#pragma once

/**
 * @file     	IHumanWarper.h
 * @brief    	Image warping base on Human detection
 * @copyright	VisionLabs LLC
 * @date     	17.11.2019
 * */

#include <fsdk/FSDKError.h>
#include <fsdk/IRefCounted.h>
#include <fsdk/Types/Detection.h>
#include <fsdk/Types/Image.h>
#include <fsdk/Types/Span.h>

namespace fsdk {

#ifndef DOXYGEN_SHOULD_SKIP_THIS
	DECLARE_SMARTPTR(IHumanWarper);
#endif
	
	/**
	 * @brief Human detection area warper interface.
	 * @details Performs cropping and resizing of an image for human descriptor extraction.
	 * */
	struct IHumanWarper : IRefCounted {
		/**
		 * @brief Warp human detection.
		 * @param [in] image source image.
		 * @param [in] detection detection coordinates in image space.
		 * @param [in/out] transformedImage warped image output.
		 * @note if transformedImage has the same width, height, format
		 * as the standard human warp and the same memory residence as source image has,
		 * then output data will be just copied to transformedImage without any memory allocation.
		 * New image will be allocated otherwise.
		 * @return Result with error code.
		 * @see Image, Detection, Result and FSDKError for details.
		 * @note image format must be R8G8B8, @see Format.
		 * */
		virtual Result<FSDKError>
		warp(
			const Image image,
			const Detection& detection,
			Image& transformedImage) const noexcept = 0;

		/**
		 * @brief Warps humans on multiple images.
		 * @param [in] images span of source images.
		 * @param [in] detections span of detection coordinates in corresponding source images space.
		 * @param [in/out] transformedImages span of input/output images where
		 * result will be stored.
		 * @note each detection in detections span corresponds to an image where this detection
		 * was taken from by the same index(i.e detections[i] <--> images[i]), therefore, if there are 
		 * multiple detections on the same image user must duplicate those images in order for the first
		 * statement to hold true.
		 * @note if output images in transformed images span has the same image parameters as the standard warped image,
		 * then output data will be just copied to those images without any memory allocation.
		 * New images will be allocated otherwise.
		 * @return Result with error code.
		 * @see Span, Image, Detection, Result and FSDKError for details.
		 * @note images format must be R8G8B8, @see Format.
		 * @note all spans should be based on user owned continuous collections.
		 * @note all spans should be equal size.
		 * */
		virtual Result<FSDKError>
		warp(
			Span<const Image> images,
			Span<const Detection> detections,
			Span<Image> transformedImages) const noexcept = 0;

	};
	
}