import { isArray, isFunction } from 'lodash';
import { reactive, UnwrapRef, watch } from '@vue/composition-api';
import { CellValue, SyncWatchMass } from '@/lib/types';

export const parseWatcher = (config) => {
    const [watcher, cb] = config;
    const watchKeys = isArray(watcher) ? watcher : [watcher];
    return [watchKeys, cb];
};

export const buildWatchers = <T>(
    watchKeys: string[],
    dataWatcher: (key: string) => () => any,
    watchCb: Function,
    dataGetter: () => any,
    valueMass: SyncWatchMass<T>,
    inputHandler?: (value: T) => void,
    immediate = true,
) => {
    watchKeys.forEach((key) =>
        watch(
            dataWatcher(key),
            () => {
                valueMass.unused = false;
                valueMass.value = watchCb(dataGetter());
                inputHandler && inputHandler(valueMass.value);
            },
            { immediate },
        ),
    );
};

export const useWatchSyncValue = <T>(
    defaultValue: T,
    config:
        | undefined
        | [string | string[], (rowData: Record<string, CellValue>) => T]
        | ((rowData: Record<string, CellValue>) => T),
    dataWatcher: (key: string) => () => any,
    dataGetter: () => any,
    inputHandler?: (value: UnwrapRef<T>) => void,
    immediate = true,
) => {
    const valueMass = reactive({
        unused: true,
        value: defaultValue as T,
    });
    if (!config) {
        return valueMass;
    }
    if (isFunction(config)) {
        valueMass.unused = false;
        valueMass.value = config(dataGetter()) as UnwrapRef<T>;
    }
    if (isArray(config)) {
        const [watchKeys, cb] = parseWatcher(config);
        buildWatchers(watchKeys, dataWatcher, cb, dataGetter, valueMass, inputHandler, immediate);
    }
    return valueMass;
};