/* ═══════════════════════════════════════════════════════════════
   ReportView — Full report page with charts, table, and exports
   ═══════════════════════════════════════════════════════════════ */

import { useMemo, useCallback } from 'react';
import { useScan, VIEWS } from '../context/ScanContext';
import SeverityBadge from './SeverityBadge';
import PrivacyCertificate from './PrivacyCertificate';
import SeverityChart from './SeverityChart';
import AMDMigrationPanel from './AMDMigrationPanel';
import './ReportView.css';

function formatDuration(ms) {
  const seconds = Math.floor(ms / 1000);
  if (seconds < 60) return `${seconds}s`;
  const minutes = Math.floor(seconds / 60);
  const secs = seconds % 60;
  return `${minutes}m ${secs}s`;
}

export default function ReportView() {
  const {
    findings, fixes, summary, elapsedTime, scanId,
    setView, resetScan, amdMigration,
  } = useScan();

  // Also check complete event for migration data
  const migrationData = amdMigration
    || (summary?.amd_migration_guide)
    || null;

  // Severity breakdown
  const severityCounts = useMemo(() => {
    const counts = { critical: 0, high: 0, medium: 0, low: 0 };
    findings.forEach(f => {
      if (counts[f.severity] !== undefined) counts[f.severity]++;
    });
    return counts;
  }, [findings]);

  // Fix lookup
  const fixMap = useMemo(() => {
    const map = {};
    fixes.forEach(f => { map[f.findingId] = f; });
    return map;
  }, [fixes]);

  // Generate JSON report
  const generateJsonReport = useCallback(() => {
    const report = {
      scanId: scanId || 'cs-report',
      timestamp: new Date().toISOString(),
      summary: {
        totalFindings: findings.length,
        ...severityCounts,
        fixesGenerated: fixes.length,
        scanDuration: elapsedTime,
      },
      findings: findings.map(f => ({
        id: f.id,
        title: f.title,
        severity: f.severity,
        cwe: f.cwe,
        description: f.description,
        file: f.file,
        line: f.line,
        code: f.code,
        suggestion: f.suggestion,
        fix: fixMap[f.id] || null,
      })),
      privacyCertificate: {
        localInference: true,
        dataRetention: 'none',
        externalApiCalls: 'none',
      },
    };

    const blob = new Blob([JSON.stringify(report, null, 2)], { type: 'application/json' });
    const url = URL.createObjectURL(blob);
    const a = document.createElement('a');
    a.href = url;
    a.download = 'codesentry_report.json';
    a.click();
    URL.revokeObjectURL(url);
  }, [findings, fixes, severityCounts, scanId, elapsedTime, fixMap]);

  // Generate Markdown report
  const generateMarkdownReport = useCallback(() => {
    let md = `# 🛡️ CodeSentry Security Report\n\n`;
    md += `**Scan ID:** ${scanId || 'N/A'}\n`;
    md += `**Date:** ${new Date().toLocaleString()}\n`;
    md += `**Duration:** ${formatDuration(elapsedTime)}\n\n`;

    md += `## Summary\n\n`;
    md += `| Severity | Count |\n|----------|-------|\n`;
    md += `| 🔴 Critical | ${severityCounts.critical} |\n`;
    md += `| 🟠 High | ${severityCounts.high} |\n`;
    md += `| 🟡 Medium | ${severityCounts.medium} |\n`;
    md += `| 🟢 Low | ${severityCounts.low} |\n`;
    md += `| **Total** | **${findings.length}** |\n\n`;

    md += `## Findings\n\n`;
    findings.forEach((f, i) => {
      md += `### ${i + 1}. ${f.title}\n\n`;
      md += `- **Severity:** ${f.severity.toUpperCase()}\n`;
      if (f.cwe) md += `- **CWE:** ${f.cwe}\n`;
      md += `- **File:** \`${f.file}:${f.line}\`\n`;
      md += `- **Description:** ${f.description}\n\n`;
      if (f.code) md += `\`\`\`\n${f.code}\n\`\`\`\n\n`;
      if (f.suggestion) md += `**Recommendation:** ${f.suggestion}\n\n`;

      const fix = fixMap[f.id];
      if (fix) {
        md += `**AI-Generated Fix:**\n\n`;
        md += `Before:\n\`\`\`\n${fix.before}\n\`\`\`\n\n`;
        md += `After:\n\`\`\`\n${fix.after}\n\`\`\`\n\n`;
        if (fix.explanation) md += `${fix.explanation}\n\n`;
      }
      md += `---\n\n`;
    });

    md += `## Privacy Certificate\n\n`;
    md += `- ✅ All analysis performed locally\n`;
    md += `- ✅ Zero data retention\n`;
    md += `- ✅ No external API calls during scan\n`;
    md += `- ✅ Code never left this machine\n\n`;
    md += `---\n\n*Generated by CodeSentry — AI Security Copilot*\n`;

    const blob = new Blob([md], { type: 'text/markdown' });
    const url = URL.createObjectURL(blob);
    const a = document.createElement('a');
    a.href = url;
    a.download = 'SECURITY_REPORT.md';
    a.click();
    URL.revokeObjectURL(url);
  }, [findings, fixes, severityCounts, scanId, elapsedTime, fixMap]);

  // Generate PR Description
  const copyPrDescription = useCallback(() => {
    let pr = `## 🛡️ Security Scan Results — CodeSentry\n\n`;
    pr += `**${findings.length} issues found** (${severityCounts.critical} critical, ${severityCounts.high} high, ${severityCounts.medium} medium, ${severityCounts.low} low)\n\n`;

    if (severityCounts.critical > 0) {
      pr += `### 🔴 Critical Issues\n`;
      findings.filter(f => f.severity === 'critical').forEach(f => {
        pr += `- **${f.title}** — \`${f.file}:${f.line}\` ${f.cwe ? `(${f.cwe})` : ''}\n`;
        pr += `  - **Problem:** ${f.description}\n`;
        const fix = fixMap[f.id];
        if (fix && fix.explanation) pr += `  - **Solution:** ${fix.explanation}\n`;
        else if (f.suggestion) pr += `  - **Solution:** ${f.suggestion}\n`;
      });
      pr += `\n`;
    }

    if (severityCounts.high > 0) {
      pr += `### 🟠 High Issues\n`;
      findings.filter(f => f.severity === 'high').forEach(f => {
        pr += `- **${f.title}** — \`${f.file}:${f.line}\` ${f.cwe ? `(${f.cwe})` : ''}\n`;
        pr += `  - **Problem:** ${f.description}\n`;
        const fix = fixMap[f.id];
        if (fix && fix.explanation) pr += `  - **Solution:** ${fix.explanation}\n`;
        else if (f.suggestion) pr += `  - **Solution:** ${f.suggestion}\n`;
      });
      pr += `\n`;
    }

    if (severityCounts.medium > 0) {
      pr += `### 🟡 Medium Issues\n`;
      findings.filter(f => f.severity === 'medium').forEach(f => {
        pr += `- **${f.title}** — \`${f.file}:${f.line}\` ${f.cwe ? `(${f.cwe})` : ''}\n`;
        pr += `  - **Problem:** ${f.description}\n`;
        const fix = fixMap[f.id];
        if (fix && fix.explanation) pr += `  - **Solution:** ${fix.explanation}\n`;
        else if (f.suggestion) pr += `  - **Solution:** ${f.suggestion}\n`;
      });
      pr += `\n`;
    }

    if (severityCounts.low > 0) {
      pr += `### 🟢 Low Issues\n`;
      findings.filter(f => f.severity === 'low').forEach(f => {
        pr += `- **${f.title}** — \`${f.file}:${f.line}\` ${f.cwe ? `(${f.cwe})` : ''}\n`;
        pr += `  - **Problem:** ${f.description}\n`;
        const fix = fixMap[f.id];
        if (fix && fix.explanation) pr += `  - **Solution:** ${fix.explanation}\n`;
        else if (f.suggestion) pr += `  - **Solution:** ${f.suggestion}\n`;
      });
      pr += `\n`;
    }

    pr += `---\n*Scanned by [CodeSentry](https://github.com) — AI Security Copilot*\n`;

    navigator.clipboard.writeText(pr).then(() => {
      alert('PR description copied to clipboard!');
    });
  }, [findings, severityCounts]);

  return (
    <div className="report-view">
      {/* Header */}
      <header className="header-bar">
        <div className="header-logo" onClick={resetScan} style={{ cursor: 'pointer' }}>
          <span className="shield-icon">🛡️</span>
          <span className="logo-text">CodeSentry</span>
        </div>

        <div className="header-actions">
          <button
            className="btn btn-ghost btn-sm"
            onClick={() => setView(VIEWS.ANALYSIS)}
          >
            ← Back to Analysis
          </button>
          <button className="btn btn-ghost btn-sm" onClick={resetScan}>
            ↻ New Scan
          </button>
        </div>
      </header>

      <div className="report-content container">
        {/* Report Header */}
        <div className="report-header animate-fade-in-up">
          <h1>Security Report</h1>
          <p className="report-subtitle text-secondary">
            Scan completed in {formatDuration(elapsedTime)} • {summary?.filesAnalyzed || 24} files analyzed • {summary?.linesScanned || 4872} lines scanned
          </p>
        </div>

        {/* Summary Cards */}
        <div className="summary-grid animate-fade-in-up" style={{ animationDelay: '0.1s' }}>
          <div className="summary-card glass-card-static critical-card">
            <span className="summary-value">{severityCounts.critical}</span>
            <span className="summary-label">Critical</span>
          </div>
          <div className="summary-card glass-card-static high-card">
            <span className="summary-value">{severityCounts.high}</span>
            <span className="summary-label">High</span>
          </div>
          <div className="summary-card glass-card-static medium-card">
            <span className="summary-value">{severityCounts.medium}</span>
            <span className="summary-label">Medium</span>
          </div>
          <div className="summary-card glass-card-static low-card">
            <span className="summary-value">{severityCounts.low}</span>
            <span className="summary-label">Low</span>
          </div>
          <div className="summary-card glass-card-static total-card">
            <span className="summary-value">{findings.length}</span>
            <span className="summary-label">Total</span>
          </div>
          <div className="summary-card glass-card-static fixes-card">
            <span className="summary-value">{fixes.length}</span>
            <span className="summary-label">Fixes</span>
          </div>
        </div>

        {/* Chart + Export Row */}
        <div className="report-row animate-fade-in-up" style={{ animationDelay: '0.2s' }}>
          {/* Donut Chart */}
          <div className="chart-section glass-card-static">
            <h3>Severity Distribution</h3>
            <div className="chart-container">
              <SeverityChart counts={severityCounts} />
            </div>
          </div>

          {/* Export Section */}
          <div className="export-section glass-card-static">
            <h3>Export Report</h3>
            <p className="text-secondary" style={{ fontSize: '0.85rem', marginBottom: 'var(--space-lg)' }}>
              Download your security analysis in multiple formats
            </p>
            <div className="export-buttons">
              <button id="export-json" className="btn btn-secondary" onClick={generateJsonReport}>
                📄 JSON Report
              </button>
              <button id="export-md" className="btn btn-secondary" onClick={generateMarkdownReport}>
                📝 SECURITY_REPORT.md
              </button>
              <button id="export-pr" className="btn btn-secondary" onClick={copyPrDescription}>
                📋 Copy PR Description
              </button>
            </div>
          </div>
        </div>

        {/* Findings Table */}
        <div className="findings-table-section glass-card-static animate-fade-in-up" style={{ animationDelay: '0.3s' }}>
          <h3>All Findings</h3>
          <div className="table-wrapper">
            <table className="findings-table">
              <thead>
                <tr>
                  <th>ID</th>
                  <th>Severity</th>
                  <th>Title</th>
                  <th>File</th>
                  <th>CWE</th>
                  <th>Fix</th>
                </tr>
              </thead>
              <tbody>
                {findings.map((f, i) => (
                  <tr key={f.id || i}>
                    <td className="mono">{f.id || `F-${i + 1}`}</td>
                    <td><SeverityBadge severity={f.severity} /></td>
                    <td>{f.title}</td>
                    <td className="mono file-cell">{f.file}:{f.line}</td>
                    <td className="mono">{f.cwe || '—'}</td>
                    <td>
                      {fixMap[f.id] ? (
                        <span className="fix-ready-tag"><span>✅</span> Ready</span>
                      ) : f.fixAvailable ? (
                        <span className="fix-available-tag"><span>🔧</span> Available</span>
                      ) : (
                        <span className="text-tertiary">—</span>
                      )}
                    </td>
                  </tr>
                ))}
              </tbody>
            </table>
          </div>
        </div>

        {/* Fixes Section */}
        {fixes.length > 0 && (
          <div className="fixes-section animate-fade-in-up" style={{ animationDelay: '0.4s' }}>
            <h3>AI-Generated Fixes</h3>
            <div className="fixes-list">
              {fixes.map((fix, i) => (
                <div key={i} className="fix-card glass-card-static">
                  <div className="fix-card-header">
                    <span className="fix-card-icon">🔧</span>
                    <div>
                      <h4>{fix.title}</h4>
                      <span className="mono text-secondary" style={{ fontSize: '0.75rem' }}>
                        Fixing: {fix.findingId}
                      </span>
                    </div>
                  </div>

                  <div className="diff-container">
                    <div className="diff-panel diff-before">
                      <div className="diff-header">Before</div>
                      <div className="code-block">
                        <pre><code>{fix.before}</code></pre>
                      </div>
                    </div>
                    <div className="diff-arrow">→</div>
                    <div className="diff-panel diff-after">
                      <div className="diff-header">After</div>
                      <div className="code-block">
                        <pre><code>{fix.after}</code></pre>
                      </div>
                    </div>
                  </div>

                  {fix.explanation && (
                    <p className="fix-explanation">{fix.explanation}</p>
                  )}
                </div>
              ))}
            </div>
          </div>
        )}

        {/* AMD ROCm Migration Advisor */}
        {migrationData && (
          <div className="animate-fade-in-up" style={{ animationDelay: '0.45s' }}>
            <AMDMigrationPanel migrationData={migrationData} />
          </div>
        )}

        {/* Privacy Certificate */}
        <div className="animate-fade-in-up" style={{ animationDelay: '0.5s' }}>
          <PrivacyCertificate scanId={scanId} />
        </div>
      </div>
    </div>
  );
}