import Spreadsheet from "../main";

export type ViewportConstructorProps = {
  top: number;
  left: number;
  right: number;
  bottom: number;
};

export class Viewport {
  root: Spreadsheet;

  top: number;
  left: number;
  right: number;
  bottom: number;

  firstRow: number;
  lastRow: number;
  firstCol: number;
  lastCol: number;

  constructor(root: Spreadsheet, props: ViewportConstructorProps) {
    this.root = root;

    this.top = props.top;
    this.left = props.left;
    this.right = props.right;
    this.bottom = props.bottom;

    this.firstRow = this.getFirstRow();
    this.lastCol = this.getFirstRow(); //!Temp
    this.firstCol = this.getFirstRow(); //!Temp
    this.lastRow = this.getLastRow();

    this.updateValues({
      top: 0,
      left: 0,
      right: this.root.viewProps.width,
      bottom: this.root.viewProps.height,
    });
  }

  updateValues(props: ViewportConstructorProps) {
    this.top = props.top;
    this.left = props.left;
    this.right = props.right;
    this.bottom = props.bottom;

    this.firstRow = this.getFirstRow();
    this.lastRow = this.getLastRow();
    this.firstCol = this.getFirstCol();
    this.lastCol = this.getLastCol();
  }

  /** Get index of first row in viewport */
  private getFirstRow(): number {
    const rowIdx = this.root.cache.getRowByYCoord(this.top);
    return rowIdx;
  }

  private getLastRow(): number {
    const rowIdx = this.root.cache.getRowByYCoord(this.bottom);
    return rowIdx;
  }

  private getFirstCol(): number {
    const colIdx = this.root.cache.getColumnByXCoord(this.left);

    return colIdx;
  }

  private getLastCol(): number {
    const colIdx = this.root.cache.getColumnByXCoord(this.right);

    return colIdx;
  }
}