/**
 * DumpInventoryState - Dump inventory into nearby containers
 * Keeps fuel items, dumps everything else.
 * 
 * Improvements over v1:
 * - Uses Levenshtein distance for fuzzy container name matching
 * - Detects containers via peripheral inspection on all sides
 * - Tracks dump success/failure per direction
 * - Reports detailed dump stats
 * - Optionally navigates home before dumping
 */
import { BaseState } from './BaseState.js';
import { findBestMatch } from '../helpers/levenshtein.js';

// Items to keep (fuel sources and tools)
const KEEP_ITEMS = new Set([
  'minecraft:coal', 'minecraft:charcoal', 'minecraft:coal_block',
  'minecraft:torch', 'minecraft:lava_bucket',
]);

// Known container block names (used for fuzzy matching)
const CONTAINER_NAMES = [
  'chest', 'barrel', 'shulker_box', 'hopper', 'dropper', 'dispenser',
  'trapped_chest', 'ender_chest', 'furnace', 'blast_furnace', 'smoker',
];

/**
 * Check if a block name is likely a container using fuzzy matching
 */
function isContainerBlock(blockName) {
  if (!blockName) return false;
  const shortName = blockName.replace(/^[^:]+:/, '').toLowerCase();
  
  // Exact substring match first
  for (const container of CONTAINER_NAMES) {
    if (shortName.includes(container)) return true;
  }
  
  // Fuzzy match as fallback
  const { match, distance } = findBestMatch(shortName, CONTAINER_NAMES, 3);
  return match !== null && distance <= 2;
}

export class DumpInventoryState extends BaseState {
  constructor(turtle, data = {}) {
    super(turtle, data);
    this.returnState = data.returnState || null;
    this.returnData = data.returnData || {};
    this.navigateHome = data.navigateHome || false;
    this.keepItems = data.keepItems
      ? new Set([...KEEP_ITEMS, ...data.keepItems])
      : KEEP_ITEMS;
  }

  get name() {
    return 'dumping';
  }

  get description() {
    return this.navigateHome ? 'Returning home to dump inventory' : 'Dumping inventory';
  }

  async *act() {
    console.log(`[${this.turtle.id}] Starting inventory dump`);

    // Optionally navigate home first
    if (this.navigateHome && this.turtle.homePosition) {
      console.log(`[${this.turtle.id}] Navigating home before dumping`);
      yield* this.navigateTo(this.turtle.homePosition);
      yield;
    }

    // First, detect containers by inspecting all directions
    const containerDirections = await this._detectContainers();
    
    if (containerDirections.length === 0) {
      console.log(`[${this.turtle.id}] No containers found nearby, trying blind dump`);
      containerDirections.push('front', 'up', 'down');
    } else {
      console.log(`[${this.turtle.id}] Found containers: ${containerDirections.join(', ')}`);
    }

    // Build keep items set for Lua
    const keepItemsList = [...this.keepItems].map(n => `"${n}"`).join(', ');

    // Map direction names to Lua drop functions
    const dropFnMap = {
      front: 'turtle.drop',
      up: 'turtle.dropUp',
      down: 'turtle.dropDown',
    };

    // Build the drop functions array for only detected container directions
    const dropFnEntries = containerDirections
      .filter(d => dropFnMap[d])
      .map(d => dropFnMap[d]);

    if (dropFnEntries.length === 0) {
      console.log(`[${this.turtle.id}] No valid drop directions`);
      this._transitionOut();
      return;
    }
    
    const result = await this.exec(`
      local keepItems = {${keepItemsList}}
      local keepSet = {}
      for _, name in ipairs(keepItems) do keepSet[name] = true end
      
      local dropFns = {${dropFnEntries.join(', ')}}
      
      local dumpedCount = 0
      local failedCount = 0
      
      for _, dropFn in ipairs(dropFns) do
        for slot = 1, 16 do
          local item = turtle.getItemDetail(slot)
          if item and not keepSet[item.name] then
            turtle.select(slot)
            local prevCount = item.count
            if dropFn() then
              local remaining = turtle.getItemCount(slot)
              dumpedCount = dumpedCount + (prevCount - remaining)
            else
              failedCount = failedCount + 1
            end
          end
        end
      end
      
      turtle.select(1)
      return {dumped = dumpedCount, failed = failedCount}
    `);

    if (result) {
      console.log(`[${this.turtle.id}] Dumped ${result.dumped} items (${result.failed} drops failed)`);
      if (result.failed > 0) {
        this.turtle.warning = `Dump: ${result.failed} drops failed (container full?)`;
      }
    }

    yield;

    // Update inventory after dumping
    await this.getInventory();

    // Refresh any adjacent inventory peripherals
    for (const dir of containerDirections) {
      if (this.turtle._peripherals?.[dir]?.types?.includes('inventory')) {
        try {
          await this.turtle.connectToInventory(dir);
        } catch (e) { /* ignore */ }
      }
    }

    this._transitionOut();
  }

  /**
   * Detect which directions have containers by inspecting blocks
   */
  async _detectContainers() {
    const result = await this.exec(`
      local dirs = {}
      local h, d
      h, d = turtle.inspect()
      if h then dirs.front = d.name end
      h, d = turtle.inspectUp()
      if h then dirs.up = d.name end
      h, d = turtle.inspectDown()
      if h then dirs.down = d.name end
      return dirs
    `);

    if (!result || typeof result !== 'object') return [];

    const containerDirs = [];
    for (const [dir, blockName] of Object.entries(result)) {
      if (isContainerBlock(blockName)) {
        containerDirs.push(dir);
      }
    }
    return containerDirs;
  }

  /**
   * Transition to the next state (return state or idle)
   */
  _transitionOut() {
    if (this.returnState) {
      this.turtle.setState(this.returnState, this.returnData);
    } else {
      this.turtle.setState('idle');
    }
  }

  getRecoveryData() {
    return {
      ...super.getRecoveryData(),
      data: {
        returnState: this.returnState,
        returnData: this.returnData,
        navigateHome: this.navigateHome,
        keepItems: this.keepItems !== KEEP_ITEMS
          ? [...this.keepItems].filter(i => !KEEP_ITEMS.has(i))
          : undefined,
      },
    };
  }
}