/**
 * TrackerMap
 * Copyright (C) 2021-2022  Iván Ávalos <avalos@disroot.org>, Henoch Ojeda <imhenoch@protonmail.com>
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Affero General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU Affero General Public License for more details.
 *
 * You should have received a copy of the GNU Affero General Public License
 * along with this program. If not, see <http://www.gnu.org/licenses/>.
 */
package mx.trackermap.TrackerMap.controllers

import kotlinx.coroutines.DelicateCoroutinesApi
import kotlinx.coroutines.GlobalScope
import kotlinx.coroutines.flow.MutableStateFlow
import kotlinx.coroutines.launch
import kotlinx.serialization.json.JsonPrimitive
import mx.trackermap.TrackerMap.client.apis.SessionApi
import mx.trackermap.TrackerMap.client.apis.UsersApi
import mx.trackermap.TrackerMap.client.models.SessionBody
import mx.trackermap.TrackerMap.client.models.User

@DelicateCoroutinesApi
class SessionController(
    private val sessionApi: SessionApi,
    private val usersApi: UsersApi
) {
    sealed class LoginState {
        object Nothing: LoginState()
        object Loading: LoginState()
        object UrlMissing: LoginState()
        object EmailMissing : LoginState()
        object PasswordMissing : LoginState()
        object Failure : LoginState()
        object Success : LoginState()
        object SignOut : LoginState()
    }

    val loginStateFlow = MutableStateFlow<LoginState?>(null)
    val userFlow = MutableStateFlow<User?>(null)

    fun getSession() {
        loginStateFlow.value = LoginState.Loading
        GlobalScope.launch {
            try {
                userFlow.value = sessionApi.sessionGet()
                loginStateFlow.value = LoginState.Success
            } catch (e: Exception) {
                loginStateFlow.value = LoginState.Failure
            }
        }
    }

    fun restoreSession() {
        loginStateFlow.value = LoginState.Loading
        GlobalScope.launch {
            try {
                userFlow.value = sessionApi.sessionGet()
                loginStateFlow.value = LoginState.Success
            } catch (e: Exception) {
                loginStateFlow.value = LoginState.Nothing
            }
        }
    }

    fun login(body: SessionBody) {
        val url = body.url.trim()
        val email = body.email.trim()
        val password = body.password.trim()
        val token = body.fcmToken

        if (url.isEmpty()) {
            loginStateFlow.value = LoginState.UrlMissing
            return
        }

        if (email.isEmpty()) {
            loginStateFlow.value = LoginState.EmailMissing
            return
        }

        if (password.isEmpty()) {
            loginStateFlow.value = LoginState.PasswordMissing
            return
        }

        loginStateFlow.value = LoginState.Loading
        GlobalScope.launch {
            try {
                sessionApi.baseUrl = url
                usersApi.baseUrl = sessionApi.baseUrl
                val session = sessionApi.sessionPost(email, password)
                userFlow.value = session
                usersApi.token = sessionApi.token
                token?.let { registerFcmToken(it) }
                loginStateFlow.value = LoginState.Success
            } catch (e: Exception) {
                loginStateFlow.value = LoginState.Failure
            }
        }
    }

    private suspend fun registerFcmToken(token: String) {
        print("Register FCM token: $token\n")
        try {
            userFlow.value?.let { user ->
                val attributes = user.attributes.toMutableMap()
                attributes["notificationTokens"].toString().let { tokens ->
                    if (tokens == "null" || !tokens.contains(token)) {
                        if (tokens == "null") {
                            attributes["notificationTokens"] = JsonPrimitive(token)
                        } else if (!tokens.contains(token)) {
                            attributes["notificationTokens"] = JsonPrimitive("$tokens,$token")
                        }


                    }
                }
                usersApi.usersIdPut(user.copy(
                    attributes = attributes
                ), user.id!!)
            }
        } catch (e: Exception) {
            e.printStackTrace()
        }
    }

    private suspend fun unregisterFcmToken(token: String) {
        print("Unregister FCM token: $token\n")
        try {
            userFlow.value?.let { user ->
                val attributes = user.attributes.toMutableMap()
                attributes["notificationTokens"].toString().let { tokens ->
                    if (tokens.contains("$token,")) {
                        attributes["notificationTokens"] =
                            JsonPrimitive(token.replace("$token,", ""))
                    } else if (tokens.contains(token)) {
                        attributes["notificationTokens"] =
                            JsonPrimitive(token.replace(token, ""))
                    }
                    usersApi.usersIdPut(user.copy(
                        attributes = attributes
                    ), user.id!!)
                }
            }
        } catch (e: Exception) {
            e.printStackTrace()
        }
    }

    fun logout(token: String?) {
        GlobalScope.launch {
            loginStateFlow.value = LoginState.Loading
            token?.let { unregisterFcmToken(it) }
            sessionApi.sessionDelete()
            loginStateFlow.value = LoginState.SignOut
        }
    }
}