import { logger } from '../util/logger.js';
import type { OcrDaemon, GridItem, GridMatch } from './OcrDaemon.js';
import type { Region } from '../types.js';

// ── Grid type definitions ───────────────────────────────────────────────────

export interface GridLayout {
  region: Region;
  cols: number;
  rows: number;
}

export interface CellCoord {
  row: number;
  col: number;
  x: number;
  y: number;
}

export interface ScanResult {
  layout: GridLayout;
  occupied: CellCoord[];
  items: GridItem[];
  matches?: GridMatch[];
}

// ── Calibrated grid layouts (2560×1440) ─────────────────────────────────────

export const GRID_LAYOUTS: Record<string, GridLayout> = {
  /** Player inventory — always 12×5, right side (below equipment slots) */
  inventory: {
    region: { x: 1696, y: 788, width: 840, height: 350 },
    cols: 12,
    rows: 5,
  },
  /** Personal stash 12×12 — left side, tab not in folder */
  stash12: {
    region: { x: 23, y: 169, width: 840, height: 840 },
    cols: 12,
    rows: 12,
  },
  /** Personal stash 12×12 — left side, tab in folder */
  stash12_folder: {
    region: { x: 23, y: 216, width: 840, height: 840 },
    cols: 12,
    rows: 12,
  },
  /** Personal stash 24×24 (quad tab) — left side, tab not in folder */
  stash24: {
    region: { x: 23, y: 169, width: 840, height: 840 },
    cols: 24,
    rows: 24,
  },
  /** Personal stash 24×24 (quad tab) — left side, tab in folder */
  stash24_folder: {
    region: { x: 23, y: 216, width: 840, height: 840 },
    cols: 24,
    rows: 24,
  },
  /** Seller's public stash — always 12×12 */
  seller: {
    region: { x: 416, y: 299, width: 840, height: 840 },
    cols: 12,
    rows: 12,
  },
  /** NPC shop — 12×12 */
  shop: {
    region: { x: 23, y: 216, width: 840, height: 840 },
    cols: 12,
    rows: 12,
  },
  /** NPC vendor inventory — 12×12 */
  vendor: {
    region: { x: 416, y: 369, width: 840, height: 840 },
    cols: 12,
    rows: 12,
  },
};

// Backward-compat exports
export const INVENTORY = GRID_LAYOUTS.inventory;
export const STASH_12x12 = GRID_LAYOUTS.stash12;
export const STASH_24x24 = GRID_LAYOUTS.stash24;
export const SELLER_12x12 = GRID_LAYOUTS.seller;

// ── GridReader ──────────────────────────────────────────────────────────────

export class GridReader {
  constructor(private daemon: OcrDaemon) {}

  /**
   * Scan a named grid layout for occupied cells.
   */
  async scan(layoutName: string, threshold?: number, targetRow?: number, targetCol?: number): Promise<ScanResult> {
    const layout = GRID_LAYOUTS[layoutName];
    if (!layout) throw new Error(`Unknown grid layout: ${layoutName}`);

    const t = performance.now();
    const { occupied, items, matches } = await this.getOccupiedCells(layout, threshold, targetRow, targetCol);

    const ms = (performance.now() - t).toFixed(0);
    logger.info(
      { layoutName, cols: layout.cols, rows: layout.rows, occupied: occupied.length, items: items.length, matches: matches?.length, ms },
      'Grid scan complete',
    );

    return { layout, occupied, items, matches };
  }

  /** Get the screen-space center of a grid cell */
  getCellCenter(layout: GridLayout, row: number, col: number): { x: number; y: number } {
    const cellW = layout.region.width / layout.cols;
    const cellH = layout.region.height / layout.rows;
    return {
      x: Math.round(layout.region.x + col * cellW + cellW / 2),
      y: Math.round(layout.region.y + row * cellH + cellH / 2),
    };
  }

  /** Scan the grid and return which cells are occupied and detected items */
  async getOccupiedCells(layout: GridLayout, threshold?: number, targetRow?: number, targetCol?: number): Promise<{ occupied: CellCoord[]; items: GridItem[]; matches?: GridMatch[] }> {
    const t = performance.now();
    const result = await this.daemon.gridScan(
      layout.region,
      layout.cols,
      layout.rows,
      threshold,
      targetRow,
      targetCol,
    );

    const occupied: CellCoord[] = [];
    for (let row = 0; row < result.cells.length; row++) {
      for (let col = 0; col < result.cells[row].length; col++) {
        if (result.cells[row][col]) {
          const center = this.getCellCenter(layout, row, col);
          occupied.push({ row, col, x: center.x, y: center.y });
        }
      }
    }

    const ms = (performance.now() - t).toFixed(0);
    logger.info(
      { layout: `${layout.cols}x${layout.rows}`, occupied: occupied.length, items: result.items.length, matches: result.matches?.length, ms },
      'Grid scan complete',
    );
    return { occupied, items: result.items, matches: result.matches };
  }

  /** Get all cell centers in the grid */
  getAllCells(layout: GridLayout): CellCoord[] {
    const cells: CellCoord[] = [];
    for (let row = 0; row < layout.rows; row++) {
      for (let col = 0; col < layout.cols; col++) {
        const center = this.getCellCenter(layout, row, col);
        cells.push({ row, col, x: center.x, y: center.y });
      }
    }
    return cells;
  }
}