name: Revalidate PR

on:
  workflow_dispatch:
    inputs:
      pr_number:
        description: 'PR number to validate'
        required: true
        type: string

permissions:
  contents: read
  pull-requests: write
  issues: write
  checks: write
  statuses: write

jobs:
  revalidate:
    runs-on: ubuntu-latest
    steps:
      - name: Get PR data
        id: pr_data
        uses: actions/github-script@v9
        with:
          script: |
            const { data: pr } = await github.rest.pulls.get({
              owner: context.repo.owner,
              repo: context.repo.repo,
              pull_number: ${{ inputs.pr_number }}
            });

            core.info(`Validating PR #${pr.number}: ${pr.title}`);
            core.info(`Author: ${pr.user.login}`);
            core.info(`Changes: +${pr.additions} -${pr.deletions}`);

            // Store head SHA for creating status
            core.setOutput('head_sha', pr.head.sha);

            return pr;

      - name: Create pending status
        uses: actions/github-script@v9
        with:
          script: |
            await github.rest.repos.createCommitStatus({
              owner: context.repo.owner,
              repo: context.repo.repo,
              sha: '${{ steps.pr_data.outputs.head_sha }}',
              state: 'pending',
              context: 'Manual Validation',
              description: 'Running validation checks...'
            });

      - name: Validate PR
        id: validate
        uses: actions/github-script@v9
        with:
          script: |
            const pr = ${{ steps.pr_data.outputs.result }};
            const errors = [];
            let passed = true;

            // Check size
            const totalChanges = pr.additions + pr.deletions;
            const MAX_LINES = 1000;
            if (totalChanges > MAX_LINES) {
              errors.push(`PR size (${totalChanges} lines) exceeds ${MAX_LINES} line limit`);
              passed = false;
            }

            // Check template
            const body = pr.body || '';
            const requiredSections = ["# Description", "Fixes #", "# How Has This Been Tested?", "# Checklist"];
            const missingSections = requiredSections.filter(section => !body.includes(section));

            if (missingSections.length > 0) {
              errors.push(`Missing PR template sections: ${missingSections.join(', ')}`);
              passed = false;
            }

            if (body.match(/Replace this with|Choose one:|Fixes #\[issue number\]/i)) {
              errors.push('PR template contains unmodified placeholders');
              passed = false;
            }

            // Check linked issue
            const issueMatch = body.match(/(?:Fixes|Closes|Resolves)\s+#(\d+)/i);
            if (!issueMatch) {
              errors.push('No linked issue found');
              passed = false;
            }

            // Store results
            core.setOutput('passed', passed);
            core.setOutput('errors', errors.join('; '));
            core.setOutput('totalChanges', totalChanges);
            core.setOutput('hasTemplate', missingSections.length === 0);
            core.setOutput('hasIssue', !!issueMatch);

            if (!passed) {
              core.setFailed(errors.join('; '));
            }

      - name: Update commit status
        if: always()
        uses: actions/github-script@v9
        with:
          script: |
            const passed = ${{ steps.validate.outputs.passed }};
            const errors = '${{ steps.validate.outputs.errors }}';

            await github.rest.repos.createCommitStatus({
              owner: context.repo.owner,
              repo: context.repo.repo,
              sha: '${{ steps.pr_data.outputs.head_sha }}',
              state: passed ? 'success' : 'failure',
              context: 'Manual Validation',
              description: passed ? 'All validation checks passed' : errors.substring(0, 140),
              target_url: `https://github.com/${context.repo.owner}/${context.repo.repo}/actions/runs/${context.runId}`
            });

      - name: Add validation comment
        if: always()
        uses: actions/github-script@v9
        with:
          script: |
            const pr = ${{ steps.pr_data.outputs.result }};
            const passed = ${{ steps.validate.outputs.passed }};
            const totalChanges = ${{ steps.validate.outputs.totalChanges }};
            const hasTemplate = ${{ steps.validate.outputs.hasTemplate }};
            const hasIssue = ${{ steps.validate.outputs.hasIssue }};
            const errors = '${{ steps.validate.outputs.errors }}'.split('; ').filter(e => e);

            let body = `### Manual Validation Results\n\n`;
            body += `**Status**: ${passed ? '✅ Passed' : '❌ Failed'}\n\n`;
            body += `| Check | Status | Details |\n`;
            body += `|-------|--------|----------|\n`;
            body += `| PR Size | ${totalChanges <= 1000 ? '✅' : '❌'} | ${totalChanges} lines ${totalChanges > 1000 ? '(exceeds 1000 limit)' : ''} |\n`;
            body += `| Template | ${hasTemplate ? '✅' : '❌'} | ${hasTemplate ? 'Complete' : 'Missing required sections'} |\n`;
            body += `| Linked Issue | ${hasIssue ? '✅' : '❌'} | ${hasIssue ? 'Found' : 'Missing Fixes/Closes #XXX'} |\n`;

            if (errors.length > 0) {
              body += `\n**Errors:**\n`;
              errors.forEach(error => {
                body += `- ❌ ${error}\n`;
              });
            }

            body += `\n[View workflow run](https://github.com/${context.repo.owner}/${context.repo.repo}/actions/runs/${context.runId})`;

            await github.rest.issues.createComment({
              owner: context.repo.owner,
              repo: context.repo.repo,
              issue_number: pr.number,
              body: body
            });