"use client";

import { useState, useEffect, useCallback } from "react";
import { useSession } from "next-auth/react";
import { useRouter } from "next/navigation";
import { Loader2 } from "lucide-react";
import { OnboardingProgress } from "./OnboardingProgress";
import { Step0HealthScore } from "./Step0HealthScore";
import { Step1BrandName } from "./Step1BrandName";
import { Step2Competitors } from "./Step2Competitors";
import { Step3Platforms } from "./Step3Platforms";
import { Step4HealthReport } from "./Step4HealthReport";
import { Step5ActionSuggestions } from "./Step5ActionSuggestions";
import { useOnboardingData } from "@/lib/hooks/use-onboarding-data";
import type { BrandHealthReport } from "@/types/onboarding";
import type { HealthScoreResponse } from "@/lib/api/health-score";

interface OnboardingState {
  currentStep: number;
  brandName: string;
  competitors: string[];
  platforms: string[];
  frequency: "daily" | "weekly" | "monthly";
  brandId: string | null;
  healthReport: BrandHealthReport | null;
  preCheckResult: HealthScoreResponse | null;
}

const initialState: OnboardingState = {
  currentStep: 0,
  brandName: "",
  competitors: [],
  platforms: [],
  frequency: "weekly",
  brandId: null,
  healthReport: null,
  preCheckResult: null,
};

export default function OnboardingPage() {
  const { status } = useSession();
  const router = useRouter();
  const [state, setState] = useState<OnboardingState>(initialState);

  const {
    isCompleted,
    isLoading: isStatusLoading,
    createBrand: hookCreateBrand,
    isCreatingBrand,
    mutationError,
  } = useOnboardingData();

  const error = mutationError?.message ?? null;

  useEffect(() => {
    if (isCompleted) {
      router.push("/dashboard");
    }
  }, [isCompleted, router]);

  const createBrand = useCallback(async () => {
    if (!state.brandName) return null;
    const brandId = await hookCreateBrand({
      name: state.brandName,
      competitors: state.competitors,
      platforms: state.platforms,
      frequency: state.frequency,
    });
    return brandId;
  }, [
    hookCreateBrand,
    state.brandName,
    state.competitors,
    state.platforms,
    state.frequency,
  ]);

  const handleStep0Next = (
    brandName: string,
    healthScore: HealthScoreResponse | null,
  ) => {
    setState((prev) => ({
      ...prev,
      brandName,
      preCheckResult: healthScore,
      currentStep: 1,
    }));
  };

  const handleStep1Next = (brandName: string) => {
    setState((prev) => ({
      ...prev,
      brandName,
      currentStep: 2,
    }));
  };

  const handleStep1Skip = () => {
    router.push("/dashboard");
  };

  const handleStep2Next = (competitors: string[]) => {
    setState((prev) => ({
      ...prev,
      competitors,
      currentStep: 3,
    }));
  };

  const handleStep2Back = () => {
    setState((prev) => ({
      ...prev,
      currentStep: 1,
    }));
  };

  const handleStep2Skip = async () => {
    setState((prev) => ({
      ...prev,
      competitors: [],
      currentStep: 3,
    }));
  };

  const handleStep3Next = async (
    platforms: string[],
    frequency: "daily" | "weekly" | "monthly",
  ) => {
    const brandId = await createBrand();
    if (brandId) {
      setState((prev) => ({
        ...prev,
        platforms,
        frequency,
        brandId,
        currentStep: 4,
      }));
    }
  };

  const handleStep3Back = () => {
    setState((prev) => ({
      ...prev,
      currentStep: 2,
    }));
  };

  const handleStep3Skip = async () => {
    const defaultPlatforms = [
      "wenxin",
      "kimi",
      "tongyi",
      "baidu_ai",
      "yuanbao",
      "qingyan",
      "doubao",
    ];
    const brandId = await createBrand();
    if (brandId) {
      setState((prev) => ({
        ...prev,
        platforms: defaultPlatforms,
        brandId,
        currentStep: 4,
      }));
    }
  };

  const handleStep4Next = (report: BrandHealthReport) => {
    setState((prev) => ({
      ...prev,
      healthReport: report,
      currentStep: 5,
    }));
  };

  const handleStep4Back = () => {
    setState((prev) => ({
      ...prev,
      currentStep: 3,
    }));
  };

  const handleStep5Complete = () => {
    router.push("/dashboard");
  };

  const handleStep5Back = () => {
    if (state.brandId) {
      setState((prev) => ({
        ...prev,
        currentStep: 4,
      }));
    }
  };

  const handleStep5Skip = () => {
    router.push("/dashboard");
  };

  if (status === "loading" || isStatusLoading) {
    return (
      <div className="flex min-h-screen items-center justify-center">
        <Loader2 className="h-8 w-8 animate-spin text-primary" />
      </div>
    );
  }

  if (status === "unauthenticated") {
    if (state.currentStep === 0) {
      // Step0 不需要登录
    } else {
      router.push("/login");
      return null;
    }
  }

  return (
    <div className="min-h-screen bg-gradient-to-b from-background to-muted/20 px-4 py-8">
      <div className="mx-auto max-w-4xl">
        <div className="mb-8 text-center">
          <h1 className="text-2xl font-bold">GEO 平台</h1>
          <p className="text-muted-foreground">新用户引导</p>
        </div>

        <div className="mb-8">
          <OnboardingProgress currentStep={state.currentStep} />
        </div>

        {error && (
          <div className="mb-4 rounded-lg bg-destructive/10 p-4 text-destructive text-center">
            {error}
          </div>
        )}

        {isCreatingBrand && (
          <div className="mb-4 rounded-lg bg-primary/10 p-4 text-center">
            <Loader2 className="mx-auto h-6 w-6 animate-spin text-primary" />
            <p className="mt-2 text-sm">正在创建品牌...</p>
          </div>
        )}

        <div className="mt-8">
          {state.currentStep === 0 && (
            <Step0HealthScore
              initialBrandName={state.brandName}
              onNext={handleStep0Next}
            />
          )}

          {state.currentStep === 1 && (
            <Step1BrandName
              initialValue={state.brandName}
              onNext={handleStep1Next}
              onSkip={handleStep1Skip}
            />
          )}

          {state.currentStep === 2 && (
            <Step2Competitors
              brandName={state.brandName}
              initialCompetitors={state.competitors}
              onNext={handleStep2Next}
              onBack={handleStep2Back}
              onSkip={handleStep2Skip}
            />
          )}

          {state.currentStep === 3 && (
            <Step3Platforms
              brandName={state.brandName}
              competitors={state.competitors}
              initialPlatforms={state.platforms}
              onNext={handleStep3Next}
              onBack={handleStep3Back}
              onSkip={handleStep3Skip}
            />
          )}

          {state.currentStep === 4 && state.brandId && (
            <Step4HealthReport
              brandId={state.brandId}
              brandName={state.brandName}
              competitors={state.competitors}
              platforms={state.platforms}
              onNext={handleStep4Next}
              onBack={handleStep4Back}
            />
          )}

          {state.currentStep === 5 && state.brandId && (
            <Step5ActionSuggestions
              brandId={state.brandId}
              brandName={state.brandName}
              onComplete={handleStep5Complete}
              onBack={handleStep5Back}
              onSkip={handleStep5Skip}
            />
          )}
        </div>
      </div>
    </div>
  );
}
