import {
  DailyTrendResponseSchema,
  StrategyPerformanceResponseSchema,
  SubredditPerformanceResponseSchema,
  SuccessfulExamplesResponseSchema,
  FunnelResponseSchema,
  AiUsageSummaryResponseSchema,
} from '../../../../../packages/api-contracts/src/index.js';
import type { z } from 'zod';
import { createDashboardRequest } from '../../api/request.js';

type SubredditPerformanceResponse = z.infer<typeof SubredditPerformanceResponseSchema>;
type StrategyPerformanceResponse = z.infer<typeof StrategyPerformanceResponseSchema>;
type DailyTrendResponse = z.infer<typeof DailyTrendResponseSchema>;
type SuccessfulExamplesResponse = z.infer<typeof SuccessfulExamplesResponseSchema>;
type FunnelResponse = z.infer<typeof FunnelResponseSchema>;
type AiUsageSummaryResponse = z.infer<typeof AiUsageSummaryResponseSchema>;

async function parseResponse<T>(
  response: Response,
  schema: { parse(value: unknown): T },
): Promise<T> {
  const payload: unknown = await response.json();
  if (!response.ok) {
    const message =
      typeof payload === 'object' &&
      payload !== null &&
      'error' in payload &&
      typeof payload.error === 'string'
        ? payload.error
        : `Request failed (${response.status})`;
    throw new Error(message);
  }
  return schema.parse(payload);
}

export interface PerformanceApi {
  getSubredditPerformance(): Promise<SubredditPerformanceResponse>;
  getStrategyPerformance(): Promise<StrategyPerformanceResponse>;
  getDailyTrend(days: number): Promise<DailyTrendResponse>;
  getSuccessfulExamples(): Promise<SuccessfulExamplesResponse>;
  getFunnel(): Promise<FunnelResponse>;
  getAiUsage(days: number): Promise<AiUsageSummaryResponse>;
}

export function createPerformanceApi(
  fetchImplementation?: typeof fetch,
) {
  const request = createDashboardRequest(fetchImplementation);
  return {
    async getSubredditPerformance() {
      return parseResponse(
        await request('/api/analytics/by-subreddit'),
        SubredditPerformanceResponseSchema,
      );
    },
    async getStrategyPerformance() {
      return parseResponse(
        await request('/api/analytics/by-strategy'),
        StrategyPerformanceResponseSchema,
      );
    },
    async getDailyTrend(days: number) {
      return parseResponse(
        await request(`/api/analytics/trend?days=${days}`),
        DailyTrendResponseSchema,
      );
    },
    async getSuccessfulExamples() {
      return parseResponse(
        await request('/api/successful'),
        SuccessfulExamplesResponseSchema,
      );
    },
    async getFunnel() {
      return parseResponse(
        await request('/api/analytics/funnel'),
        FunnelResponseSchema,
      );
    },
    async getAiUsage(days: number) {
      return parseResponse(
        await request(`/api/analytics/ai-usage?days=${days}`),
        AiUsageSummaryResponseSchema,
      );
    },
  } satisfies PerformanceApi;
}

export const performanceApi = createPerformanceApi();