/**
 * Module health check command
 *
 * Usage:
 *   celilo module health [module-id] [--json] [--debug]
 */

import { getDb } from '../../db/client';
import type { HealthCheckResult } from '../../services/health-runner';
import { runAllHealthChecks, runModuleHealthCheck } from '../../services/health-runner';
import { getArg, hasFlag } from '../parser';
import type { CommandResult } from '../types';

const STATUS_ICONS: Record<string, string> = {
  healthy: '●',
  degraded: '⚠',
  unhealthy: '✗',
  'no-checks': '—',
  error: '✗',
};

const CHECK_ICONS: Record<string, string> = {
  pass: '✓',
  warn: '⚠',
  fail: '✗',
  skip: '○',
};

export function formatResult(result: HealthCheckResult): string {
  const icon = STATUS_ICONS[result.status] || '?';
  const lines: string[] = [];

  if (result.status === 'no-checks') {
    lines.push(`  ${result.moduleId} ${icon} no health check defined`);
    // Annotate the waiver beside the verdict, never instead of it: the
    // module is still unmeasured, a human just decided it needs no check
    // (openspec/changes/health-waiver-mechanism, D3).
    if (result.waiver) {
      lines.push(
        `      waived: ${result.waiver.reason} (by ${result.waiver.by} at ${result.waiver.at})`,
      );
    }
    return lines.join('\n');
  }

  if (result.status === 'error') {
    lines.push(`  ${result.moduleId} ${icon} error: ${result.error}`);
    return lines.join('\n');
  }

  const stateNote =
    result.status === 'healthy' || result.status === 'degraded' ? ' → VERIFIED' : '';
  lines.push(`  ${result.moduleId} ${icon} ${result.status}${stateNote}`);

  for (const check of result.checks) {
    const checkIcon = CHECK_ICONS[check.status] || '?';
    lines.push(`    ${checkIcon} ${check.name.padEnd(20)} ${check.message}`);
    if (check.details) {
      lines.push(`      ${check.details}`);
    }
  }

  return lines.join('\n');
}

/**
 * Handle module health command
 */
export async function handleModuleHealth(
  args: string[],
  flags: Record<string, string | boolean>,
): Promise<CommandResult> {
  const db = getDb();
  const debug = hasFlag(flags, 'debug');
  const jsonOutput = hasFlag(flags, 'json');
  const moduleId = getArg(args, 0);

  let results: HealthCheckResult[];

  if (moduleId) {
    const result = await runModuleHealthCheck(moduleId, db, { debug, quiet: jsonOutput });
    results = [result];
  } else {
    results = await runAllHealthChecks(db, { debug, quiet: jsonOutput });
  }

  if (jsonOutput) {
    return {
      success: true,
      message: JSON.stringify({ modules: results }, null, 2),
      rawOutput: true,
    };
  }

  if (results.length === 0) {
    return {
      success: true,
      message: 'No deployed modules to check',
    };
  }

  const output = results.map(formatResult).join('\n\n');
  const allHealthy = results.every(
    (r) => r.status === 'healthy' || r.status === 'degraded' || r.status === 'no-checks',
  );

  if (!allHealthy) {
    return {
      success: false,
      error: output,
    };
  }

  return {
    success: true,
    message: output,
  };
}