package com.contentsquare.rn.csq

import android.app.Activity
import android.graphics.Bitmap
import android.os.Build
import android.util.Log
import android.webkit.WebView
import android.webkit.WebViewClient
import com.contentsquare.CSQ
import com.contentsquare.android.R
import com.contentsquare.rn.utils.ReactNativeUiThreadUtil
import com.contentsquare.rn.utils.ReactNativeViewFinder
import com.contentsquare.rn.utils.VersionUtils.isApiLevelAtLeast
import com.contentsquare.rn.utils.WebViewUtils.getWebViewClient
import com.contentsquare.rn.webview.BridgeWebViewClient
import com.facebook.react.bridge.ReactApplicationContext
import com.facebook.react.modules.core.DeviceEventManagerModule

class CSQWebView(
    private val reactContext: ReactApplicationContext,
    private val reactNativeUiThreadUtil: ReactNativeUiThreadUtil,
    private val reactNativeViewFinder: ReactNativeViewFinder,

) {

    fun registerWebView (webViewTag: Int) {
        val activity: Activity = reactContext.getCurrentActivity() ?: return
        reactNativeUiThreadUtil.runOnUiThread {
            reactNativeViewFinder.findWebView(
                reactContext,
                webViewTag
            ) { webView: WebView? ->
                Log.i("CSLIB", "WebView found in native bridge. Ready to be injected")

                CSQ.registerWebView(prepareWebView(activity, webView!!))

                // getting React Native's webview client before setting a new webview client
                val rnWebViewClient = getWebViewClient(webView)


                // replacing Native SDK webview client with custom one
                handleBlankPageRemoval(webView, rnWebViewClient)
                reactContext
                    .getJSModule<DeviceEventManagerModule.RCTDeviceEventEmitter>(
                        DeviceEventManagerModule.RCTDeviceEventEmitter::class.java
                    )
                    .emit("onCSQWebViewInjected", null)
            }
        }
    }

    fun unregisterWebView (webViewTag: Int) {
        val activity = reactContext.currentActivity ?: return

        reactNativeUiThreadUtil.runOnUiThread {
            reactNativeViewFinder.findWebView(
                reactContext,
                webViewTag
            ) { webView: WebView? ->
                Log.i("CSLIB", "WebView found in native bridge. Ready to remove injection")
                CSQ.unregisterWebView(prepareWebView(activity, webView!!))
            }
        }
    }

    private fun prepareWebView(activity: Activity, webView: WebView): WebView {
        webView.setTag(R.string.contentsquare_react_native_web_view_activity_tag, activity)
        return webView
    }

    /*
    * removes "about:blank" from history. This page is added due to the current implementation in RN
    *
    * this method only works for API levels 26 and up
    * */
    private fun handleBlankPageRemoval(webView: WebView, rnWebViewClient: WebViewClient?) {
        if (isApiLevelAtLeast(Build.VERSION_CODES.O)) {
            if (rnWebViewClient != null) {
                webView.webViewClient = object : BridgeWebViewClient(rnWebViewClient) {
                    override fun onPageStarted(view: WebView?, url: String?, favicon: Bitmap?) {
                        super.onPageStarted(view, url, favicon)
                        val backForwardList = webView.copyBackForwardList()

                        // We need to remove the blank page introduced when loading the first time with "undefined" url from JS
                        if (backForwardList.size == 2 && "about:blank" == backForwardList.getItemAtIndex(
                                0
                            ).originalUrl
                        ) {
                            webView.clearHistory()
                        }
                    }
                }
            } else {
                Log.i("CSLIB", "Handling blank page removal not performed: web client not found")
            }
        } else {
            Log.i("CSLIB", "Handling blank page removal not performed: API leve lower than 26")
        }
    }
}