"use client";

import React, { useState, useEffect } from "react";
import {
  Dialog,
  DialogContent,
  DialogDescription,
  DialogFooter,
  DialogHeader,
  DialogTitle,
} from "@/components/ui/dialog";
import { Button } from "@/components/ui/button";
import { Input } from "@/components/ui/input";
import { Label } from "@/components/ui/label";
import { Textarea } from "@/components/ui/textarea";
import {
  Select,
  SelectContent,
  SelectItem,
  SelectTrigger,
  SelectValue,
} from "@/components/ui/select";
import { ScreenGroup, createScreenGroup, updateScreenGroup } from "@/lib/api/screenGroup";
import { toast } from "sonner";
import { apiClient } from "@/lib/api/client";
import {
  Command,
  CommandEmpty,
  CommandGroup,
  CommandInput,
  CommandItem,
  CommandList,
} from "@/components/ui/command";
import {
  Popover,
  PopoverContent,
  PopoverTrigger,
} from "@/components/ui/popover";
import { Check, ChevronsUpDown, Folder } from "lucide-react";
import { cn } from "@/lib/utils";

interface ScreenGroupModalProps {
  isOpen: boolean;
  onClose: () => void;
  onSuccess: () => void;
  group?: ScreenGroup | null; // 수정 모드일 때 기존 그룹 데이터
}

export function ScreenGroupModal({
  isOpen,
  onClose,
  onSuccess,
  group,
}: ScreenGroupModalProps) {
  const [currentCompanyCode, setCurrentCompanyCode] = useState<string>("");
  const [isSuperAdmin, setIsSuperAdmin] = useState(false);
  
  const [formData, setFormData] = useState({
    group_name: "",
    group_code: "",
    description: "",
    display_order: 0,
    target_company_code: "",
    parent_group_id: null as number | null,
  });
  const [loading, setLoading] = useState(false);
  const [companies, setCompanies] = useState<{ code: string; name: string }[]>([]);
  const [availableParentGroups, setAvailableParentGroups] = useState<ScreenGroup[]>([]);
  const [isParentGroupSelectOpen, setIsParentGroupSelectOpen] = useState(false);

  // 그룹 경로 가져오기 (계층 구조 표시용)
  const getGroupPath = (groupId: number): string => {
    const grp = availableParentGroups.find((g) => g.id === groupId);
    if (!grp) return "";
    
    const path: string[] = [grp.group_name];
    let currentGroup = grp;
    
    while ((currentGroup as any).parent_group_id) {
      const parent = availableParentGroups.find((g) => g.id === (currentGroup as any).parent_group_id);
      if (parent) {
        path.unshift(parent.group_name);
        currentGroup = parent;
      } else {
        break;
      }
    }
    
    return path.join(" > ");
  };

  // 그룹을 계층 구조로 정렬
  const getSortedGroups = (): typeof availableParentGroups => {
    const result: typeof availableParentGroups = [];
    
    const addChildren = (parentId: number | null, level: number) => {
      const children = availableParentGroups
        .filter((g) => (g as any).parent_group_id === parentId)
        .sort((a, b) => (a.display_order || 0) - (b.display_order || 0));
      
      for (const child of children) {
        result.push({ ...child, group_level: level } as any);
        addChildren(child.id, level + 1);
      }
    };
    
    addChildren(null, 1);
    return result;
  };

  // 현재 사용자 정보 로드
  useEffect(() => {
    const loadUserInfo = async () => {
      try {
        const response = await apiClient.get("/auth/me");
        const result = response.data;
        if (result.success && result.data) {
          const companyCode = result.data.companyCode || result.data.company_code || "";
          setCurrentCompanyCode(companyCode);
          setIsSuperAdmin(companyCode === "*");
        }
      } catch (error) {
        console.error("사용자 정보 로드 실패:", error);
      }
    };
    
    if (isOpen) {
      loadUserInfo();
    }
  }, [isOpen]);

  // 회사 목록 로드 (최고 관리자만)
  useEffect(() => {
    if (isSuperAdmin && isOpen) {
      const loadCompanies = async () => {
        try {
          const response = await apiClient.get("/admin/companies");
          const result = response.data;
          if (result.success && result.data) {
            const companyList = result.data.map((c: any) => ({
              code: c.company_code,
              name: c.company_name,
            }));
            setCompanies(companyList);
          }
        } catch (error) {
          console.error("회사 목록 로드 실패:", error);
        }
      };
      loadCompanies();
    }
  }, [isSuperAdmin, isOpen]);

  // 부모 그룹 목록 로드 (현재 회사의 대분류/중분류 그룹만)
  useEffect(() => {
    if (isOpen && currentCompanyCode) {
      const loadParentGroups = async () => {
        try {
          const response = await apiClient.get(`/screen-groups/groups?size=1000`);
          const result = response.data;
          if (result.success && result.data) {
            // 모든 그룹을 상위 그룹으로 선택 가능 (무한 중첩 지원)
            setAvailableParentGroups(result.data);
          }
        } catch (error) {
          console.error("부모 그룹 목록 로드 실패:", error);
        }
      };
      loadParentGroups();
    }
  }, [isOpen, currentCompanyCode]);

  // 그룹 데이터가 변경되면 폼 초기화
  useEffect(() => {
    if (currentCompanyCode) {
      if (group) {
        setFormData({
          group_name: group.group_name || "",
          group_code: group.group_code || "",
          description: group.description || "",
          display_order: group.display_order || 0,
          target_company_code: group.company_code || currentCompanyCode,
          parent_group_id: (group as any).parent_group_id || null,
        });
      } else {
        setFormData({
          group_name: "",
          group_code: "",
          description: "",
          display_order: 0,
          target_company_code: currentCompanyCode,
          parent_group_id: null,
        });
      }
    }
  }, [group, isOpen, currentCompanyCode]);

  const handleSubmit = async () => {
    // 필수 필드 검증
    if (!formData.group_name.trim()) {
      toast.error("그룹명을 입력하세요");
      return;
    }
    if (!formData.group_code.trim()) {
      toast.error("그룹 코드를 입력하세요");
      return;
    }

    setLoading(true);
    try {
      let response;
      if (group) {
        // 수정 모드
        response = await updateScreenGroup(group.id, formData);
      } else {
        // 추가 모드
        response = await createScreenGroup({
          ...formData,
          is_active: "Y",
        });
      }

      if (response.success) {
        toast.success(group ? "그룹이 수정되었습니다" : "그룹이 추가되었습니다");
        onSuccess();
        onClose();
      } else {
        toast.error(response.message || "작업에 실패했습니다");
      }
    } catch (error: any) {
      console.error("그룹 저장 실패:", error);
      toast.error("그룹 저장에 실패했습니다");
    } finally {
      setLoading(false);
    }
  };

  return (
    <Dialog open={isOpen} onOpenChange={onClose}>
      <DialogContent className="max-w-[95vw] sm:max-w-[500px]">
        <DialogHeader>
          <DialogTitle className="text-base sm:text-lg">
            {group ? "그룹 수정" : "그룹 추가"}
          </DialogTitle>
          <DialogDescription className="text-xs sm:text-sm">
            화면 그룹 정보를 입력하세요
          </DialogDescription>
        </DialogHeader>

        <div className="space-y-3 sm:space-y-4">
          {/* 회사 선택 (최고 관리자만) */}
          {isSuperAdmin && (
            <div>
              <Label htmlFor="target_company_code" className="text-xs sm:text-sm">
                회사 선택 *
              </Label>
              <Select
                value={formData.target_company_code}
                onValueChange={(value) =>
                  setFormData({ ...formData, target_company_code: value })
                }
              >
                <SelectTrigger className="h-8 text-xs sm:h-10 sm:text-sm">
                  <SelectValue placeholder="회사를 선택하세요" />
                </SelectTrigger>
                <SelectContent>
                  {companies.map((company) => (
                    <SelectItem key={company.code} value={company.code}>
                      {company.name} ({company.code})
                    </SelectItem>
                  ))}
                </SelectContent>
              </Select>
              <p className="text-muted-foreground mt-1 text-[10px] sm:text-xs">
                선택한 회사에 그룹이 생성됩니다
              </p>
            </div>
          )}

          {/* 부모 그룹 선택 (하위 그룹 만들기) - 트리 구조 + 검색 */}
          <div>
            <Label htmlFor="parent_group_id" className="text-xs sm:text-sm">
              상위 그룹 (선택사항)
            </Label>
            <Popover open={isParentGroupSelectOpen} onOpenChange={setIsParentGroupSelectOpen}>
              <PopoverTrigger asChild>
                <Button
                  variant="outline"
                  role="combobox"
                  aria-expanded={isParentGroupSelectOpen}
                  className="h-8 w-full justify-between text-xs sm:h-10 sm:text-sm"
                >
                  {formData.parent_group_id === null
                    ? "대분류로 생성"
                    : getGroupPath(formData.parent_group_id) || "그룹 선택"}
                  <ChevronsUpDown className="ml-2 h-4 w-4 shrink-0 opacity-50" />
                </Button>
              </PopoverTrigger>
              <PopoverContent
                className="p-0"
                style={{ width: "var(--radix-popover-trigger-width)" }}
                align="start"
              >
                <Command>
                  <CommandInput
                    placeholder="그룹 검색..."
                    className="text-xs sm:text-sm"
                  />
                  <CommandList>
                    <CommandEmpty className="text-xs sm:text-sm py-2 text-center">
                      그룹을 찾을 수 없습니다
                    </CommandEmpty>
                    <CommandGroup>
                      {/* 대분류로 생성 옵션 */}
                      <CommandItem
                        value="none"
                        onSelect={() => {
                          setFormData({ 
                            ...formData, 
                            parent_group_id: null,
                            // 대분류 선택 시 현재 회사 코드 유지
                          });
                          setIsParentGroupSelectOpen(false);
                        }}
                        className="text-xs sm:text-sm"
                      >
                        <Check
                          className={cn(
                            "mr-2 h-4 w-4",
                            formData.parent_group_id === null ? "opacity-100" : "opacity-0"
                          )}
                        />
                        <Folder className="mr-2 h-4 w-4 text-muted-foreground" />
                        대분류로 생성
                      </CommandItem>
                      {/* 계층 구조로 그룹 표시 */}
                      {getSortedGroups().map((parentGroup) => (
                        <CommandItem
                          key={parentGroup.id}
                          value={`${parentGroup.group_name} ${getGroupPath(parentGroup.id)}`}
                          onSelect={() => {
                            // 상위 그룹의 company_code로 자동 설정
                            const parentCompanyCode = parentGroup.company_code || formData.target_company_code;
                            setFormData({ 
                              ...formData, 
                              parent_group_id: parentGroup.id,
                              target_company_code: parentCompanyCode,
                            });
                            setIsParentGroupSelectOpen(false);
                          }}
                          className="text-xs sm:text-sm"
                        >
                          <Check
                            className={cn(
                              "mr-2 h-4 w-4",
                              formData.parent_group_id === parentGroup.id ? "opacity-100" : "opacity-0"
                            )}
                          />
                          {/* 들여쓰기로 계층 표시 */}
                          <span
                            style={{ marginLeft: `${(((parentGroup as any).group_level || 1) - 1) * 16}px` }}
                            className="flex items-center"
                          >
                            <Folder className="mr-2 h-4 w-4 text-muted-foreground" />
                            {parentGroup.group_name}
                          </span>
                        </CommandItem>
                      ))}
                    </CommandGroup>
                  </CommandList>
                </Command>
              </PopoverContent>
            </Popover>
            <p className="text-muted-foreground mt-1 text-[10px] sm:text-xs">
              부모 그룹을 선택하면 하위 그룹으로 생성됩니다
            </p>
          </div>

          {/* 그룹명 */}
          <div>
            <Label htmlFor="group_name" className="text-xs sm:text-sm">
              그룹명 *
            </Label>
            <Input
              id="group_name"
              value={formData.group_name}
              onChange={(e) =>
                setFormData({ ...formData, group_name: e.target.value })
              }
              placeholder="그룹명을 입력하세요"
              className="h-8 text-xs sm:h-10 sm:text-sm"
            />
          </div>

          {/* 그룹 코드 */}
          <div>
            <Label htmlFor="group_code" className="text-xs sm:text-sm">
              그룹 코드 *
            </Label>
            <Input
              id="group_code"
              value={formData.group_code}
              onChange={(e) =>
                setFormData({ ...formData, group_code: e.target.value })
              }
              placeholder="영문 대문자와 언더스코어로 입력"
              className="h-8 text-xs sm:h-10 sm:text-sm"
              disabled={!!group} // 수정 모드일 때는 코드 변경 불가
            />
            {group && (
              <p className="text-muted-foreground mt-1 text-[10px] sm:text-xs">
                그룹 코드는 수정할 수 없습니다
              </p>
            )}
          </div>

          {/* 설명 */}
          <div>
            <Label htmlFor="description" className="text-xs sm:text-sm">
              설명
            </Label>
            <Textarea
              id="description"
              value={formData.description}
              onChange={(e) =>
                setFormData({ ...formData, description: e.target.value })
              }
              placeholder="그룹에 대한 설명을 입력하세요"
              className="min-h-[60px] text-xs sm:min-h-[80px] sm:text-sm"
            />
          </div>

          {/* 정렬 순서 */}
          <div>
            <Label htmlFor="display_order" className="text-xs sm:text-sm">
              정렬 순서
            </Label>
            <Input
              id="display_order"
              type="number"
              value={formData.display_order}
              onChange={(e) =>
                setFormData({
                  ...formData,
                  display_order: parseInt(e.target.value) || 0,
                })
              }
              className="h-8 text-xs sm:h-10 sm:text-sm"
            />
            <p className="text-muted-foreground mt-1 text-[10px] sm:text-xs">
              숫자가 작을수록 상단에 표시됩니다
            </p>
          </div>
        </div>

        <DialogFooter className="gap-2 sm:gap-0">
          <Button
            variant="outline"
            onClick={onClose}
            disabled={loading}
            className="h-8 flex-1 text-xs sm:h-10 sm:flex-none sm:text-sm"
          >
            취소
          </Button>
          <Button
            onClick={handleSubmit}
            disabled={loading}
            className="h-8 flex-1 text-xs sm:h-10 sm:flex-none sm:text-sm"
          >
            {loading ? "저장 중..." : "저장"}
          </Button>
        </DialogFooter>
      </DialogContent>
    </Dialog>
  );
}