#!/usr/bin/env node
/**
 * ═══════════════════════════════════════════
 * NEXUS TEXTURE AUDIT CLI — Standalone Audit Tool
 * ═══════════════════════════════════════════
 * 
 * Command-line tool to audit textures in the Nexus project.
 * Provides compression recommendations and VRAM estimates.
 */

const fs = require('fs');
const path = require('path');
const { execSync } = require('child_process');

// Configuration
const CONFIG = {
  maxTextureSize: 2048,
  maxTotalTextures: 50,
  maxTotalVRAM: 256 * 1024 * 1024, // 256MB
  textureExtensions: ['.png', '.jpg', '.jpeg', '.gif', '.bmp', '.webp', '.basis', '.ktx2'],
  imageMagickPath: 'convert', // Path to ImageMagick convert
};

class TextureAuditor {
  constructor(projectRoot) {
    this.projectRoot = projectRoot;
    this.textureFiles = [];
    this.auditResults = [];
    this.totalVRAM = 0;
  }

  /**
   * Scan project for texture files
   */
  scanForTextures() {
    console.log(`Scanning ${this.projectRoot} for textures...`);
    
    const scanDir = (dir) => {
      const entries = fs.readdirSync(dir, { withFileTypes: true });
      
      for (const entry of entries) {
        const fullPath = path.join(dir, entry.name);
        
        if (entry.isDirectory()) {
          // Skip node_modules and .git
          if (entry.name !== 'node_modules' && entry.name !== '.git') {
            scanDir(fullPath);
          }
        } else if (entry.isFile()) {
          const ext = path.extname(entry.name).toLowerCase();
          if (CONFIG.textureExtensions.includes(ext)) {
            this.textureFiles.push(fullPath);
          }
        }
      }
    };
    
    scanDir(this.projectRoot);
    console.log(`Found ${this.textureFiles.length} texture files`);
    return this.textureFiles;
  }

  /**
   * Audit a single texture file
   */
  auditTexture(filePath) {
    const result = {
      file: path.relative(this.projectRoot, filePath),
      issues: [],
      recommendations: [],
      score: 100,
    };

    try {
      const stats = fs.statSync(filePath);
      const fileSize = stats.size;
      const ext = path.extname(filePath).toLowerCase();

      // Get image dimensions if possible
      let width = 0;
      let height = 0;
      
      try {
        const identify = execSync(`${CONFIG.imageMagickPath} -format "%wx%h" "${filePath}"`, { encoding: 'utf8' });
        const match = identify.match(/(\d+)x(\d+)/);
        if (match) {
          width = parseInt(match[1]);
          height = parseInt(match[2]);
        }
      } catch (e) {
        // ImageMagick not available, skip dimension check
      }

      // Calculate estimated VRAM (RGBA)
      const vram = width * height * 4;
      this.totalVRAM += vram;

      // Check file size
      if (fileSize > 10 * 1024 * 1024) { // >10MB
        result.issues.push(`Large file size: ${(fileSize / 1024 / 1024).toFixed(1)}MB`);
        result.recommendations.push('Consider compressing or using a different format');
        result.score -= 20;
      }

      // Check dimensions
      if (width > CONFIG.maxTextureSize || height > CONFIG.maxTextureSize) {
        result.issues.push(`Texture too large: ${width}x${height} (max: ${CONFIG.maxTextureSize}x${CONFIG.maxTextureSize})`);
        result.recommendations.push(`Resize to ${CONFIG.maxTextureSize}x${CONFIG.maxTextureSize} or smaller`);
        result.score -= 30;
      }

      // Check if power of two
      if (width > 0 && height > 0) {
        if (!this.isPowerOfTwo(width) || !this.isPowerOfTwo(height)) {
          result.issues.push('Texture dimensions not power of two');
          result.recommendations.push('Resize to nearest power of two (e.g., 512x512, 1024x1024)');
          result.score -= 15;
        }
      }

      // Check format
      if (ext === '.png' || ext === '.jpg' || ext === '.jpeg') {
        result.recommendations.push('Consider using WebP for better compression');
        result.score -= 10;
      }

      // Check VRAM usage
      if (vram > 16 * 1024 * 1024) { // >16MB
        result.issues.push(`High VRAM usage: ${(vram / 1024 / 1024).toFixed(1)}MB`);
        result.recommendations.push('Use compressed texture format (WebP, Basis, or KTX2)');
        result.score -= 20;
      }

    } catch (error) {
      result.issues.push(`Error reading file: ${error.message}`);
      result.score = 0;
    }

    result.score = Math.max(0, result.score);
    this.auditResults.push(result);
    return result;
  }

  /**
   * Run full audit
   */
  audit() {
    this.scanForTextures();
    
    console.log('\n=== Texture Audit Results ===\n');
    
    let totalScore = 0;
    let issuesFound = 0;
    
    for (const file of this.textureFiles) {
      const result = this.auditTexture(file);
      totalScore += result.score;
      issuesFound += result.issues.length;
      
      if (result.issues.length > 0) {
        console.log(`\n${result.file}:`);
        console.log(`  Score: ${result.score}/100`);
        result.issues.forEach(issue => console.log(`  ⚠️  ${issue}`));
        result.recommendations.forEach(rec => console.log(`  💡 ${rec}`));
      }
    }

    // Summary
    console.log('\n=== Audit Summary ===');
    console.log(`Total textures: ${this.textureFiles.length}`);
    console.log(`Total VRAM: ${(this.totalVRAM / 1024 / 1024).toFixed(1)}MB`);
    console.log(`Average score: ${(totalScore / this.textureFiles.length).toFixed(1)}/100`);
    console.log(`Issues found: ${issuesFound}`);
    console.log(`Texture limit: ${this.textureFiles.length > CONFIG.maxTotalTextures ? 'EXCEEDED' : 'OK'}`);
    console.log(`VRAM limit: ${this.totalVRAM > CONFIG.maxTotalVRAM ? 'EXCEEDED' : 'OK'}`);

    // Generate compression plan
    this.generateCompressionPlan();
  }

  /**
   * Generate compression plan
   */
  generateCompressionPlan() {
    console.log('\n=== Compression Plan ===');
    
    const webpCandidates = [];
    const resizeCandidates = [];
    
    for (const result of this.auditResults) {
      if (result.score < 80) {
        const ext = path.extname(result.file).toLowerCase();
        
        if (ext === '.png' || ext === '.jpg' || ext === '.jpeg') {
          webpCandidates.push(result.file);
        }
        
        if (result.issues.some(i => i.includes('too large'))) {
          resizeCandidates.push(result.file);
        }
      }
    }

    console.log(`Textures to convert to WebP: ${webpCandidates.length}`);
    webpCandidates.forEach(f => console.log(`  📦 ${f}`));
    
    console.log(`Textures to resize: ${resizeCandidates.length}`);
    resizeCandidates.forEach(f => console.log(`  📐 ${f}`));

    if (webpCandidates.length > 0) {
      console.log('\nTo convert to WebP:');
      console.log('  for file in *.png; do cwebp -q 80 "$file" -o "${file%.png}.webp"; done');
    }
  }

  /**
   * Check if number is power of two
   */
  isPowerOfTwo(n) {
    return n !== 0 && (n & (n - 1)) === 0;
  }

  /**
   * Save audit results to JSON
   */
  saveResults(outputPath) {
    const report = {
      timestamp: new Date().toISOString(),
      projectRoot: this.projectRoot,
      totalTextures: this.textureFiles.length,
      totalVRAM: this.totalVRAM,
      averageScore: this.auditResults.reduce((sum, r) => sum + r.score, 0) / this.auditResults.length,
      results: this.auditResults,
    };
    
    fs.writeFileSync(outputPath, JSON.stringify(report, null, 2));
    console.log(`\nAudit results saved to: ${outputPath}`);
  }
}

// CLI interface
if (require.main === module) {
  const projectRoot = process.argv[2] || process.cwd();
  const auditor = new TextureAuditor(projectRoot);
  
  auditor.audit();
  
  // Save results if output path provided
  if (process.argv[3]) {
    auditor.saveResults(process.argv[3]);
  }
}

module.exports = TextureAuditor;