"use client";

import { useEffect, useState } from "react";
import { Compass } from "lucide-react";
import { Button } from "@/components/ui/button";
import { Textarea } from "@/components/ui/textarea";
import { ZenCard } from "@/components/ui/zen-card";
import { ModeWorkspace } from "@/components/layout/mode-workspace";
import Result from "@/components/result";
import ResultAI from "@/components/result-ai";
import BaziChartDisplay from "@/components/modes/bazi-chart";
import LunarBirthPicker, {
  todaySolarYmd,
} from "@/components/shared/lunar-birth-picker";
import DateTimePicker, {
  nowDateString,
  nowTimeString,
} from "@/components/shared/datetime-picker";
import HexagramInput from "@/components/shared/hexagram-input";
import RegionSelect, {
  useRegionLocation,
} from "@/components/shared/region-select";
import { calculateBazi, type BaziChart } from "@/lib/calc/bazi";
import type { GuaResult } from "@/lib/calc/hexagram";
import { streamAiCompletion } from "@/lib/ai/client-stream";
import { saveHistoryEntry } from "@/lib/history/storage";

export default function CombinedForm() {
  const [birthDate, setBirthDate] = useState(todaySolarYmd());
  const [birthTime, setBirthTime] = useState("12:00");
  const [unknownHour, setUnknownHour] = useState(false);
  const [gender, setGender] = useState<"male" | "female">("male");
  const [birthProvince, setBirthProvince] = useState("");
  const [birthCity, setBirthCity] = useState("");
  const [currentProvince, setCurrentProvince] = useState("");
  const [currentCity, setCurrentCity] = useState("");
  const [calcDate, setCalcDate] = useState(nowDateString);
  const [calcTime, setCalcTime] = useState(nowTimeString);
  const [question, setQuestion] = useState("");
  const [withHexagram, setWithHexagram] = useState(false);
  const [castMode, setCastMode] = useState<"online" | "offline">("online");
  const [castActive, setCastActive] = useState(false);
  const [guaData, setGuaData] = useState<GuaResult | null>(null);

  const [chart, setChart] = useState<BaziChart | null>(null);
  const [completion, setCompletion] = useState("");
  const [error, setError] = useState("");
  const [isLoading, setIsLoading] = useState(false);

  const birthLocation = useRegionLocation(birthProvince, birthCity);
  const currentLocation = useRegionLocation(currentProvince, currentCity);
  const hexagramReady =
    !withHexagram ||
    (question.trim() !== "" && currentLocation !== null && guaData !== null);

  useEffect(() => {
    setCastActive(false);
    setGuaData(null);
  }, [currentProvince, currentCity, castMode, question, withHexagram]);

  function validate(): string | null {
    if (!birthLocation) {
      return "请选择出生地域";
    }
    if (!currentLocation) {
      return "请选择当前所在地域";
    }
    if (!question.trim()) {
      return "请输入问事内容";
    }
    if (withHexagram && !guaData) {
      return "请完成六爻起卦，或取消附加六爻";
    }
    return null;
  }

  function handlePreview() {
    const err = validate();
    if (err) {
      setError(err);
      return;
    }
    setError("");
    setChart(
      calculateBazi({
        date: birthDate,
        time: unknownHour ? "12:00" : birthTime,
        gender,
        longitude: birthLocation!.longitude,
        unknownHour,
      }),
    );
    setCompletion("");
  }

  async function handleAnalyze() {
    const err = validate();
    if (err) {
      setError(err);
      return;
    }
    if (!chart) {
      setChart(
        calculateBazi({
          date: birthDate,
          time: unknownHour ? "12:00" : birthTime,
          gender,
          longitude: birthLocation!.longitude,
          unknownHour,
        }),
      );
    }

    setError("");
    setCompletion("");
    setIsLoading(true);

    const activeChart =
      chart ??
      calculateBazi({
        date: birthDate,
        time: unknownHour ? "12:00" : birthTime,
        gender,
        longitude: birthLocation!.longitude,
        unknownHour,
      });

    try {
      const text = await streamAiCompletion(
        {
          mode: "combined",
          payload: {
            birth: {
              date: birthDate,
              time: unknownHour ? "12:00" : birthTime,
              gender,
              longitude: birthLocation!.longitude,
              unknownHour,
            },
            birthPlaceName: birthLocation!.name,
            currentPlaceName: currentLocation!.name,
            currentLongitude: currentLocation!.longitude,
            calcDate,
            calcTime,
            question,
            hexagram: withHexagram && guaData
              ? {
                  guaMark: guaData.result.guaMark,
                  guaTitle: guaData.result.guaTitle,
                  guaResult: guaData.result.guaResult,
                  guaChange: guaData.result.guaChange,
                }
              : undefined,
          },
        },
        setCompletion,
      );
      await saveHistoryEntry({
        mode: "combined",
        title: "综合测算解读",
        question,
        summary: activeChart.lunarDate,
        completion: text,
        baziInput: {
          date: birthDate,
          time: unknownHour ? "12:00" : birthTime,
          gender,
          longitude: birthLocation!.longitude,
          unknownHour,
          birthPlaceName: birthLocation!.name,
        },
        baziChart: activeChart,
        hexagram:
          withHexagram && guaData
            ? {
                guaMark: guaData.result.guaMark,
                guaTitle: guaData.result.guaTitle,
                guaResult: guaData.result.guaResult,
                guaChange: guaData.result.guaChange,
              }
            : undefined,
        meta: {
          出生地域: birthLocation!.name,
          当前地域: currentLocation!.name,
          测算时间: `${calcDate} ${calcTime}`,
          农历: activeChart.lunarDate,
          性别: gender === "male" ? "男" : "女",
          四柱: `${activeChart.pillars.year.ganZhi} ${activeChart.pillars.month.ganZhi} ${activeChart.pillars.day.ganZhi} ${activeChart.pillars.time.ganZhi}`,
          六爻: withHexagram && guaData ? guaData.result.guaTitle : "无",
        },
      });
    } catch (e) {
      setError(e instanceof Error ? e.message : String(e));
    } finally {
      setIsLoading(false);
    }
  }

  const downloadPreamble =
    completion && birthLocation && currentLocation
      ? `# 综合测算 AI 解读\n\n- 问事：${question}\n- 出生地域：${birthLocation.name}\n- 当前地域：${currentLocation.name}\n- 测算时间：${calcDate} ${calcTime}\n${chart ? `- 农历：${chart.lunarDate}\n` : ""}${withHexagram && guaData ? `- 六爻：${guaData.result.guaTitle}\n` : ""}`
      : undefined;

  return (
    <ModeWorkspace
      aiTitle="综合解读"
      aiPanel={
        <ResultAI
          panel
          completion={completion}
          isLoading={isLoading}
          onCompletion={handleAnalyze}
          error={error}
          emptyHint="填写完整信息后，点击「综合测算」"
          downloadFilename={completion ? "综合测算解读.md" : undefined}
          downloadPreamble={downloadPreamble}
        />
      }
    >
      <ZenCard title="人和 · 生辰" subtitle="出生时空与地域" className="flex h-full min-h-0 flex-col">
        <LunarBirthPicker
          label="出生日期 / 时间（农历）"
          solarDate={birthDate}
          time={birthTime}
          timeDisabled={unknownHour}
          onSolarDateChange={setBirthDate}
          onTimeChange={setBirthTime}
        />
        <label className="flex items-center gap-2 text-xs text-muted-foreground">
          <input
            type="checkbox"
            checked={unknownHour}
            onChange={(e) => setUnknownHour(e.target.checked)}
          />
          时辰不详
        </label>
        <div className="flex gap-4">
          {(["male", "female"] as const).map((g) => (
            <label key={g} className="flex items-center gap-2 text-sm">
              <input
                type="radio"
                name="combined-gender"
                checked={gender === g}
                onChange={() => setGender(g)}
              />
              {g === "male" ? "男" : "女"}
            </label>
          ))}
        </div>
        <RegionSelect
          label="出生地域"
          provinceCode={birthProvince}
          cityCode={birthCity}
          onProvinceChange={setBirthProvince}
          onCityChange={setBirthCity}
        />
      </ZenCard>

      <ZenCard title="天时地利 · 问事" subtitle="当前时空与所求" className="flex h-full min-h-0 flex-col">
        <RegionSelect
          label="当前所在地域"
          provinceCode={currentProvince}
          cityCode={currentCity}
          onProvinceChange={setCurrentProvince}
          onCityChange={setCurrentCity}
        />
        <DateTimePicker
          label="测算时刻"
          date={calcDate}
          time={calcTime}
          onDateChange={setCalcDate}
          onTimeChange={setCalcTime}
        />
        <Textarea
          placeholder="具体所求..."
          value={question}
          onChange={(e) => setQuestion(e.target.value)}
          rows={3}
          className="border-border/60 bg-background/50"
        />
        <label className="flex items-center gap-2 text-sm">
          <input
            type="checkbox"
            checked={withHexagram}
            onChange={(e) => {
              setWithHexagram(e.target.checked);
              setGuaData(null);
            }}
          />
          附加六爻（可选）
        </label>
        {withHexagram && (
          <div className="space-y-3 rounded-xl border border-border/50 bg-secondary/20 p-3">
            <div className="flex gap-2">
              <Button
                type="button"
                size="sm"
                variant={castMode === "online" ? "default" : "outline"}
                onClick={() => {
                  setCastMode("online");
                  setGuaData(null);
                }}
              >
                线上摇卦
              </Button>
              <Button
                type="button"
                size="sm"
                variant={castMode === "offline" ? "default" : "outline"}
                onClick={() => {
                  setCastMode("offline");
                  setGuaData(null);
                }}
              >
                线下录入
              </Button>
            </div>
            <HexagramInput
              key={castMode}
              mode={castMode}
              enabled={question.trim() !== "" && currentLocation !== null}
              active={castActive}
              onStart={() => setCastActive(true)}
              onResult={setGuaData}
              onClear={() => {
                setGuaData(null);
                setCastActive(false);
              }}
            />
            {guaData && (
              <div className="rounded-lg border bg-card p-3">
                <Result {...guaData.result} />
              </div>
            )}
          </div>
        )}
        {error && !completion && (
          <p className="text-sm text-destructive">{error}</p>
        )}
        <div className="flex gap-2">
          <Button variant="outline" onClick={handlePreview} className="flex-1">
            预览排盘
          </Button>
          <Button
            onClick={handleAnalyze}
            disabled={isLoading || (withHexagram && !hexagramReady)}
            className="flex-1"
          >
            <Compass size={16} className="mr-1" />
            综合测算
          </Button>
        </div>
        {chart && <BaziChartDisplay chart={chart} />}
      </ZenCard>
    </ModeWorkspace>
  );
}