import { ElementRef, Injectable } from '@angular/core';
import { CropperPosition, Dimensions, MoveStart } from '../interfaces';
import { CropperSettings } from '../interfaces/cropper.settings';

@Injectable({ providedIn: 'root' })
export class CropperPositionService {
  resetCropperPosition(sourceImage: ElementRef, cropperPosition: CropperPosition, settings: CropperSettings, maxSize: Dimensions): void {
    if (!sourceImage?.nativeElement) {
      return;
    }
    if (settings.cropperStaticHeight && settings.cropperStaticWidth) {
      cropperPosition.x1 = 0;
      cropperPosition.x2 = maxSize.width > settings.cropperStaticWidth ? settings.cropperStaticWidth : maxSize.width;
      cropperPosition.y1 = 0;
      cropperPosition.y2 = maxSize.height > settings.cropperStaticHeight ? settings.cropperStaticHeight : maxSize.height;
    } else {
      const cropperWidth = Math.min(settings.cropperScaledMaxWidth, maxSize.width);
      const cropperHeight = Math.min(settings.cropperScaledMaxHeight, maxSize.height);
      if (!settings.maintainAspectRatio) {
        cropperPosition.x1 = 0;
        cropperPosition.x2 = cropperWidth;
        cropperPosition.y1 = 0;
        cropperPosition.y2 = cropperHeight;
      } else if (maxSize.width / settings.aspectRatio < maxSize.height) {
        cropperPosition.x1 = 0;
        cropperPosition.x2 = cropperWidth;
        const cropperHeightWithAspectRatio = cropperWidth / settings.aspectRatio;
        cropperPosition.y1 = (maxSize.height - cropperHeightWithAspectRatio) / 2;
        cropperPosition.y2 = cropperPosition.y1 + cropperHeightWithAspectRatio;
      } else {
        cropperPosition.y1 = 0;
        cropperPosition.y2 = cropperHeight;
        const cropperWidthWithAspectRatio = cropperHeight * settings.aspectRatio;
        cropperPosition.x1 = (maxSize.width - cropperWidthWithAspectRatio) / 2;
        cropperPosition.x2 = cropperPosition.x1 + cropperWidthWithAspectRatio;
      }
    }
  }

  move(event: Event, moveStart: MoveStart, cropperPosition: CropperPosition) {
    const diffX = this.getClientX(event) - moveStart.clientX;
    const diffY = this.getClientY(event) - moveStart.clientY;

    cropperPosition.x1 = moveStart.x1 + diffX;
    cropperPosition.y1 = moveStart.y1 + diffY;
    cropperPosition.x2 = moveStart.x2 + diffX;
    cropperPosition.y2 = moveStart.y2 + diffY;
  }

  resize(event: Event, moveStart: MoveStart, cropperPosition: CropperPosition, maxSize: Dimensions, settings: CropperSettings): void {
    const moveX = this.getClientX(event) - moveStart.clientX;
    const moveY = this.getClientY(event) - moveStart.clientY;
    switch (moveStart.position) {
      case 'left':
        cropperPosition.x1 = Math.min(
          Math.max(moveStart.x1 + moveX, cropperPosition.x2 - settings.cropperScaledMaxWidth),
          cropperPosition.x2 - settings.cropperScaledMinWidth
        );
        break;
      case 'topleft':
        cropperPosition.x1 = Math.min(
          Math.max(moveStart.x1 + moveX, cropperPosition.x2 - settings.cropperScaledMaxWidth),
          cropperPosition.x2 - settings.cropperScaledMinWidth
        );
        cropperPosition.y1 = Math.min(
          Math.max(moveStart.y1 + moveY, cropperPosition.y2 - settings.cropperScaledMaxHeight),
          cropperPosition.y2 - settings.cropperScaledMinHeight
        );
        break;
      case 'top':
        cropperPosition.y1 = Math.min(
          Math.max(moveStart.y1 + moveY, cropperPosition.y2 - settings.cropperScaledMaxHeight),
          cropperPosition.y2 - settings.cropperScaledMinHeight
        );
        break;
      case 'topright':
        cropperPosition.x2 = Math.max(
          Math.min(moveStart.x2 + moveX, cropperPosition.x1 + settings.cropperScaledMaxWidth),
          cropperPosition.x1 + settings.cropperScaledMinWidth
        );
        cropperPosition.y1 = Math.min(
          Math.max(moveStart.y1 + moveY, cropperPosition.y2 - settings.cropperScaledMaxHeight),
          cropperPosition.y2 - settings.cropperScaledMinHeight
        );
        break;
      case 'right':
        cropperPosition.x2 = Math.max(
          Math.min(moveStart.x2 + moveX, cropperPosition.x1 + settings.cropperScaledMaxWidth),
          cropperPosition.x1 + settings.cropperScaledMinWidth
        );
        break;
      case 'bottomright':
        cropperPosition.x2 = Math.max(
          Math.min(moveStart.x2 + moveX, cropperPosition.x1 + settings.cropperScaledMaxWidth),
          cropperPosition.x1 + settings.cropperScaledMinWidth
        );
        cropperPosition.y2 = Math.max(
          Math.min(moveStart.y2 + moveY, cropperPosition.y1 + settings.cropperScaledMaxHeight),
          cropperPosition.y1 + settings.cropperScaledMinHeight
        );
        break;
      case 'bottom':
        cropperPosition.y2 = Math.max(
          Math.min(moveStart.y2 + moveY, cropperPosition.y1 + settings.cropperScaledMaxHeight),
          cropperPosition.y1 + settings.cropperScaledMinHeight
        );
        break;
      case 'bottomleft':
        cropperPosition.x1 = Math.min(
          Math.max(moveStart.x1 + moveX, cropperPosition.x2 - settings.cropperScaledMaxWidth),
          cropperPosition.x2 - settings.cropperScaledMinWidth
        );
        cropperPosition.y2 = Math.max(
          Math.min(moveStart.y2 + moveY, cropperPosition.y1 + settings.cropperScaledMaxHeight),
          cropperPosition.y1 + settings.cropperScaledMinHeight
        );
        break;
      case 'center':
        {
          const newWidth = Math.min(
            Math.max(settings.cropperScaledMinWidth, Math.abs(moveStart.x2 - moveStart.x1)),
            settings.cropperScaledMaxWidth
          );
          const newHeight = Math.min(
            Math.max(settings.cropperScaledMinHeight, Math.abs(moveStart.y2 - moveStart.y1)),
            settings.cropperScaledMaxHeight
          );
          cropperPosition.x1 = moveStart.clientX - newWidth / 2;
          cropperPosition.x2 = moveStart.clientX + newWidth / 2;
          cropperPosition.y1 = moveStart.clientY - newHeight / 2;
          cropperPosition.y2 = moveStart.clientY + newHeight / 2;
          if (cropperPosition.x1 < 0) {
            cropperPosition.x2 -= cropperPosition.x1;
            cropperPosition.x1 = 0;
          } else if (cropperPosition.x2 > maxSize.width) {
            cropperPosition.x1 -= cropperPosition.x2 - maxSize.width;
            cropperPosition.x2 = maxSize.width;
          }
          if (cropperPosition.y1 < 0) {
            cropperPosition.y2 -= cropperPosition.y1;
            cropperPosition.y1 = 0;
          } else if (cropperPosition.y2 > maxSize.height) {
            cropperPosition.y1 -= cropperPosition.y2 - maxSize.height;
            cropperPosition.y2 = maxSize.height;
          }
        }
        break;
    }

    if (settings.maintainAspectRatio) {
      this.checkAspectRatio(moveStart.position!, cropperPosition, maxSize, settings);
    }
  }

  checkAspectRatio(position: string, cropperPosition: CropperPosition, maxSize: Dimensions, settings: CropperSettings): void {
    let overflowX = 0;
    let overflowY = 0;

    switch (position) {
      case 'top':
        cropperPosition.x2 = cropperPosition.x1 + (cropperPosition.y2 - cropperPosition.y1) * settings.aspectRatio;
        overflowX = Math.max(cropperPosition.x2 - maxSize.width, 0);
        overflowY = Math.max(0 - cropperPosition.y1, 0);
        if (overflowX > 0 || overflowY > 0) {
          cropperPosition.x2 -= overflowY * settings.aspectRatio > overflowX ? overflowY * settings.aspectRatio : overflowX;
          cropperPosition.y1 += overflowY * settings.aspectRatio > overflowX ? overflowY : overflowX / settings.aspectRatio;
        }
        break;
      case 'bottom':
        cropperPosition.x2 = cropperPosition.x1 + (cropperPosition.y2 - cropperPosition.y1) * settings.aspectRatio;
        overflowX = Math.max(cropperPosition.x2 - maxSize.width, 0);
        overflowY = Math.max(cropperPosition.y2 - maxSize.height, 0);
        if (overflowX > 0 || overflowY > 0) {
          cropperPosition.x2 -= overflowY * settings.aspectRatio > overflowX ? overflowY * settings.aspectRatio : overflowX;
          cropperPosition.y2 -= overflowY * settings.aspectRatio > overflowX ? overflowY : overflowX / settings.aspectRatio;
        }
        break;
      case 'topleft':
        cropperPosition.y1 = cropperPosition.y2 - (cropperPosition.x2 - cropperPosition.x1) / settings.aspectRatio;
        overflowX = Math.max(0 - cropperPosition.x1, 0);
        overflowY = Math.max(0 - cropperPosition.y1, 0);
        if (overflowX > 0 || overflowY > 0) {
          cropperPosition.x1 += overflowY * settings.aspectRatio > overflowX ? overflowY * settings.aspectRatio : overflowX;
          cropperPosition.y1 += overflowY * settings.aspectRatio > overflowX ? overflowY : overflowX / settings.aspectRatio;
        }
        break;
      case 'topright':
        cropperPosition.y1 = cropperPosition.y2 - (cropperPosition.x2 - cropperPosition.x1) / settings.aspectRatio;
        overflowX = Math.max(cropperPosition.x2 - maxSize.width, 0);
        overflowY = Math.max(0 - cropperPosition.y1, 0);
        if (overflowX > 0 || overflowY > 0) {
          cropperPosition.x2 -= overflowY * settings.aspectRatio > overflowX ? overflowY * settings.aspectRatio : overflowX;
          cropperPosition.y1 += overflowY * settings.aspectRatio > overflowX ? overflowY : overflowX / settings.aspectRatio;
        }
        break;
      case 'right':
      case 'bottomright':
        cropperPosition.y2 = cropperPosition.y1 + (cropperPosition.x2 - cropperPosition.x1) / settings.aspectRatio;
        overflowX = Math.max(cropperPosition.x2 - maxSize.width, 0);
        overflowY = Math.max(cropperPosition.y2 - maxSize.height, 0);
        if (overflowX > 0 || overflowY > 0) {
          cropperPosition.x2 -= overflowY * settings.aspectRatio > overflowX ? overflowY * settings.aspectRatio : overflowX;
          cropperPosition.y2 -= overflowY * settings.aspectRatio > overflowX ? overflowY : overflowX / settings.aspectRatio;
        }
        break;
      case 'left':
      case 'bottomleft':
        cropperPosition.y2 = cropperPosition.y1 + (cropperPosition.x2 - cropperPosition.x1) / settings.aspectRatio;
        overflowX = Math.max(0 - cropperPosition.x1, 0);
        overflowY = Math.max(cropperPosition.y2 - maxSize.height, 0);
        if (overflowX > 0 || overflowY > 0) {
          cropperPosition.x1 += overflowY * settings.aspectRatio > overflowX ? overflowY * settings.aspectRatio : overflowX;
          cropperPosition.y2 -= overflowY * settings.aspectRatio > overflowX ? overflowY : overflowX / settings.aspectRatio;
        }
        break;
      case 'center':
        {
          cropperPosition.x2 = cropperPosition.x1 + (cropperPosition.y2 - cropperPosition.y1) * settings.aspectRatio;
          cropperPosition.y2 = cropperPosition.y1 + (cropperPosition.x2 - cropperPosition.x1) / settings.aspectRatio;
          const overflowX1 = Math.max(0 - cropperPosition.x1, 0);
          const overflowX2 = Math.max(cropperPosition.x2 - maxSize.width, 0);
          const overflowY1 = Math.max(cropperPosition.y2 - maxSize.height, 0);
          const overflowY2 = Math.max(0 - cropperPosition.y1, 0);
          if (overflowX1 > 0 || overflowX2 > 0 || overflowY1 > 0 || overflowY2 > 0) {
            cropperPosition.x1 += overflowY1 * settings.aspectRatio > overflowX1 ? overflowY1 * settings.aspectRatio : overflowX1;
            cropperPosition.x2 -= overflowY2 * settings.aspectRatio > overflowX2 ? overflowY2 * settings.aspectRatio : overflowX2;
            cropperPosition.y1 += overflowY2 * settings.aspectRatio > overflowX2 ? overflowY2 : overflowX2 / settings.aspectRatio;
            cropperPosition.y2 -= overflowY1 * settings.aspectRatio > overflowX1 ? overflowY1 : overflowX1 / settings.aspectRatio;
          }
        }
        break;
    }
  }

  // eslint-disable-next-line
  getClientX(event: any): number {
    return event.touches?.[0].clientX || event.clientX || 0;
  }

  // eslint-disable-next-line
  getClientY(event: any): number {
    return event.touches?.[0].clientY || event.clientY || 0;
  }
}