import React, { useMemo, useState, useCallback } from 'react';
import PanningContext, {
  PanningContextState,
  PanAmountDirections,
  PanLocationProps,
  PanningDirectionsEnum,
} from './PanningContext';

/**
 * 包装 panResponderView 和 panListenerView 共享一个 context
 */
const PanningProvider = ({ children }: { children: React.ReactNode }): JSX.Element => {
  const [isPanning, setIspanning] = useState(false);
  const [wasTerminated, setWasTerminated] = useState(false);
  const [panLocation, setPanLocation] = useState<PanLocationProps>({});
  const [amountDirections, setAmountDirections] = useState<PanAmountDirections>({
    dragDirections: {},
    dragDeltas: {},
    swipeDirections: {},
    swipeVelocities: {},
  });

  const onPanStart = useCallback(() => {
    setIspanning(true);
    setWasTerminated(false);
  }, []);

  const onPanRelease = useCallback(() => {
    setIspanning(false);
  }, []);

  const onPanTerminated = useCallback(() => {
    setIspanning(false);
    setWasTerminated(true);
  }, []);

  const onDrag = useCallback<PanningContextState['onDrag']>(({ directions, deltas }) => {
    setAmountDirections({
      dragDirections: directions,
      dragDeltas: deltas,
      swipeDirections: {},
      swipeVelocities: {},
    });
  }, []);

  const onSwipe = useCallback<PanningContextState['onSwipe']>(({ directions, velocities }) => {
    setAmountDirections({
      swipeDirections: directions,
      swipeVelocities: velocities,
      dragDirections: {},
      dragDeltas: {},
    });
  }, []);

  const onPanLocationChanged = useCallback<PanningContextState['onPanLocationChanged']>(
    location => {
      setPanLocation(location);
    },
    []
  );

  const contextValue = useMemo<PanningContextState>(
    () => ({
      ...amountDirections,
      isPanning,
      panLocation,
      wasTerminated,
      onPanRelease,
      onPanStart,
      onPanTerminated,
      onDrag,
      onSwipe,
      onPanLocationChanged,
    }),
    [
      isPanning,
      panLocation,
      onPanRelease,
      wasTerminated,
      onPanStart,
      onPanTerminated,
      amountDirections,
      onDrag,
      onSwipe,
      onPanLocationChanged,
    ]
  );

  return <PanningContext.Provider value={contextValue}>{children}</PanningContext.Provider>;
};

PanningProvider.Directions = PanningDirectionsEnum;

export default PanningProvider;