import { useEffect, useRef, useState } from 'react';
import { autorun } from 'mobx';

import { IdType, InMemoryDataSource, Preprocessors } from '@servicetitan/data-query';
import { useInitializedRef } from '@servicetitan/react-hooks';
import { TableState, TableStateConstructorParams } from '../table-state';
//

export enum ResetPaginationMode {
    Never,
    OnUpdateDataRoot,
    Always,
}

export interface DatasourceOptions<T, TID extends IdType = any> {
    idSelector: (row: T) => TID;
    datasourcePreprocessors?: Preprocessors<T>;
}

export const useObservingTableState = <
    T,
    TID extends IdType = any,
    P = never,
    PID extends IdType = never,
>(
    data: T[],
    tableArgs: TableStateConstructorParams<T, TID, P, PID>,
    datasourceOptions: DatasourceOptions<T, TID>,
    resetPagination: ResetPaginationMode = ResetPaginationMode.OnUpdateDataRoot
): TableState<T, TID, P, PID> => {
    const tableStateRef = useInitializedRef(() => new TableState<T, TID, P, PID>(tableArgs));
    const datasourceDataRef = useRef<T[]>();
    const tableStateDataRef = useRef<T[]>();
    const [dataSource, setDataSource] = useState<InMemoryDataSource<T, TID>>();

    useEffect(() => {
        const disposer = autorun(() => {
            setDataSource(
                new InMemoryDataSource(
                    data,
                    datasourceOptions.idSelector,
                    datasourceOptions.datasourcePreprocessors
                )
            );
            datasourceDataRef.current = data;
        });
        return () => disposer();
        // eslint-disable-next-line react-hooks/exhaustive-deps
    }, [data]);

    useEffect(() => {
        if (dataSource) {
            if (
                tableStateRef.current.skip >= (datasourceDataRef.current?.length ?? 0) ||
                resetPagination === ResetPaginationMode.Always ||
                (resetPagination === ResetPaginationMode.OnUpdateDataRoot &&
                    tableStateDataRef.current !== datasourceDataRef.current)
            ) {
                tableStateRef.current.setDataSource(dataSource);
            } else {
                const state = tableStateRef.current.exportState();
                tableStateRef.current.setDataSource(dataSource, { initialState: state });
            }
            tableStateDataRef.current = datasourceDataRef.current;
        }
    }, [dataSource, resetPagination, tableStateRef]);

    return tableStateRef.current;
};