import PortalFrame from '../../membership/portal/portal-frame';
import toast from 'react-hot-toast';
import {Button} from '@tryghost/admin-x-design-system';
import {type ErrorMessages, useForm} from '@tryghost/admin-x-framework/hooks';
import {Form, Icon, PreviewModalContent, Select, type SelectOption, TextArea, TextField, showToast} from '@tryghost/admin-x-design-system';
import {JSONError} from '@tryghost/admin-x-framework/errors';
import {getHomepageUrl} from '@tryghost/admin-x-framework/api/site';
import {getOfferPortalPreviewUrl, type offerPortalPreviewUrlTypes} from '../../../../utils/get-offers-portal-preview-url';
import {getPaidActiveTiers, useBrowseTiers} from '@tryghost/admin-x-framework/api/tiers';
import {getTiersCadences} from '../../../../utils/get-tiers-cadences';
import {useAddOffer} from '@tryghost/admin-x-framework/api/offers';
import {useBrowseOffers} from '@tryghost/admin-x-framework/api/offers';
import {useEffect, useMemo, useState} from 'react';
import {useGlobalData} from '../../../providers/global-data-provider';
import {useRouting} from '@tryghost/admin-x-framework/routing';

// we should replace this with a library
function slugify(text: string): string {
    return text
        .toString()
        .toLowerCase()
        .trim()
        .replace(/\s+/g, '-')
        .replace(/[^\w\-]+/g, '')
        .replace(/\-\-+/g, '-');
}

export interface OfferType {
    title: string;
    description: string;
}

const MAX_DISPLAY_TEXT_LENGTH = 191;

export const ButtonSelect: React.FC<{type: OfferType, checked: boolean, onClick: () => void}> = ({type, checked, onClick}) => {
    const checkboxClass = checked ? 'bg-black text-white dark:bg-white dark:text-black' : 'border border-grey-300 dark:border-grey-800';

    return (
        <button className='text-left' type='button' onClick={onClick}>
            <div className='flex gap-3'>
                <div className={`mt-0.5 flex size-4 items-center justify-center rounded-full ${checkboxClass}`}>
                    {checked ? <Icon className='w-[7px] stroke-[4]' name='check' size='custom' /> : null}
                </div>
                <div className='-mt-px flex flex-col'>
                    <span>{type.title}</span>
                    <span className='text-sm'>{type.description}</span>
                </div>
            </div>
        </button>
    );
};

type formStateTypes = {
    disableBackground?: boolean;
    name: string;
    code: {
        isDirty: boolean;
        value: string;
    };
    displayTitle: {
        isDirty: boolean;
        value: string;
    };
    displayDescription: string;
    type: string;
    cadence: string;
    amount: number;
    duration: string;
    durationInMonths: number;
    currency: string;
    status: string;
    tierId: string;
    fixedAmount?: number;
    trialAmount?: number;
    percentAmount?: number;
};

const calculateAmount = (formState: formStateTypes): number => {
    const {fixedAmount = 0, percentAmount = 0, trialAmount = 0, amount = 0} = formState;

    switch (formState.type) {
    case 'fixed':
        return fixedAmount * 100;
    case 'percent':
        return percentAmount;
    case 'trial':
        return trialAmount;
    default:
        return amount;
    }
};

type SidebarProps = {
    tierOptions: SelectOption[];
    handleTierChange: (tier: SelectOption) => void;
    selectedTier: SelectOption;
    overrides: formStateTypes;
    // handleTextInput: (e: React.ChangeEvent<HTMLInputElement>, key: keyof offerPortalPreviewUrlTypes) => void;
    amountOptions: SelectOption[];
    typeOptions: OfferType[];
    durationOptions: SelectOption[];
    handleTypeChange: (type: string) => void;
    handleDurationChange: (duration: string) => void;
    handleAmountTypeChange: (amountType: string) => void;
    handleNameInput: (e: React.ChangeEvent<HTMLInputElement>) => void;
    handleTextAreaInput: (e: React.ChangeEvent<HTMLTextAreaElement>) => void;
    handleDisplayTitleInput: (e: React.ChangeEvent<HTMLInputElement>) => void;
    handleAmountInput: (e: React.ChangeEvent<HTMLInputElement>) => void;
    handleDurationInMonthsInput: (e: React.ChangeEvent<HTMLInputElement>) => void;
    handleCodeInput: (e: React.ChangeEvent<HTMLInputElement>) => void;
    validate: () => void;
    clearError: (field: string) => void;
    testId: string;
    errors: ErrorMessages;
    handleTrialAmountInput: (e: React.ChangeEvent<HTMLInputElement>) => void;
};

const Sidebar: React.FC<SidebarProps> = ({tierOptions,
    handleTierChange,
    selectedTier,
    // handleTextInput,
    typeOptions,
    durationOptions,
    handleTypeChange,
    handleDurationChange,
    overrides,
    handleAmountTypeChange,
    handleNameInput,
    handleTextAreaInput,
    handleDisplayTitleInput,
    handleDurationInMonthsInput,
    handleAmountInput,
    handleCodeInput,
    clearError,
    errors,
    testId,
    handleTrialAmountInput,
    amountOptions}) => {
    // const handleError = useHandleError();
    const isYearlyTier = overrides.cadence === 'year';
    const filteredDurationOptions = isYearlyTier
        ? durationOptions.filter(option => option.value !== 'repeating')
        : durationOptions;

    const [nameLength, setNameLength] = useState(0);
    const nameLengthColor = nameLength > 40 ? 'text-red' : 'text-green';

    const {siteData} = useGlobalData();
    const [isCopied, setIsCopied] = useState(false);
    const homepageUrl = getHomepageUrl(siteData!);
    const offerUrl = `${homepageUrl}${overrides.code.value}`;
    const handleCopyClick = async () => {
        await navigator.clipboard.writeText(offerUrl);
        setIsCopied(true);
        setTimeout(() => setIsCopied(false), 2000);
    };

    return (
        <div className='pt-7' data-testId={testId}>
            <Form>
                <section>
                    <h2 className='mb-4 text-lg'>General</h2>
                    <div className='flex flex-col gap-6'>
                        <TextField
                            error={Boolean(errors.name)}
                            hint={errors.name || <div className='flex justify-between'><span>Visible to members on Stripe Checkout page</span><strong><span className={`${nameLengthColor}`}>{nameLength}</span> / 40</strong></div>}
                            maxLength={40}
                            placeholder='Black Friday'
                            title='Offer name'
                            onChange={(e) => {
                                handleNameInput(e);
                                setNameLength(e.target.value.length);
                            }}
                            onKeyDown={() => clearError('name')}
                        />
                        <TextField
                            error={Boolean(errors.displayTitle)}
                            hint={errors.displayTitle}
                            maxLength={MAX_DISPLAY_TEXT_LENGTH}
                            placeholder='Black Friday Special'
                            title='Display title'
                            value={overrides.displayTitle.value}
                            onChange={(e) => {
                                handleDisplayTitleInput(e);
                            }}
                            onKeyDown={() => clearError('displayTitle')}
                        />
                        <TextArea
                            maxLength={MAX_DISPLAY_TEXT_LENGTH}
                            placeholder='Take advantage of this limited-time offer.'
                            title='Display description'
                            value={overrides.displayDescription}
                            onChange={(e) => {
                                handleTextAreaInput(e);
                            }}
                        />
                    </div>
                </section>
                <section className='mt-4'>
                    <h2 className='mb-4 text-lg'>Details</h2>
                    <div className='flex flex-col gap-6'>
                        <div className='flex flex-col gap-4 rounded-md border border-grey-200 p-4 dark:border-grey-800'>
                            <ButtonSelect checked={overrides.type !== 'trial' ? true : false} type={typeOptions[0]} onClick={() => {
                                handleTypeChange('percent');
                            }} />
                            <ButtonSelect checked={overrides.type === 'trial' ? true : false} type={typeOptions[1]} onClick={() => {
                                handleTypeChange('trial');
                            }} />
                        </div>
                        <Select
                            options={tierOptions}
                            selectedOption={selectedTier}
                            testId='tier-cadence-select-offers'
                            title='Tier — Cadence'
                            onSelect={(e) => {
                                if (e) {
                                    handleTierChange(e);
                                }
                            }}
                        />
                        {
                            overrides.type !== 'trial' && <> <div className='relative'>
                                <TextField
                                    error={Boolean(errors.amount)}
                                    hint={errors.amount}
                                    title='Amount off'
                                    type='number'
                                    value={
                                        overrides.type === 'fixed'
                                            ? (overrides.fixedAmount === 0 ? '' : overrides.fixedAmount?.toString())
                                            : (overrides.percentAmount === 0 ? '' : overrides.percentAmount?.toString())
                                    }
                                    onChange={(e) => {
                                        handleAmountInput(e);
                                    }}
                                    onKeyDown={() => clearError('amount')}
                                />
                                <div className='absolute top-6 right-1.5 z-10'>
                                    <Select
                                        clearBg={true}
                                        controlClasses={{menu: 'w-20 right-0'}}
                                        options={amountOptions}
                                        selectedOption={overrides.type === 'percent' ? amountOptions[0] : amountOptions[1]}
                                        testId='amount-type-select-offers'
                                        onSelect={(e) => {
                                            handleAmountTypeChange(e?.value || '');
                                        }}
                                    />
                                </div>
                            </div>
                            <Select
                                options={filteredDurationOptions}
                                selectedOption={filteredDurationOptions.find(option => option.value === overrides.duration)}
                                testId='duration-select-offers'
                                title='Duration'
                                onSelect={(e) => {
                                    clearError('durationInMonths');
                                    handleDurationChange(e?.value || '');
                                }}
                            />

                            {
                                overrides.duration === 'repeating' && !isYearlyTier && <div className='-mt-4'>
                                    <TextField
                                        data-testid='duration-months-input'
                                        error={Boolean(errors.durationInMonths)}
                                        hint={errors.durationInMonths}
                                        rightPlaceholder={`${overrides.durationInMonths === 1 ? 'month' : 'months'}`}
                                        type='number'
                                        value={overrides.durationInMonths === 0 ? '' : String(overrides.durationInMonths)}
                                        onChange={(e) => {
                                            handleDurationInMonthsInput(e);
                                        }}
                                        onKeyDown={() => clearError('durationInMonths')}
                                    />
                                </div>
                            }
                            </>
                        }

                        {
                            overrides.type === 'trial' && <TextField
                                error={Boolean(errors.amount)}
                                hint={errors.amount}
                                title='Trial duration'
                                type='number'
                                value={overrides.trialAmount?.toString()}
                                onChange={(e) => {
                                    handleTrialAmountInput(e);
                                }}
                                onKeyDown={() => clearError('amount')}/>

                        }

                        <TextField
                            error={Boolean(errors.code)}
                            hint={errors.code || (overrides.code.value !== '' ? <div className='flex items-center justify-between'><div>{homepageUrl}<span className='font-bold'>{overrides.code.value}</span></div><span></span><Button className='text-xs' color='green' label={`${isCopied ? 'Copied' : 'Copy'}`} size='sm' link onClick={handleCopyClick} /></div> : null)}
                            placeholder='black-friday'
                            title='Offer code'
                            value={overrides.code.value}
                            onChange={(e) => {
                                handleCodeInput(e);
                            }}
                            onKeyDown={() => clearError('code')}
                        />
                    </div>
                </section>
            </Form>
        </div>
    );
};

const parseData = (input: string): { id: string; period: string; currency: string } => {
    const [id, period, currency] = input.split('-');
    if (!id || !period || !currency) {
        throw new Error('Invalid input format. Expected format is: id-period-currency');
    }
    return {id, period, currency};
};

const AddOfferModal = () => {
    const {siteData} = useGlobalData();
    const typeOptions = [
        {title: 'Discount', description: 'Offer a special reduced price', value: 'percent'},
        {title: 'Free trial', description: 'Give free access for a limited time', value: 'trial'}
    ];

    const durationOptions = [
        {value: 'once', label: 'First-payment'},
        {value: 'repeating', label: 'Multiple-months'},
        {value: 'forever', label: 'Forever'}
    ];

    const [href, setHref] = useState<string>('');
    const {updateRoute} = useRouting();
    const {data: {tiers} = {}} = useBrowseTiers();
    const activeTiers = getPaidActiveTiers(tiers || []);
    const tierCadenceOptions = getTiersCadences(activeTiers);
    const {mutateAsync: addOffer} = useAddOffer();
    const [selectedTier, setSelectedTier] = useState({
        tier: tierCadenceOptions[0] || {},
        dataset: {
            id: tierCadenceOptions[0]?.value ? parseData(tierCadenceOptions[0]?.value).id : '',
            period: tierCadenceOptions[0]?.value ? parseData(tierCadenceOptions[0]?.value).period : '',
            currency: tierCadenceOptions[0]?.value ? parseData(tierCadenceOptions[0]?.value).currency : ''
        }
    });

    const {data: {offers: allOffers = []} = {}} = useBrowseOffers();

    const {formState, updateForm, handleSave, saveState, okProps, validate, errors, clearError} = useForm({
        initialState: {
            disableBackground: false,
            name: '',
            code: {
                isDirty: false,
                value: ''
            },
            displayTitle: {
                isDirty: false,
                value: ''
            },
            displayDescription: '',
            type: 'percent',
            cadence: selectedTier?.dataset?.period || '',
            amount: 0,
            duration: 'once',
            durationInMonths: 1,
            currency: selectedTier?.dataset?.currency || 'USD',
            status: 'active',
            tierId: selectedTier?.dataset?.id || '',
            trialAmount: 7,
            fixedAmount: 0,
            percentAmount: 0
        },
        onSave: async () => {
            const duration = formState.type === 'trial' ? 'trial' : formState.duration;
            const dataset = {
                name: formState.name,
                code: formState.code.value,
                display_title: formState.displayTitle.value,
                display_description: formState.displayDescription,
                cadence: formState.cadence,
                amount: calculateAmount(formState) || 0,
                duration,
                ...(duration === 'repeating' ? {duration_in_months: formState.durationInMonths} : {}),
                currency: formState.currency,
                status: formState.status,
                redemption_type: 'signup' as const,
                tier: {
                    id: formState.tierId
                },
                type: formState.type,
                currency_restriction: false
            };

            const response = await addOffer(dataset);

            if (response && response.offers && response.offers.length > 0) {
                updateRoute(`offers/success/${response.offers[0].id}`);
            }
        },
        onSaveError: () => {},
        onValidate: () => {
            const newErrors : Record<string, string> = {};

            if (!formState.name && formState.name.length === 0) {
                newErrors.name = 'Name is required';
            }

            if (!formState.code.value && formState.code.value.length === 0) {
                newErrors.code = 'Code is required';
            }

            if (!formState.displayTitle.value && formState.displayTitle.value.length === 0) {
                newErrors.displayTitle = 'Display title is required';
            }

            if (formState.type === 'percent' && formState.percentAmount === 0) {
                newErrors.amount = 'Enter an amount greater than 0.';
            }

            if (formState.type === 'percent' && (formState.percentAmount < 1 || formState.percentAmount > 100)) {
                newErrors.amount = 'Enter an amount between 1 and 100%.';
            }

            if (formState.type === 'fixed' && formState.fixedAmount === 0 || formState.type === 'fixed' && formState.fixedAmount < 1) {
                newErrors.amount = 'Enter an amount greater than 0.';
            }

            if (formState.type === 'trial' && formState.trialAmount === 0) {
                newErrors.amount = 'Enter an amount greater than 0.';
            }

            if (formState.type === 'trial' && formState.trialAmount < 1) {
                newErrors.amount = 'Free trial must be at least 1 day.';
            }

            if (formState.type !== 'trial' && formState.duration === 'repeating' && (!Number.isInteger(formState.durationInMonths) || formState.durationInMonths < 1)) {
                newErrors.durationInMonths = 'Enter a whole number of months (1 or more).';
            }

            return newErrors;
        },
        savingDelay: 500
    });

    const amountOptions = [
        {value: 'percent', label: '%'},
        {value: 'fixed', label: formState.currency}
    ];

    const handleTierChange = (tier: SelectOption) => {
        const parsedTier = parseData(tier.value);
        const isYearlyCadence = parsedTier.period === 'year';

        setSelectedTier({
            tier,
            dataset: parsedTier
        });
        updateForm(state => ({
            ...state,
            cadence: parsedTier.period,
            currency: parsedTier.currency,
            tierId: parsedTier.id,
            duration: isYearlyCadence && state.duration === 'repeating' ? 'once' : state.duration
        }));

        if (isYearlyCadence) {
            clearError('durationInMonths');
        }
    };

    const handleTypeChange = (type: string) => {
        if (type === 'trial') {
            clearError('amount');
            clearError('durationInMonths');
        }

        updateForm(state => ({
            ...state,
            type: type
        }));
    };

    const handleAmountTypeChange = (amountType: string) => {
        updateForm(state => ({
            ...state,
            type: amountType === 'percent' ? 'percent' : 'fixed'
        }));
    };

    const handleAmountInput = (e: React.ChangeEvent<HTMLInputElement>) => {
        const target = e.target as HTMLInputElement;

        if (formState.type === 'fixed') {
            updateForm(state => ({
                ...state,
                fixedAmount: Number(target.value)
            }));
        } else if (formState.type === 'percent') {
            updateForm(state => ({
                ...state,
                percentAmount: Number(target.value)
            }));
        } else {
            updateForm(state => ({
                ...state,
                amount: Number(target.value)
            }));
        }
    };

    const handleDurationInMonthsInput = (e: React.ChangeEvent<HTMLInputElement>) => {
        const target = e.target as HTMLInputElement;
        const nextValue = Number(target.value);

        updateForm(state => ({
            ...state,
            durationInMonths: Number.isNaN(nextValue) ? 0 : nextValue
        }));
    };

    const handleNameInput = (e: React.ChangeEvent<HTMLInputElement>) => {
        const newValue = e.target.value;
        updateForm((prevOverrides) => {
            let newOverrides = {...prevOverrides};
            newOverrides.name = newValue;
            if (!prevOverrides.code.isDirty) {
                clearError('code');
                newOverrides.code = {
                    ...prevOverrides.code,
                    value: slugify(newValue)
                };
            }
            if (!prevOverrides.displayTitle.isDirty) {
                clearError('displayTitle');
                newOverrides.displayTitle = {
                    ...prevOverrides.displayTitle,
                    value: newValue
                };
            }
            return newOverrides;
        });
    };

    const handleDisplayTitleInput = (e: React.ChangeEvent<HTMLInputElement>) => {
        const target = e.target as HTMLInputElement;
        updateForm(state => ({
            ...state,
            displayTitle: {
                ...state.displayTitle,
                isDirty: true,
                value: target.value
            }
        }));
    };

    const handleTextAreaInput = (e: React.ChangeEvent<HTMLTextAreaElement>) => {
        const target = e.target as HTMLTextAreaElement;
        updateForm(state => ({
            ...state,
            displayDescription: target.value
        }));
    };

    const handleTrialAmountInput = (e: React.ChangeEvent<HTMLInputElement>) => {
        const target = e.target as HTMLInputElement;
        updateForm(state => ({
            ...state,
            trialAmount: Number(target.value)
        }));
    };

    const handleDurationChange = (duration: string) => {
        updateForm(state => ({
            ...state,
            duration: duration
        }));
    };

    const handleCodeInput = (e: React.ChangeEvent<HTMLInputElement>) => {
        const target = e.target as HTMLInputElement;
        updateForm(state => ({
            ...state,
            code: {
                ...state.code,
                isDirty: true,
                value: target.value
            }
        }));
    };

    const cancelAddOffer = () => {
        if (allOffers.length > 0) {
            updateRoute('offers/edit');
        } else {
            updateRoute('offers');
        }
    };

    const overrides : offerPortalPreviewUrlTypes = useMemo(() => {
        return {
            name: formState.name || '',
            code: formState.code.value || '',
            displayTitle: formState.displayTitle.value || '',
            displayDescription: formState.displayDescription || '',
            type: formState.type || 'percent',
            cadence: formState.cadence || 'month',
            amount: calculateAmount(formState) || 0,
            duration: formState.type === 'trial' ? 'trial' : formState.duration || 'once',
            durationInMonths: formState.durationInMonths || 0,
            currency: formState.currency || 'USD',
            status: formState.status || 'active',
            tierId: formState.tierId || activeTiers[0]?.id,
            redemptionType: 'signup'
        };
    }, [formState, activeTiers]);

    useEffect(() => {
        const newHref = getOfferPortalPreviewUrl(overrides, siteData.url);
        setHref(newHref);
    }, [formState, siteData.url, formState.type, overrides]);

    const sidebar = <Sidebar
        amountOptions={amountOptions as SelectOption[]}
        clearError={clearError}
        durationOptions={durationOptions}
        errors={errors}
        handleAmountInput={handleAmountInput}
        handleAmountTypeChange={handleAmountTypeChange}
        handleCodeInput={handleCodeInput}
        handleDisplayTitleInput={handleDisplayTitleInput}
        handleDurationChange={handleDurationChange}
        handleDurationInMonthsInput={handleDurationInMonthsInput}
        handleNameInput={handleNameInput}
        handleTextAreaInput={handleTextAreaInput}
        handleTierChange={handleTierChange}
        handleTrialAmountInput={handleTrialAmountInput}
        handleTypeChange={handleTypeChange}
        overrides={formState}
        selectedTier={selectedTier.tier}
        testId='add-offer-sidebar'
        tierOptions={tierCadenceOptions}
        typeOptions={typeOptions}
        validate={validate}
    />;

    const iframe = <PortalFrame
        href={href || ''}
        portalParent='offers'
    />;
    return <PreviewModalContent
        afterClose={() => {
            updateRoute('offers');
        }}
        backDropClick={false}
        cancelLabel='Cancel'
        deviceSelector={false}
        dirty={saveState === 'unsaved'}
        height='full'
        okColor={okProps.color}
        okLabel='Publish'
        preview={iframe}
        previewToolbar={false}
        sidebar={sidebar}
        size='lg'
        testId='add-offer-modal'
        title='Offer'
        width={1140}
        onCancel={cancelAddOffer}
        onOk={async () => {
            validate();
            const isErrorsEmpty = Object.values(errors).every(error => !error);
            if (!isErrorsEmpty) {
                toast.remove();
                showToast({
                    title: 'Can\'t save offer',
                    type: 'info',
                    message: 'Make sure you filled all required fields'
                });
                return;
            }

            try {
                if (await handleSave({force: true})) {
                    return;
                }
            } catch (e) {
                let message;

                if (e instanceof JSONError && e.data && e.data.errors[0]) {
                    message = e.data.errors[0].context || e.data.errors[0].message;
                }

                toast.remove();
                if (message) {
                    showToast({
                        title: 'Can\'t save offer',
                        type: 'error',
                        message: message || 'Please try again later'
                    });
                }
            }
        }}
    />;
};

export default AddOfferModal;
