/**
 * Machine Remove Command
 * Remove a machine from the machine pool
 */

import { askConfirm, withInterviewSession } from '../../services/bus-interview';
import {
  getMachineByHostname,
  getMachineByIp,
  getModulesOnMachine,
  removeMachine,
} from '../../services/machine-pool';
import { celiloIntro, celiloOutro } from '../prompts';
import type { CommandResult } from '../types';

/**
 * Handle machine remove command
 *
 * @param args - Command arguments [hostname]
 * @param flags - Command flags (--force)
 */
export async function handleMachineRemove(
  args: string[],
  flags: Record<string, boolean | string> = {},
): Promise<CommandResult> {
  try {
    celiloIntro('Remove Machine');

    // Get identifier from args (hostname or IP)
    const identifier = args[0];
    if (!identifier) {
      return {
        success: false,
        error: 'Hostname or IP address is required\n\nUsage: celilo machine remove <hostname|ip>',
      };
    }

    // Look up by IP first, then by hostname
    const isIp = /^\d+\.\d+\.\d+\.\d+$/.test(identifier);
    const machine = isIp
      ? await getMachineByIp(identifier)
      : await getMachineByHostname(identifier);
    if (!machine) {
      return {
        success: false,
        error: `Machine not found: ${identifier}`,
      };
    }
    const hostname = machine.hostname;

    // Derived from the same source placement uses (celilo#773), so the two
    // cannot disagree. Previously this refused to remove an empty machine over
    // a module that no longer existed, and let an occupied one be removed.
    const occupants = getModulesOnMachine(machine.id);
    if (occupants.length > 0) {
      console.log(`\nError: Machine '${hostname}' has ${occupants.length} assigned module(s):`);
      for (const moduleId of occupants) {
        console.log(`  - ${moduleId}`);
      }
      console.log('\nModules must be unassigned or shut down before removing the machine.\n');

      return {
        success: false,
        error: 'Cannot remove machine with assigned modules',
      };
    }

    // Confirm deletion
    if (!flags.force) {
      const confirmed = await withInterviewSession(() =>
        askConfirm({
          scope: `machine:${hostname}`,
          key: 'remove',
          message: `Remove machine '${hostname}' (${machine.ipAddress})?`,
          defaultValue: false,
        }),
      );

      if (!confirmed) {
        return { success: false, error: 'Cancelled by user' };
      }
    }

    // Remove the machine
    await removeMachine(machine.id);

    celiloOutro(`Machine '${hostname}' removed successfully!`);

    return {
      success: true,
      message: `Removed machine: ${hostname}`,
    };
  } catch (error) {
    return {
      success: false,
      error: `Failed to remove machine: ${error instanceof Error ? error.message : String(error)}`,
    };
  }
}