/*
 * Copyright (C) 2025 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.eyedropper.util

import android.content.Context
import android.graphics.PixelFormat
import android.hardware.display.DisplayManager
import android.view.Gravity
import android.view.View
import android.view.WindowManager
import javax.inject.Inject
import javax.inject.Singleton

@Singleton
class WindowHelper @Inject constructor(
    private val displayManager: DisplayManager
) {
    private fun getFocusedTransparentOverlayLayoutParams(): WindowManager.LayoutParams {
        val layoutFlags =
            WindowManager.LayoutParams.FLAG_LAYOUT_IN_SCREEN or // Ignore parent constraints
                    WindowManager.LayoutParams.FLAG_HARDWARE_ACCELERATED or
                    WindowManager.LayoutParams.FLAG_LAYOUT_NO_LIMITS // Extend out of screen

        val layoutParams = WindowManager.LayoutParams(
            WindowManager.LayoutParams.MATCH_PARENT, // Span entire width
            WindowManager.LayoutParams.MATCH_PARENT, // Span entire height
            WindowManager.LayoutParams.TYPE_SCREENSHOT, // Highest Z-order to emulate pointer
            layoutFlags,
            PixelFormat.TRANSLUCENT // Make window background transparent
        ).apply {
            title = "EyeDropperOverlay"
            gravity = Gravity.TOP or Gravity.START // Set origin to be top left
        }
        return layoutParams
    }

    fun addFocusedTransparentOverlay(windowManager: WindowManager, view: View) {
        val layoutParams = getFocusedTransparentOverlayLayoutParams()
        windowManager.addView(view, layoutParams)
    }

    fun removeView(windowManager: WindowManager, view: View) {
        windowManager.removeView(view)
    }

    fun getWindowContext(context: Context, displayId: Int): Context {
        val defaultDisplay = displayManager.getDisplay(displayId)
            ?: throw IllegalArgumentException("Display $displayId not found")
        val displayContext = context.createDisplayContext(defaultDisplay)

        return displayContext.createWindowContext(WindowManager.LayoutParams.TYPE_SCREENSHOT, null)
    }

    fun getWindowManager(displayContext: Context): WindowManager {
        return displayContext.getSystemService(WindowManager::class.java)
    }
}