'use client';

import { zodResolver } from '@hookform/resolvers/zod';
import { useMutation, useQueryClient } from '@tanstack/react-query';
import Link from 'next/link';
import { useRouter } from 'next/navigation';
import * as React from 'react';
import { useForm } from 'react-hook-form';
import { z } from 'zod';
import { Button } from '@/components/ui/button';
import { Card, CardContent, CardHeader, CardTitle } from '@/components/ui/card';
import { Input } from '@/components/ui/input';
import { Label } from '@/components/ui/label';
import { Select } from '@/components/ui/select';
import { Textarea } from '@/components/ui/textarea';
import {
  industrialApi,
  PARK_STATUS_LABELS,
  REGION_LABELS,
  type CreateIndustrialParkPayload,
  type IndustrialParkStatus,
  type VietnamRegion,
} from '@/lib/khu-cong-nghiep-api';

const STATUS_OPTIONS: IndustrialParkStatus[] = [
  'PLANNING',
  'UNDER_CONSTRUCTION',
  'OPERATIONAL',
  'FULL',
];
const REGION_OPTIONS: VietnamRegion[] = ['NORTH', 'CENTRAL', 'SOUTH'];

const optionalString = z
  .string()
  .optional()
  .transform((v) => (v && v.trim() !== '' ? v.trim() : undefined));

const requiredString = (msg: string) => z.string().min(1, msg);

const nonNegativeNumber = (msg: string) =>
  z
    .string()
    .min(1, msg)
    .refine((v) => !isNaN(Number(v)) && Number(v) >= 0, 'Phải là số không âm');

const optionalNonNegativeNumber = z
  .string()
  .optional()
  .refine(
    (v) => v === undefined || v === '' || (!isNaN(Number(v)) && Number(v) >= 0),
    'Phải là số không âm',
  );

const parkFormSchema = z.object({
  name: requiredString('Vui lòng nhập tên KCN'),
  nameEn: optionalString,
  slug: requiredString('Vui lòng nhập slug'),
  developer: requiredString('Vui lòng nhập chủ đầu tư'),
  operator: optionalString,
  status: z.enum(['PLANNING', 'UNDER_CONSTRUCTION', 'OPERATIONAL', 'FULL']),

  address: requiredString('Vui lòng nhập địa chỉ'),
  district: requiredString('Vui lòng nhập quận/huyện'),
  province: requiredString('Vui lòng nhập tỉnh/thành'),
  region: z.enum(['NORTH', 'CENTRAL', 'SOUTH']),
  latitude: z
    .string()
    .min(1, 'Vui lòng nhập vĩ độ')
    .refine((v) => !isNaN(Number(v)) && Number(v) >= -90 && Number(v) <= 90, 'Vĩ độ từ -90 đến 90'),
  longitude: z
    .string()
    .min(1, 'Vui lòng nhập kinh độ')
    .refine(
      (v) => !isNaN(Number(v)) && Number(v) >= -180 && Number(v) <= 180,
      'Kinh độ từ -180 đến 180',
    ),

  totalAreaHa: nonNegativeNumber('Vui lòng nhập tổng diện tích'),
  leasableAreaHa: nonNegativeNumber('Vui lòng nhập diện tích cho thuê'),

  landRentUsdM2Year: optionalNonNegativeNumber,
  rbfRentUsdM2Month: optionalNonNegativeNumber,
  rbwRentUsdM2Month: optionalNonNegativeNumber,
  managementFeeUsd: optionalNonNegativeNumber,

  targetIndustries: optionalString,
  infrastructure: optionalString,

  establishedYear: optionalNonNegativeNumber,
  tenantCount: optionalNonNegativeNumber,

  description: optionalString,
  descriptionEn: optionalString,
});

type ParkFormValues = z.input<typeof parkFormSchema>;

function parseInfrastructure(text: string | undefined): Record<string, unknown> | undefined {
  if (!text) return undefined;
  const lines = text.split('\n').map((l) => l.trim()).filter(Boolean);
  if (lines.length === 0) return undefined;
  const out: Record<string, unknown> = {};
  for (const line of lines) {
    const idx = line.indexOf(':');
    if (idx > 0) {
      const key = line.slice(0, idx).trim();
      const value = line.slice(idx + 1).trim();
      if (key) out[key] = value;
    } else {
      out[line] = true;
    }
  }
  return Object.keys(out).length > 0 ? out : undefined;
}

function toNumOrUndef(v: string | undefined): number | undefined {
  if (v === undefined || v === '') return undefined;
  const n = Number(v);
  return isNaN(n) ? undefined : n;
}

export default function CreateIndustrialParkPage() {
  const router = useRouter();
  const queryClient = useQueryClient();
  const [error, setError] = React.useState<string | null>(null);

  const {
    register,
    handleSubmit,
    formState: { errors },
  } = useForm<ParkFormValues>({
    resolver: zodResolver(parkFormSchema),
    mode: 'onTouched',
    defaultValues: {
      status: 'PLANNING',
      region: 'NORTH',
    },
  });

  const mutation = useMutation({
    mutationFn: (payload: CreateIndustrialParkPayload) => industrialApi.createPark(payload),
    onSuccess: () => {
      queryClient.invalidateQueries({ queryKey: ['admin-industrial-parks'] });
      router.push('/industrial-parks');
    },
    onError: (err: unknown) => {
      setError(err instanceof Error ? err.message : 'Có lỗi xảy ra');
    },
  });

  const onSubmit = (data: ParkFormValues) => {
    setError(null);

    const totalArea = Number(data.totalAreaHa);
    const leasableArea = Number(data.leasableAreaHa);

    const industries = data.targetIndustries
      ? data.targetIndustries
          .split(',')
          .map((s) => s.trim())
          .filter(Boolean)
      : [];

    const payload: CreateIndustrialParkPayload = {
      name: data.name!,
      slug: data.slug!,
      developer: data.developer!,
      status: data.status,
      address: data.address!,
      district: data.district!,
      province: data.province!,
      region: data.region,
      latitude: Number(data.latitude),
      longitude: Number(data.longitude),
      totalAreaHa: totalArea,
      leasableAreaHa: leasableArea,
      occupancyRate: 0,
      remainingAreaHa: leasableArea,
      targetIndustries: industries,
    };

    if (data.nameEn) payload.nameEn = data.nameEn;
    if (data.operator) payload.operator = data.operator;

    const landRent = toNumOrUndef(data.landRentUsdM2Year);
    if (landRent != null) payload.landRentUsdM2Year = landRent;
    const rbfRent = toNumOrUndef(data.rbfRentUsdM2Month);
    if (rbfRent != null) payload.rbfRentUsdM2Month = rbfRent;
    const rbwRent = toNumOrUndef(data.rbwRentUsdM2Month);
    if (rbwRent != null) payload.rbwRentUsdM2Month = rbwRent;
    const mgmtFee = toNumOrUndef(data.managementFeeUsd);
    if (mgmtFee != null) payload.managementFeeUsd = mgmtFee;

    const year = toNumOrUndef(data.establishedYear);
    if (year != null) payload.establishedYear = year;
    const tenantCount = toNumOrUndef(data.tenantCount);
    if (tenantCount != null) payload.tenantCount = tenantCount;

    const infra = parseInfrastructure(data.infrastructure);
    if (infra) payload.infrastructure = infra;

    if (data.description) payload.description = data.description;
    if (data.descriptionEn) payload.descriptionEn = data.descriptionEn;

    mutation.mutate(payload);
  };

  return (
    <div className="mx-auto max-w-4xl space-y-4 sm:space-y-6">
      <div className="flex items-center justify-between gap-3">
        <div>
          <Link
            href="/industrial-parks"
            className="text-sm text-muted-foreground hover:text-foreground"
          >
            ← Danh sách KCN
          </Link>
          <h1 className="mt-1 text-xl font-bold sm:text-2xl">Thêm KCN</h1>
        </div>
      </div>

      {error && (
        <div className="rounded-md border border-destructive/50 bg-destructive/10 p-3 text-sm text-destructive">
          {error}
          <button className="ml-2 font-medium underline" onClick={() => setError(null)}>
            Đóng
          </button>
        </div>
      )}

      <form onSubmit={handleSubmit(onSubmit)} className="space-y-6">
        {/* Thông tin cơ bản */}
        <Card>
          <CardHeader>
            <CardTitle className="text-lg">Thông tin cơ bản</CardTitle>
          </CardHeader>
          <CardContent className="grid gap-4 sm:grid-cols-2">
            <div>
              <Label htmlFor="name">Tên KCN *</Label>
              <Input id="name" {...register('name')} />
              {errors.name && (
                <p className="mt-1 text-xs text-destructive">{errors.name.message}</p>
              )}
            </div>
            <div>
              <Label htmlFor="nameEn">Tên tiếng Anh</Label>
              <Input id="nameEn" {...register('nameEn')} />
            </div>
            <div>
              <Label htmlFor="slug">Slug *</Label>
              <Input id="slug" {...register('slug')} placeholder="vd: kcn-vsip-1" />
              {errors.slug && (
                <p className="mt-1 text-xs text-destructive">{errors.slug.message}</p>
              )}
            </div>
            <div>
              <Label htmlFor="status">Trạng thái *</Label>
              <Select id="status" {...register('status')}>
                {STATUS_OPTIONS.map((s) => (
                  <option key={s} value={s}>
                    {PARK_STATUS_LABELS[s]}
                  </option>
                ))}
              </Select>
            </div>
            <div>
              <Label htmlFor="developer">Chủ đầu tư *</Label>
              <Input id="developer" {...register('developer')} />
              {errors.developer && (
                <p className="mt-1 text-xs text-destructive">{errors.developer.message}</p>
              )}
            </div>
            <div>
              <Label htmlFor="operator">Đơn vị vận hành</Label>
              <Input id="operator" {...register('operator')} />
            </div>
            <div className="sm:col-span-2">
              <Label htmlFor="description">Mô tả</Label>
              <Textarea id="description" rows={3} {...register('description')} />
            </div>
            <div className="sm:col-span-2">
              <Label htmlFor="descriptionEn">Mô tả (Tiếng Anh)</Label>
              <Textarea id="descriptionEn" rows={3} {...register('descriptionEn')} />
            </div>
          </CardContent>
        </Card>

        {/* Vị trí */}
        <Card>
          <CardHeader>
            <CardTitle className="text-lg">Vị trí</CardTitle>
          </CardHeader>
          <CardContent className="grid gap-4 sm:grid-cols-2">
            <div className="sm:col-span-2">
              <Label htmlFor="address">Địa chỉ *</Label>
              <Input id="address" {...register('address')} />
              {errors.address && (
                <p className="mt-1 text-xs text-destructive">{errors.address.message}</p>
              )}
            </div>
            <div>
              <Label htmlFor="district">Quận/Huyện *</Label>
              <Input id="district" {...register('district')} />
              {errors.district && (
                <p className="mt-1 text-xs text-destructive">{errors.district.message}</p>
              )}
            </div>
            <div>
              <Label htmlFor="province">Tỉnh/Thành phố *</Label>
              <Input id="province" {...register('province')} />
              {errors.province && (
                <p className="mt-1 text-xs text-destructive">{errors.province.message}</p>
              )}
            </div>
            <div>
              <Label htmlFor="region">Vùng *</Label>
              <Select id="region" {...register('region')}>
                {REGION_OPTIONS.map((r) => (
                  <option key={r} value={r}>
                    {REGION_LABELS[r]}
                  </option>
                ))}
              </Select>
            </div>
            <div className="grid grid-cols-2 gap-4">
              <div>
                <Label htmlFor="latitude">Vĩ độ *</Label>
                <Input id="latitude" type="number" step="any" {...register('latitude')} />
                {errors.latitude && (
                  <p className="mt-1 text-xs text-destructive">{errors.latitude.message}</p>
                )}
              </div>
              <div>
                <Label htmlFor="longitude">Kinh độ *</Label>
                <Input id="longitude" type="number" step="any" {...register('longitude')} />
                {errors.longitude && (
                  <p className="mt-1 text-xs text-destructive">{errors.longitude.message}</p>
                )}
              </div>
            </div>
          </CardContent>
        </Card>

        {/* Quy mô & giá thuê */}
        <Card>
          <CardHeader>
            <CardTitle className="text-lg">Quy mô & giá thuê</CardTitle>
          </CardHeader>
          <CardContent className="grid gap-4 sm:grid-cols-2">
            <div>
              <Label htmlFor="totalAreaHa">Tổng diện tích (ha) *</Label>
              <Input
                id="totalAreaHa"
                type="number"
                step="any"
                {...register('totalAreaHa')}
              />
              {errors.totalAreaHa && (
                <p className="mt-1 text-xs text-destructive">{errors.totalAreaHa.message}</p>
              )}
            </div>
            <div>
              <Label htmlFor="leasableAreaHa">Diện tích cho thuê (ha) *</Label>
              <Input
                id="leasableAreaHa"
                type="number"
                step="any"
                {...register('leasableAreaHa')}
              />
              {errors.leasableAreaHa && (
                <p className="mt-1 text-xs text-destructive">{errors.leasableAreaHa.message}</p>
              )}
            </div>
            <div>
              <Label htmlFor="landRentUsdM2Year">Giá thuê đất (USD/m²/năm)</Label>
              <Input
                id="landRentUsdM2Year"
                type="number"
                step="any"
                {...register('landRentUsdM2Year')}
              />
            </div>
            <div>
              <Label htmlFor="rbfRentUsdM2Month">Giá thuê nhà xưởng (USD/m²/tháng)</Label>
              <Input
                id="rbfRentUsdM2Month"
                type="number"
                step="any"
                {...register('rbfRentUsdM2Month')}
              />
            </div>
            <div>
              <Label htmlFor="rbwRentUsdM2Month">Giá thuê kho (USD/m²/tháng)</Label>
              <Input
                id="rbwRentUsdM2Month"
                type="number"
                step="any"
                {...register('rbwRentUsdM2Month')}
              />
            </div>
            <div>
              <Label htmlFor="managementFeeUsd">Phí quản lý (USD)</Label>
              <Input
                id="managementFeeUsd"
                type="number"
                step="any"
                {...register('managementFeeUsd')}
              />
            </div>
            <div>
              <Label htmlFor="establishedYear">Năm thành lập</Label>
              <Input id="establishedYear" type="number" {...register('establishedYear')} />
            </div>
            <div>
              <Label htmlFor="tenantCount">Số khách thuê</Label>
              <Input id="tenantCount" type="number" {...register('tenantCount')} />
            </div>
          </CardContent>
        </Card>

        {/* Tiện ích & ngành nghề */}
        <Card>
          <CardHeader>
            <CardTitle className="text-lg">Tiện ích & ngành nghề</CardTitle>
          </CardHeader>
          <CardContent className="space-y-4">
            <div>
              <Label htmlFor="targetIndustries">Ngành nghề mục tiêu</Label>
              <Textarea
                id="targetIndustries"
                rows={2}
                placeholder="Phân tách bằng dấu phẩy, vd: Điện tử, Dệt may, Logistics"
                {...register('targetIndustries')}
              />
            </div>
            <div>
              <Label htmlFor="infrastructure">Hạ tầng & tiện ích</Label>
              <Textarea
                id="infrastructure"
                rows={4}
                placeholder={'Mỗi dòng một mục, dạng "key: value"\nvd:\nĐiện: 22kV\nNước: 5000 m³/ngày'}
                {...register('infrastructure')}
              />
            </div>
          </CardContent>
        </Card>

        <div className="flex justify-end gap-3">
          <Link href="/industrial-parks">
            <Button type="button" variant="outline">
              Huỷ
            </Button>
          </Link>
          <Button type="submit" disabled={mutation.isPending}>
            {mutation.isPending ? 'Đang lưu...' : 'Tạo KCN'}
          </Button>
        </div>
      </form>
    </div>
  );
}