/**
 * Diagnostic formatting and reporting utilities.
 */

function formatSbomOverview({
  headImage,
  targetImage,
  headFiles = [],
  targetFiles = [],
  headError = null,
  targetError = null,
}) {
  const lines = [
    '',
    '================================================================================',
    '                      SBOM EXTRACTION DIAGNOSTIC OVERVIEW                       ',
    '================================================================================',
  ];

  if (headError) {
    lines.push(`HEAD Image (${headImage}): ❌ FAILED - ${headError}`);
  } else {
    lines.push(`HEAD Image (${headImage}): ✅ SUCCESS`);
    for (const f of headFiles) {
      lines.push(`  - ${f.name} (${f.size} bytes)`);
    }
  }

  if (targetError) {
    lines.push(`TARGET Baseline Image (${targetImage}): ❌ FAILED - ${targetError}`);
  } else {
    lines.push(`TARGET Baseline Image (${targetImage}): ✅ SUCCESS`);
    for (const f of targetFiles) {
      lines.push(`  - ${f.name} (${f.size} bytes)`);
    }
  }

  lines.push('================================================================================');
  lines.push('');
  return lines.join('\n');
}

function formatScanOverview({
  headImage,
  targetImage,
  targetBranch = 'main',
  strategy = null,
  headSummary = [],
  targetSummary = [],
}) {
  const lines = [
    '',
    '================================================================================',
    '                   CVE VULNERABILITY SCAN DIAGNOSTIC OVERVIEW                  ',
    '================================================================================',
  ];

  if (strategy) {
    lines.push(`Scan Strategy: ${strategy}`);
    lines.push('--------------------------------------------------------------------------------');
  }

  lines.push(`HEAD Image: ${headImage}`);
  for (const line of headSummary) {
    lines.push(line);
  }

  lines.push('');
  lines.push(`TARGET Baseline Image: ${targetImage} (branch: '${targetBranch}')`);
  for (const line of targetSummary) {
    lines.push(line);
  }

  lines.push('================================================================================');
  lines.push('');
  return lines.join('\n');
}

function countVulnerabilities(report) {
  if (!report) return 0;
  let data = report;
  if (typeof report === 'string' || Buffer.isBuffer(report)) {
    try {
      data = JSON.parse(report.toString('utf8'));
    } catch {
      return 0;
    }
  }
  if (!data || typeof data !== 'object') return 0;

  let count = 0;
  if (Array.isArray(data.Results)) {
    for (const res of data.Results) {
      if (res && Array.isArray(res.Vulnerabilities)) {
        count += res.Vulnerabilities.length;
      }
    }
  }
  return count;
}

module.exports = {
  formatSbomOverview,
  formatScanOverview,
  countVulnerabilities,
};