import * as fs from 'node:fs';
import * as os from 'node:os';
import process from 'node:process';
import { execFile } from 'node:child_process';
import { promisify } from 'node:util';
import { Action, type IActionContext } from './base-action.ts';
import { logger } from '../logger.ts';
import { PROXMOX, UI } from '../constants.ts';

const execFileAsync = promisify(execFile);

/**
 * ProxmoxAction - Gracefully shuts down Proxmox VMs and LXC containers
 *
 * Supports two operation modes:
 * - CLI mode: Uses qm/pct commands directly (requires running as root on a Proxmox host)
 * - API mode: Uses the Proxmox REST API via HTTPS with API token authentication
 *
 * In 'auto' mode (default), CLI is preferred when available, falling back to API.
 *
 * This action should be placed BEFORE shutdown actions in the action chain
 * so that VMs are stopped before the host is shut down.
 */
export class ProxmoxAction extends Action {
  readonly type = 'proxmox';

  /**
   * Check if Proxmox CLI tools (qm, pct) are available on the system
   * Used by CLI wizards and by execute() for auto-detection
   */
  static detectCliAvailability(): {
    available: boolean;
    qmPath: string | null;
    pctPath: string | null;
    isRoot: boolean;
  } {
    let qmPath: string | null = null;
    let pctPath: string | null = null;

    for (const dir of PROXMOX.CLI_TOOL_PATHS) {
      if (!qmPath) {
        const p = `${dir}/qm`;
        try {
          if (fs.existsSync(p)) qmPath = p;
        } catch (_e) {
          // continue
        }
      }
      if (!pctPath) {
        const p = `${dir}/pct`;
        try {
          if (fs.existsSync(p)) pctPath = p;
        } catch (_e) {
          // continue
        }
      }
    }

    const isRoot = !!(process.getuid && process.getuid() === 0);

    return {
      available: qmPath !== null && pctPath !== null && isRoot,
      qmPath,
      pctPath,
      isRoot,
    };
  }

  /**
   * Resolve the operation mode based on config and environment
   */
  private resolveMode(): { mode: 'api' | 'cli'; qmPath: string; pctPath: string } | { mode: 'api'; qmPath?: undefined; pctPath?: undefined } {
    const configuredMode = this.config.proxmoxMode || 'auto';

    if (configuredMode === 'api') {
      return { mode: 'api' };
    }

    const detection = ProxmoxAction.detectCliAvailability();

    if (configuredMode === 'cli') {
      if (!detection.qmPath || !detection.pctPath) {
        throw new Error('CLI mode requested but qm/pct not found. Are you on a Proxmox host?');
      }
      if (!detection.isRoot) {
        throw new Error('CLI mode requires root access');
      }
      return { mode: 'cli', qmPath: detection.qmPath, pctPath: detection.pctPath };
    }

    // Auto-detect
    if (detection.available && detection.qmPath && detection.pctPath) {
      return { mode: 'cli', qmPath: detection.qmPath, pctPath: detection.pctPath };
    }
    return { mode: 'api' };
  }

  /**
   * Execute the Proxmox shutdown action
   */
  async execute(context: IActionContext): Promise<void> {
    if (!this.shouldExecute(context)) {
      logger.info(
        `Proxmox action skipped (trigger mode: ${
          this.config.triggerMode || 'powerChangesAndThresholds'
        })`,
      );
      return;
    }

    const resolved = this.resolveMode();
    const node = this.config.proxmoxNode || os.hostname();
    const excludeIds = new Set(this.config.proxmoxExcludeIds || []);
    const stopTimeout = (this.config.proxmoxStopTimeout || PROXMOX.DEFAULT_STOP_TIMEOUT_SECONDS) * 1000;
    const forceStop = this.config.proxmoxForceStop !== false; // default true

    logger.log('');
    logger.logBoxTitle('Proxmox VM Shutdown', UI.WIDE_BOX_WIDTH, 'warning');
    logger.logBoxLine(`Mode: ${resolved.mode === 'cli' ? 'CLI (qm/pct)' : 'API (REST)'}`);
    logger.logBoxLine(`Node: ${node}`);
    if (resolved.mode === 'api') {
      const host = this.config.proxmoxHost || PROXMOX.DEFAULT_HOST;
      const port = this.config.proxmoxPort || PROXMOX.DEFAULT_PORT;
      logger.logBoxLine(`API: ${host}:${port}`);
    }
    logger.logBoxLine(`UPS: ${context.upsName} (${context.powerStatus})`);
    logger.logBoxLine(`Trigger: ${context.triggerReason}`);
    if (excludeIds.size > 0) {
      logger.logBoxLine(`Excluded IDs: ${[...excludeIds].join(', ')}`);
    }
    logger.logBoxEnd();
    logger.log('');

    try {
      let runningVMs: Array<{ vmid: number; name: string }>;
      let runningCTs: Array<{ vmid: number; name: string }>;

      if (resolved.mode === 'cli') {
        runningVMs = await this.getRunningVMsCli(resolved.qmPath);
        runningCTs = await this.getRunningCTsCli(resolved.pctPath);
      } else {
        // API mode - validate token
        const host = this.config.proxmoxHost || PROXMOX.DEFAULT_HOST;
        const port = this.config.proxmoxPort || PROXMOX.DEFAULT_PORT;
        const tokenId = this.config.proxmoxTokenId;
        const tokenSecret = this.config.proxmoxTokenSecret;
        const insecure = this.config.proxmoxInsecure !== false;

        if (!tokenId || !tokenSecret) {
          logger.error('Proxmox API token ID and secret are required for API mode');
          logger.error('Either provide tokens or run on a Proxmox host as root for CLI mode');
          return;
        }

        const baseUrl = `https://${host}:${port}${PROXMOX.API_BASE}`;
        const headers: Record<string, string> = {
          'Authorization': `PVEAPIToken=${tokenId}=${tokenSecret}`,
        };

        runningVMs = await this.getRunningVMsApi(baseUrl, node, headers, insecure);
        runningCTs = await this.getRunningCTsApi(baseUrl, node, headers, insecure);
      }

      // Filter out excluded IDs
      const vmsToStop = runningVMs.filter((vm) => !excludeIds.has(vm.vmid));
      const ctsToStop = runningCTs.filter((ct) => !excludeIds.has(ct.vmid));

      const totalToStop = vmsToStop.length + ctsToStop.length;
      if (totalToStop === 0) {
        logger.info('No running VMs or containers to shut down');
        return;
      }

      logger.info(`Shutting down ${vmsToStop.length} VMs and ${ctsToStop.length} containers...`);

      // Send shutdown commands
      if (resolved.mode === 'cli') {
        for (const vm of vmsToStop) {
          await this.shutdownVMCli(resolved.qmPath, vm.vmid);
          logger.dim(`  Shutdown sent to VM ${vm.vmid} (${vm.name || 'unnamed'})`);
        }
        for (const ct of ctsToStop) {
          await this.shutdownCTCli(resolved.pctPath, ct.vmid);
          logger.dim(`  Shutdown sent to CT ${ct.vmid} (${ct.name || 'unnamed'})`);
        }
      } else {
        const host = this.config.proxmoxHost || PROXMOX.DEFAULT_HOST;
        const port = this.config.proxmoxPort || PROXMOX.DEFAULT_PORT;
        const insecure = this.config.proxmoxInsecure !== false;
        const baseUrl = `https://${host}:${port}${PROXMOX.API_BASE}`;
        const headers: Record<string, string> = {
          'Authorization': `PVEAPIToken=${this.config.proxmoxTokenId}=${this.config.proxmoxTokenSecret}`,
        };

        for (const vm of vmsToStop) {
          await this.shutdownVMApi(baseUrl, node, vm.vmid, headers, insecure);
          logger.dim(`  Shutdown sent to VM ${vm.vmid} (${vm.name || 'unnamed'})`);
        }
        for (const ct of ctsToStop) {
          await this.shutdownCTApi(baseUrl, node, ct.vmid, headers, insecure);
          logger.dim(`  Shutdown sent to CT ${ct.vmid} (${ct.name || 'unnamed'})`);
        }
      }

      // Poll until all stopped or timeout
      const allIds = [
        ...vmsToStop.map((vm) => ({ type: 'qemu' as const, vmid: vm.vmid, name: vm.name })),
        ...ctsToStop.map((ct) => ({ type: 'lxc' as const, vmid: ct.vmid, name: ct.name })),
      ];

      const remaining = await this.waitForShutdown(allIds, resolved, node, stopTimeout);

      if (remaining.length > 0 && forceStop) {
        logger.warn(`${remaining.length} VMs/CTs didn't shut down gracefully, force-stopping...`);
        for (const item of remaining) {
          try {
            if (resolved.mode === 'cli') {
              if (item.type === 'qemu') {
                await this.stopVMCli(resolved.qmPath, item.vmid);
              } else {
                await this.stopCTCli(resolved.pctPath, item.vmid);
              }
            } else {
              const host = this.config.proxmoxHost || PROXMOX.DEFAULT_HOST;
              const port = this.config.proxmoxPort || PROXMOX.DEFAULT_PORT;
              const insecure = this.config.proxmoxInsecure !== false;
              const baseUrl = `https://${host}:${port}${PROXMOX.API_BASE}`;
              const headers: Record<string, string> = {
                'Authorization': `PVEAPIToken=${this.config.proxmoxTokenId}=${this.config.proxmoxTokenSecret}`,
              };
              if (item.type === 'qemu') {
                await this.stopVMApi(baseUrl, node, item.vmid, headers, insecure);
              } else {
                await this.stopCTApi(baseUrl, node, item.vmid, headers, insecure);
              }
            }
            logger.dim(`  Force-stopped ${item.type} ${item.vmid} (${item.name || 'unnamed'})`);
          } catch (error) {
            logger.error(
              `  Failed to force-stop ${item.type} ${item.vmid}: ${
                error instanceof Error ? error.message : String(error)
              }`,
            );
          }
        }
      } else if (remaining.length > 0) {
        logger.warn(`${remaining.length} VMs/CTs still running (force-stop disabled)`);
      }

      logger.success('Proxmox shutdown sequence completed');
    } catch (error) {
      logger.error(
        `Proxmox action failed: ${error instanceof Error ? error.message : String(error)}`,
      );
    }
  }

  // ─── CLI-based methods ─────────────────────────────────────────────

  /**
   * Get list of running QEMU VMs via qm list
   */
  private async getRunningVMsCli(
    qmPath: string,
  ): Promise<Array<{ vmid: number; name: string }>> {
    try {
      const { stdout } = await execFileAsync(qmPath, ['list']);
      return this.parseQmList(stdout);
    } catch (error) {
      logger.error(
        `Failed to list VMs via CLI: ${error instanceof Error ? error.message : String(error)}`,
      );
      return [];
    }
  }

  /**
   * Get list of running LXC containers via pct list
   */
  private async getRunningCTsCli(
    pctPath: string,
  ): Promise<Array<{ vmid: number; name: string }>> {
    try {
      const { stdout } = await execFileAsync(pctPath, ['list']);
      return this.parsePctList(stdout);
    } catch (error) {
      logger.error(
        `Failed to list CTs via CLI: ${error instanceof Error ? error.message : String(error)}`,
      );
      return [];
    }
  }

  /**
   * Parse qm list output
   * Format: VMID NAME STATUS MEM(MB) BOOTDISK(GB) PID
   */
  private parseQmList(output: string): Array<{ vmid: number; name: string }> {
    const results: Array<{ vmid: number; name: string }> = [];
    const lines = output.trim().split('\n');

    // Skip header line
    for (let i = 1; i < lines.length; i++) {
      const match = lines[i].match(/^\s*(\d+)\s+(\S+)\s+(running|stopped|paused)/);
      if (match && match[3] === 'running') {
        results.push({ vmid: parseInt(match[1], 10), name: match[2] });
      }
    }
    return results;
  }

  /**
   * Parse pct list output
   * Format: VMID Status Lock Name
   */
  private parsePctList(output: string): Array<{ vmid: number; name: string }> {
    const results: Array<{ vmid: number; name: string }> = [];
    const lines = output.trim().split('\n');

    // Skip header line
    for (let i = 1; i < lines.length; i++) {
      const match = lines[i].match(/^\s*(\d+)\s+(running|stopped)\s+\S*\s*(.*)/);
      if (match && match[2] === 'running') {
        results.push({ vmid: parseInt(match[1], 10), name: match[3]?.trim() || '' });
      }
    }
    return results;
  }

  private async shutdownVMCli(qmPath: string, vmid: number): Promise<void> {
    await execFileAsync(qmPath, ['shutdown', String(vmid)]);
  }

  private async shutdownCTCli(pctPath: string, vmid: number): Promise<void> {
    await execFileAsync(pctPath, ['shutdown', String(vmid)]);
  }

  private async stopVMCli(qmPath: string, vmid: number): Promise<void> {
    await execFileAsync(qmPath, ['stop', String(vmid)]);
  }

  private async stopCTCli(pctPath: string, vmid: number): Promise<void> {
    await execFileAsync(pctPath, ['stop', String(vmid)]);
  }

  /**
   * Get VM/CT status via CLI
   * Returns the status string (e.g., 'running', 'stopped')
   */
  private async getStatusCli(
    toolPath: string,
    vmid: number,
  ): Promise<string> {
    const { stdout } = await execFileAsync(toolPath, ['status', String(vmid)]);
    // Output format: "status: running\n"
    const status = stdout.trim().split(':')[1]?.trim() || 'unknown';
    return status;
  }

  // ─── API-based methods ─────────────────────────────────────────────

  /**
   * Make an API request to the Proxmox server
   */
  private async apiRequest(
    url: string,
    method: string,
    headers: Record<string, string>,
    insecure: boolean,
  ): Promise<unknown> {
    const fetchOptions: RequestInit = {
      method,
      headers,
    };

    // Use NODE_TLS_REJECT_UNAUTHORIZED for insecure mode (self-signed certs)
    if (insecure) {
      // deno-lint-ignore no-explicit-any
      (globalThis as any).process?.env && ((globalThis as any).process.env.NODE_TLS_REJECT_UNAUTHORIZED = '0');
    }

    try {
      const response = await fetch(url, fetchOptions);

      if (!response.ok) {
        const body = await response.text();
        throw new Error(`Proxmox API error ${response.status}: ${body}`);
      }

      return await response.json();
    } finally {
      // Restore TLS verification
      if (insecure) {
        // deno-lint-ignore no-explicit-any
        (globalThis as any).process?.env && ((globalThis as any).process.env.NODE_TLS_REJECT_UNAUTHORIZED = '1');
      }
    }
  }

  /**
   * Get list of running QEMU VMs via API
   */
  private async getRunningVMsApi(
    baseUrl: string,
    node: string,
    headers: Record<string, string>,
    insecure: boolean,
  ): Promise<Array<{ vmid: number; name: string }>> {
    try {
      const response = await this.apiRequest(
        `${baseUrl}/nodes/${node}/qemu`,
        'GET',
        headers,
        insecure,
      ) as { data: Array<{ vmid: number; name: string; status: string }> };

      return (response.data || [])
        .filter((vm) => vm.status === 'running')
        .map((vm) => ({ vmid: vm.vmid, name: vm.name || '' }));
    } catch (error) {
      logger.error(
        `Failed to list VMs: ${error instanceof Error ? error.message : String(error)}`,
      );
      return [];
    }
  }

  /**
   * Get list of running LXC containers via API
   */
  private async getRunningCTsApi(
    baseUrl: string,
    node: string,
    headers: Record<string, string>,
    insecure: boolean,
  ): Promise<Array<{ vmid: number; name: string }>> {
    try {
      const response = await this.apiRequest(
        `${baseUrl}/nodes/${node}/lxc`,
        'GET',
        headers,
        insecure,
      ) as { data: Array<{ vmid: number; name: string; status: string }> };

      return (response.data || [])
        .filter((ct) => ct.status === 'running')
        .map((ct) => ({ vmid: ct.vmid, name: ct.name || '' }));
    } catch (error) {
      logger.error(
        `Failed to list CTs: ${error instanceof Error ? error.message : String(error)}`,
      );
      return [];
    }
  }

  private async shutdownVMApi(
    baseUrl: string,
    node: string,
    vmid: number,
    headers: Record<string, string>,
    insecure: boolean,
  ): Promise<void> {
    await this.apiRequest(
      `${baseUrl}/nodes/${node}/qemu/${vmid}/status/shutdown`,
      'POST',
      headers,
      insecure,
    );
  }

  private async shutdownCTApi(
    baseUrl: string,
    node: string,
    vmid: number,
    headers: Record<string, string>,
    insecure: boolean,
  ): Promise<void> {
    await this.apiRequest(
      `${baseUrl}/nodes/${node}/lxc/${vmid}/status/shutdown`,
      'POST',
      headers,
      insecure,
    );
  }

  private async stopVMApi(
    baseUrl: string,
    node: string,
    vmid: number,
    headers: Record<string, string>,
    insecure: boolean,
  ): Promise<void> {
    await this.apiRequest(
      `${baseUrl}/nodes/${node}/qemu/${vmid}/status/stop`,
      'POST',
      headers,
      insecure,
    );
  }

  private async stopCTApi(
    baseUrl: string,
    node: string,
    vmid: number,
    headers: Record<string, string>,
    insecure: boolean,
  ): Promise<void> {
    await this.apiRequest(
      `${baseUrl}/nodes/${node}/lxc/${vmid}/status/stop`,
      'POST',
      headers,
      insecure,
    );
  }

  // ─── Shared methods ────────────────────────────────────────────────

  /**
   * Wait for VMs/CTs to shut down, return any that are still running after timeout
   */
  private async waitForShutdown(
    items: Array<{ type: 'qemu' | 'lxc'; vmid: number; name: string }>,
    resolved: { mode: 'api' | 'cli'; qmPath?: string; pctPath?: string },
    node: string,
    timeout: number,
  ): Promise<Array<{ type: 'qemu' | 'lxc'; vmid: number; name: string }>> {
    const startTime = Date.now();
    let remaining = [...items];

    while (remaining.length > 0 && (Date.now() - startTime) < timeout) {
      // Wait before polling
      await new Promise((resolve) => setTimeout(resolve, PROXMOX.STATUS_POLL_INTERVAL_SECONDS * 1000));

      // Check which are still running
      const stillRunning: typeof remaining = [];

      for (const item of remaining) {
        try {
          let status: string;

          if (resolved.mode === 'cli') {
            const toolPath = item.type === 'qemu' ? resolved.qmPath! : resolved.pctPath!;
            status = await this.getStatusCli(toolPath, item.vmid);
          } else {
            const host = this.config.proxmoxHost || PROXMOX.DEFAULT_HOST;
            const port = this.config.proxmoxPort || PROXMOX.DEFAULT_PORT;
            const insecure = this.config.proxmoxInsecure !== false;
            const baseUrl = `https://${host}:${port}${PROXMOX.API_BASE}`;
            const headers: Record<string, string> = {
              'Authorization': `PVEAPIToken=${this.config.proxmoxTokenId}=${this.config.proxmoxTokenSecret}`,
            };
            const statusUrl = `${baseUrl}/nodes/${node}/${item.type}/${item.vmid}/status/current`;
            const response = await this.apiRequest(statusUrl, 'GET', headers, insecure) as {
              data: { status: string };
            };
            status = response.data?.status || 'unknown';
          }

          if (status === 'running') {
            stillRunning.push(item);
          } else {
            logger.dim(`  ${item.type} ${item.vmid} (${item.name}) stopped`);
          }
        } catch (_error) {
          // If we can't check status, assume it might still be running
          stillRunning.push(item);
        }
      }

      remaining = stillRunning;

      if (remaining.length > 0) {
        const elapsed = Math.round((Date.now() - startTime) / 1000);
        logger.dim(`  Waiting... ${remaining.length} still running (${elapsed}s elapsed)`);
      }
    }

    return remaining;
  }
}