import React, { useState, useEffect } from 'react'
import { useForm } from 'react-hook-form'
import { zodResolver } from '@hookform/resolvers/zod'
import { z } from 'zod'
import { Link } from 'react-router-dom'
import {
  Box,
  Button,
  Input,
  VStack,
  HStack,
  Text,
  Heading,
  Card,
  Textarea,
  Stack,
} from '@chakra-ui/react'
import { Field } from '../../components/ui/field'
import { cigarettesApi } from '../../api/client'
import { URLs } from '../../__data__/urls'
import type { Cigarette } from '../../types/api'

const logCigaretteSchema = z.object({
  smokedAt: z.string().optional(),
  note: z.string().optional(),
})

type LogCigaretteFormData = z.infer<typeof logCigaretteSchema>

export const TrackerPage: React.FC = () => {
  const [cigarettes, setCigarettes] = useState<Cigarette[]>([])
  const [isLoading, setIsLoading] = useState(false)
  const [error, setError] = useState<string | null>(null)
  const [success, setSuccess] = useState<string | null>(null)

  const {
    register,
    handleSubmit,
    reset,
    formState: { errors },
  } = useForm<LogCigaretteFormData>({
    resolver: zodResolver(logCigaretteSchema),
  })

  const fetchCigarettes = async () => {
    try {
      const response = await cigarettesApi.getAll()
      if (response.success) {
        // Show most recent first
        setCigarettes(response.body.reverse())
      }
    } catch (err: any) {
      console.error('Failed to fetch cigarettes:', err)
    }
  }

  useEffect(() => {
    fetchCigarettes()
  }, [])

  const logQuick = async () => {
    setIsLoading(true)
    setError(null)
    setSuccess(null)

    try {
      const response = await cigarettesApi.log({})
      if (response.success) {
        setSuccess('Сигарета записана!')
        await fetchCigarettes()
        setTimeout(() => setSuccess(null), 3000)
      }
    } catch (err: any) {
      const errorMessage = err?.response?.data?.errors || err?.response?.data?.message || 'Ошибка при записи'
      setError(errorMessage)
    } finally {
      setIsLoading(false)
    }
  }

  const onSubmit = async (data: LogCigaretteFormData) => {
    setIsLoading(true)
    setError(null)
    setSuccess(null)

    try {
      const response = await cigarettesApi.log({
        smokedAt: data.smokedAt || undefined,
        note: data.note || undefined,
      })
      if (response.success) {
        setSuccess('Сигарета записана с заметкой!')
        reset()
        await fetchCigarettes()
        setTimeout(() => setSuccess(null), 3000)
      }
    } catch (err: any) {
      const errorMessage = err?.response?.data?.errors || err?.response?.data?.message || 'Ошибка при записи'
      setError(errorMessage)
    } finally {
      setIsLoading(false)
    }
  }

  const formatDate = (dateString: string) => {
    const date = new Date(dateString)
    return date.toLocaleString('ru-RU', {
      day: '2-digit',
      month: '2-digit',
      year: 'numeric',
      hour: '2-digit',
      minute: '2-digit',
    })
  }

  return (
    <Box minH="100vh" bg="gray.50" p={{ base: 2, md: 8 }}>
      <VStack gap={6} maxW="4xl" mx="auto">
        <Heading size={{ base: 'xl', md: '2xl' }}>Трекер курения</Heading>

        <HStack w="full" gap={4}>
          <Link to={URLs.baseUrl}>
            <Button colorScheme="gray" variant="outline">
              На главную
            </Button>
          </Link>
          <Link to={URLs.baseUrl + '/stats'}>
            <Button colorScheme="teal" variant="outline">
              Статистика
            </Button>
          </Link>
        </HStack>

        {/* Quick log button */}
        <Card.Root w="full" bg="blue.50">
          <Card.Body p={{ base: 4, md: 6 }}>
            <VStack gap={4}>
              <Text fontSize="lg" fontWeight="bold">
                Быстрая запись
              </Text>
              <Button
                colorScheme="blue"
                size="lg"
                w="full"
                onClick={logQuick}
                disabled={isLoading}
              >
                {isLoading ? 'Запись...' : 'Записать сигарету (текущее время)'}
              </Button>
            </VStack>
          </Card.Body>
        </Card.Root>

        {/* Form with custom time and note */}
        <Card.Root w="full">
          <Card.Body p={{ base: 4, md: 6 }}>
            <form onSubmit={handleSubmit(onSubmit)}>
              <VStack gap={4} align="stretch">
                <Heading size="md">Запись с дополнительными данными</Heading>

                <Field
                  label="Время (необязательно)"
                  helperText="Оставьте пустым для текущего времени"
                  invalid={!!errors.smokedAt}
                  errorText={errors.smokedAt?.message}
                >
                  <Input
                    {...register('smokedAt')}
                    type="datetime-local"
                    placeholder="Выберите время"
                  />
                </Field>

                <Field
                  label="Заметка (необязательно)"
                  invalid={!!errors.note}
                  errorText={errors.note?.message}
                >
                  <Textarea
                    {...register('note')}
                    placeholder="Добавьте комментарий..."
                    rows={3}
                  />
                </Field>

                <Button
                  type="submit"
                  colorScheme="green"
                  w="full"
                  disabled={isLoading}
                >
                  {isLoading ? 'Запись...' : 'Записать с заметкой'}
                </Button>
              </VStack>
            </form>
          </Card.Body>
        </Card.Root>

        {/* Success/Error messages */}
        {success && (
          <Card.Root w="full" bg="green.50" borderColor="green.500" borderWidth={2}>
            <Card.Body>
              <Text color="green.700" fontWeight="bold">
                {success}
              </Text>
            </Card.Body>
          </Card.Root>
        )}

        {error && (
          <Card.Root w="full" bg="red.50" borderColor="red.500" borderWidth={2}>
            <Card.Body>
              <Text color="red.700" fontWeight="bold">
                {error}
              </Text>
            </Card.Body>
          </Card.Root>
        )}

        {/* Recent cigarettes list */}
        <Card.Root w="full">
          <Card.Body p={{ base: 4, md: 6 }}>
            <VStack gap={4} align="stretch">
              <Heading size="md">Последние записи</Heading>

              {cigarettes.length === 0 ? (
                <Text color="gray.500" textAlign="center" py={4}>
                  Записей пока нет
                </Text>
              ) : (
                <Stack gap={2}>
                  {cigarettes.slice(0, 10).map((cigarette) => (
                    <Box
                      key={cigarette.id}
                      p={3}
                      bg="gray.100"
                      borderRadius="md"
                      borderWidth={1}
                      borderColor="gray.300"
                    >
                      <HStack justify="space-between" align="start">
                        <VStack align="start" gap={1}>
                          <Text fontWeight="bold">
                            {formatDate(cigarette.smokedAt)}
                          </Text>
                          {cigarette.note && (
                            <Text fontSize="sm" color="gray.600">
                              {cigarette.note}
                            </Text>
                          )}
                        </VStack>
                      </HStack>
                    </Box>
                  ))}
                </Stack>
              )}
            </VStack>
          </Card.Body>
        </Card.Root>
      </VStack>
    </Box>
  )
}