import { Link, useNavigate, useParams } from '@tanstack/react-router'
import { Button, Checkbox, Stack, TextInput, Text, Anchor, Alert } from "@pikku/mantine/core"
import { Controller, useForm } from "react-hook-form"
import { requestMagicLink } from "@/lib/auth"
import { pikku } from "@/pikku/http"
import { useMutation, useQueryClient } from "@tanstack/react-query"
import { useI18n } from "@/context/i18n-provider"
import { useState } from "react"
import { asI18n } from "@pikku/react"

export const StartApplication: React.FunctionComponent<{ initializing: boolean }> = ({ initializing }) => {
    const navigate = useNavigate()
    const params = useParams({ strict: false })
    const lang = params.lang as string
    const t = useI18n()
    const [emailExists, setEmailExists] = useState(false)
    const [existingEmail, setExistingEmail] = useState('')
    const [hasError, setHasError] = useState(false)
    const {
        control,
        handleSubmit,
        formState: { errors },
    } = useForm({
        defaultValues: {
            email: '',
            fullName: '',
            termsAndPrivacyAccepted: false
        }
    })

    const queryClient = useQueryClient()
    const mutation = useMutation({
        mutationFn: async (data: any) => {
            if (data.termsAndPrivacyAccepted && data.fullName && data.email) {
                try {
                    await pikku().post('/candidate', {
                        name: data.fullName,
                        email: data.email
                    });
                    (window as any).fbq?.('trackCustom', 'StartApplication', {
                      source: 'check_my_qualification_button',
                      page: '/en/jobs/apply'
                    });
                    queryClient.invalidateQueries({ queryKey: ['candidate'] });
                    navigate({ to: `/${lang}/jobs/application` });
                } catch (error: any) {
                    if (error.status === 409) {
                        setEmailExists(true)
                        setExistingEmail(data.email)
                        setHasError(false)
                        throw error
                    }
                    setHasError(true)
                    setEmailExists(false)
                    throw error
                }
            }
        }
    })

    const sendMagicLinkMutation = useMutation({
        mutationFn: async () => {
            await requestMagicLink(existingEmail)
        }
    })

    return (
        <Stack component="form" gap="md" onSubmit={handleSubmit(data => mutation.mutateAsync(data))}>
            <Controller
                name="fullName"
                control={control}
                rules={{ required: t('jobs.startapplication.validation.fullnamerequired') }}
                disabled={initializing}
                render={({ field }) => (
                    <TextInput
                        id="fullName"
                        label={t('jobs.startapplication.fullname')}
                        error={errors.fullName?.message}
                        {...field}
                    />
                )}
            />

            <Controller
                name="email"
                control={control}
                rules={{
                    required: t('jobs.startapplication.validation.emailrequired'),
                    pattern: {
                        value: /^[^\s@]+@[^\s@]+\.[^\s@]+$/,
                        message: t('jobs.startapplication.validation.emailinvalid')
                    }
                }}
                disabled={initializing}
                render={({ field }) => (
                    <TextInput
                        id="email"
                        type="email"
                        label={t('jobs.startapplication.email')}
                        autoComplete="email"
                        error={errors.email?.message}
                        {...field}
                    />
                )}
            />

            <Controller
                name="termsAndPrivacyAccepted"
                control={control}
                disabled={initializing}
                rules={{ required: t('jobs.startapplication.validation.termsrequired') }}
                render={({ field }) => (
                    <Checkbox
                        id="terms"
                        checked={field.value}
                        onChange={field.onChange}
                        disabled={field.disabled}
                        error={errors.termsAndPrivacyAccepted?.message}
                        label={
                            <Text size="sm">
                                {t('jobs.startapplication.termstext.prefix')}{asI18n(' ')}
                                <Anchor component={Link} to={`/${lang}/legal/terms-and-conditions`} size="sm">
                                    {t('jobs.startapplication.termstext.terms')}
                                </Anchor>{asI18n(' ')}
                                {t('jobs.startapplication.termstext.and')}{asI18n(' ')}
                                <Anchor component={Link} to={`/${lang}/legal/privacy`} size="sm">
                                    {t('jobs.startapplication.termstext.privacy')}
                                </Anchor>{asI18n(' ')}
                                {t('jobs.startapplication.termstext.suffix')}
                            </Text>
                        }
                    />
                )}
            />

            {hasError && (
                <Alert color="red" title={t('jobs.startapplication.error.title')}>
                    <Text size="sm">
                        {t('jobs.startapplication.error.message')}
                    </Text>
                </Alert>
            )}

            {emailExists && (
                <Alert color="blue" title={t('jobs.startapplication.emailexists.title')}>
                    <Text size="sm" mb="md">
                        {t('jobs.startapplication.emailexists.message')}
                    </Text>
                    <Button
                        size="sm"
                        variant="light"
                        onClick={() => sendMagicLinkMutation.mutate()}
                        loading={sendMagicLinkMutation.isPending}
                        disabled={sendMagicLinkMutation.isSuccess}
                    >
                        {sendMagicLinkMutation.isSuccess
                            ? t('jobs.startapplication.emailexists.sent')
                            : t('jobs.startapplication.emailexists.button')}
                    </Button>
                </Alert>
            )}

            <Stack gap="xs">
                <Button
                    size="lg"
                    type="submit"
                    loading={mutation.isPending}
                    disabled={initializing || mutation.isPending}
                    px="xl"
                >
                    {t('jobs.startapplication.checkqualification')}
                </Button>
                <Text size="sm" c="dimmed" ta="center">
                    {t('jobs.startapplication.freetext')}
                </Text>
            </Stack>
        </Stack>
    );
}