#!/usr/bin/env node

/**
 * Version Bumping Script
 * 
 * Bumps the version based on conventional commits since last release.
 * Supports:
 * - major: Breaking changes (! or BREAKING CHANGE)
 * - minor: Features (feat:)
 * - patch: Fixes (fix:) and other changes
 */

const { execSync } = require('child_process');
const fs = require('fs');
const path = require('path');

// Parse command line arguments
const args = process.argv.slice(2);
const forcedVersion = args[0]; // e.g., "0.2.0" or "patch/minor/major"

// Paths
const packageJsonPath = path.join(__dirname, '..', 'package.json');
const changelogPath = path.join(__dirname, '..', 'CHANGELOG.md');

// Load current version from package.json
function getCurrentVersion() {
  const packageJson = JSON.parse(fs.readFileSync(packageJsonPath, 'utf8'));
  return packageJson.version;
}

// Parse version string into components
function parseVersion(version) {
  const [major, minor, patch] = version.split('.').map(Number);
  return { major, minor, patch };
}

// Format version string
function formatVersion(major, minor, patch) {
  return `${major}.${minor}.${patch}`;
}

// Get commits since last tag
function getCommitsSinceLastTag() {
  try {
    const tags = execSync('git tag --sort=-version:refname', { encoding: 'utf8' }).trim();
    const latestTag = tags.split('\n')[0];

    if (!latestTag) {
      // No tags yet, get all commits
      return execSync('git log --oneline --format=%s', { encoding: 'utf8' }).trim().split('\n');
    }

    const commits = execSync(`git log ${latestTag}..HEAD --oneline --format=%s`, { encoding: 'utf8' }).trim();
    return commits ? commits.split('\n') : [];
  } catch (error) {
    // If no commits since tag or other error, get recent commits
    return execSync('git log --oneline --format=%s -n 20', { encoding: 'utf8' }).trim().split('\n');
  }
}

// Analyze commits to determine version bump type
function analyzeCommits(commits) {
  let bumpType = 'patch'; // default

  for (const commit of commits) {
    if (!commit) continue;

    // Breaking change indicators
    if (commit.includes('!') || commit.includes('BREAKING CHANGE')) {
      bumpType = 'major';
      break; // Major takes precedence
    }

    // Feature indicators
    if (commit.startsWith('feat:') || commit.startsWith('feat(')) {
      if (bumpType === 'patch') {
        bumpType = 'minor';
      }
    }

    // Fix indicators (already patch by default)
  }

  return bumpType;
}

// Generate new version based on bump type
function generateNewVersion(currentVersion, bumpType) {
  const { major, minor, patch } = parseVersion(currentVersion);

  switch (bumpType) {
    case 'major':
      return formatVersion(major + 1, 0, 0);
    case 'minor':
      return formatVersion(major, minor + 1, 0);
    case 'patch':
    default:
      return formatVersion(major, minor, patch + 1);
  }
}

// Update package.json version
function updatePackageJson(newVersion) {
  const packageJson = JSON.parse(fs.readFileSync(packageJsonPath, 'utf8'));
  packageJson.version = newVersion;
  fs.writeFileSync(packageJsonPath, JSON.stringify(packageJson, null, 2) + '\n');
  console.log(`✓ Updated package.json to version ${newVersion}`);
}

// Generate changelog entry
function generateChangelogEntry(newVersion, commits, bumpType) {
  const date = new Date().toISOString().split('T')[0];
  const relevantCommits = commits.filter(commit => {
    if (!commit) return false;
    // Filter out non-user-facing commits
    if (commit.startsWith('chore:') && !commit.includes('BREAKING')) return false;
    return true;
  });

  const changelogEntry = `## [${newVersion}] - ${date}\n\n` +
    `### ${bumpType.charAt(0).toUpperCase() + bumpType.slice(1)} Changes\n\n` +
    relevantCommits.map(commit => `- ${commit}`).join('\n') +
    '\n\n';

  return changelogEntry;
}

// Update CHANGELOG.md
function updateChangelog(newVersion, commits, bumpType) {
  const changelogEntry = generateChangelogEntry(newVersion, commits, bumpType);

  if (fs.existsSync(changelogPath)) {
    const content = fs.readFileSync(changelogPath, 'utf8');
    const newContent = changelogEntry + content;
    fs.writeFileSync(changelogPath, newContent);
  } else {
    fs.writeFileSync(changelogPath, `# Changelog\n\n${changelogEntry}`);
  }

  console.log(`✓ Updated CHANGELOG.md`);
}

// Main function
function main() {
  console.log('🔄 Version Bumping Tool\n');

  const currentVersion = getCurrentVersion();
  console.log(`Current version: ${currentVersion}`);

  let newVersion;
  let bumpType;

  if (forcedVersion) {
    // Check if it's a bump type or explicit version
    if (['patch', 'minor', 'major'].includes(forcedVersion.toLowerCase())) {
      bumpType = forcedVersion.toLowerCase();
      newVersion = generateNewVersion(currentVersion, bumpType);
      console.log(`Forced bump type: ${bumpType}`);
    } else {
      // Assume it's an explicit version
      newVersion = forcedVersion;
      bumpType = 'custom';
      console.log(`Forced version: ${newVersion}`);
    }
  } else {
    // Analyze commits to determine bump type
    const commits = getCommitsSinceLastTag();
    console.log(`\nAnalyzing ${commits.length} commits since last release...`);

    bumpType = analyzeCommits(commits);
    newVersion = generateNewVersion(currentVersion, bumpType);

    console.log(`\nDetected bump type: ${bumpType}`);
    console.log(`New version: ${currentVersion} → ${newVersion}`);
  }

  // Confirm with user
  const readline = require('readline');
  const rl = readline.createInterface({
    input: process.stdin,
    output: process.stdout
  });

  rl.question(`\nApply version ${newVersion}? (y/N) `, (answer) => {
    if (answer.toLowerCase() === 'y' || answer.toLowerCase() === 'yes') {
      // Update package.json
      updatePackageJson(newVersion);

      // Update changelog
      if (bumpType !== 'custom') {
        const commits = getCommitsSinceLastTag();
        updateChangelog(newVersion, commits, bumpType);
      }

      console.log(`\n✅ Version bumped to ${newVersion}`);
      console.log(`\nNext steps:`);
      console.log(`  1. Review changes: git diff`);
      console.log(`  2. Commit changes: git commit -am "chore: bump version to v${newVersion}"`);
      console.log(`  3. Create tag: git tag -a v${newVersion} -m "Release v${newVersion}"`);
      console.log(`  4. Push changes: git push origin main`);
      console.log(`  5. Push tag: git push origin v${newVersion}`);
    } else {
      console.log('❌ Version bump cancelled');
    }

    rl.close();
  });
}

// Run main function
main();