import { execSync } from 'child_process';

// Project container names (only manage these)
const PROJECT_CONTAINERS = [
  'paddleocr-vl-test',
  'paddleocr-vl-gpu-test',
  'paddleocr-vl-cpu-test',
  'paddleocr-vl-full-test',
  'minicpm-test',
];

// Image configurations
export interface IImageConfig {
  name: string;
  dockerfile: string;
  buildContext: string;
  containerName: string;
  ports: string[];
  volumes?: string[];
  gpus?: boolean;
  healthEndpoint?: string;
  healthTimeout?: number;
}

export const IMAGES = {
  paddleocrVlGpu: {
    name: 'paddleocr-vl-gpu',
    dockerfile: 'Dockerfile_paddleocr_vl_gpu',
    buildContext: '.',
    containerName: 'paddleocr-vl-test',
    ports: ['8000:8000'],
    volumes: ['ht-huggingface-cache:/root/.cache/huggingface'],
    gpus: true,
    healthEndpoint: 'http://localhost:8000/health',
    healthTimeout: 300000, // 5 minutes for model loading
  } as IImageConfig,

  paddleocrVlCpu: {
    name: 'paddleocr-vl-cpu',
    dockerfile: 'Dockerfile_paddleocr_vl_cpu',
    buildContext: '.',
    containerName: 'paddleocr-vl-test',
    ports: ['8000:8000'],
    volumes: ['ht-huggingface-cache:/root/.cache/huggingface'],
    gpus: false,
    healthEndpoint: 'http://localhost:8000/health',
    healthTimeout: 300000,
  } as IImageConfig,

  minicpm: {
    name: 'minicpm45v',
    dockerfile: 'Dockerfile_minicpm45v',
    buildContext: '.',
    containerName: 'minicpm-test',
    ports: ['11434:11434'],
    volumes: ['ht-ollama-models:/root/.ollama'],
    gpus: true,
    healthEndpoint: 'http://localhost:11434/api/tags',
    healthTimeout: 120000,
  } as IImageConfig,

  // Full PaddleOCR-VL pipeline with PP-DocLayoutV2 + structured JSON output
  paddleocrVlFull: {
    name: 'paddleocr-vl-full',
    dockerfile: 'Dockerfile_paddleocr_vl_full',
    buildContext: '.',
    containerName: 'paddleocr-vl-full-test',
    ports: ['8000:8000'],
    volumes: [
      'ht-huggingface-cache:/root/.cache/huggingface',
      'ht-paddleocr-cache:/root/.paddleocr',
    ],
    gpus: true,
    healthEndpoint: 'http://localhost:8000/health',
    healthTimeout: 600000, // 10 minutes for model loading (vLLM + PP-DocLayoutV2)
  } as IImageConfig,
};

/**
 * Execute a shell command and return output
 */
function exec(command: string, silent = false): string {
  try {
    return execSync(command, {
      encoding: 'utf-8',
      stdio: silent ? 'pipe' : 'inherit',
    });
  } catch (err: unknown) {
    if (silent) return '';
    throw err;
  }
}

/**
 * Check if a Docker image exists locally
 */
export function imageExists(imageName: string): boolean {
  const result = exec(`docker images -q ${imageName}`, true);
  return result.trim().length > 0;
}

/**
 * Check if a container is running
 */
export function isContainerRunning(containerName: string): boolean {
  const result = exec(`docker ps --filter "name=^${containerName}$" --format "{{.Names}}"`, true);
  return result.trim() === containerName;
}

/**
 * Check if a container exists (running or stopped)
 */
export function containerExists(containerName: string): boolean {
  const result = exec(`docker ps -a --filter "name=^${containerName}$" --format "{{.Names}}"`, true);
  return result.trim() === containerName;
}

/**
 * Stop and remove a container
 */
export function removeContainer(containerName: string): void {
  if (containerExists(containerName)) {
    console.log(`[Docker] Removing container: ${containerName}`);
    exec(`docker rm -f ${containerName}`, true);
  }
}

/**
 * Stop all project containers that conflict with the required one
 */
export function stopConflictingContainers(requiredContainer: string, requiredPort: string): void {
  // Stop project containers using the same port
  for (const container of PROJECT_CONTAINERS) {
    if (container === requiredContainer) continue;

    if (isContainerRunning(container)) {
      // Check if this container uses the same port
      const ports = exec(`docker port ${container} 2>/dev/null || true`, true);
      if (ports.includes(requiredPort.split(':')[0])) {
        console.log(`[Docker] Stopping conflicting container: ${container}`);
        exec(`docker stop ${container}`, true);
      }
    }
  }
}

/**
 * Build a Docker image
 */
export function buildImage(config: IImageConfig): void {
  console.log(`[Docker] Building image: ${config.name}`);
  const cmd = `docker build --load -f ${config.dockerfile} -t ${config.name} ${config.buildContext}`;
  exec(cmd);
}

/**
 * Start a container from an image
 */
export function startContainer(config: IImageConfig): void {
  // Remove existing container if it exists
  removeContainer(config.containerName);

  console.log(`[Docker] Starting container: ${config.containerName}`);

  const portArgs = config.ports.map((p) => `-p ${p}`).join(' ');
  const volumeArgs = config.volumes?.map((v) => `-v ${v}`).join(' ') || '';
  const gpuArgs = config.gpus ? '--gpus all' : '';

  const cmd = `docker run -d --name ${config.containerName} ${gpuArgs} ${portArgs} ${volumeArgs} ${config.name}`;
  exec(cmd);
}

/**
 * Wait for a container to become healthy
 */
export async function waitForHealth(
  endpoint: string,
  timeoutMs: number = 120000,
  intervalMs: number = 5000
): Promise<boolean> {
  const startTime = Date.now();
  console.log(`[Docker] Waiting for health: ${endpoint}`);

  while (Date.now() - startTime < timeoutMs) {
    try {
      const response = await fetch(endpoint, {
        method: 'GET',
        signal: AbortSignal.timeout(5000),
      });
      if (response.ok) {
        console.log(`[Docker] Service healthy!`);
        return true;
      }
    } catch {
      // Service not ready yet
    }

    const elapsed = Math.round((Date.now() - startTime) / 1000);
    console.log(`[Docker] Waiting... (${elapsed}s)`);
    await new Promise((resolve) => setTimeout(resolve, intervalMs));
  }

  console.log(`[Docker] Health check timeout after ${timeoutMs / 1000}s`);
  return false;
}

/**
 * Ensure a service is running and healthy
 * - Builds image if missing
 * - Stops conflicting project containers
 * - Starts container if not running
 * - Waits for health check
 */
export async function ensureService(config: IImageConfig): Promise<boolean> {
  console.log(`\n[Docker] Ensuring service: ${config.name}`);

  // Build image if it doesn't exist
  if (!imageExists(config.name)) {
    console.log(`[Docker] Image not found, building...`);
    buildImage(config);
  }

  // Stop conflicting containers on the same port
  const mainPort = config.ports[0];
  stopConflictingContainers(config.containerName, mainPort);

  // Start container if not running
  if (!isContainerRunning(config.containerName)) {
    startContainer(config);
  } else {
    console.log(`[Docker] Container already running: ${config.containerName}`);
  }

  // Wait for health
  if (config.healthEndpoint) {
    return waitForHealth(config.healthEndpoint, config.healthTimeout);
  }

  return true;
}

/**
 * Ensure PaddleOCR-VL GPU service is running
 */
export async function ensurePaddleOcrVlGpu(): Promise<boolean> {
  return ensureService(IMAGES.paddleocrVlGpu);
}

/**
 * Ensure PaddleOCR-VL CPU service is running
 */
export async function ensurePaddleOcrVlCpu(): Promise<boolean> {
  return ensureService(IMAGES.paddleocrVlCpu);
}

/**
 * Ensure MiniCPM service is running
 */
export async function ensureMiniCpm(): Promise<boolean> {
  return ensureService(IMAGES.minicpm);
}

/**
 * Check if GPU is available
 */
export function isGpuAvailable(): boolean {
  try {
    const result = exec('nvidia-smi --query-gpu=name --format=csv,noheader 2>/dev/null', true);
    return result.trim().length > 0;
  } catch {
    return false;
  }
}

/**
 * Ensure PaddleOCR-VL service (auto-detect GPU/CPU)
 */
export async function ensurePaddleOcrVl(): Promise<boolean> {
  if (isGpuAvailable()) {
    console.log('[Docker] GPU detected, using GPU image');
    return ensurePaddleOcrVlGpu();
  } else {
    console.log('[Docker] No GPU detected, using CPU image');
    return ensurePaddleOcrVlCpu();
  }
}

/**
 * Ensure PaddleOCR-VL Full Pipeline service (PP-DocLayoutV2 + structured output)
 * This is the recommended service for production use - outputs structured JSON/Markdown
 */
export async function ensurePaddleOcrVlFull(): Promise<boolean> {
  if (!isGpuAvailable()) {
    console.log('[Docker] WARNING: Full pipeline requires GPU, but none detected');
  }
  return ensureService(IMAGES.paddleocrVlFull);
}