elem.appendChild(this.turnIndicator)
}
playMove(fromField, toField) {
if (!this.isPlayerTurn) return
let uci = fromField + toField
if (((toField[1] === '8' && this.playerColor === 'white')
|| (toField[2] === '1' && this.playerColor === 'black'))
&& (this.boardState[fromField].toUpperCase() === 'P')) {
uci += window.prompt('promote to what')
}
this.socket.send(JSON.stringify({
method: "move",
params: {
move: uci
}
}))
}
get canPlay() {
return this.isPlayerTurn && !this.ended
}
get isPlayerTurn() {
return this.playerColor === this.boardState.turn
}
synchronizeBoard() {
this.turnIndicator.innerHTML = `<b>${capitalize(this.boardState.turn)}</b>s turn`
if (this.ended) {
this.turnIndicator.innerHTML += `
<p><a href="https://youtu.be/yIRT6xRQkf8"><b>${this.result}</b></a></p>
`
}
for (let field in this.fields) {
const fieldDOM = this.fields[field]
fieldDOM.innerHTML = ""
if (this.boardState[field]) {
let piece = document.createElement("span")
piece.innerText = notationToPieceUnicode(this.boardState[field])
piece.addEventListener("dragstart", ev => {
ev.dataTransfer.setData("text", field)
})
piece.draggable = this.canPlay
fieldDOM.appendChild(piece)
}
fieldDOM.classList.remove('lastmove')
if (this.lastMove.includes(field)) {
fieldDOM.classList.add('lastmove')
}
}
}
}
function capitalize(thing) {
return thing.replace(/\b./, x => x.toUpperCase())
}
function indiciesToFieldName(row, col) {
return "abcdefgh".at(col) + (row + 1)
}
function parseFEN(notation) {
let row = 7;
let col = 0;
let board = {}
let s = 'position'
let error = c => {
console.log("Error while parsing notation")
console.log(board)
throw "Could not parse notation: " + c
}
for (let c of notation) {
if (s === 'position') {
if (c === '/') { // Next row on /
if (col !== 8) {
throw "Row not finished"
}
row--
col = 0
} else if ((c | 0) > 0) { // Skip n places on a number
col += (c | 0)
} else if (c === ' ') {
s = 'turn'
} else if ("KQRBNP".includes(c.toUpperCase())) {
board[indiciesToFieldName(row, col)] = c
col += 1
} else {
error(c)
}
} else if (s === 'turn') {
if (c === 'b') {
board.turn = 'black'
} else if (c === 'w') {
board.turn = 'white'
} else if (c === ' ') {
break
} else {
error(c)
}
} else {
error('Invalid state ' + s)
}
}
return board
}
function notationToPieceUnicode(notation) {
let white = "♔♕♖♗♘♙"
let black = "♚♛♜♝♞♟︎"
let names = "KQRBNP"
let index = names.indexOf(notation.toUpperCase())
if (index < 0) {
return null
}
return (notation < 'Z' ? white : black)[index];
}
const board = new Board(document.getElementById("app"));
</script>
</body>
</html>
|
