'use client';

import { useForm } from 'react-hook-form';
import { IconButton, Button } from '@/components/ui/button';
import {
  Form,
  FormControl,
  FormField,
  FormItem,
  FormLabel,
  FormMessage,
} from '@/components/ui/form';
import { Input } from '@/components/ui/input';
import {
  Select,
  SelectContent,
  SelectItem,
  SelectTrigger,
  SelectValue,
} from '@/components/ui/select';
import GenderInput from '@/components/features/genderInput';
import { Gender } from '@/types/user';
import { useRouter } from 'next/navigation';
import { useCheckNickname, useCurrentUser, useUpdateUser } from '@/hooks/auth';
import { useEffect, useState } from 'react';
import { zodResolver } from '@hookform/resolvers/zod';
import * as z from 'zod';
import { calculateAge } from '@/lib/utils';
import dayjs from 'dayjs';
import ProfileLayout from '@/layout/ProfileLayout';

const schema = z
  .object({
    nickname: z
      .string()
      .trim()
      .min(1, 'Nickname is required')
      .min(2, 'Nickname must be between 2 and 20 characters'),
    gender: z.enum(Gender, { message: 'Please select a gender' }),
    year: z.string().min(1, 'Please select birth year'),
    month: z.string().min(1, 'Please select birth month'),
    day: z.string().min(1, 'Please select birth day'),
  })
  .refine(
    (data) => {
      const age = calculateAge(data.year, data.month, data.day);
      return age >= 18;
    },
    {
      message: 'Character age must be at least 18 years old',
      path: ['year'],
    }
  );

type EditProfileFormData = z.infer<typeof schema>;

const EditPage = () => {
  const router = useRouter();
  const { data: user, isLoading } = useCurrentUser();
  const { mutateAsync: updateUser } = useUpdateUser();
  const { mutateAsync: checkNickname } = useCheckNickname({
    onError: (error) => {
      form.setError('nickname', {
        message: error.errorMsg,
      });
    },
  });
  const [loading, setLoading] = useState(false);

  // 获取用户生日，如果是时间戳则转换为Date对象
  const getUserBirthday = () => {
    if (!user?.birthday) return null;

    return new Date(user.birthday);
  };

  const userBirthday = getUserBirthday();

  const form = useForm<EditProfileFormData>({
    resolver: zodResolver(schema),
    defaultValues: {
      nickname: user?.nickname || '',
      gender: user?.sex,
      year: userBirthday ? userBirthday.getFullYear().toString() : '',
      month: userBirthday ? (userBirthday.getMonth() + 1).toString().padStart(2, '0') : '',
      day: userBirthday ? userBirthday.getDate().toString().padStart(2, '0') : '',
    },
    mode: 'onChange',
  });

  const {
    formState: { isValid, isDirty },
  } = form;

  // 当用户数据加载完成后，更新表单值
  useEffect(() => {
    if (user && !isLoading) {
      const userBirthday = getUserBirthday();

      form.reset({
        nickname: user.nickname || '',
        gender: user.sex,
        year: userBirthday ? userBirthday.getFullYear().toString() : '',
        month: userBirthday ? (userBirthday.getMonth() + 1).toString().padStart(2, '0') : '',
        day: userBirthday ? userBirthday.getDate().toString().padStart(2, '0') : '',
      });
    }
  }, [user, isLoading, form]);

  const onSubmit = async (data: EditProfileFormData) => {
    if (!user?.userId) {
      return;
    }
    setLoading(true);
    try {
      const isExist = await checkNickname({
        nickname: data.nickname.trim(),
        exUserId: user.userId,
      });
      if (isExist) {
        form.setError('nickname', {
          message: 'This nickname is already taken',
        });
        return;
      }
      // 将日期字符串转换为时间戳
      const birthdayDate = new Date(`${data.year}-${data.month}-${data.day}`);
      const birthdayTimestamp = birthdayDate.getTime();

      await updateUser({
        nickname: data.nickname,
        birthday: birthdayTimestamp,
        userId: user.userId,
      });
      router.push('/profile');
    } catch (error) {
      console.error(error);
    } finally {
      setLoading(false);
    }
  };

  const handleBack = () => {
    router.back();
  };

  // 生成年份选项 (当前年份往前100年)
  const currentYear = new Date().getFullYear();
  const years = Array.from({ length: 100 }, (_, i) => currentYear - i).map((year) => ({
    value: year.toString(),
    label: year.toString(),
  }));

  const monthTexts = Array.from({ length: 12 }, (_, i) => dayjs().month(i).format('MMM'));
  // 生成月份选项
  const months = Array.from({ length: 12 }, (_, i) => ({
    value: (i + 1).toString().padStart(2, '0'),
    label: monthTexts[i],
  }));

  // 根据年份和月份计算该月的天数
  const getDaysInMonth = (year: string, month: string): number => {
    if (!year || !month) return 31; // 默认返回31天

    const yearNum = parseInt(year);
    const monthNum = parseInt(month);

    // 使用 Date 对象计算该月的实际天数
    // 传入下个月的第0天，会返回上个月的最后一天
    return new Date(yearNum, monthNum, 0).getDate();
  };

  // 监听年份和月份变化，动态生成日期选项
  const selectedYear = form.watch('year');
  const selectedMonth = form.watch('month');
  const selectedDay = form.watch('day');

  const daysInMonth = getDaysInMonth(selectedYear, selectedMonth);

  // 生成日期选项，根据选中的年月动态调整
  const days = Array.from({ length: daysInMonth }, (_, i) => ({
    value: (i + 1).toString().padStart(2, '0'),
    label: (i + 1).toString(),
  }));

  // 当年份或月份变化时，检查并调整日期
  useEffect(() => {
    if (selectedYear && selectedMonth && selectedDay) {
      const currentDay = parseInt(selectedDay);
      const maxDay = getDaysInMonth(selectedYear, selectedMonth);

      // 如果当前选中的日期超出了该月的最大天数，自动调整为该月最后一天
      if (currentDay > maxDay) {
        form.setValue('day', maxDay.toString().padStart(2, '0'), { shouldValidate: true });
      }
    }
  }, [selectedYear, selectedMonth, selectedDay, form]);

  return (
    <ProfileLayout title="Edit Profile">
      {/* 表单容器 */}
      <div className="bg-surface-base-normal rounded-2xl p-6">
        <Form {...form}>
          <form onSubmit={form.handleSubmit(onSubmit)} className="space-y-6">
            {/* 昵称字段 */}
            <FormField
              control={form.control}
              name="nickname"
              render={({ field }) => (
                <FormItem>
                  <FormLabel className="txt-label-m text-txt-primary-normal">Nickname</FormLabel>
                  <FormControl>
                    <Input
                      placeholder="Enter nickname"
                      maxLength={20}
                      showCount
                      error={!!form.formState.errors.nickname}
                      {...field}
                    />
                  </FormControl>
                  <FormMessage />
                </FormItem>
              )}
            />

            {/* 性别字段 */}
            <FormField
              control={form.control}
              name="gender"
              disabled={true}
              render={({ field }) => (
                <FormItem>
                  <FormLabel className="txt-label-m text-txt-primary-normal">Gender</FormLabel>
                  <FormControl>
                    <GenderInput
                      value={field.value as Gender}
                      onChange={field.onChange}
                      disabled={true}
                    />
                  </FormControl>
                  <p className="txt-body-s text-txt-secondary-normal">
                    Please note: gender cannot be changed after setting
                  </p>
                  <FormMessage />
                </FormItem>
              )}
            />

            {/* 年龄字段 */}
            <FormItem>
              <FormLabel className="txt-label-m text-txt-primary-normal">Age</FormLabel>
              <div className="grid grid-cols-3 gap-2">
                <FormField
                  control={form.control}
                  name="year"
                  render={({ field }) => (
                    <FormControl>
                      <Select value={field.value} onValueChange={field.onChange}>
                        <SelectTrigger block error={!!form.formState.errors.year}>
                          <SelectValue placeholder="Year" />
                        </SelectTrigger>
                        <SelectContent>
                          {years.map((year) => (
                            <SelectItem key={`${year.value}`} value={`${year.value}`}>
                              {year.label}
                            </SelectItem>
                          ))}
                        </SelectContent>
                      </Select>
                    </FormControl>
                  )}
                />

                <FormField
                  control={form.control}
                  name="month"
                  render={({ field }) => (
                    <FormControl>
                      <Select value={field.value} onValueChange={field.onChange}>
                        <SelectTrigger block error={!!form.formState.errors.year}>
                          <SelectValue placeholder="Month" />
                        </SelectTrigger>
                        <SelectContent>
                          {months.map((month) => (
                            <SelectItem key={month.value} value={month.value}>
                              {month.label}
                            </SelectItem>
                          ))}
                        </SelectContent>
                      </Select>
                    </FormControl>
                  )}
                />

                <FormField
                  control={form.control}
                  name="day"
                  render={({ field }) => (
                    <FormControl>
                      <Select value={field.value} onValueChange={field.onChange}>
                        <SelectTrigger block error={!!form.formState.errors.year}>
                          <SelectValue placeholder="Day" />
                        </SelectTrigger>
                        <SelectContent>
                          {days.map((day) => (
                            <SelectItem key={day.value} value={day.value}>
                              {day.label}
                            </SelectItem>
                          ))}
                        </SelectContent>
                      </Select>
                    </FormControl>
                  )}
                />
              </div>
              <FormMessage>
                {form.formState.errors.year?.message ||
                  form.formState.errors.month?.message ||
                  form.formState.errors.day?.message}
              </FormMessage>
            </FormItem>

            {/* 保存按钮 */}
            <div className="flex justify-end">
              <Button type="submit" size="large" disabled={!isValid || !isDirty} loading={loading}>
                Save
              </Button>
            </div>
          </form>
        </Form>
      </div>
    </ProfileLayout>
  );
};

export default EditPage;