import { Play, RefreshCw, Save, Settings2 } from "lucide-react";
import {
  useCallback,
  useEffect,
  useState,
  type FormEvent,
  type ReactNode,
} from "react";
import { toast } from "sonner";
import { adminApi, ApiError } from "../../api/client";
import type {
  HintFeedGenerationStatus,
  HintFeedSettings,
  UpdateHintFeedSettingsRequest,
} from "../../api/types";
import {
  Badge,
  Button,
  Card,
  Input,
  LoadingState,
  Textarea,
} from "../../components/primitives";

interface HintAutoSectionProps {
  canEdit: boolean;
}

export function HintAutoSection({ canEdit }: HintAutoSectionProps) {
  const [settings, setSettings] = useState<HintFeedSettings>();
  const [status, setStatus] = useState<HintFeedGenerationStatus>();
  const [loading, setLoading] = useState(true);
  const [saving, setSaving] = useState(false);
  const [generating, setGenerating] = useState(false);

  const load = useCallback(async () => {
    setLoading(true);
    try {
      const [nextSettings, nextStatus] = await Promise.all([
        adminApi.hintFeedSettings(),
        adminApi.hintFeedStatus(),
      ]);
      setSettings(nextSettings);
      setStatus(nextStatus);
    } catch (error) {
      toast.error(message(error, "Hint 自动生成状态加载失败"));
    } finally {
      setLoading(false);
    }
  }, []);

  useEffect(() => {
    void load();
  }, [load]);

  async function save(event: FormEvent<HTMLFormElement>) {
    event.preventDefault();
    if (!settings) return;
    setSaving(true);
    try {
      const payload: UpdateHintFeedSettingsRequest = {
        generationIntervalHours: settings.generationIntervalHours,
        holidayCountriesZh: settings.holidayCountriesZh,
        holidayCountriesEn: settings.holidayCountriesEn,
        weatherCitiesZh: settings.weatherCitiesZh,
        weatherCitiesEn: settings.weatherCitiesEn,
        googleTrendsGeos: settings.googleTrendsGeos,
      };
      setSettings(await adminApi.updateHintFeedSettings(payload));
      setStatus(await adminApi.hintFeedStatus());
      toast.success("Hint 自动生成配置已保存");
    } catch (error) {
      toast.error(message(error, "Hint 自动生成配置保存失败"));
    } finally {
      setSaving(false);
    }
  }

  async function regenerate() {
    if (
      !window.confirm(
        "将立即抓取外部数据，并原子覆盖 zh/en 提示包。旧版本会保留到新一代全部生成成功。是否继续？",
      )
    ) {
      return;
    }
    setGenerating(true);
    try {
      const result = await adminApi.regenerateHintFeed();
      toast.success(
        `生成完成：zh ${result.zh.cardCount} 条，en ${result.en.cardCount} 条`,
      );
      await load();
    } catch (error) {
      toast.error(message(error, "Hint 提示包生成失败，旧版本仍保持可用"));
    } finally {
      setGenerating(false);
    }
  }

  if (loading || !settings || !status) {
    return <LoadingState label="加载 Hint 自动生成配置" />;
  }

  return (
    <section aria-labelledby="hint-auto-heading" className="space-y-4">
      <div className="flex flex-wrap items-end justify-between gap-3">
        <div>
          <h2 id="hint-auto-heading" className="text-xl font-bold">
            Hint 自动生成
          </h2>
          <p className="mt-1 text-sm text-muted">
            从 TopHub、Google Trends、Google News、节日和天气来源生成双语提示包。
            任一来源失败不会影响其他来源，整代生成失败时继续提供旧版本。
          </p>
        </div>
        <div className="flex flex-wrap gap-2">
          <Button variant="secondary" onClick={() => void load()}>
            <RefreshCw className="size-4" aria-hidden />
            刷新状态
          </Button>
          {canEdit ? (
            <Button loading={generating} onClick={() => void regenerate()}>
              <Play className="size-4" aria-hidden />
              立即生成
            </Button>
          ) : null}
        </div>
      </div>

      <div className="grid gap-4 md:grid-cols-2 xl:grid-cols-4">
        <StatusCard
          label="调度"
          value={settings.enabled ? `每 ${status.intervalHours} 小时` : "未启用"}
          tone={settings.enabled ? "success" : "neutral"}
        />
        <StatusCard
          label="上次结果"
          value={outcomeLabel(status.outcome)}
          detail={formatInstant(status.lastCompletedAt ?? status.lastStartedAt)}
          tone={outcomeTone(status.outcome)}
        />
        <StatusCard
          label="中文包"
          value={status.zhVersion ? `v${status.zhVersion}` : "未发布"}
          detail={
            status.zhCardCount === undefined ? undefined : `${status.zhCardCount} 条`
          }
          tone={status.zhVersion ? "success" : "warning"}
        />
        <StatusCard
          label="英文包"
          value={status.enVersion ? `v${status.enVersion}` : "未发布"}
          detail={
            status.enCardCount === undefined ? undefined : `${status.enCardCount} 条`
          }
          tone={status.enVersion ? "success" : "warning"}
        />
      </div>

      <Card className="p-5 sm:p-6">
        <form className="space-y-5" onSubmit={(event) => void save(event)}>
          <div className="flex items-center gap-2">
            <Settings2 className="size-4 text-primary" aria-hidden />
            <h3 className="font-semibold">生成设置</h3>
            <Badge className="ml-auto" tone={settings.topHubApiKeyConfigured ? "success" : "neutral"}>
              TopHub Key {settings.topHubApiKeyConfigured ? "已配置" : "未配置"}
            </Badge>
          </div>

          <div className="grid gap-4 md:grid-cols-3">
            <Field label="生成间隔（小时）">
              <Input
                type="number"
                min={1}
                max={168}
                value={settings.generationIntervalHours}
                readOnly={!canEdit}
                onChange={(event) =>
                  setSettings({
                    ...settings,
                    generationIntervalHours: Number(event.target.value),
                  })
                }
              />
            </Field>
            <Field label="中文节日国家">
              <Input
                value={settings.holidayCountriesZh}
                readOnly={!canEdit}
                onChange={(event) =>
                  setSettings({ ...settings, holidayCountriesZh: event.target.value })
                }
              />
            </Field>
            <Field label="英文节日国家">
              <Input
                value={settings.holidayCountriesEn}
                readOnly={!canEdit}
                onChange={(event) =>
                  setSettings({ ...settings, holidayCountriesEn: event.target.value })
                }
              />
            </Field>
          </div>

          <Field label="Google Trends 地区（逗号分隔）">
            <Input
              value={settings.googleTrendsGeos}
              readOnly={!canEdit}
              onChange={(event) =>
                setSettings({ ...settings, googleTrendsGeos: event.target.value })
              }
            />
          </Field>

          <div className="grid gap-4 lg:grid-cols-2">
            <Field label="中文天气城市（城市:纬度,经度;…）">
              <Textarea
                className="min-h-24 font-mono text-xs"
                value={settings.weatherCitiesZh}
                readOnly={!canEdit}
                onChange={(event) =>
                  setSettings({ ...settings, weatherCitiesZh: event.target.value })
                }
              />
            </Field>
            <Field label="英文天气城市（城市:纬度,经度;…）">
              <Textarea
                className="min-h-24 font-mono text-xs"
                value={settings.weatherCitiesEn}
                readOnly={!canEdit}
                onChange={(event) =>
                  setSettings({ ...settings, weatherCitiesEn: event.target.value })
                }
              />
            </Field>
          </div>

          <p className="text-xs text-muted">
            TopHub API Key 仅从服务器环境变量读取，不会保存到数据库或返回浏览器。
            手动 JSON 编辑与保存仍保留；下一次自动生成会更新双语版本。
          </p>

          {canEdit ? (
            <Button type="submit" loading={saving}>
              <Save className="size-4" aria-hidden />
              保存生成设置
            </Button>
          ) : null}
        </form>
      </Card>
    </section>
  );
}

function StatusCard({
  label,
  value,
  detail,
  tone,
}: {
  label: string;
  value: string;
  detail?: string;
  tone: "success" | "warning" | "danger" | "neutral" | "info" | "violet";
}) {
  return (
    <Card className="p-4">
      <p className="text-xs font-semibold uppercase tracking-wide text-muted">{label}</p>
      <div className="mt-2 flex items-center gap-2">
        <span className="font-semibold">{value}</span>
        <Badge tone={tone}>{detail ?? value}</Badge>
      </div>
    </Card>
  );
}

function Field({ label, children }: { label: string; children: ReactNode }) {
  return (
    <label className="block text-sm font-semibold">
      <span className="mb-2 block">{label}</span>
      {children}
    </label>
  );
}

function outcomeLabel(outcome: HintFeedGenerationStatus["outcome"]): string {
  return {
    IDLE: "尚未运行",
    RUNNING: "生成中",
    SUCCEEDED: "成功",
    FAILED: "失败",
  }[outcome];
}

function outcomeTone(
  outcome: HintFeedGenerationStatus["outcome"],
): "success" | "warning" | "danger" | "neutral" {
  return {
    IDLE: "neutral",
    RUNNING: "warning",
    SUCCEEDED: "success",
    FAILED: "danger",
  }[outcome] as "success" | "warning" | "danger" | "neutral";
}

function formatInstant(value?: string): string | undefined {
  if (!value) return undefined;
  const date = new Date(value);
  return Number.isNaN(date.getTime()) ? value : date.toLocaleString();
}

function message(error: unknown, fallback: string): string {
  return error instanceof ApiError ? error.message : fallback;
}