import { describe, test, expect, beforeEach, afterEach } from 'vitest';
import { execSync } from 'child_process';

/**
 * Electron Build Smoke Test
 * 
 * Purpose: Detect browser context errors during Electron build
 * 
 * This test catches bundling issues where Node.js modules are imported
 * in the renderer process, causing runtime errors.
 * 
 * RED Phase: This test MUST FAIL due to externalized modules
 */

describe('Electron Build Smoke Tests', () => {
  test('should build Electron app without browser context errors', () => {
    // When: Building the Electron companion app
    let buildOutput: string;
    
    try {
      buildOutput = execSync('npm run companion:build', {
        cwd: process.cwd(),
        encoding: 'utf-8',
        stdio: 'pipe',
      });
    } catch (error: any) {
      buildOutput = error.stdout + error.stderr;
    }

    // Then: Build should not contain externalized module warnings
    const foundErrors: string[] = [];
    
    // Split output into lines and check each line
    const lines = buildOutput.split('\n');
    lines.forEach((line: string) => {
      if (line.includes('has been externalized for browser compatibility')) {
        foundErrors.push(line.trim());
      }
      if (line.includes('Cannot access') && line.includes('in client code')) {
        foundErrors.push(line.trim());
      }
    });

    // This WILL FAIL in RED phase due to electron/fs/path being externalized
    expect(
      foundErrors.length,
      `Browser context errors detected during build:\n\n${foundErrors.map((e, i) => `${i + 1}. ${e}`).join('\n')}\n\n` +
      `These indicate Node.js modules (electron, fs, path) are being imported in renderer code.\n` +
      `This will cause runtime errors when the app launches.`
    ).toBe(0);
  });

  test('should not import Node.js modules in renderer source code', () => {
    // Given: Renderer source code
    const fs = require('fs');
    const path = require('path');
    
    const rendererPath = path.join(
      process.cwd(),
      'apps/companion/renderer'
    );

    // When: Checking renderer source for forbidden imports
    const forbiddenPatterns = [
      { pattern: /from\s+['"]electron['"]/, name: 'electron' },
      { pattern: /require\(['"]electron['"]\)/, name: 'electron' },
      { pattern: /from\s+['"]fs['"]/, name: 'fs' },
      { pattern: /require\(['"]fs['"]\)/, name: 'fs' },
      { pattern: /from\s+['"]path['"]/, name: 'path' },
      { pattern: /require\(['"]path['"]\)/, name: 'path' },
    ];

    const violations: Array<{ file: string; line: number; import: string; module: string }> = [];

    function scanDirectory(dir: string) {
      const entries = fs.readdirSync(dir, { withFileTypes: true });
      
      entries.forEach((entry: any) => {
        const fullPath = path.join(dir, entry.name);
        
        if (entry.isDirectory()) {
          scanDirectory(fullPath);
        } else if (entry.name.endsWith('.tsx') || entry.name.endsWith('.ts')) {
          const content = fs.readFileSync(fullPath, 'utf-8');
          const lines = content.split('\n');
          
          lines.forEach((line: string, index: number) => {
            forbiddenPatterns.forEach(({ pattern, name }) => {
              if (pattern.test(line)) {
                violations.push({
                  file: path.relative(process.cwd(), fullPath),
                  line: index + 1,
                  import: line.trim(),
                  module: name,
                });
              }
            });
          });
        }
      });
    }

    scanDirectory(rendererPath);

    // Then: No Node.js modules should be imported in renderer
    expect(
      violations.length,
      `Found Node.js module imports in renderer source code:\n\n${
        violations.map(v => `${v.file}:${v.line}\n  Module: ${v.module}\n  Code: ${v.import}`).join('\n\n')
      }\n\nRenderer code must use the preload script or IPC to access Node.js APIs.`
    ).toBe(0);
  });
});