/**
 * Test suite for markdown_to_html WASM module
 */
const fs = require('fs');
// TODO: Fix the rules so that it can do relative import.
const wasm = fs.readFileSync('markdown_converter/wasm/markdown_to_html_wasm.wasm');

let testsPassed = 0;
let testsFailed = 0;

function assertEqual(actual, expected, testName) {
  if (actual === expected) {
    console.log(`✓ ${testName}`);
    testsPassed++;
  } else {
    console.log(`✗ ${testName}`);
    console.log(`  Expected: ${expected}`);
    console.log(`  Actual:   ${actual}`);
    testsFailed++;
  }
}

function assertContains(actual, expected, testName) {
  if (actual.includes(expected)) {
    console.log(`✓ ${testName}`);
    testsPassed++;
  } else {
    console.log(`✗ ${testName}`);
    console.log(`  Expected to contain: ${expected}`);
    console.log(`  Actual: ${actual}`);
    testsFailed++;
  }
}

async function runTests() {
  const module = await WebAssembly.instantiate(wasm, { env: {} });
  const { malloc, heap_reset, markdown_to_html, memory } = module.instance.exports;

  function writeString(str) {
    const encoder = new TextEncoder();
    const bytes = encoder.encode(str + '\0');
    const ptr = malloc(bytes.length);
    new Uint8Array(memory.buffer).set(bytes, ptr);
    return ptr;
  }

  function readString(ptr) {
    const mem = new Uint8Array(memory.buffer);
    let end = ptr;
    while (mem[end] !== 0) end++;
    return new TextDecoder().decode(mem.slice(ptr, end));
  }

  function convert(md) {
    heap_reset();
    const inputPtr = writeString(md);
    const outputPtr = markdown_to_html(inputPtr);
    return readString(outputPtr);
  }

  console.log('Running markdown_to_html WASM tests...\n');

  // Test: Headings
  console.log('--- Headings ---');
  assertEqual(convert('# Hello'), '<h1>Hello</h1>', 'H1 heading');
  assertEqual(convert('## World'), '<h2>World</h2>', 'H2 heading');
  assertEqual(convert('### Level 3'), '<h3>Level 3</h3>', 'H3 heading');
  assertEqual(convert('###### Level 6'), '<h6>Level 6</h6>', 'H6 heading');

  // Test: Inline formatting
  console.log('\n--- Inline Formatting ---');
  assertEqual(convert('**bold**'), '<p><strong>bold</strong></p>', 'Bold with **');
  assertEqual(convert('__bold__'), '<p><strong>bold</strong></p>', 'Bold with __');
  assertEqual(convert('*italic*'), '<p><em>italic</em></p>', 'Italic with *');
  assertEqual(convert('_italic_'), '<p><em>italic</em></p>', 'Italic with _');
  assertEqual(convert('~~strike~~'), '<p><del>strike</del></p>', 'Strikethrough');
  assertEqual(convert('`code`'), '<p><code>code</code></p>', 'Inline code');

  // Test: Links and Images
  console.log('\n--- Links and Images ---');
  assertEqual(convert('[link](http://example.com)'), '<p><a href="http://example.com">link</a></p>', 'Link');
  assertEqual(convert('![alt](http://img.png)'), '<p><img src="http://img.png" alt="alt"></p>', 'Image');

  // Test: Lists
  console.log('\n--- Lists ---');
  assertEqual(convert('- item1\n- item2'), '<ul><li>item1</li><li>item2</li></ul>', 'Unordered list with -');
  assertEqual(convert('* item1\n* item2'), '<ul><li>item1</li><li>item2</li></ul>', 'Unordered list with *');
  assertEqual(convert('1. first\n2. second'), '<ol><li>first</li><li>second</li></ol>', 'Ordered list');

  // Test: Code block
  console.log('\n--- Code Block ---');
  const codeBlock = '```\nfunction test() {\n  return 42;\n}\n```';
  assertContains(convert(codeBlock), '<pre><code>', 'Code block opens');
  assertContains(convert(codeBlock), '</code></pre>', 'Code block closes');

  // Test: Blockquote
  console.log('\n--- Blockquote ---');
  assertEqual(convert('> quote'), '<blockquote>quote </blockquote>', 'Blockquote');

  // Test: Horizontal rule
  console.log('\n--- Horizontal Rule ---');
  assertEqual(convert('---'), '<hr>', 'HR with ---');
  assertEqual(convert('***'), '<hr>', 'HR with ***');
  assertEqual(convert('___'), '<hr>', 'HR with ___');

  // Test: Tables
  console.log('\n--- Tables ---');
  const table = '| Name | Age |\n|------|-----|\n| Alice | 30 |\n| Bob | 25 |';
  const tableHtml = convert(table);
  assertContains(tableHtml, '<table>', 'Table opens');
  assertContains(tableHtml, '</table>', 'Table closes');
  assertContains(tableHtml, '<thead>', 'Table has thead');
  assertContains(tableHtml, '<tbody>', 'Table has tbody');
  assertContains(tableHtml, '<th>Name</th>', 'Table header cell');
  assertContains(tableHtml, '<td>Alice</td>', 'Table body cell');

  // Test: Complex table with inline formatting
  console.log('\n--- Table with Inline Formatting ---');
  const complexTable = '| Feature | Status |\n|---------|--------|\n| **Bold** | *done* |';
  const complexTableHtml = convert(complexTable);
  assertContains(complexTableHtml, '<strong>Bold</strong>', 'Bold in table cell');
  assertContains(complexTableHtml, '<em>done</em>', 'Italic in table cell');

  // Test: HTML escaping
  console.log('\n--- HTML Escaping ---');
  assertContains(convert('<script>'), '&lt;script&gt;', 'Escapes < and >');
  assertContains(convert('a & b'), '&amp;', 'Escapes &');

  // Test: Mixed content
  console.log('\n--- Mixed Content ---');
  const mixed = '# Title\n\nSome **bold** text.\n\n- item 1\n- item 2';
  const mixedHtml = convert(mixed);
  assertContains(mixedHtml, '<h1>Title</h1>', 'Mixed: heading');
  assertContains(mixedHtml, '<strong>bold</strong>', 'Mixed: bold');
  assertContains(mixedHtml, '<ul>', 'Mixed: list');

  // Summary
  console.log('\n========================================');
  console.log(`Tests passed: ${testsPassed}`);
  console.log(`Tests failed: ${testsFailed}`);

  if (testsFailed > 0) {
    process.exit(1);
  }
}

runTests().catch(err => {
  console.error('Test error:', err);
  process.exit(1);
});