import { useEffect, useState } from 'react';
import styled from 'styled-components';
import type { Gender, User } from '../../types/user';
import { TagsInput } from './TagsInput';

interface PersonModalProps {
    isOpen: boolean;
    user: User | null;
    availableTags: string[];
    onClose: () => void;
    onSave: (user: User) => void;
}

interface PersonForm {
    name: string;
    gender: Gender;
    age: string;
    weight: string;
    height: string;
    avoid: string[];
    favorite: string[];
}

const defaultForm: PersonForm = {
    name: '',
    gender: 'm',
    age: '',
    weight: '',
    height: '',
    avoid: [],
    favorite: [],
};

export function PersonModal({
                                isOpen,
                                user,
                                availableTags,
                                onClose,
                                onSave,
                            }: PersonModalProps) {
    const [form, setForm] = useState<PersonForm>(defaultForm);

    useEffect(() => {
        if (!isOpen) return;

        if (user) {
            setForm({
                name: user.name,
                gender: user.gender,
                age: String(user.age),
                weight: user.weight ? String(user.weight) : '',
                height: user.height ? String(user.height) : '',
                avoid: user.avoid ?? [],
                favorite: user.favorite ?? [],
            });
        } else {
            setForm(defaultForm);
        }
    }, [isOpen, user]);

    if (!isOpen) return null;

    function updateForm<TName extends keyof PersonForm>(name: TName, value: PersonForm[TName]) {
        setForm(current => ({
            ...current,
            [name]: value,
        }));
    }

    function handleAvoidChange(tags: string[]) {
        setForm(current => ({
            ...current,
            avoid: tags,
            favorite: current.favorite.filter(tag => !tags.includes(tag)),
        }));
    }

    function handleFavoriteChange(tags: string[]) {
        setForm(current => ({
            ...current,
            favorite: tags,
            avoid: current.avoid.filter(tag => !tags.includes(tag)),
        }));
    }

    function handleSave() {
        const age = Number(form.age);

        if (!form.name.trim()) {
            alert('Пожалуйста, введите имя.');
            return;
        }

        if (!age || age < 7) {
            alert('Возраст должен быть от 7 лет.');
            return;
        }

        onSave({
            id: user?.id,
            name: form.name.trim(),
            gender: form.gender,
            age,
            weight: form.weight ? Number(form.weight) : undefined,
            height: form.height ? Number(form.height) : undefined,
            avoid: form.avoid,
            favorite: form.favorite,
        });
    }

    return (
        <Overlay onClick={onClose}>
            <Content onClick={event => event.stopPropagation()}>
                <Header>
                    <h2>{user ? 'Редактировать человека' : 'Добавить человека'}</h2>
                    <CloseButton type="button" onClick={onClose}>
                        ×
                    </CloseButton>
                </Header>

                <FormGroup>
                    <label>Имя</label>
                    <input
                        type="text"
                        placeholder="Имя"
                        value={form.name}
                        onChange={event => updateForm('name', event.target.value)}
                    />
                </FormGroup>

                <FormGroup>
                    <label>Пол</label>
                    <GenderToggles>
                        <GenderButton
                            type="button"
                            $active={form.gender === 'f'}
                            onClick={() => updateForm('gender', 'f')}
                        >
                            Женский
                        </GenderButton>
                        <GenderButton
                            type="button"
                            $active={form.gender === 'm'}
                            onClick={() => updateForm('gender', 'm')}
                        >
                            Мужской
                        </GenderButton>
                    </GenderToggles>
                </FormGroup>

                <FormRow>
                    <FormGroup>
                        <label>Возраст</label>
                        <input
                            type="number"
                            value={form.age}
                            onChange={event => updateForm('age', event.target.value)}
                        />
                        <Hint>от 7 лет</Hint>
                    </FormGroup>

                    <FormGroup>
                        <label>Вес</label>
                        <input
                            type="number"
                            value={form.weight}
                            onChange={event => updateForm('weight', event.target.value)}
                        />
                    </FormGroup>

                    <FormGroup>
                        <label>Рост</label>
                        <input
                            type="number"
                            value={form.height}
                            onChange={event => updateForm('height', event.target.value)}
                        />
                    </FormGroup>
                </FormRow>

                <PrefsGrid>
                    <TagsInput
                        title="Запрещённые"
                        type="avoid"
                        value={form.avoid}
                        availableTags={availableTags}
                        excludedTags={form.favorite}
                        onChange={handleAvoidChange}
                    />

                    <TagsInput
                        title="Любимые"
                        type="favorite"
                        value={form.favorite}
                        availableTags={availableTags}
                        excludedTags={form.avoid}
                        onChange={handleFavoriteChange}
                    />
                </PrefsGrid>

                <SaveButton type="button" onClick={handleSave}>
                    Сохранить
                </SaveButton>
            </Content>
        </Overlay>
    );
}

const Overlay = styled.div`
    position: fixed;
    inset: 0;
    background: rgba(0, 0, 0, 0.4);
    backdrop-filter: blur(2px);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 1000;
    padding: 20px;
`;

const Content = styled.div`
    background: #ffffff;
    border-radius: 24px;
    width: 100%;
    max-width: 440px;
    padding: 24px;
    box-shadow: 0 8px 30px rgba(0, 0, 0, 0.2);
    max-height: 95vh;
    overflow-y: auto;
`;

const Header = styled.div`
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 20px;

    h2 {
        font-size: 20px;
        font-weight: 600;
        color: ${({ theme }) => theme.colors.darkGreen};
    }
`;

const CloseButton = styled.button`
    font-size: 24px;
    color: #b0b0b0;
    cursor: pointer;
    line-height: 1;
    background: transparent;
    border: 0;

    &:hover {
        color: ${({ theme }) => theme.colors.darkGreen};
    }
`;

const FormGroup = styled.div`
    margin-bottom: 16px;
    flex: 1;

    label {
        display: block;
        font-size: 14px;
        color: ${({ theme }) => theme.colors.darkGreen};
        margin-bottom: 6px;
    }

    input {
        width: 100%;
        padding: 10px 12px;
        border: 1px solid #e1e1e1;
        border-radius: 8px;
        font-size: 14px;
        outline: none;
        transition: 0.2s;

        &:focus {
            border-color: ${({ theme }) => theme.colors.green};
        }
    }
`;

const FormRow = styled.div`
    display: flex;
    gap: 16px;
    margin-bottom: 16px;

    ${FormGroup} {
        margin-bottom: 0;
    }

    @media (max-width: 600px) {
        flex-direction: column;
    }
`;

const Hint = styled.span`
    display: block;
    font-size: 12px;
    color: ${({ theme }) => theme.colors.gray};
    margin-top: 4px;
`;

const GenderToggles = styled.div`
    display: flex;
    gap: 8px;
    margin-bottom: 16px;
`;

const GenderButton = styled.button<{ $active: boolean }>`
    flex: 1;
    padding: 10px;
    border: 1px solid ${({ $active }) => ($active ? '#e9f6d9' : '#e1e1e1')};
    border-radius: 8px;
    background: ${({ $active }) => ($active ? '#e9f6d9' : '#ffffff')};
    font-size: 14px;
    cursor: pointer;
    transition: 0.2s;
    font-weight: ${({ $active }) => ($active ? 500 : 400)};
`;

const PrefsGrid = styled.div`
    display: flex;
    gap: 16px;
    margin-bottom: 20px;
    border-top: 1px solid #f0f0f0;
    padding-top: 16px;

    @media (max-width: 600px) {
        flex-direction: column;
    }
`;

const SaveButton = styled.button`
    width: 100%;
    padding: 12px;
    background: ${({ theme }) => theme.colors.green};
    color: #fff;
    border: none;
    border-radius: 12px;
    font-size: 16px;
    font-weight: 600;
    cursor: pointer;
    transition: 0.2s;

    &:hover {
        background: #5b8f29;
    }
`;