import { createServerFn } from "@tanstack/react-start";

export interface Question {
  id: number;
  question: string;
  answer: string;
  created_at: string;
  answered_at: string;
}

export interface QuestionStats {
  asked: number;
  answered: number;
}

const DEV_QUESTIONS: Question[] = [
  {
    id: 1,
    question: "What is a fact about octopuses?",
    answer: "An octopus has three hearts and blue blood.",
    created_at: "2026-03-23T18:10:00.000Z",
    answered_at: "2026-03-23T19:00:00.000Z",
  },
  {
    id: 2,
    question: "What is a fact about axolotls?",
    answer:
      "An axolotl can regrow limbs, parts of its heart, and even parts of its brain.",
    created_at: "2026-03-24T02:15:00.000Z",
    answered_at: "2026-03-24T05:45:00.000Z",
  },
  {
    id: 3,
    question: "What is a fact about crows?",
    answer: "Crows can recognize human faces and remember them for years.",
    created_at: "2026-03-25T08:30:00.000Z",
    answered_at: "2026-03-25T09:05:00.000Z",
  },
];

const DEV_QUESTION_STATS: QuestionStats = {
  asked: 16,
  answered: DEV_QUESTIONS.length,
};

function apiUrl(path: string) {
  const base = process.env.QA_API_BASE_URL ?? "http://127.0.0.1:3003";
  return new URL(path, base).toString();
}

export const getQuestions = createServerFn({ method: "GET" }).handler(
  async (): Promise<Question[]> => {
    if (process.env.NODE_ENV === "development") return DEV_QUESTIONS;

    try {
      const res = await fetch(apiUrl("/api/questions"));
      if (!res.ok) throw new Error("Failed to fetch questions");
      return (await res.json()) as Question[];
    } catch {
      return [];
    }
  },
);

export const getQuestionStats = createServerFn({ method: "GET" }).handler(
  async (): Promise<QuestionStats> => {
    if (process.env.NODE_ENV === "development") return DEV_QUESTION_STATS;

    try {
      const res = await fetch(apiUrl("/api/questions/stats"));
      if (!res.ok) throw new Error("Failed to fetch question stats");
      return (await res.json()) as QuestionStats;
    } catch {
      const questions = await getQuestions.__executeServer({
        method: "GET",
        data: undefined,
      });
      return {
        asked: (questions as Question[]).length,
        answered: (questions as Question[]).length,
      };
    }
  },
);

export const submitQuestion = createServerFn({ method: "POST" })
  .inputValidator((question: string) => question)
  .handler(async ({ data: question }): Promise<void> => {
    const res = await fetch(apiUrl("/api/questions"), {
      method: "POST",
      headers: { "Content-Type": "application/json" },
      body: JSON.stringify({ question }),
    });

    if (!res.ok) {
      if (res.status === 429) {
        throw new Error("Too many questions. Please try again later.");
      }
      throw new Error("Failed to submit question");
    }
  });