import type { ApiErrorResponse, CheckFailure, CheckResult, HealthResponse, RuntimeMode } from "../shared/api";
import type { StoredCheckResult } from "./checker/types";
import type { Logger } from "./logger";

import { checkerRegistry } from "./checker/runner";
import { createNoopLogger } from "./logger";

export function createApiError(error: string, status: number): ApiErrorResponse {
  return { error, status };
}

export function createHeaders(mode: RuntimeMode, init: HeadersInit): Headers {
  const headers = new Headers(init);

  if (mode === "production") {
    headers.set("X-Content-Type-Options", "nosniff");
    headers.set("Referrer-Policy", "strict-origin-when-cross-origin");
  }

  return headers;
}

export function createHealthResponse(): HealthResponse {
  return {
    ok: true,
    service: "dial-server",
    timestamp: new Date().toISOString(),
  };
}

export function formatDuration(ms: number): string {
  if (ms >= 60000 && ms % 60000 === 0) return `${ms / 60000}m`;
  if (ms >= 1000 && ms % 1000 === 0) return `${ms / 1000}s`;
  return `${ms}ms`;
}

export function jsonResponse(
  body: unknown,
  options: { headers?: HeadersInit; mode: RuntimeMode; status?: number },
): Response {
  const headers = createHeaders(options.mode, {
    "Content-Type": "application/json; charset=utf-8",
    ...options.headers,
  });

  return new Response(JSON.stringify(body), {
    headers,
    status: options.status,
  });
}

export function mapCheckResult(row: StoredCheckResult, type: string, logger?: Logger): CheckResult {
  const log = logger ?? createNoopLogger();
  let failure: CheckFailure | null = null;
  if (row.failure) {
    try {
      failure = JSON.parse(row.failure) as CheckFailure;
    } catch {
      log.warn({ targetId: row.target_id, timestamp: row.timestamp }, "无法解析 failure 数据");
      failure = null;
    }
  }

  let observation: null | Record<string, unknown> = null;
  if (row.observation) {
    try {
      observation = JSON.parse(row.observation) as Record<string, unknown>;
    } catch {
      log.warn({ targetId: row.target_id, timestamp: row.timestamp }, "无法解析 observation 数据");
      observation = null;
    }
  }

  let detail: null | string = null;
  if (observation !== null) {
    try {
      const checker = checkerRegistry.get(type);
      detail = checker.buildDetail(observation);
    } catch {
      detail = null;
    }
  }

  return {
    detail,
    durationMs: row.duration_ms,
    failure,
    matched: row.matched === 1,
    observation,
    timestamp: row.timestamp,
  };
}