import * as React from 'react';
import {
    Children,
    cloneElement,
    MouseEvent,
    MouseEventHandler,
    isValidElement,
    ReactElement,
    ReactNode,
    useMemo,
} from 'react';
import { Typography } from '@material-ui/core';
import classNames from 'classnames';
import { Record } from 'ra-core';

import { ClassesOverride } from '../../types';
import FormInput from '../../form/FormInput';
import { useSimpleFormIteratorStyles } from './useSimpleFormIteratorStyles';
import { useSimpleFormIterator } from './useSimpleFormIterator';
import { ArrayInputContextValue } from './ArrayInputContext';
import {
    SimpleFormIteratorItemContext,
    SimpleFormIteratorItemContextValue,
} from './SimpleFormIteratorItemContext';

export const SimpleFormIteratorItem = React.forwardRef(
    (props: SimpleFormIteratorItemProps, ref: any) => {
        const {
            basePath,
            children,
            classes,
            disabled,
            disableReordering,
            disableRemove,
            getItemLabel,
            index,
            margin,
            member,
            record,
            removeButton,
            reOrderButtons,
            resource,
            source,
            variant,
        } = props;

        const { total, reOrder, remove } = useSimpleFormIterator();
        // Returns a boolean to indicate whether to disable the remove button for certain fields.
        // If disableRemove is a function, then call the function with the current record to
        // determining if the button should be disabled. Otherwise, use a boolean property that
        // enables or disables the button for all of the fields.
        const disableRemoveField = (record: Record) => {
            if (typeof disableRemove === 'boolean') {
                return disableRemove;
            }
            return disableRemove && disableRemove(record);
        };

        // remove field and call the onClick event of the button passed as removeButton prop
        const handleRemoveButtonClick = (
            originalOnClickHandler: MouseEventHandler,
            index: number
        ) => (event: MouseEvent) => {
            remove(index);
            if (originalOnClickHandler) {
                originalOnClickHandler(event);
            }
        };

        const context = useMemo<SimpleFormIteratorItemContextValue>(
            () => ({
                index,
                total,
                reOrder: newIndex => reOrder(index, newIndex),
                remove: () => remove(index),
            }),
            [index, total, reOrder, remove]
        );

        return (
            <SimpleFormIteratorItemContext.Provider value={context}>
                <li className={classes.line} ref={ref}>
                    <div>
                        <div className={classes.indexContainer}>
                            <Typography
                                variant="body1"
                                className={classes.index}
                            >
                                {getItemLabel(index)}
                            </Typography>
                            {!disabled &&
                                !disableReordering &&
                                cloneElement(reOrderButtons, {
                                    index,
                                    max: total,
                                    reOrder,
                                    className: classNames(
                                        'button-reorder',
                                        `button-reorder-${source}-${index}`
                                    ),
                                })}
                        </div>
                    </div>
                    <section className={classes.form}>
                        {Children.map(
                            children,
                            (input: ReactElement, index2) => {
                                if (!isValidElement<any>(input)) {
                                    return null;
                                }
                                const { source, ...inputProps } = input.props;
                                return (
                                    <FormInput
                                        basePath={
                                            input.props.basePath || basePath
                                        }
                                        input={cloneElement(input, {
                                            source: source
                                                ? `${member}.${source}`
                                                : member,
                                            index: source ? undefined : index2,
                                            label:
                                                typeof input.props.label ===
                                                'undefined'
                                                    ? source
                                                        ? `resources.${resource}.fields.${source}`
                                                        : undefined
                                                    : input.props.label,
                                            disabled,
                                            ...inputProps,
                                        })}
                                        record={record}
                                        resource={resource}
                                        variant={variant}
                                        margin={margin}
                                    />
                                );
                            }
                        )}
                    </section>
                    {!disabled && !disableRemoveField(record) && (
                        <span className={classes.action}>
                            {cloneElement(removeButton, {
                                onClick: handleRemoveButtonClick(
                                    removeButton.props.onClick,
                                    index
                                ),
                                className: classNames(
                                    'button-remove',
                                    `button-remove-${source}-${index}`
                                ),
                            })}
                        </span>
                    )}
                </li>
            </SimpleFormIteratorItemContext.Provider>
        );
    }
);

export type DisableRemoveFunction = (record: Record) => boolean;

export type SimpleFormIteratorItemProps = ArrayInputContextValue & {
    basePath: string;
    children?: ReactNode;
    classes?: ClassesOverride<typeof useSimpleFormIteratorStyles>;
    disabled?: boolean;
    disableRemove?: boolean | DisableRemoveFunction;
    disableReordering?: boolean;
    getItemLabel?: (index: number) => string;
    index: number;
    margin?: 'none' | 'normal' | 'dense';
    member: string;
    onRemoveField: (index: number) => void;
    onReorder: (origin: number, destination: number) => void;
    record: Record;
    removeButton?: ReactElement;
    reOrderButtons?: ReactElement;
    resource: string;
    source: string;
    variant?: 'standard' | 'outlined' | 'filled';
};