implement basic methods for descrambling images

app/build.gradle

@@ -82,7 +82,11 @@ afterEvaluate {
 }
 dependencies {
 	//noinspection GradleDependency
-	implementation('com.github.KotatsuApp:kotatsu-parsers:078b59b1e2') {
+	// TODO: change bac
+//	implementation('com.github.KotatsuApp:kotatsu-parsers:078b59b1e2') {
+//		exclude group: 'org.json', module: 'json'
+//	}
+	implementation('com.github.AwkwardPeak7:kotatsu-parsers:d7d42465de') {
 		exclude group: 'org.json', module: 'json'
 	}
 

app/src/main/kotlin/org/koitharu/kotatsu/core/parser/BitmapImpl.kt

@@ -0,0 +1,48 @@
+package org.koitharu.kotatsu.core.parser
+
+import android.graphics.Canvas
+import android.graphics.Bitmap as AndroidBitmap
+import android.graphics.Rect as AndroidRect
+import org.koitharu.kotatsu.parsers.bitmap.Bitmap
+import org.koitharu.kotatsu.parsers.bitmap.Rect
+
+class BitmapImpl private constructor() : Bitmap {
+
+	lateinit var androidBitmap: AndroidBitmap
+
+	private lateinit var canvas: Canvas
+
+	override val height: Int
+		get() = androidBitmap.height
+
+	override val width: Int
+		get() = androidBitmap.width
+
+	override fun drawBitmap(sourceBitmap: Bitmap, src: Rect, dst: Rect) {
+		val androidSourceBitmap = (sourceBitmap as BitmapImpl).androidBitmap
+
+		canvas.drawBitmap(androidSourceBitmap, src.toAndroidRect(), dst.toAndroidRect(), null)
+	}
+
+	companion object {
+		fun create(width: Int, height: Int): Bitmap {
+			val instance = BitmapImpl()
+			instance.androidBitmap = AndroidBitmap.createBitmap(width, height, AndroidBitmap.Config.ARGB_8888)
+			instance.canvas = Canvas(instance.androidBitmap)
+
+			return instance
+		}
+
+		fun create(bitmap: AndroidBitmap): Bitmap {
+			val instance = BitmapImpl()
+			instance.androidBitmap = bitmap.copy(AndroidBitmap.Config.ARGB_8888, true)
+			instance.canvas = Canvas(instance.androidBitmap)
+
+			return instance
+		}
+	}
+}
+
+private fun Rect.toAndroidRect(): AndroidRect {
+	return AndroidRect(left, top, right, bottom)
+}

app/src/main/kotlin/org/koitharu/kotatsu/core/parser/MangaLoaderContextImpl.kt

@@ -1,7 +1,9 @@
 package org.koitharu.kotatsu.core.parser
 
+import android.graphics.Bitmap as AndroidBitmap
 import android.annotation.SuppressLint
 import android.content.Context
+import android.graphics.BitmapFactory
 import android.util.Base64
 import android.webkit.WebView
 import androidx.annotation.MainThread
@@ -10,7 +12,11 @@ import dagger.hilt.android.qualifiers.ApplicationContext
 import kotlinx.coroutines.Dispatchers
 import kotlinx.coroutines.runBlocking
 import kotlinx.coroutines.withContext
+import okhttp3.MediaType.Companion.toMediaType
 import okhttp3.OkHttpClient
+import okhttp3.Response
+import okhttp3.ResponseBody.Companion.asResponseBody
+import okio.Buffer
 import org.koitharu.kotatsu.core.network.MangaHttpClient
 import org.koitharu.kotatsu.core.network.cookies.MutableCookieJar
 import org.koitharu.kotatsu.core.prefs.SourceSettings
@@ -19,6 +25,7 @@ import org.koitharu.kotatsu.core.util.ext.printStackTraceDebug
 import org.koitharu.kotatsu.core.util.ext.sanitizeHeaderValue
 import org.koitharu.kotatsu.core.util.ext.toList
 import org.koitharu.kotatsu.parsers.MangaLoaderContext
+import org.koitharu.kotatsu.parsers.bitmap.Bitmap
 import org.koitharu.kotatsu.parsers.config.MangaSourceConfig
 import org.koitharu.kotatsu.parsers.model.MangaSource
 import org.koitharu.kotatsu.parsers.network.UserAgents
@@ -68,6 +75,28 @@ class MangaLoaderContextImpl @Inject constructor(
 		return LocaleListCompat.getAdjustedDefault().toList()
 	}
 
+	override fun redrawImageResponse(response: Response, redraw: (image: Bitmap) -> Bitmap): Response {
+		val image = requireNotNull(response.body) {
+			"Response is null"
+		}.byteStream()
+
+		val bitmap = BitmapFactory.decodeStream(image)
+		val result = redraw(BitmapImpl.create(bitmap)) as BitmapImpl
+
+		val body = Buffer().run {
+			result.androidBitmap.compress(AndroidBitmap.CompressFormat.JPEG, 90, outputStream())
+			asResponseBody("image/jpeg".toMediaType())
+		}
+
+		return response.newBuilder()
+			.body(body)
+			.build()
+	}
+
+	override fun createBitmap(width: Int, height: Int): Bitmap {
+		return BitmapImpl.create(width, height)
+	}
+
 	@MainThread
 	private fun obtainWebView(): WebView {
 		return webViewCached?.get() ?: WebView(androidContext).also {