import {Container} from '@pixi/react';
import {useEffect, useState} from 'react';

import {RESOLUTION} from '@/constants.js';
import {usePacket} from '@/context/client.js';
import {useEcs, useEcsTick} from '@/context/ecs.js';
import {useMainEntity} from '@/context/main-entity.js';

import Entities from './entities.jsx';
import TargetingGhost from './targeting-ghost.jsx';
import TargetingGrid from './targeting-grid.jsx';
import TileLayer from './tile-layer.jsx';
import Water from './water.jsx';

const NIGHTNESS = 0.1;

function calculateDarkness(hour) {
  let darkness = 0;
  if (hour >= 21 || hour < 4) {
    darkness = 0.8;
  }
  if (hour >= 4 && hour < 7) {
    darkness = 0.8 * ((7 - hour) / 3);
  }
  if (hour >= 18 && hour < 21) {
    darkness = 0.8 * ((3 - (21 - hour)) / 3);
  }
  return Math.floor(darkness * 1000) / 1000;
}

export default function Ecs({scale}) {
  const [ecs] = useEcs();
  const [entities, setEntities] = useState({});
  const [mainEntity] = useMainEntity();
  const [hour, setHour] = useState(10);
  const [night, setNight] = useState();
  useEffect(() => {
    async function buildNightFilter() {
      const {ColorMatrixFilter} = await import('@pixi/filter-color-matrix');
      class NightFilter extends ColorMatrixFilter {
        setIntensity(intensity) {
          const double = NIGHTNESS * 2;
          const half = NIGHTNESS / 2;
          const redDown = 1 - (intensity * (1 + double));
          const blueUp = 1 - (intensity * (1 - half));
          const scale = intensity * NIGHTNESS;
          this.uniforms.m = [
            redDown, -scale, 0, 0, 0,
            -scale, (1 - intensity), scale, 0, 0,
            0, scale, blueUp, 0, 0,
            0, 0, 0, 1, 0,
          ];
        }
      }
      setNight(new NightFilter());
    }
    buildNightFilter();
  }, []);
  useEffect(() => {
    if (night) {
      night.setIntensity(calculateDarkness(hour));
    }
  }, [hour, night]);
  usePacket('EcsChange', async () => {
    setEntities({});
  }, [setEntities]);
  useEcsTick((payload) => {
    if (!ecs) {
      return;
    }
    const updatedEntities = {...entities};
    for (const id in payload) {
      const update = payload[id];
      if (false === update) {
        delete updatedEntities[id];
      }
      else {
        if ('1' === id) {
          if (update.Time) {
            setHour(Math.round(ecs.get(1).Time.hour * 60) / 60);
          }
        }
        updatedEntities[id] = ecs.get(id);
        if (update.Emitter?.emit) {
          updatedEntities[id].Emitter.emitting = {
            ...updatedEntities[id].Emitter.emitting,
            ...update.Emitter.emit,
          };
        }
      }
    }
    setEntities(updatedEntities);
  }, [ecs, entities, mainEntity]);
  if (!ecs || !mainEntity) {
    return false;
  }
  const entity = ecs.get(mainEntity);
  if (!entity) {
    return false;
  }
  const {Direction, Position, Wielder} = entity;
  const projected = Wielder.activeItem()?.project(Position.tile, Direction.direction)
  const {Camera} = entity;
  const {TileLayers: {layers: [layer]}, Water: WaterEcs} = ecs.get(1);
  const filters = [];
  if (night) {
    filters.push(night);
  }
  const [cx, cy] = [
    Math.round((Camera.x * scale) - RESOLUTION.x / 2),
    Math.round((Camera.y * scale) - RESOLUTION.y / 2),
  ];
  return (
    <Container
      filters={filters}
      scale={scale}
      x={-cx}
      y={-cy}
    >
      <TileLayer tileLayer={layer} />
      {WaterEcs && (
        <Water tileLayer={layer} water={WaterEcs.water} />
      )}
      {projected && (
        <TargetingGrid
          tileLayer={layer}
          x={Position.x}
          y={Position.y}
        />
      )}
      <Entities entities={entities} />
      {projected?.length > 0 && (
        <TargetingGhost
          projected={projected}
          tileLayer={layer}
        />
      )}
    </Container>
  )
}