//
//  RNMMChatView.kt
//  MobileMessagingReactNative
//
//  Copyright (c) 2016-2025 Infobip Limited
//  Licensed under the Apache License, Version 2.0
//

package org.infobip.reactlibrary.mobilemessaging

import android.content.Context
import android.util.AttributeSet
import android.view.ViewGroup
import android.view.ViewParent
import android.widget.FrameLayout
import androidx.fragment.app.FragmentActivity
import org.infobip.mobile.messaging.chat.view.InAppChatFragment
import org.infobip.mobile.messaging.chat.core.InAppChatException
import com.facebook.react.bridge.ReactApplicationContext

/**
 * RNMMChatView is a custom view that integrates the InAppChatFragment from the Infobip Mobile Messaging Chat SDK into a React Native application.
 */
class RNMMChatView @JvmOverloads constructor(
    context: Context,
    attrs: AttributeSet? = null,
    defStyleAttr: Int = 0,
    defStyleRes: Int = 0
) : FrameLayout(context, attrs, defStyleAttr, defStyleRes) {

    private var cachedFragment: InAppChatFragment? = null
    private var useCustomErrorHandler = false

    companion object {
        private const val TAG = "RNMMChatView"
        private const val EVENT_INAPPCHAT_EXCEPTION_RECEIVED = "inAppChat.internal.exceptionReceived"
    }

    private fun getFragment(fragmentActivity: FragmentActivity?): InAppChatFragment? {
        return cachedFragment ?: (fragmentActivity?.supportFragmentManager?.findFragmentByTag(Utils.RN_IN_APP_CHAT_FRAGMENT_TAG) as? InAppChatFragment)
    }

    fun add(reactContext: ReactApplicationContext?, fragmentActivity: FragmentActivity?) {
        runCatchingExceptions("add()") {
            val fragment = getFragment(fragmentActivity) ?: InAppChatFragment()
            cachedFragment = fragment
            fragment.withToolbar = false
            fragment.withInput = true
            if (useCustomErrorHandler && reactContext != null) {
                fragment.errorsHandler = createErrorsHandler(reactContext)
            }

            val parent: ViewParent? = this.parent
            if (parent is ViewGroup) {
                setupLayoutHack(parent)
            } else {
                RNMMLogger.e(TAG, "Parent is not ViewGroup, cannot show InAppChatFragment.")
            }

            val fragmentManager = fragmentActivity?.supportFragmentManager
            if (fragmentManager != null) {
                fragmentManager.beginTransaction()
                    .replace(this.id, fragment, Utils.RN_IN_APP_CHAT_FRAGMENT_TAG)
                    .commitNow()
            } else {
                RNMMLogger.e(TAG, "FragmentManager is null, cannot add InAppChatFragment.")
            }
        }
    }

    fun remove(fragmentActivity: FragmentActivity?) {
        runCatchingExceptions("remove()") {
            useCustomErrorHandler = false
            val fragmentManager = fragmentActivity?.supportFragmentManager
            val fragment = getFragment(fragmentActivity)
            if (fragment != null && fragmentManager != null) {
                fragmentManager.beginTransaction()
                    .remove(fragment)
                    .commitNow()
                cachedFragment = null
            } else {
                RNMMLogger.e(TAG, "InAppChatFragment or FragmentManager is null, cannot remove InAppChatFragment.")
            }
        }
    }

    fun showThreadsList(fragmentActivity: FragmentActivity?) {
        runCatchingExceptions("showThreadsList()") {
            val fragment = getFragment(fragmentActivity)
            if (fragment != null) {
                fragment.showThreadList()
            } else {
                RNMMLogger.e(TAG, "InAppChatFragment is null, cannot show threads list.")
            }
        }
    }

    fun setExceptionHandler(isHandlerPresent: Boolean, reactContext: ReactApplicationContext?, fragmentActivity: FragmentActivity?) {
        runCatchingExceptions("setExceptionHandler()", arrayOf(isHandlerPresent)) {
            useCustomErrorHandler = isHandlerPresent
            val fragment = getFragment(fragmentActivity)
            if (fragment != null && reactContext != null) {
                if (isHandlerPresent) {
                    fragment.errorsHandler = createErrorsHandler(reactContext)
                } else {
                    fragment.errorsHandler = fragment.defaultErrorsHandler
                }
            }
        }
    }

    private fun createErrorsHandler(reactContext: ReactApplicationContext): InAppChatFragment.ErrorsHandler {
        return object : InAppChatFragment.ErrorsHandler {
            override fun handleError(exception: InAppChatException): Boolean {
                ReactNativeEvent.send(EVENT_INAPPCHAT_EXCEPTION_RECEIVED, reactContext, exception.toJSON())
                return true
            }
        }
    }

    //region Helpers
    private fun runCatchingExceptions(functionName: String, args: Array<out Any?> = emptyArray(), errorHandler: ((Throwable) -> Unit)? = null, block: () -> Unit) {
        val argsLog = if (args.isEmpty()) "" else " Arguments: ${args.joinToString()}"
        RNMMLogger.d(TAG, "$functionName$argsLog")
        try {
            block()
        } catch (throwable: Throwable) {
            errorHandler?.invoke(throwable) ?: RNMMLogger.e(TAG, "$functionName error: ${throwable.message}", throwable)
        }
    }

    private fun setupLayoutHack(view: ViewGroup) {
        view.viewTreeObserver.addOnGlobalLayoutListener { view.requestLayout() }
    }

    override fun requestLayout() {
        super.requestLayout()
        // RN issue https://github.com/facebook/react-native/issues/17968
        // Without this layout will not be called and view will not be displayed,
        // because RN doesn't dispatches events to android views properly
        post(measureAndLayout)
    }

    private val measureAndLayout = Runnable {
        measure(
            MeasureSpec.makeMeasureSpec(width, MeasureSpec.EXACTLY),
            MeasureSpec.makeMeasureSpec(height, MeasureSpec.EXACTLY)
        )
        layout(left, top, right, bottom)
    }
    //endregion
}