package io.legado.app.utils

import android.graphics.Color

import androidx.annotation.ColorInt
import androidx.annotation.FloatRange

object ColorUtil {

    fun intToString(intColor: Int): String {
        return String.format("#%06X", 0xFFFFFF and intColor)
    }


    fun stripAlpha(@ColorInt color: Int): Int {
        return -0x1000000 or color
    }

    @ColorInt
    fun shiftColor(@ColorInt color: Int, @FloatRange(from = 0.0, to = 2.0) by: Float): Int {
        if (by == 1f) return color
        val alpha = Color.alpha(color)
        val hsv = FloatArray(3)
        Color.colorToHSV(color, hsv)
        hsv[2] *= by // value component
        return (alpha shl 24) + (0x00ffffff and Color.HSVToColor(hsv))
    }

    @ColorInt
    fun darkenColor(@ColorInt color: Int): Int {
        return shiftColor(color, 0.9f)
    }

    @ColorInt
    fun lightenColor(@ColorInt color: Int): Int {
        return shiftColor(color, 1.1f)
    }

    fun isColorLight(@ColorInt color: Int): Boolean {
        val darkness = 1 - (0.299 * Color.red(color) + 0.587 * Color.green(color) + 0.114 * Color.blue(color)) / 255
        return darkness < 0.4
    }

    @ColorInt
    fun invertColor(@ColorInt color: Int): Int {
        val r = 255 - Color.red(color)
        val g = 255 - Color.green(color)
        val b = 255 - Color.blue(color)
        return Color.argb(Color.alpha(color), r, g, b)
    }

    @ColorInt
    fun adjustAlpha(@ColorInt color: Int, @FloatRange(from = 0.0, to = 1.0) factor: Float): Int {
        val alpha = Math.round(Color.alpha(color) * factor)
        val red = Color.red(color)
        val green = Color.green(color)
        val blue = Color.blue(color)
        return Color.argb(alpha, red, green, blue)
    }

    @ColorInt
    fun withAlpha(@ColorInt baseColor: Int, @FloatRange(from = 0.0, to = 1.0) alpha: Float): Int {
        val a = Math.min(255, Math.max(0, (alpha * 255).toInt())) shl 24
        val rgb = 0x00ffffff and baseColor
        return a + rgb
    }

    /**
     * Taken from CollapsingToolbarLayout's CollapsingTextHelper class.
     */
    fun blendColors(color1: Int, color2: Int, @FloatRange(from = 0.0, to = 1.0) ratio: Float): Int {
        val inverseRatio = 1f - ratio
        val a = Color.alpha(color1) * inverseRatio + Color.alpha(color2) * ratio
        val r = Color.red(color1) * inverseRatio + Color.red(color2) * ratio
        val g = Color.green(color1) * inverseRatio + Color.green(color2) * ratio
        val b = Color.blue(color1) * inverseRatio + Color.blue(color2) * ratio
        return Color.argb(a.toInt(), r.toInt(), g.toInt(), b.toInt())
    }

}
