/**
 * Docker Manager for Onebox
 *
 * Handles all Docker operations: containers, images, networks, volumes
 */

import * as plugins from '../plugins.ts';
import type { IService, IContainerStats } from '../types.ts';
import { logger } from '../logging.ts';

export class OneboxDockerManager {
  private dockerClient: plugins.docker.Docker | null = null;
  private networkName = 'onebox-network';

  /**
   * Initialize Docker client and create onebox network
   */
  async init(): Promise<void> {
    try {
      // Initialize Docker client (connects to /var/run/docker.sock by default)
      this.dockerClient = new plugins.docker.Docker({
        socketPath: 'unix:///var/run/docker.sock',
      });

      // Start the Docker client
      await this.dockerClient.start();

      logger.info('Docker client initialized');

      // Ensure onebox network exists
      await this.ensureNetwork();
    } catch (error) {
      logger.error(`Failed to initialize Docker client: ${error.message}`);
      throw error;
    }
  }

  /**
   * Ensure onebox network exists
   */
  private async ensureNetwork(): Promise<void> {
    try {
      const networks = await this.dockerClient!.getNetworks();
      const existingNetwork = networks.find((n: any) => n.name === this.networkName);

      if (!existingNetwork) {
        logger.info(`Creating Docker network: ${this.networkName}`);

        // Check if Docker is in Swarm mode
        let isSwarmMode = false;
        try {
          const swarmResponse = await this.dockerClient!.request('GET', '/swarm', {});
          isSwarmMode = swarmResponse.statusCode === 200;
        } catch (error) {
          isSwarmMode = false;
        }

        await this.dockerClient!.createNetwork({
          Name: this.networkName,
          Driver: isSwarmMode ? 'overlay' : 'bridge',
          Attachable: isSwarmMode ? true : undefined, // Required for overlay networks to allow standalone containers
          Labels: {
            'managed-by': 'onebox',
          },
        });
        logger.success(`Docker network created: ${this.networkName} (${isSwarmMode ? 'overlay' : 'bridge'})`);
      } else {
        logger.debug(`Docker network already exists: ${this.networkName}`);
      }
    } catch (error) {
      logger.error(`Failed to create Docker network: ${error.message}`);
      throw error;
    }
  }

  /**
   * Pull an image from a registry
   */
  async pullImage(image: string, registry?: string): Promise<void> {
    // Skip manual image pulling - Docker will automatically pull when creating container
    const fullImage = registry ? `${registry}/${image}` : image;
    logger.debug(`Skipping manual pull for ${fullImage} - Docker will auto-pull on container creation`);
  }

  /**
   * Create and start a container or service (depending on Swarm mode)
   */
  async createContainer(service: IService): Promise<string> {
    try {
      // Check if Docker is in Swarm mode
      let isSwarmMode = false;
      try {
        const swarmResponse = await this.dockerClient!.request('GET', '/swarm', {});
        isSwarmMode = swarmResponse.statusCode === 200;
      } catch (error) {
        isSwarmMode = false;
      }

      if (isSwarmMode) {
        return await this.createSwarmService(service);
      } else {
        return await this.createStandaloneContainer(service);
      }
    } catch (error) {
      logger.error(`Failed to create container for ${service.name}: ${error.message}`);
      throw error;
    }
  }

  /**
   * Create a standalone container (non-Swarm mode)
   */
  private async createStandaloneContainer(service: IService): Promise<string> {
    logger.info(`Creating standalone container for service: ${service.name}`);

    const fullImage = service.registry
      ? `${service.registry}/${service.image}`
      : service.image;

    // Prepare environment variables
    const env: string[] = [];
    for (const [key, value] of Object.entries(service.envVars)) {
      env.push(`${key}=${value}`);
    }

    // Create container using Docker REST API directly
    const response = await this.dockerClient!.request('POST', `/containers/create?name=onebox-${service.name}`, {
      Image: fullImage,
      Env: env,
      Labels: {
        'managed-by': 'onebox',
        'onebox-service': service.name,
      },
      ExposedPorts: {
        [`${service.port}/tcp`]: {},
      },
      HostConfig: {
        NetworkMode: this.networkName,
        RestartPolicy: {
          Name: 'unless-stopped',
        },
        PortBindings: {
          // Don't bind to host ports - nginx will proxy
          [`${service.port}/tcp`]: [],
        },
      },
    });

    if (response.statusCode >= 300) {
      throw new Error(`Failed to create container: HTTP ${response.statusCode}`);
    }

    const containerID = response.body.Id;
    logger.success(`Standalone container created: ${containerID}`);

    return containerID;
  }

  /**
   * Create a Docker Swarm service
   */
  private async createSwarmService(service: IService): Promise<string> {
    logger.info(`Creating Swarm service for: ${service.name}`);

    const fullImage = service.registry
      ? `${service.registry}/${service.image}`
      : service.image;

    // Prepare environment variables
    const env: string[] = [];
    for (const [key, value] of Object.entries(service.envVars)) {
      env.push(`${key}=${value}`);
    }

    // Create Swarm service using Docker REST API
    const response = await this.dockerClient!.request('POST', '/services/create', {
      Name: `onebox-${service.name}`,
      Labels: {
        'managed-by': 'onebox',
        'onebox-service': service.name,
      },
      TaskTemplate: {
        ContainerSpec: {
          Image: fullImage,
          Env: env,
          Labels: {
            'managed-by': 'onebox',
            'onebox-service': service.name,
          },
        },
        Networks: [
          {
            Target: await this.getNetworkID(this.networkName),
          },
        ],
        RestartPolicy: {
          Condition: 'any',
          MaxAttempts: 0,
        },
      },
      Mode: {
        Replicated: {
          Replicas: 1,
        },
      },
      EndpointSpec: {
        Ports: [
          {
            Protocol: 'tcp',
            TargetPort: service.port,
            PublishMode: 'host',
          },
        ],
      },
    });

    if (response.statusCode >= 300) {
      throw new Error(`Failed to create service: HTTP ${response.statusCode} - ${JSON.stringify(response.body)}`);
    }

    const serviceID = response.body.ID;
    logger.success(`Swarm service created: ${serviceID}`);

    return serviceID;
  }

  /**
   * Get network ID by name
   */
  private async getNetworkID(networkName: string): Promise<string> {
    const networks = await this.dockerClient!.getNetworks();
    const network = networks.find((n: any) =>
      (n.name || n.Name) === networkName
    );
    if (!network) {
      throw new Error(`Network not found: ${networkName}`);
    }
    return network.id || network.Id;
  }

  /**
   * Start a container or service by ID
   */
  async startContainer(containerID: string): Promise<void> {
    try {
      // Try service first
      if (await this.isService(containerID)) {
        return await this.startService(containerID);
      }

      logger.info(`Starting container: ${containerID}`);

      const response = await this.dockerClient!.request('POST', `/containers/${containerID}/start`, {});

      if (response.statusCode >= 300 && response.statusCode !== 304) {
        throw new Error(`Failed to start container: HTTP ${response.statusCode}`);
      }

      logger.success(`Container started: ${containerID}`);
    } catch (error) {
      // Ignore "already started" errors (304 status)
      if (error.message.includes('304')) {
        logger.debug(`Container already running: ${containerID}`);
        return;
      }
      logger.error(`Failed to start container ${containerID}: ${error.message}`);
      throw error;
    }
  }

  /**
   * Start a Swarm service (scale to 1 replica)
   */
  private async startService(serviceID: string): Promise<void> {
    logger.info(`Starting service: ${serviceID}`);

    // Get current service spec
    const getResponse = await this.dockerClient!.request('GET', `/services/${serviceID}`, {});
    if (getResponse.statusCode >= 300) {
      throw new Error(`Failed to get service: HTTP ${getResponse.statusCode}`);
    }

    const service = getResponse.body;
    const version = service.Version.Index;

    // Update service to scale to 1 replica
    const updateResponse = await this.dockerClient!.request('POST', `/services/${serviceID}/update?version=${version}`, {
      ...service.Spec,
      Mode: {
        Replicated: {
          Replicas: 1,
        },
      },
    });

    if (updateResponse.statusCode >= 300) {
      throw new Error(`Failed to start service: HTTP ${updateResponse.statusCode}`);
    }

    logger.success(`Service started (scaled to 1 replica): ${serviceID}`);
  }

  /**
   * Check if ID is a service (not a container)
   */
  private async isService(id: string): Promise<boolean> {
    try {
      const response = await this.dockerClient!.request('GET', `/services/${id}`, {});
      return response.statusCode === 200;
    } catch (error) {
      return false;
    }
  }

  /**
   * Stop a container or service by ID
   */
  async stopContainer(containerID: string): Promise<void> {
    try {
      // Try service first
      if (await this.isService(containerID)) {
        return await this.stopService(containerID);
      }

      logger.info(`Stopping container: ${containerID}`);

      const response = await this.dockerClient!.request('POST', `/containers/${containerID}/stop`, {});

      if (response.statusCode >= 300 && response.statusCode !== 304) {
        throw new Error(`Failed to stop container: HTTP ${response.statusCode}`);
      }

      logger.success(`Container stopped: ${containerID}`);
    } catch (error) {
      // Ignore "already stopped" errors (304 status)
      if (error.message.includes('304')) {
        logger.debug(`Container already stopped: ${containerID}`);
        return;
      }
      logger.error(`Failed to stop container ${containerID}: ${error.message}`);
      throw error;
    }
  }

  /**
   * Stop a Swarm service (scale to 0 replicas)
   */
  private async stopService(serviceID: string): Promise<void> {
    logger.info(`Stopping service: ${serviceID}`);

    // Get current service spec
    const getResponse = await this.dockerClient!.request('GET', `/services/${serviceID}`, {});
    if (getResponse.statusCode >= 300) {
      throw new Error(`Failed to get service: HTTP ${getResponse.statusCode}`);
    }

    const service = getResponse.body;
    const version = service.Version.Index;

    // Update service to scale to 0 replicas
    const updateResponse = await this.dockerClient!.request('POST', `/services/${serviceID}/update?version=${version}`, {
      ...service.Spec,
      Mode: {
        Replicated: {
          Replicas: 0,
        },
      },
    });

    if (updateResponse.statusCode >= 300) {
      throw new Error(`Failed to stop service: HTTP ${updateResponse.statusCode}`);
    }

    logger.success(`Service stopped (scaled to 0 replicas): ${serviceID}`);
  }

  /**
   * Restart a container or service by ID
   */
  async restartContainer(containerID: string): Promise<void> {
    try {
      // Try service first
      if (await this.isService(containerID)) {
        return await this.restartService(containerID);
      }

      logger.info(`Restarting container: ${containerID}`);

      const response = await this.dockerClient!.request('POST', `/containers/${containerID}/restart`, {});

      if (response.statusCode >= 300) {
        throw new Error(`Failed to restart container: HTTP ${response.statusCode}`);
      }

      logger.success(`Container restarted: ${containerID}`);
    } catch (error) {
      logger.error(`Failed to restart container ${containerID}: ${error.message}`);
      throw error;
    }
  }

  /**
   * Restart a Swarm service (force update with same spec)
   */
  private async restartService(serviceID: string): Promise<void> {
    logger.info(`Restarting service: ${serviceID}`);

    // Get current service spec
    const getResponse = await this.dockerClient!.request('GET', `/services/${serviceID}`, {});
    if (getResponse.statusCode >= 300) {
      throw new Error(`Failed to get service: HTTP ${getResponse.statusCode}`);
    }

    const service = getResponse.body;
    const version = service.Version.Index;

    // Force update to trigger restart
    const updateResponse = await this.dockerClient!.request('POST', `/services/${serviceID}/update?version=${version}`, {
      ...service.Spec,
      TaskTemplate: {
        ...service.Spec.TaskTemplate,
        ForceUpdate: (service.Spec.TaskTemplate.ForceUpdate || 0) + 1,
      },
    });

    if (updateResponse.statusCode >= 300) {
      throw new Error(`Failed to restart service: HTTP ${updateResponse.statusCode}`);
    }

    logger.success(`Service restarted: ${serviceID}`);
  }

  /**
   * Remove a container or service by ID
   */
  async removeContainer(containerID: string, force = false): Promise<void> {
    try {
      // Try service first
      if (await this.isService(containerID)) {
        return await this.removeService(containerID);
      }

      logger.info(`Removing container: ${containerID}`);

      // Stop first if not forced
      if (!force) {
        try {
          await this.stopContainer(containerID);
        } catch (error) {
          // Ignore stop errors
          logger.debug(`Error stopping container before removal: ${error.message}`);
        }
      }

      const url = force ? `/containers/${containerID}?force=true` : `/containers/${containerID}`;
      const response = await this.dockerClient!.request('DELETE', url, {});

      if (response.statusCode >= 300) {
        throw new Error(`Failed to remove container: HTTP ${response.statusCode}`);
      }

      logger.success(`Container removed: ${containerID}`);
    } catch (error) {
      logger.error(`Failed to remove container ${containerID}: ${error.message}`);
      throw error;
    }
  }

  /**
   * Remove a Swarm service
   */
  private async removeService(serviceID: string): Promise<void> {
    logger.info(`Removing service: ${serviceID}`);

    const response = await this.dockerClient!.request('DELETE', `/services/${serviceID}`, {});

    if (response.statusCode >= 300) {
      throw new Error(`Failed to remove service: HTTP ${response.statusCode}`);
    }

    logger.success(`Service removed: ${serviceID}`);
  }

  /**
   * Get container or service status
   */
  async getContainerStatus(containerID: string): Promise<string> {
    try {
      // Try service first
      if (await this.isService(containerID)) {
        return await this.getServiceStatus(containerID);
      }

      const response = await this.dockerClient!.request('GET', `/containers/${containerID}/json`, {});

      if (response.statusCode >= 300) {
        return 'unknown';
      }

      return response.body.State?.Status || 'unknown';
    } catch (error) {
      logger.error(`Failed to get container status ${containerID}: ${error.message}`);
      return 'unknown';
    }
  }

  /**
   * Get Swarm service status
   */
  private async getServiceStatus(serviceID: string): Promise<string> {
    try {
      // Get service details
      const serviceResponse = await this.dockerClient!.request('GET', `/services/${serviceID}`, {});
      if (serviceResponse.statusCode >= 300) {
        return 'unknown';
      }

      const service = serviceResponse.body;
      const replicas = service.Spec?.Mode?.Replicated?.Replicas || 0;

      if (replicas === 0) {
        return 'stopped';
      }

      // Get tasks for this service to check if they're running
      const tasksResponse = await this.dockerClient!.request('GET', `/tasks?filters=${encodeURIComponent(JSON.stringify({service: [serviceID]}))}`, {});
      if (tasksResponse.statusCode >= 300) {
        return 'unknown';
      }

      const tasks = tasksResponse.body;
      if (tasks.length === 0) {
        return 'starting';
      }

      // Check if any task is running
      const hasRunning = tasks.some((task: any) => task.Status?.State === 'running');
      if (hasRunning) {
        return 'running';
      }

      // Check task states
      const latestTask = tasks[0];
      const taskState = latestTask?.Status?.State || 'unknown';

      // Map Swarm task states to container-like states
      switch (taskState) {
        case 'new':
        case 'allocated':
        case 'pending':
        case 'assigned':
        case 'accepted':
        case 'preparing':
        case 'ready':
        case 'starting':
          return 'starting';
        case 'running':
          return 'running';
        case 'complete':
          return 'exited';
        case 'failed':
        case 'shutdown':
        case 'rejected':
        case 'orphaned':
        case 'remove':
          return 'stopped';
        default:
          return 'unknown';
      }
    } catch (error) {
      logger.error(`Failed to get service status ${serviceID}: ${error.message}`);
      return 'unknown';
    }
  }

  /**
   * Get container stats (CPU, memory, network)
   */
  async getContainerStats(containerID: string): Promise<IContainerStats | null> {
    try {
      const container = this.dockerClient!.getContainer(containerID);
      const stats = await container.stats({ stream: false });

      // Calculate CPU percentage
      const cpuDelta =
        stats.cpu_stats.cpu_usage.total_usage - stats.precpu_stats.cpu_usage.total_usage;
      const systemDelta = stats.cpu_stats.system_cpu_usage - stats.precpu_stats.system_cpu_usage;
      const cpuPercent =
        systemDelta > 0 ? (cpuDelta / systemDelta) * stats.cpu_stats.online_cpus * 100 : 0;

      // Memory stats
      const memoryUsed = stats.memory_stats.usage || 0;
      const memoryLimit = stats.memory_stats.limit || 0;
      const memoryPercent = memoryLimit > 0 ? (memoryUsed / memoryLimit) * 100 : 0;

      // Network stats
      let networkRx = 0;
      let networkTx = 0;
      if (stats.networks) {
        for (const network of Object.values(stats.networks)) {
          networkRx += (network as any).rx_bytes || 0;
          networkTx += (network as any).tx_bytes || 0;
        }
      }

      return {
        cpuPercent,
        memoryUsed,
        memoryLimit,
        memoryPercent,
        networkRx,
        networkTx,
      };
    } catch (error) {
      logger.error(`Failed to get container stats ${containerID}: ${error.message}`);
      return null;
    }
  }

  /**
   * Get container logs
   */
  async getContainerLogs(
    containerID: string,
    tail = 100
  ): Promise<{ stdout: string; stderr: string }> {
    try {
      const container = this.dockerClient!.getContainer(containerID);
      const logs = await container.logs({
        stdout: true,
        stderr: true,
        tail,
        timestamps: true,
      });

      // Parse logs (Docker returns them in a special format)
      const stdout: string[] = [];
      const stderr: string[] = [];

      const lines = logs.toString().split('\n');
      for (const line of lines) {
        if (line.length === 0) continue;

        // Docker log format: first byte indicates stream (1=stdout, 2=stderr)
        const streamType = line.charCodeAt(0);
        const content = line.slice(8); // Skip header (8 bytes)

        if (streamType === 1) {
          stdout.push(content);
        } else if (streamType === 2) {
          stderr.push(content);
        }
      }

      return {
        stdout: stdout.join('\n'),
        stderr: stderr.join('\n'),
      };
    } catch (error) {
      logger.error(`Failed to get container logs ${containerID}: ${error.message}`);
      return { stdout: '', stderr: '' };
    }
  }

  /**
   * Stream container logs (real-time)
   */
  async streamContainerLogs(
    containerID: string,
    callback: (line: string, isError: boolean) => void
  ): Promise<void> {
    try {
      const container = this.dockerClient!.getContainer(containerID);
      const stream = await container.logs({
        stdout: true,
        stderr: true,
        follow: true,
        tail: 0,
        timestamps: true,
      });

      stream.on('data', (chunk: Buffer) => {
        const streamType = chunk[0];
        const content = chunk.slice(8).toString();
        callback(content, streamType === 2);
      });

      stream.on('error', (error: Error) => {
        logger.error(`Log stream error for ${containerID}: ${error.message}`);
      });
    } catch (error) {
      logger.error(`Failed to stream container logs ${containerID}: ${error.message}`);
      throw error;
    }
  }

  /**
   * List all onebox-managed containers
   */
  async listContainers(): Promise<any[]> {
    try {
      const containers = await this.dockerClient!.getContainers();
      // Filter for onebox-managed containers
      return containers.filter((c: any) =>
        c.labels && c.labels['managed-by'] === 'onebox'
      );
    } catch (error) {
      logger.error(`Failed to list containers: ${error.message}`);
      return [];
    }
  }

  /**
   * Check if Docker is running
   */
  async isDockerRunning(): Promise<boolean> {
    try {
      await this.dockerClient!.ping();
      return true;
    } catch (error) {
      return false;
    }
  }

  /**
   * Get Docker version info
   */
  async getDockerVersion(): Promise<any> {
    try {
      return await this.dockerClient!.version();
    } catch (error) {
      logger.error(`Failed to get Docker version: ${error.message}`);
      return null;
    }
  }

  /**
   * Prune unused images
   */
  async pruneImages(): Promise<void> {
    try {
      logger.info('Pruning unused Docker images...');
      await this.dockerClient!.pruneImages();
      logger.success('Unused images pruned successfully');
    } catch (error) {
      logger.error(`Failed to prune images: ${error.message}`);
      throw error;
    }
  }

  /**
   * Get container IP address in onebox network
   */
  async getContainerIP(containerID: string): Promise<string | null> {
    try {
      const container = this.dockerClient!.getContainer(containerID);
      const info = await container.inspect();

      const networks = info.NetworkSettings.Networks;
      if (networks && networks[this.networkName]) {
        return networks[this.networkName].IPAddress;
      }

      return null;
    } catch (error) {
      logger.error(`Failed to get container IP ${containerID}: ${error.message}`);
      return null;
    }
  }

  /**
   * Execute a command in a running container
   */
  async execInContainer(
    containerID: string,
    cmd: string[]
  ): Promise<{ stdout: string; stderr: string; exitCode: number }> {
    try {
      const container = this.dockerClient!.getContainer(containerID);

      const exec = await container.exec({
        Cmd: cmd,
        AttachStdout: true,
        AttachStderr: true,
      });

      const stream = await exec.start({ Detach: false });

      let stdout = '';
      let stderr = '';

      stream.on('data', (chunk: Buffer) => {
        const streamType = chunk[0];
        const content = chunk.slice(8).toString();

        if (streamType === 1) {
          stdout += content;
        } else if (streamType === 2) {
          stderr += content;
        }
      });

      // Wait for completion
      await new Promise((resolve) => stream.on('end', resolve));

      const inspect = await exec.inspect();
      const exitCode = inspect.ExitCode || 0;

      return { stdout, stderr, exitCode };
    } catch (error) {
      logger.error(`Failed to exec in container ${containerID}: ${error.message}`);
      throw error;
    }
  }
}