packages/SystemUI/src/com/android/systemui/statusbar/MediaArtworkProcessor.kt

/*
 * Copyright (C) 2019 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License
 */

package com.android.systemui.statusbar

import android.annotation.ColorInt
import android.content.Context
import android.graphics.Bitmap
import android.graphics.Canvas
import android.graphics.Point
import android.graphics.Rect
import android.renderscript.Allocation
import android.renderscript.Element
import android.renderscript.RenderScript
import android.renderscript.ScriptIntrinsicBlur
import android.util.MathUtils
import com.android.internal.graphics.ColorUtils

import javax.inject.Inject
import javax.inject.Singleton

private const val COLOR_ALPHA = (255 * 0.7f).toInt()
private const val BLUR_RADIUS = 25f
private const val DOWNSAMPLE = 6

@Singleton
class MediaArtworkProcessor @Inject constructor() {

    private val mTmpSize = Point()
    private var mArtworkCache: Bitmap? = null

    fun processArtwork(context: Context, artwork: Bitmap, @ColorInt color: Int): Bitmap {
        if (mArtworkCache != null) {
            return mArtworkCache!!
        }

        context.display.getSize(mTmpSize)
        val renderScript = RenderScript.create(context)
        val rect = Rect(0, 0, artwork.width, artwork.height)
        MathUtils.fitRect(rect, Math.max(mTmpSize.x / DOWNSAMPLE, mTmpSize.y / DOWNSAMPLE))
        val inBitmap = Bitmap.createScaledBitmap(artwork, rect.width(), rect.height(),
                true /* filter */)
        val input = Allocation.createFromBitmap(renderScript, inBitmap,
                Allocation.MipmapControl.MIPMAP_NONE, Allocation.USAGE_GRAPHICS_TEXTURE)
        val outBitmap = Bitmap.createBitmap(inBitmap.width, inBitmap.height,
                Bitmap.Config.ARGB_8888)
        val output = Allocation.createFromBitmap(renderScript, outBitmap)
        val blur = ScriptIntrinsicBlur.create(renderScript, Element.U8_4(renderScript))
        blur.setRadius(BLUR_RADIUS)
        blur.setInput(input)
        blur.forEach(output)
        output.copyTo(outBitmap)

        input.destroy()
        output.destroy()
        inBitmap.recycle()
        blur.destroy()

        val canvas = Canvas(outBitmap)
        canvas.drawColor(ColorUtils.setAlphaComponent(color, COLOR_ALPHA))
        return outBitmap
    }

    fun clearCache() {
        mArtworkCache?.recycle()
        mArtworkCache = null
    }
}