import type { IActivityHandler } from "@vertigis/workflow";
import { lineString, lineSliceAlong, length } from "@turf/turf";

/** An interface that defines the inputs of the activity. */
interface SliceLineInputs {
  /**
   * @displayName Path
   * @description an array of path coordinates.
   * @required
   */
  path: [];

  /**
   * @displayName start
   * @description start distance to slice
   * @required
   */
  start: number;

  /**
   * @displayName end
   * @description end distance to slice
   * @required
   */
  end: number;
}

/** An interface that defines the outputs of the activity. */
interface SliceLineOutputs {
  /**
   * @description The result of the activity.
   */
  result: object;
}

function sliceLine(path: [], start: number, stop: number) {
  const line = lineString(path);
  const linelength = length(line, { units: "meters" });

  if (stop > linelength) {
    stop = linelength;
  }

  const sliced = lineSliceAlong(line, start, stop, { units: "meters" });
  return sliced;
}

/**
 * @displayName Slice Line
 * @category Geocortex
 * @description Slice Line based on start and end distance - Ver 1.01
 */
export default class SliceLineActivity implements IActivityHandler {
  /** Perform the execution logic of the activity. */
  execute(inputs: SliceLineInputs): SliceLineOutputs {
    const result = sliceLine(inputs.path, inputs.start, inputs.end);
    return {
      result: result,
    };
  }
}