๐Ÿ“ฆ toeverything / AFFiNE

๐Ÿ“„ index.ts ยท 181 lines
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
181import { readFileSync, writeFileSync } from 'node:fs';

import {
  applyUpdate,
  Doc,
  encodeStateAsUpdate,
  encodeStateVector,
  UndoManager,
} from 'yjs';

type InputFormat = 'file' | 'base64' | 'hex';
type OutputFormat = 'bin' | 'base64' | 'hex';

const HELP_TEXT = `
Generate a revert update from two Yjs snapshot binaries.

Usage:
  r ./tools/revert-update/index.ts --from <value> --to <value> [options]

Options:
  --from <value>         Newer snapshot input (path/base64/hex)
  --to <value>           Older snapshot input (path/base64/hex)
  --from-format <fmt>    file|base64|hex (default: file)
  --to-format <fmt>      file|base64|hex (default: file)
  --out <path>           Output path (default: stdout)
  --out-format <fmt>     bin|base64|hex (default: base64 if stdout, bin if file)
  -h, --help             Show help

Examples:
  r ./tools/revert-update/index.ts --from ./from.bin --to ./to.bin --out ./revert.bin
  r ./tools/revert-update/index.ts --from "$FROM" --from-format base64 --to "$TO" --to-format base64
`;

function generateRevertUpdate(
  fromNewerBin: Uint8Array,
  toOlderBin: Uint8Array
): Uint8Array {
  const newerDoc = new Doc();
  applyUpdate(newerDoc, fromNewerBin);
  const olderDoc = new Doc();
  applyUpdate(olderDoc, toOlderBin);

  const newerState = encodeStateVector(newerDoc);
  const olderState = encodeStateVector(olderDoc);

  const diff = encodeStateAsUpdate(newerDoc, olderState);
  const undoManager = new UndoManager(Array.from(olderDoc.share.values()));

  applyUpdate(olderDoc, diff);
  undoManager.undo();

  return encodeStateAsUpdate(olderDoc, newerState);
}

function fail(message: string): never {
  console.error(message);
  console.error(HELP_TEXT.trim());
  process.exit(1);
}

function parseInputFormat(value: string, flag: string): InputFormat {
  switch (value) {
    case 'file':
    case 'base64':
    case 'hex':
      return value;
    default:
      fail(`Unknown ${flag} value: ${value}`);
  }
}

function parseOutputFormat(value: string, flag: string): OutputFormat {
  switch (value) {
    case 'bin':
    case 'base64':
    case 'hex':
      return value;
    default:
      fail(`Unknown ${flag} value: ${value}`);
  }
}

function parseArgs(argv: string[]) {
  const args = new Map<string, string>();
  for (let i = 0; i < argv.length; i += 1) {
    const arg = argv[i];
    if (arg === '--help' || arg === '-h') {
      console.log(HELP_TEXT.trim());
      process.exit(0);
    }
    if (!arg.startsWith('--')) {
      fail(`Unknown argument: ${arg}`);
    }
    const value = argv[i + 1];
    if (!value || value.startsWith('--')) {
      fail(`Missing value for ${arg}`);
    }
    args.set(arg, value);
    i += 1;
  }

  const from = args.get('--from');
  const to = args.get('--to');
  if (!from || !to) {
    fail('Both --from and --to are required.');
  }

  const fromFormat = parseInputFormat(
    (args.get('--from-format') ?? 'file').toLowerCase(),
    '--from-format'
  );
  const toFormat = parseInputFormat(
    (args.get('--to-format') ?? 'file').toLowerCase(),
    '--to-format'
  );

  const outPath = args.get('--out');
  const defaultOutFormat = outPath ? 'bin' : 'base64';
  const outFormat = parseOutputFormat(
    (args.get('--out-format') ?? defaultOutFormat).toLowerCase(),
    '--out-format'
  );

  return {
    from,
    to,
    fromFormat,
    toFormat,
    outPath,
    outFormat,
  };
}

function readInput(value: string, format: InputFormat): Uint8Array {
  try {
    if (format === 'file') {
      return new Uint8Array(readFileSync(value));
    }
    const trimmed = value.trim();
    const decoded = Buffer.from(trimmed, format === 'hex' ? 'hex' : 'base64');
    return new Uint8Array(decoded);
  } catch (error) {
    const details = error instanceof Error ? error.message : String(error);
    fail(`Failed to read ${format} input: ${details}`);
  }
}

function writeOutput(
  update: Uint8Array,
  outPath: string | undefined,
  format: OutputFormat
) {
  if (outPath) {
    if (format === 'bin') {
      writeFileSync(outPath, update);
      return;
    }
    const encoded = Buffer.from(update).toString(format);
    writeFileSync(outPath, encoded);
    return;
  }

  if (format === 'bin') {
    process.stdout.write(Buffer.from(update));
    return;
  }
  const encoded = Buffer.from(update).toString(format);
  process.stdout.write(`${encoded}\n`);
}

const { from, to, fromFormat, toFormat, outPath, outFormat } = parseArgs(
  process.argv.slice(2)
);

const fromBin = readInput(from, fromFormat);
const toBin = readInput(to, toFormat);

const revertUpdate = generateRevertUpdate(fromBin, toBin);

writeOutput(revertUpdate, outPath, outFormat);