package network.rs485.ben.computervision

import org.opencv.core.*
import org.opencv.imgproc.Imgproc

open class IdentifiableEntity(
    entity: Entity,
    private val dimensionProvider: DimensionProvider = CroppingDimensionProvider(entity.lines.toList()),
) {
    companion object {
        const val DIST_TRANSFORM_MASK_SIZE: Int = 3

        // DIST_L2 is the simple euclidean distances
        const val DIST_TRANSFORM_FUNC = Imgproc.DIST_L2
    }

    val rows: Int = dimensionProvider.maxY - dimensionProvider.minY + 1
    val cols: Int = dimensionProvider.maxX - dimensionProvider.minX + 1
    val rect: Rect
        get() = Rect(dimensionProvider.minX, dimensionProvider.minY, cols, rows)
    val lines = entity.lines.toList()
    val transformedLines = lines.map {
        transformPixel(it.first) to transformPixel(it.second)
    }
    val entityMask: Mat = Mat(rows, cols, CvType.CV_8UC1).also { maskMat ->
        maskMat.setTo(COLOR_BLACK)
        transformedColor(COLOR_WHITE, maskMat)
    }
    val distanceMat: Mat = Mat(rows, cols, CvType.CV_32FC1).also { distanceMat ->
        Imgproc.distanceTransform(entityMask, distanceMat, DIST_TRANSFORM_FUNC, DIST_TRANSFORM_MASK_SIZE)
    }
    val minMaxDistance: Core.MinMaxLocResult by lazy { Core.minMaxLoc(distanceMat, entityMask) }

    fun transformedColor(color: Scalar, image: Mat) {
        transformedLines.forEach {
            image.drawLine(it, color)
        }
    }

    fun transformPixel(pixel: Pixel) = Pixel(pixel.x - dimensionProvider.minX, pixel.y - dimensionProvider.minY)

    open fun release() {
        entityMask.release()
        distanceMat.release()
    }

    override fun toString(): String {
        return "IdentifiableEntity($rect)"
    }
}

internal inline fun <T> withIdEntity(entity: Entity, block: (identity: IdentifiableEntity) -> T): T =
    IdentifiableEntity(entity).let { identity ->
        autoclean(identity, identity::release, block)
    }