import {
  PRODUCTIVITY_RECOVERY_RATE, PRODUCTIVITY_THRESHOLD,
  type Needs, type Movement, type NPCBrain, type Position,
} from '@dflike/shared';
import type { World } from '../ecs/World.js';
import type { GameMap } from '../map/GameMap.js';
import { getEffectiveStat } from './statHelpers.js';
import { addItem } from '../industry/inventoryHelpers.js';
import { industryConfig } from '../config/industryConfig.js';

export interface GatheringState {
  resourceType: string;
  ticksRemaining: number;
}

export function gatheringSystem(world: World, map: GameMap): void {
  for (const entity of world.query('npcBrain', 'position', 'needs', 'movement')) {
    const brain = world.getComponent<NPCBrain>(entity, 'npcBrain')!;

    if (brain.currentGoal !== 'gather') continue;

    const pos = world.getComponent<Position>(entity, 'position')!;
    const needs = world.getComponent<Needs>(entity, 'needs')!;
    const movement = world.getComponent<Movement>(entity, 'movement')!;
    const gs = world.getComponent<GatheringState>(entity, 'gatheringState');

    // Already gathering — tick down
    if (gs) {
      gs.ticksRemaining--;
      needs.productivity = Math.min(100, needs.productivity + PRODUCTIVITY_RECOVERY_RATE);

      if (gs.ticksRemaining <= 0) {
        // Complete: add resource to inventory
        const inv = world.getComponent<Map<string, number>>(entity, 'inventory');
        if (inv) {
          addItem(inv, gs.resourceType, industryConfig.gatherYield);
        }
        world.removeComponent(entity, 'gatheringState');

        // Decide next action
        if (needs.productivity >= PRODUCTIVITY_THRESHOLD) {
          brain.currentGoal = 'wander';
        }
        // else brain stays on 'gather', npcBrain will pick new target next tick
      }
      continue;
    }

    // Not yet gathering — check if at resource tile and idle
    if (movement.state !== 'idle') continue;

    const resourceTile = map.resourceTiles.find(r => r.x === pos.x && r.y === pos.y);
    if (!resourceTile) continue;

    // Start gathering
    const str = getEffectiveStat(world, entity, 'strength');
    const baseTicks = industryConfig.gatherBaseTicks;
    const ticks = Math.max(1, Math.round(baseTicks * (1 - (str - 10) * industryConfig.gatherStrengthModifier)));

    world.addComponent<GatheringState>(entity, 'gatheringState', {
      resourceType: resourceTile.resourceType,
      ticksRemaining: ticks,
    });

    // Recover productivity on first tick too
    needs.productivity = Math.min(100, needs.productivity + PRODUCTIVITY_RECOVERY_RATE);
  }
}