#!/usr/bin/env bun
/**
 * Extract TRACES from source code and generate requirement mapping
 *
 * Usage:
 *   bun run scripts/extract-traces.ts
 *   bun run scripts/extract-traces.ts --format json
 *   bun run scripts/extract-traces.ts --format markdown > docs/TRACEABILITY.md
 */

import * as fs from "fs";
import * as path from "path";

// Use built-in Bun.glob
const glob = (pattern: string) => new Bun.Glob(pattern);

interface TraceEntry {
  file: string;
  line: number;
  context: string;
  requirements: string[];
}

interface RequirementMapping {
  [reqId: string]: TraceEntry[];
}

interface TracesData {
  timestamp: string;
  totalFiles: number;
  totalTraces: number;
  requirements: RequirementMapping;
  byType: {
    UR: string[];
    IR: string[];
    DR: string[];
    JA: string[];
  };
}

const TRACES_PATTERN = /TRACES:\s*([^\n]+)/gi;
const REQ_ID_PATTERN = /([A-Z]{2})-(\d{3})/g;

function extractRequirementIds(tracesString: string): string[] {
  const matches = [...tracesString.matchAll(REQ_ID_PATTERN)];
  return matches.map((m) => `${m[1]}-${m[2]}`);
}

function getContext(content: string, lineNum: number): string {
  const lines = content.split("\n");
  const contextStart = Math.max(0, lineNum - 3);
  const contextEnd = Math.min(lines.length, lineNum + 1);
  const contextLines = lines.slice(contextStart, contextEnd);
  return contextLines.join("\n").trim();
}

async function extractTraces(): Promise<TracesData> {
  const patterns = [
    "src/**/*.ts",
    "src/**/*.svelte",
    "src-tauri/src/**/*.rs",
  ];

  const requirementMap: RequirementMapping = {};
  const byType: Record<string, Set<string>> = {
    UR: new Set(),
    IR: new Set(),
    DR: new Set(),
    JA: new Set(),
  };

  let totalTraces = 0;
  const processedFiles = new Set<string>();

  for (const pattern of patterns) {
    const globber = glob(pattern);
    const files = [];
    for await (const file of globber.scan({
      cwd: "/home/dtourolle/Development/JellyTau",
    })) {
      files.push(file);
    }

    for (const file of files) {
      if (processedFiles.has(file)) continue;
      processedFiles.add(file);

      try {
        const fullPath = `/home/dtourolle/Development/JellyTau/${file}`;
        const content = fs.readFileSync(fullPath, "utf-8");
        const lines = content.split("\n");

        let match;
        TRACES_PATTERN.lastIndex = 0;

        while ((match = TRACES_PATTERN.exec(content)) !== null) {
          const tracesStr = match[1];
          const reqIds = extractRequirementIds(tracesStr);

          if (reqIds.length === 0) continue;

          // Find line number
          const beforeMatch = content.substring(0, match.index);
          const lineNum = beforeMatch.split("\n").length - 1;

          // Get context (function/class name if available)
          let context = "Unknown";
          for (let i = lineNum; i >= Math.max(0, lineNum - 10); i--) {
            const line = lines[i];
            if (
              line.includes("function ") ||
              line.includes("export const ") ||
              line.includes("pub fn ") ||
              line.includes("pub enum ") ||
              line.includes("pub struct ") ||
              line.includes("impl ") ||
              line.includes("async function ") ||
              line.includes("class ")
            ) {
              context = line.trim();
              break;
            }
          }

          const entry: TraceEntry = {
            file: file.replace(/^\//, ""),
            line: lineNum + 1,
            context,
            requirements: reqIds,
          };

          for (const reqId of reqIds) {
            if (!requirementMap[reqId]) {
              requirementMap[reqId] = [];
            }
            requirementMap[reqId].push(entry);

            // Track by type
            const type = reqId.substring(0, 2);
            if (byType[type]) {
              byType[type].add(reqId);
            }
          }

          totalTraces++;
        }
      } catch (error) {
        console.error(`Error processing ${file}:`, error);
      }
    }
  }

  return {
    timestamp: new Date().toISOString(),
    totalFiles: processedFiles.size,
    totalTraces,
    requirements: requirementMap,
    byType: {
      UR: Array.from(byType["UR"]).sort(),
      IR: Array.from(byType["IR"]).sort(),
      DR: Array.from(byType["DR"]).sort(),
      JA: Array.from(byType["JA"]).sort(),
    },
  };
}

function generateMarkdown(data: TracesData): string {
  let md = `# Code Traceability Matrix

**Generated:** ${new Date(data.timestamp).toLocaleString()}

## Summary

- **Total Files Scanned:** ${data.totalFiles}
- **Total TRACES Found:** ${data.totalTraces}
- **Requirements Covered:**
  - User Requirements (UR): ${data.byType.UR.length}
  - Integration Requirements (IR): ${data.byType.IR.length}
  - Development Requirements (DR): ${data.byType.DR.length}
  - Jellyfin API Requirements (JA): ${data.byType.JA.length}

## Requirements by Type

### User Requirements (UR)
\`\`\`
${data.byType.UR.join(", ")}
\`\`\`

### Integration Requirements (IR)
\`\`\`
${data.byType.IR.join(", ")}
\`\`\`

### Development Requirements (DR)
\`\`\`
${data.byType.DR.join(", ")}
\`\`\`

### Jellyfin API Requirements (JA)
\`\`\`
${data.byType.JA.join(", ")}
\`\`\`

## Detailed Mapping

`;

  // Sort requirements by ID
  const sortedReqs = Object.keys(data.requirements).sort((a, b) => {
    const typeA = a.substring(0, 2);
    const typeB = b.substring(0, 2);
    const typeOrder = { UR: 0, IR: 1, DR: 2, JA: 3 };
    if (typeOrder[typeA] !== typeOrder[typeB]) {
      return (typeOrder[typeA] || 4) - (typeOrder[typeB] || 4);
    }
    return a.localeCompare(b);
  });

  for (const reqId of sortedReqs) {
    const entries = data.requirements[reqId];
    md += `### ${reqId}\n\n`;
    md += `**Locations:** ${entries.length} file(s)\n\n`;

    for (const entry of entries) {
      md += `- **File:** [\`${entry.file}\`](${entry.file}#L${entry.line})\n`;
      md += `  - **Line:** ${entry.line}\n`;
      md += `  - **Context:** \`${entry.context.substring(0, 80)}...\`\n`;
    }
    md += "\n";
  }

  return md;
}

function generateJson(data: TracesData): string {
  return JSON.stringify(data, null, 2);
}

// Main
const args = Bun.argv.slice(2);
const format = args.includes("--format")
  ? args[args.indexOf("--format") + 1]
  : "markdown";

console.error("Extracting TRACES from codebase...");
const data = await extractTraces();

if (format === "json") {
  console.log(generateJson(data));
} else {
  console.log(generateMarkdown(data));
}

console.error(`\n✅ Complete! Found ${data.totalTraces} TRACES across ${data.totalFiles} files`);