#!/usr/bin/env node

function normalizeBaseUrl(value) {
  return String(value ?? '').trim().replace(/\/+$/, '');
}

function requireValue(name, value) {
  if (!value) throw new Error(`${name} requires a value`);
  return value;
}

export function parseMemoryV2AppCanaryArgs(argv = [], env = process.env) {
  const options = {
    baseUrl: normalizeBaseUrl(env.MEMORY_V2_APP_BASE_URL || 'http://127.0.0.1:8081'),
    requireEnabled: false,
    requireTargetHealthy: false,
    expectedBackend: null,
    expectedSelectedBackend: null,
    timeoutMs: Number(env.MEMORY_V2_APP_CANARY_TIMEOUT_MS || 8000),
    help: false,
  };

  for (let i = 0; i < argv.length; i += 1) {
    const arg = argv[i];
    if (arg === '--base-url') {
      options.baseUrl = normalizeBaseUrl(requireValue(arg, argv[++i]));
    } else if (arg === '--require-enabled') {
      options.requireEnabled = true;
    } else if (arg === '--require-target-healthy') {
      options.requireTargetHealthy = true;
    } else if (arg === '--expect-backend') {
      options.expectedBackend = requireValue(arg, argv[++i]);
    } else if (arg === '--expect-selected-backend') {
      options.expectedSelectedBackend = requireValue(arg, argv[++i]);
    } else if (arg === '--timeout-ms') {
      options.timeoutMs = Number(requireValue(arg, argv[++i]));
    } else if (arg === '-h' || arg === '--help') {
      options.help = true;
    } else {
      throw new Error(`Unknown argument: ${arg}`);
    }
  }

  if (!options.baseUrl) throw new Error('--base-url is required');
  if (!Number.isFinite(options.timeoutMs) || options.timeoutMs <= 0) {
    throw new Error('--timeout-ms must be a positive number');
  }
  return options;
}

function usage() {
  return `Usage:
  node scripts/check-memory-v2-app-canary.mjs [options]

Options:
  --base-url <url>                    Portal base URL. Defaults to MEMORY_V2_APP_BASE_URL or http://127.0.0.1:8081.
  --require-enabled                   Fail unless /api/runtime/status reports memory.enabled=true.
  --expect-backend <name>             Fail unless memory.backend equals this value.
  --expect-selected-backend <name>    Fail unless memory.selectedBackend equals this value.
  --require-target-healthy            Fail unless at least one runtime target is healthy.
  --timeout-ms <ms>                   Request timeout. Defaults to 8000.
`;
}

async function fetchJson(fetchImpl, url, timeoutMs) {
  const controller = new AbortController();
  const timer = setTimeout(() => controller.abort(), timeoutMs);
  try {
    const response = await fetchImpl(url, { signal: controller.signal });
    const text = await response.text();
    let json = null;
    try {
      json = text ? JSON.parse(text) : null;
    } catch {
      json = null;
    }
    return {
      ok: response.ok,
      status: response.status,
      text,
      json,
    };
  } finally {
    clearTimeout(timer);
  }
}

function check(name, ok, details = {}) {
  return { name, ok: Boolean(ok), ...details };
}

export async function runMemoryV2AppCanaryCli({
  argv = process.argv.slice(2),
  env = process.env,
  stdout = process.stdout,
  fetchImpl = globalThis.fetch,
} = {}) {
  const options = parseMemoryV2AppCanaryArgs(argv, env);
  if (options.help) {
    stdout.write(usage());
    return 0;
  }
  if (typeof fetchImpl !== 'function') {
    throw new Error('fetch is not available in this Node.js runtime');
  }

  const runtime = await fetchJson(fetchImpl, `${options.baseUrl}/api/runtime/status`, options.timeoutMs);
  const apiStatus = await fetchJson(fetchImpl, `${options.baseUrl}/api/status`, options.timeoutMs);
  const authStatus = await fetchJson(fetchImpl, `${options.baseUrl}/auth/status`, options.timeoutMs);

  const memory = runtime.json?.memory ?? null;
  const targets = Array.isArray(runtime.json?.targets) ? runtime.json.targets : [];
  const healthyTargets = targets.filter((target) => target?.healthy);
  const checks = [
    check('runtime_status_http_ok', runtime.ok, { status: runtime.status }),
    check('runtime_status_ok', runtime.json?.ok === true),
    check('memory_status_present', Boolean(memory)),
    check('api_status_http_ok', apiStatus.ok, { status: apiStatus.status }),
    check('auth_status_http_ok', authStatus.ok, { status: authStatus.status }),
  ];

  if (options.requireEnabled) {
    checks.push(check('memory_enabled', memory?.enabled === true, { actual: memory?.enabled ?? null }));
  }
  if (options.expectedBackend) {
    checks.push(check('memory_backend', memory?.backend === options.expectedBackend, {
      expected: options.expectedBackend,
      actual: memory?.backend ?? null,
    }));
  }
  if (options.expectedSelectedBackend) {
    checks.push(check('memory_selected_backend', memory?.selectedBackend === options.expectedSelectedBackend, {
      expected: options.expectedSelectedBackend,
      actual: memory?.selectedBackend ?? null,
    }));
  }
  if (options.requireTargetHealthy) {
    checks.push(check('runtime_target_healthy', healthyTargets.length > 0, {
      healthyTargets: healthyTargets.length,
      targets: targets.length,
    }));
  }

  const report = {
    ok: checks.every((item) => item.ok),
    baseUrl: options.baseUrl,
    summary: {
      memory: memory
        ? {
            enabled: memory.enabled,
            backend: memory.backend,
            selectedBackend: memory.selectedBackend,
            failOpen: memory.failOpen,
            vectorEnabled: memory.vectorEnabled,
          }
        : null,
      targets: {
        total: targets.length,
        healthy: healthyTargets.length,
      },
      apiStatus: {
        status: apiStatus.status,
        body: apiStatus.text.slice(0, 80),
      },
      authStatus: {
        status: authStatus.status,
        authenticated: authStatus.json?.authenticated ?? null,
        mode: authStatus.json?.mode ?? null,
      },
    },
    checks,
  };

  stdout.write(`${JSON.stringify(report, null, 2)}\n`);
  return report.ok ? 0 : 1;
}

if (import.meta.url === `file://${process.argv[1]}`) {
  runMemoryV2AppCanaryCli().then((code) => {
    process.exitCode = code;
  }).catch((err) => {
    console.error(err instanceof Error ? err.message : err);
    process.exitCode = 1;
  });
}