/*
 * This file is part of the Scandit Data Capture SDK
 *
 * Copyright (C) 2019- Scandit AG. All rights reserved.
 */

package com.scandit.datacapture.cordova.core.handlers

import android.app.Activity
import android.content.Context
import android.graphics.Color
import android.view.View
import android.view.ViewGroup
import android.view.ViewGroup.LayoutParams.MATCH_PARENT
import com.scandit.datacapture.cordova.core.data.ResizeAndMoveInfo
import com.scandit.datacapture.cordova.core.utils.bringContainerToFront
import com.scandit.datacapture.cordova.core.utils.pxFromDp
import com.scandit.datacapture.cordova.core.utils.removeFromParent
import com.scandit.datacapture.core.ui.DataCaptureView
import java.lang.ref.WeakReference

class DataCaptureViewHandler {
    private var latestInfo: ResizeAndMoveInfo = ResizeAndMoveInfo(0f, 0f, 0f, 0f, false)
    private var isVisible: Boolean = false
    private var dataCaptureViewReference: WeakReference<DataCaptureView>? = null
    private var webViewReference: WeakReference<View>? = null
    private var backgroundViewReference: WeakReference<View>? = null

    val dataCaptureView: DataCaptureView?
        get() = dataCaptureViewReference?.get()

    private val webView: View?
        get() = webViewReference?.get()

    private val backgroundView: View?
        get() = backgroundViewReference?.get()

    fun attachDataCaptureView(dataCaptureView: DataCaptureView, activity: Activity) {
        addDataCaptureView(dataCaptureView, activity)
    }

    fun attachWebView(webView: View) {
        if (this.webView != webView) {
            webViewReference = WeakReference(webView)
        }
    }

    fun setVisible() {
        isVisible = true
        render()
    }

    fun setInvisible() {
        isVisible = false
        render()
    }

    fun setResizeAndMoveInfo(info: ResizeAndMoveInfo) {
        latestInfo = info
        render()
    }

    fun disposeCurrentWebView() {
        webViewReference = null
        val dcView = dataCaptureView ?: return
        removeDataCaptureView(dcView)
    }

    private fun disposeCurrentBackgroundView() {
        val backgroundView = backgroundView ?: return
        backgroundViewReference = null
        removeView(backgroundView)
    }

    private fun createBackgroundView(context: Context): View = View(context).apply {
        setBackgroundColor(Color.WHITE)
    }

    private fun addDataCaptureView(dataCaptureView: DataCaptureView, activity: Activity) {
        dataCaptureViewReference = WeakReference(dataCaptureView)
        activity.runOnUiThread {
            val backgroundView = createBackgroundView(activity)
            backgroundViewReference = WeakReference(backgroundView)
            activity.addContentView(
                backgroundView,
                ViewGroup.LayoutParams(MATCH_PARENT, MATCH_PARENT)
            )
            // Bring the WebView's content-frame container to the front so backgroundView
            // (added via addContentView) doesn't end up covering the whole WebView on
            // cordova-android 15+, where the WebView is wrapped in an intermediate
            // rootLayout.
            webView?.bringContainerToFront()
            webView?.setBackgroundColor(Color.TRANSPARENT)

            dataCaptureView.parent?.let {
                (it as ViewGroup).removeView(dataCaptureView)
            }
            // Add the DataCaptureView into the WebView's own parent so the two views
            // share a single coordinate frame. latestInfo positions come from the JS
            // getBoundingClientRect() and are therefore WebView-relative; placing the
            // overlay as a sibling of the WebView means those coordinates map directly
            // (offset only by the WebView's own position within that shared parent)
            // with no screen-space translation, and the overlay is clipped to the same
            // bounds as the WebView. Falls back to the activity content frame if the
            // WebView isn't attached yet.
            val layoutParams = ViewGroup.LayoutParams(
                latestInfo.width.pxFromDp(activity).toInt(),
                latestInfo.height.pxFromDp(activity).toInt()
            )
            val container = webView?.parent as? ViewGroup
            if (container != null) {
                container.addView(dataCaptureView, layoutParams)
            } else {
                activity.addContentView(dataCaptureView, layoutParams)
            }
            render()
        }
    }

    fun removeDataCaptureView(dataCaptureView: DataCaptureView) {
        if (dataCaptureView == dataCaptureViewReference?.get()) {
            dataCaptureViewReference = null
            disposeCurrentBackgroundView()
        }
        removeView(dataCaptureView)
    }

    private fun removeView(view: View) {
        view.post {
            view.removeFromParent()
        }
    }

    // Update the view visibility, position and size.
    private fun render() {
        val view = dataCaptureView ?: return
        renderNoAnimate(view)
    }

    private fun renderNoAnimate(dataCaptureView: DataCaptureView) {
        dataCaptureView.post {
            dataCaptureView.visibility = if (isVisible) View.VISIBLE else View.GONE
            // DataCaptureView shares the WebView's parent, so latestInfo (WebView-relative,
            // from getBoundingClientRect()) maps directly, offset only by the WebView's own
            // position within that shared parent. No screen-space translation needed, and
            // this stays correct regardless of any edge-to-edge inset applied to the WebView.
            val webView = webView
            val context = dataCaptureView.context
            dataCaptureView.x = latestInfo.left.pxFromDp(context) + (webView?.x ?: 0f)
            dataCaptureView.y = latestInfo.top.pxFromDp(context) + (webView?.y ?: 0f)
            dataCaptureView.layoutParams.apply {
                width = latestInfo.width.pxFromDp(context).toInt()
                height = latestInfo.height.pxFromDp(context).toInt()
            }
            if (latestInfo.shouldBeUnderWebView) {
                webView?.bringToFront()
            } else {
                dataCaptureView.bringToFront()
            }
            dataCaptureView.requestLayout()
        }
    }
}