import { useCallback, useEffect, useMemo, useState } from "react";
import { Loader2, Save } from "lucide-react";
import { toast } from "sonner";
import {
  Dialog,
  DialogContent,
  DialogFooter,
  DialogHeader,
  DialogTitle,
} from "@/components/ui/dialog";
import { Tabs, TabsContent, TabsList, TabsTrigger } from "@/components/ui/tabs";
import { Button } from "@/components/ui/button";
import { settingsApi } from "@/lib/api";
import { LanguageSettings } from "@/components/settings/LanguageSettings";
import { ThemeSettings } from "@/components/settings/ThemeSettings";
import { WindowSettings } from "@/components/settings/WindowSettings";
import { DirectorySettings } from "@/components/settings/DirectorySettings";
import { ImportExportSection } from "@/components/settings/ImportExportSection";
import { AboutSection } from "@/components/settings/AboutSection";
import { useSettings } from "@/hooks/useSettings";
import { useImportExport } from "@/hooks/useImportExport";
import { useTranslation } from "react-i18next";
import type { SettingsFormState } from "@/hooks/useSettings";

interface SettingsDialogProps {
  open: boolean;
  onOpenChange: (open: boolean) => void;
  onImportSuccess?: () => void | Promise<void>;
}

export function SettingsPage({
  open,
  onOpenChange,
  onImportSuccess,
}: SettingsDialogProps) {
  const { t } = useTranslation();
  const {
    settings,
    isLoading,
    isSaving,
    isPortable,
    appConfigDir,
    resolvedDirs,
    updateSettings,
    updateDirectory,
    updateAppConfigDir,
    browseDirectory,
    browseAppConfigDir,
    resetDirectory,
    resetAppConfigDir,
    saveSettings,
    autoSaveSettings,
    requiresRestart,
    acknowledgeRestart,
  } = useSettings();

  const {
    selectedFile,
    status: importStatus,
    errorMessage,
    backupId,
    isImporting,
    selectImportFile,
    importConfig,
    exportConfig,
    clearSelection,
    resetStatus,
  } = useImportExport({ onImportSuccess });

  const [activeTab, setActiveTab] = useState<string>("general");
  const [showRestartPrompt, setShowRestartPrompt] = useState(false);

  useEffect(() => {
    if (open) {
      setActiveTab("general");
      resetStatus();
    }
  }, [open, resetStatus]);

  useEffect(() => {
    if (requiresRestart) {
      setShowRestartPrompt(true);
    }
  }, [requiresRestart]);

  const closeAfterSave = useCallback(() => {
    // 保存成功后关闭：不再重置语言，避免需要“保存两次”才生效
    acknowledgeRestart();
    clearSelection();
    resetStatus();
    onOpenChange(false);
  }, [acknowledgeRestart, clearSelection, onOpenChange, resetStatus]);

  const handleSave = useCallback(async () => {
    try {
      const result = await saveSettings(undefined, { silent: false });
      if (!result) return;
      if (result.requiresRestart) {
        setShowRestartPrompt(true);
        return;
      }
      closeAfterSave();
    } catch (error) {
      console.error("[SettingsPage] Failed to save settings", error);
    }
  }, [closeAfterSave, saveSettings]);

  const handleRestartLater = useCallback(() => {
    setShowRestartPrompt(false);
    closeAfterSave();
  }, [closeAfterSave]);

  const handleRestartNow = useCallback(async () => {
    setShowRestartPrompt(false);
    if (import.meta.env.DEV) {
      toast.success(t("settings.devModeRestartHint"));
      closeAfterSave();
      return;
    }

    try {
      await settingsApi.restart();
    } catch (error) {
      console.error("[SettingsPage] Failed to restart app", error);
      toast.error(t("settings.restartFailed"));
    } finally {
      closeAfterSave();
    }
  }, [closeAfterSave, t]);

  // 通用设置即时保存（无需手动点击）
  // 使用 autoSaveSettings 避免误触发系统 API（开机自启、Claude 插件等）
  const handleAutoSave = useCallback(
    async (updates: Partial<SettingsFormState>) => {
      if (!settings) return;
      updateSettings(updates);
      try {
        await autoSaveSettings(updates);
      } catch (error) {
        console.error("[SettingsPage] Failed to autosave settings", error);
        toast.error(
          t("settings.saveFailedGeneric", {
            defaultValue: "保存失败，请重试",
          }),
        );
      }
    },
    [autoSaveSettings, settings, t, updateSettings],
  );

  const isBusy = useMemo(() => isLoading && !settings, [isLoading, settings]);

  return (
    <div className="mx-auto max-w-[56rem] flex flex-col h-[calc(100vh-8rem)] px-6">
      {isBusy ? (
        <div className="flex flex-1 items-center justify-center">
          <Loader2 className="h-8 w-8 animate-spin text-muted-foreground" />
        </div>
      ) : (
        <Tabs
          value={activeTab}
          onValueChange={setActiveTab}
          className="flex flex-col h-full"
        >
          <TabsList className="grid w-full grid-cols-3 mb-6 glass rounded-xl">
            <TabsTrigger value="general">
              {t("settings.tabGeneral")}
            </TabsTrigger>
            <TabsTrigger value="advanced">
              {t("settings.tabAdvanced")}
            </TabsTrigger>
            <TabsTrigger value="about">{t("common.about")}</TabsTrigger>
          </TabsList>

          <div className="flex-1 overflow-y-auto pr-2">
            <TabsContent value="general" className="space-y-6 mt-0">
              {settings ? (
                <>
                  <LanguageSettings
                    value={settings.language}
                    onChange={(lang) => handleAutoSave({ language: lang })}
                  />
                  <ThemeSettings />
                  <WindowSettings
                    settings={settings}
                    onChange={handleAutoSave}
                  />
                </>
              ) : null}
            </TabsContent>

            <TabsContent value="advanced" className="space-y-6 mt-0 pb-6">
              {settings ? (
                <>
                  <DirectorySettings
                    appConfigDir={appConfigDir}
                    resolvedDirs={resolvedDirs}
                    onAppConfigChange={updateAppConfigDir}
                    onBrowseAppConfig={browseAppConfigDir}
                    onResetAppConfig={resetAppConfigDir}
                    claudeDir={settings.claudeConfigDir}
                    codexDir={settings.codexConfigDir}
                    geminiDir={settings.geminiConfigDir}
                    onDirectoryChange={updateDirectory}
                    onBrowseDirectory={browseDirectory}
                    onResetDirectory={resetDirectory}
                  />
                  <ImportExportSection
                    status={importStatus}
                    selectedFile={selectedFile}
                    errorMessage={errorMessage}
                    backupId={backupId}
                    isImporting={isImporting}
                    onSelectFile={selectImportFile}
                    onImport={importConfig}
                    onExport={exportConfig}
                    onClear={clearSelection}
                  />
                  <div className="pt-6 border-t border-gray-200 dark:border-white/10">
                    <Button
                      onClick={handleSave}
                      className="w-full"
                      disabled={isSaving}
                    >
                      {isSaving ? (
                        <span className="inline-flex items-center gap-2">
                          <Loader2 className="h-4 w-4 animate-spin" />
                          {t("settings.saving")}
                        </span>
                      ) : (
                        <>
                          <Save className="mr-2 h-4 w-4" />
                          {t("common.save")}
                        </>
                      )}
                    </Button>
                  </div>
                </>
              ) : null}
            </TabsContent>

            <TabsContent value="about" className="mt-0">
              <AboutSection isPortable={isPortable} />
            </TabsContent>
          </div>
        </Tabs>
      )}

      <Dialog
        open={showRestartPrompt}
        onOpenChange={(open) => !open && handleRestartLater()}
      >
        <DialogContent
          zIndex="alert"
          className="max-w-md glass border-white/10"
        >
          <DialogHeader>
            <DialogTitle>{t("settings.restartRequired")}</DialogTitle>
          </DialogHeader>
          <div className="px-6">
            <p className="text-sm text-muted-foreground">
              {t("settings.restartRequiredMessage")}
            </p>
          </div>
          <DialogFooter>
            <Button
              variant="ghost"
              onClick={handleRestartLater}
              className="hover:bg-white/5"
            >
              {t("settings.restartLater")}
            </Button>
            <Button
              onClick={handleRestartNow}
              className="bg-primary hover:bg-primary/90"
            >
              {t("settings.restartNow")}
            </Button>
          </DialogFooter>
        </DialogContent>
      </Dialog>
    </div>
  );
}