/**
 * QUIXZOOM Video-to-Observation Pipeline
 * 
 * Konverterar video till strukturerade observationer
 */

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

class VideoToObservationPipeline {
  constructor(config = {}) {
    this.config = {
      frameInterval: config.frameInterval || 5,
      outputDir: config.outputDir || '/tmp/video-frames',
      ...config,
    };
    this.observations = [];
  }

  async processVideo(videoPath, metadata = {}) {
    console.log(`[VIDEO] Processing: ${videoPath}`);
    
    const videoInfo = this.extractMetadata(videoPath);
    console.log(`[VIDEO] Duration: ${videoInfo.duration}s`);
    
    const frames = await this.extractFrames(videoPath);
    console.log(`[VIDEO] Extracted ${frames.length} frames`);
    
    for (let i = 0; i < frames.length; i++) {
      const frame = frames[i];
      const timestamp = metadata.startTime 
        ? new Date(metadata.startTime.getTime() + i * this.config.frameInterval * 1000)
        : new Date();
      
      const detectedObjects = this.mockObjectDetection(frame, metadata, i);
      
      for (const obj of detectedObjects) {
        this.observations.push({
          id: `obs_${path.basename(videoPath)}_${i}_${obj.type}`,
          objectType: obj.type,
          location: { lat: obj.lat, lng: obj.lng },
          gpsAccuracy: obj.accuracy,
          timestamp: timestamp,
          attributes: obj.attributes,
          source: {
            type: 'video',
            videoId: metadata.videoId || path.basename(videoPath),
            frameNumber: i,
            timestamp: i * this.config.frameInterval,
          },
          quality: {
            confidence: obj.confidence,
            blur: 0.1,
            exposure: 0.8,
          },
        });
      }
    }
    
    console.log(`[VIDEO] Created ${this.observations.length} observations`);
    return this.observations;
  }

  extractMetadata(videoPath) {
    try {
      const output = execSync(
        `ffprobe -v quiet -print_format json -show_format -show_streams "${videoPath}"`,
        { encoding: 'utf-8', timeout: 10000 }
      );
      const info = JSON.parse(output);
      const stream = info.streams.find(s => s.codec_type === 'video');
      return {
        duration: parseFloat(info.format.duration) || 0,
        width: stream?.width || 0,
        height: stream?.height || 0,
      };
    } catch (error) {
      return { duration: 0, width: 0, height: 0 };
    }
  }

  async extractFrames(videoPath) {
    const outputDir = path.join(this.config.outputDir, path.basename(videoPath, path.extname(videoPath)));
    if (!fs.existsSync(outputDir)) {
      fs.mkdirSync(outputDir, { recursive: true });
    }
    
    const fps = 1 / this.config.frameInterval;
    const outputPattern = path.join(outputDir, 'frame_%04d.jpg');
    
    try {
      execSync(
        `ffmpeg -i "${videoPath}" -vf "fps=${fps}" -q:v 2 "${outputPattern}"`,
        { timeout: 60000, stdio: 'pipe' }
      );
    } catch (error) {
      console.warn(`[VIDEO] ffmpeg failed: ${error.message}`);
      return [];
    }
    
    return fs.readdirSync(outputDir)
      .filter(f => f.endsWith('.jpg'))
      .map(f => path.join(outputDir, f))
      .sort();
  }

  mockObjectDetection(framePath, metadata = {}, frameIndex) {
    const objects = [];
    const bangkokObjects = [
      { type: 'street_lamp', probability: 0.7 },
      { type: 'traffic_sign', probability: 0.4 },
      { type: 'tree', probability: 0.6 },
      { type: 'utility_box', probability: 0.2 },
      { type: 'manhole', probability: 0.3 },
    ];
    
    const numObjects = 1 + Math.floor(Math.random() * 3);
    
    for (let i = 0; i < numObjects; i++) {
      const template = bangkokObjects[Math.floor(Math.random() * bangkokObjects.length)];
      
      if (Math.random() < template.probability) {
        const baseLat = metadata.baseLat || 13.7563;
        const baseLng = metadata.baseLng || 100.5018;
        const drift = frameIndex * 0.0001;
        
        objects.push({
          type: template.type,
          lat: baseLat + (Math.random() - 0.5) * 0.001 + drift,
          lng: baseLng + (Math.random() - 0.5) * 0.001 + drift * 0.5,
          accuracy: 2 + Math.random() * 3,
          confidence: 0.6 + Math.random() * 0.35,
          attributes: this.generateAttributes(template.type),
        });
      }
    }
    
    return objects;
  }

  generateAttributes(objectType) {
    const attributes = {
      street_lamp: {
        height: 7 + Math.random() * 3,
        material: ['steel', 'aluminum'][Math.floor(Math.random() * 2)],
        paint: ['grey', 'black', 'green'][Math.floor(Math.random() * 3)],
        light: Math.random() > 0.9 ? 'broken' : 'working',
      },
      traffic_sign: {
        signType: ['speed_limit', 'stop', 'pedestrian'][Math.floor(Math.random() * 3)],
        height: 2 + Math.random() * 1,
        reflective: Math.random() > 0.1,
      },
      tree: {
        species: ['palm', 'banyan', 'eucalyptus'][Math.floor(Math.random() * 3)],
        height: 5 + Math.random() * 10,
        health: Math.random() > 0.9 ? 'poor' : 'good',
      },
      utility_box: {
        type: ['electric', 'telecom'][Math.floor(Math.random() * 2)],
        condition: Math.random() > 0.85 ? 'damaged' : 'good',
      },
      manhole: {
        diameter: 0.5 + Math.random() * 0.3,
        material: ['cast_iron', 'concrete'][Math.floor(Math.random() * 2)],
      },
    };
    
    return attributes[objectType] || {};
  }

  saveToFile(outputPath) {
    const data = {
      version: '1.0',
      generatedAt: new Date().toISOString(),
      observationCount: this.observations.length,
      observations: this.observations,
    };
    fs.writeFileSync(outputPath, JSON.stringify(data, null, 2));
    console.log(`[VIDEO] Saved to ${outputPath}`);
  }
}

module.exports = VideoToObservationPipeline;