import React, { useEffect, useMemo, useState } from "react";
import { useTranslation } from "react-i18next";
import { toast } from "sonner";
import { Plus, Server, Check } from "lucide-react";
import { Button } from "@/components/ui/button";
import {
  Dialog,
  DialogContent,
  DialogHeader,
  DialogTitle,
} from "@/components/ui/dialog";
import { mcpApi, type AppType } from "@/lib/api";
import { McpServer } from "@/types";
import McpListItem from "./McpListItem";
import McpFormModal from "./McpFormModal";
import { ConfirmDialog } from "../ConfirmDialog";
import {
  extractErrorMessage,
  translateMcpBackendError,
} from "@/utils/errorUtils";

interface McpPanelProps {
  open: boolean;
  onOpenChange: (open: boolean) => void;
  appType: AppType;
}

/**
 * MCP 管理面板
 * 采用与主界面一致的设计风格，右上角添加按钮，每个 MCP 占一行
 */
const McpPanel: React.FC<McpPanelProps> = ({
  open,
  onOpenChange,
  appType,
}) => {
  const { t } = useTranslation();
  const [servers, setServers] = useState<Record<string, McpServer>>({});
  const [loading, setLoading] = useState(true);
  const [isFormOpen, setIsFormOpen] = useState(false);
  const [editingId, setEditingId] = useState<string | null>(null);
  const [confirmDialog, setConfirmDialog] = useState<{
    isOpen: boolean;
    title: string;
    message: string;
    onConfirm: () => void;
  } | null>(null);

  const reload = async () => {
    setLoading(true);
    try {
      const cfg = await mcpApi.getConfig(appType);
      setServers(cfg.servers || {});
    } finally {
      setLoading(false);
    }
  };

  useEffect(() => {
    const setup = async () => {
      try {
        // 初始化：仅从对应客户端导入已有 MCP，不做“预设落库”
        if (appType === "claude") {
          await mcpApi.importFromClaude();
        } else if (appType === "codex") {
          await mcpApi.importFromCodex();
        }
      } catch (e) {
        console.warn("MCP 初始化导入失败（忽略继续）", e);
      } finally {
        await reload();
      }
    };
    setup();
    // appType 改变时重新初始化
  }, [appType]);

  const handleToggle = async (id: string, enabled: boolean) => {
    // 乐观更新：立即更新 UI
    const previousServers = servers;
    setServers((prev) => ({
      ...prev,
      [id]: {
        ...prev[id],
        enabled,
      },
    }));

    try {
      // 后台调用 API
      await mcpApi.setEnabled(appType, id, enabled);
      toast.success(
        enabled ? t("mcp.msg.enabled") : t("mcp.msg.disabled"),
        { duration: 1500 },
      );
    } catch (e: any) {
      // 失败时回滚
      setServers(previousServers);
      const detail = extractErrorMessage(e);
      const mapped = translateMcpBackendError(detail, t);
      toast.error(
        mapped || detail || t("mcp.error.saveFailed"),
        { duration: mapped || detail ? 6000 : 5000 },
      );
    }
  };

  const handleEdit = (id: string) => {
    setEditingId(id);
    setIsFormOpen(true);
  };

  const handleAdd = () => {
    setEditingId(null);
    setIsFormOpen(true);
  };

  const handleDelete = (id: string) => {
    setConfirmDialog({
      isOpen: true,
      title: t("mcp.confirm.deleteTitle"),
      message: t("mcp.confirm.deleteMessage", { id }),
      onConfirm: async () => {
        try {
          await mcpApi.deleteServerInConfig(appType, id);
          await reload();
          setConfirmDialog(null);
          toast.success(t("mcp.msg.deleted"), { duration: 1500 });
        } catch (e: any) {
          const detail = extractErrorMessage(e);
          const mapped = translateMcpBackendError(detail, t);
          toast.error(
            mapped || detail || t("mcp.error.deleteFailed"),
            { duration: mapped || detail ? 6000 : 5000 },
          );
        }
      },
    });
  };

  const handleSave = async (
    id: string,
    server: McpServer,
    options?: { syncOtherSide?: boolean },
  ) => {
    try {
      const payload: McpServer = { ...server, id };
      await mcpApi.upsertServerInConfig(appType, id, payload, {
        syncOtherSide: options?.syncOtherSide,
      });
      await reload();
      setIsFormOpen(false);
      setEditingId(null);
      toast.success(t("mcp.msg.saved"), { duration: 1500 });
    } catch (e: any) {
      const detail = extractErrorMessage(e);
      const mapped = translateMcpBackendError(detail, t);
      toast.error(
        mapped || detail || t("mcp.error.saveFailed"),
        { duration: mapped || detail ? 6000 : 5000 },
      );
      // 继续抛出错误，让表单层可以给到直观反馈（避免被更高层遮挡）
      throw e;
    }
  };

  const handleCloseForm = () => {
    setIsFormOpen(false);
    setEditingId(null);
  };

  const serverEntries = useMemo(
    () => Object.entries(servers) as Array<[string, McpServer]>,
    [servers],
  );

  const enabledCount = useMemo(
    () => serverEntries.filter(([_, server]) => server.enabled).length,
    [serverEntries],
  );

  const panelTitle =
    appType === "claude" ? t("mcp.claudeTitle") : t("mcp.codexTitle");

  return (
    <>
      <Dialog open={open} onOpenChange={onOpenChange}>
        <DialogContent className="max-w-3xl max-h-[85vh] min-h-[600px] flex flex-col">
          <DialogHeader>
            <div className="flex items-center justify-between pr-8">
              <DialogTitle>{panelTitle}</DialogTitle>
              <Button type="button" variant="mcp" size="sm" onClick={handleAdd}>
                <Plus size={16} />
                {t("mcp.add")}
              </Button>
            </div>
          </DialogHeader>

          {/* Info Section */}
          <div className="flex-shrink-0 -mt-2">
            <div className="text-sm text-gray-500 dark:text-gray-400">
              {t("mcp.serverCount", { count: Object.keys(servers).length })} ·{" "}
              {t("mcp.enabledCount", { count: enabledCount })}
            </div>
          </div>

          {/* Content - Scrollable */}
          <div className="flex-1 overflow-y-auto -mx-6 px-6">
            {loading ? (
              <div className="text-center py-12 text-gray-500 dark:text-gray-400">
                {t("mcp.loading")}
              </div>
            ) : (
              (() => {
                const hasAny = serverEntries.length > 0;
                if (!hasAny) {
                  return (
                    <div className="text-center py-12">
                      <div className="w-16 h-16 mx-auto mb-4 bg-gray-100 dark:bg-gray-800 rounded-full flex items-center justify-center">
                        <Server
                          size={24}
                          className="text-gray-400 dark:text-gray-500"
                        />
                      </div>
                      <h3 className="text-lg font-medium text-gray-900 dark:text-gray-100 mb-2">
                        {t("mcp.empty")}
                      </h3>
                      <p className="text-gray-500 dark:text-gray-400 text-sm">
                        {t("mcp.emptyDescription")}
                      </p>
                    </div>
                  );
                }

                return (
                  <div className="space-y-3">
                    {/* 已安装 */}
                    {serverEntries.map(([id, server]) => (
                      <McpListItem
                        key={`installed-${id}`}
                        id={id}
                        server={server}
                        onToggle={handleToggle}
                        onEdit={handleEdit}
                        onDelete={handleDelete}
                      />
                    ))}

                    {/* 预设已移至"新增 MCP"面板中展示与套用 */}
                  </div>
                );
              })()
            )}
          </div>

          {/* Footer */}
          <div className="flex-shrink-0 flex items-center justify-end pt-4 border-t border-gray-200 dark:border-gray-800">
            <Button
              type="button"
              variant="mcp"
              size="sm"
              onClick={() => onOpenChange(false)}
            >
              <Check size={16} />
              {t("common.done")}
            </Button>
          </div>
        </DialogContent>
      </Dialog>

      {/* Form Modal */}
      {isFormOpen && (
        <McpFormModal
          appType={appType}
          editingId={editingId || undefined}
          initialData={editingId ? servers[editingId] : undefined}
          existingIds={Object.keys(servers)}
          onSave={handleSave}
          onClose={handleCloseForm}
        />
      )}

      {/* Confirm Dialog */}
      {confirmDialog && (
        <ConfirmDialog
          isOpen={confirmDialog.isOpen}
          title={confirmDialog.title}
          message={confirmDialog.message}
          onConfirm={confirmDialog.onConfirm}
          onCancel={() => setConfirmDialog(null)}
        />
      )}
    </>
  );
};

export default McpPanel;