npm install text-version // or
pnpm install text-version // or
yarn add text-version

// ES6 modules
import { TextVersion } from 'text-version';

// CommonJS
const { TextVersion } = require('text-version');

const tv = new TextVersion();

// Import
import { TextVersion } from 'text-version';
// Or CommonJS
// const { TextVersion } = require('text-version');

// Create instance
const tv = new TextVersion();

// Submit new version
tv.commit('Hello, World!', 'v1');
tv.commit('Hello, World!\\nThis is the second line.', 'v2');
tv.commit('Hello, TypeScript!\\nThis is the second line.');

// View version history
console.log(tv.log());
//[
//  { version: 'v1', isSnapshot: false },  // diff
//  { version: 'v2', isSnapshot: false },  // diff
//  { version: 'ycdf93', isSnapshot: true } // snapshot (latest)
//]

// View specified version
console.log(tv.show('v1')); 
// "Hello, World!"

// View latest version
console.log(tv.latest());
// "Hello, TypeScript!\\nThis is the second line."

// Export version data (monolithic mode - default)
const storage = tv.export();
// Or explicitly specify monolithic mode
const storage2 = tv.export("monolithic");
console.log(storage);
// 2:v1:R6D7
// 2:v2:R3D10I2:world
// :6:ycdf93:hello, TypeScript！\nThis is the second line.

// Reset to specified version
tv.reset('v2');

// Compress storage space - set v2 as snapshot, delete v1
tv.squash('v2'); // v1 version will be permanently deleted, v2 becomes new starting snapshot

// Load from existing storage
const tv2 = new TextVersion(storage);
console.log(tv2.latest()); // Can access the saved data

const tv = new TextVersion();

// Create multiple versions
tv.commit('First version', 'v1');
tv.commit('Second version', 'v2');
tv.commit('Third version', 'v3');
tv.commit('Fourth version', 'v4');

const storage = tv.export();
console.log('Original storage size:', storage.length);
console.log('Version count:', tv.log().length); // 4 versions

// Compress to v2, delete v1
tv.squash('v2');

const newStorage = tv.export();
console.log('Compressed storage size:', newStorage.length);
console.log('Version count:', tv.log().length); // 3 versions: v2, v3, v4

// v1 version has been deleted and cannot be accessed
console.log(tv.show('v1')); // null

// v2 and later versions can still be accessed normally
console.log(tv.show('v2')); // "Second version"

// Note: After squash, v4 (latest version) is a snapshot, v2 and v3 are diffs

:version_name_length:version_name:content         (snapshot version)
version_name_length:version_name:operation_sequence      (diff version)
version_name_length:version_name:=version_name       (version reference)
version_name_length:version_name:=version_name:operation_sequence  (hybrid reference)

2:v1:R8D8I13:original text  # v1 is reverse diff (from v2 to v1)
2:v2:R4I8:modified content D2  # v2 is reverse diff (from v3 to v2)
:2:v3:This is latest modified content  # v3 is snapshot (latest version)
2:v1#:=v1  # Reference to v1

import { TextVersion } from 'text-version';

// Compression usage example
const compressionProvider = {
  compress: (data) => /* compression algorithm */ data,
  decompress: (data) => /* decompression algorithm */ data
};

const tv = new TextVersion('', compressionProvider);
tv.commit('This is a very long text...');
console.log(tv.latest());

const tv = new TextVersion();
tv.commit('First version', 'v1');
tv.commit('Second version', 'v2');
tv.commit('Very very very long latest version content...', 'v3');

// Separate export
const result = tv.export("separate");
// result = {
//   metadata: "2:v1:D6I4:original text\n2:v2:D5\n:2:v3:##[[abc12345]]##",
//   snapshot: "Very very very long latest version content..."
// }
// Note: ##[[abc12345]]## is a hash placeholder for snapshot content, used for integrity verification

// metadata contains placeholder, snapshot stored separately
console.log(result.metadata.length); // small
console.log(result.snapshot.length); // large

// Create instance with separated data (auto-validates hash)
const tv2 = new TextVersion(result.metadata, result.snapshot);
console.log(tv2.latest()); // "Very very very long latest version content..."

// Error will be thrown if snapshot hash doesn't match (prevents data tampering)
try {
  new TextVersion(result.metadata, 'wrong snapshot content');
} catch (e) {
  console.error('Hash validation failed'); // Snapshot content doesn't match hash in metadata
}

<!-- Include diff-match-patch dependency first -->
<script src="https://cdnjs.cloudflare.com/ajax/libs/diff_match_patch/20121119/diff_match_patch.js"></script>

<!-- Then include text-version UMD version -->
<script src="https://cdn.jsdelivr.net/npm/text-version/dist/index.umd.js"></script>

<!-- Or using unpkg CDN -->
<script src="https://cdnjs.cloudflare.com/ajax/libs/diff_match_patch/20121119/diff_match_patch.js"></script>
<script src="https://unpkg.com/text-version/dist/index.umd.js"></script>

<!DOCTYPE html>
<html>
<head>
    <title>Text-Version CDN Example</title>
</head>
<body>
    <h1>Text-Version Demo</h1>
    <textarea id="input" placeholder="Enter text content..." rows="5" cols="50">Hello, World!</textarea><br><br>
    <button onclick="commitVersion()">Commit Version</button>
    <button onclick="showLatest()">Show Latest</button>
    <button onclick="showLog()">Show Log</button><br><br>
    
    <div>
        <h3>Output:</h3>
        <pre id="output"></pre>
    </div>

    <!-- Include diff-match-patch dependency first -->
    <script src="https://cdnjs.cloudflare.com/ajax/libs/diff_match_patch/20121119/diff_match_patch.js"></script>
    <!-- Then include text-version -->
    <script src="https://cdn.jsdelivr.net/npm/text-version/dist/index.umd.js"></script>
    <script>
        // TextVersion available through global variable window.TextVersion
        const tv = new window.TextVersion.TextVersion();
        let versionCounter = 1;

        function commitVersion() {
            const text = document.getElementById('input').value;
            const version = `v${versionCounter++}`;
            tv.commit(text, version);
            
            document.getElementById('output').textContent = 
                `Version ${version} committed\nCurrent storage: ${tv.export()}`;
        }

        function showLatest() {
            const latest = tv.latest();
            document.getElementById('output').textContent = 
                `Latest version content:\n${latest}`;
        }

        function showLog() {
            const log = tv.log();
            const logText = log.map(info => 
                `${info.version} (${info.isSnapshot ? 'snapshot' : 'diff'})`
            ).join('\n');
            
            document.getElementById('output').textContent = 
                `Version history:\n${logText}`;
        }
    </script>
</body>
</html>

new TextVersion(initialStorage?: string, compressionProvider?: CompressionProvider)
new TextVersion(metadata: string, snapshot: string, compressionProvider?: CompressionProvider)

interface VersionInfo {
  version: string;      // Version name
  isSnapshot: boolean;  // Whether it's a snapshot version
}

interface CompressionProvider {
  compress(data: string): string;
  decompress(data: string): string;
}

interface DiffOperation {
  type: 'retain' | 'insert' | 'delete';
  length?: number;  // Number of characters for retain and delete operations
  text?: string;    // Text content for insert operations
}