Add support to login through custom OAuth.

app/src/main/java/chat/rocket/android/authentication/login/presentation/LoginPresenter.kt

@@ -207,6 +207,31 @@ class LoginPresenter @Inject constructor(
                         }
                     }
 
+                    getCustomOauthServices(services).let {
+                        for (service in it) {
+                            val serviceName = getCustomOauthServiceName(service)
+
+                            val customOauthUrl = OauthHelper.getCustomOauthUrl(
+                                getCustomOauthHost(service),
+                                getCustomOauthAuthorizePath(service),
+                                getCustomOauthClientId(service),
+                                currentServer,
+                                serviceName,
+                                state,
+                                getCustomOauthScope(service)
+                            )
+
+                            view.addCustomOauthServiceButton(
+                                customOauthUrl,
+                                state,
+                                serviceName,
+                                getCustomOauthServiceNameColor(service),
+                                getCustomOauthButtonColor(service)
+                            )
+                            totalSocialAccountsEnabled++
+                        }
+                    }
+
                     if (totalSocialAccountsEnabled > 0) {
                         view.enableOauthView()
                         if (totalSocialAccountsEnabled > 3) {
@@ -299,6 +324,38 @@ class LoginPresenter @Inject constructor(
         }.toString()
     }
 
+    private fun getCustomOauthServices(listMap: List<Map<String, Any>>): List<Map<String, Any>>  {
+        return listMap.filter { map -> map["custom"] == true }
+    }
+
+    private fun getCustomOauthHost(service: Map<String, Any>): String {
+        return service["serverURL"].toString()
+    }
+
+    private fun getCustomOauthAuthorizePath(service: Map<String, Any>): String {
+        return service["authorizePath"].toString()
+    }
+
+    private fun getCustomOauthClientId(service: Map<String, Any>): String {
+        return service["clientId"].toString()
+    }
+
+    private fun getCustomOauthServiceName(service: Map<String, Any>): String {
+        return service["service"].toString()
+    }
+
+    private fun getCustomOauthScope(service: Map<String, Any>): String {
+        return service["scope"].toString()
+    }
+
+    private fun getCustomOauthButtonColor(service: Map<String, Any>): Int {
+        return service["buttonColor"].toString().parseColor()
+    }
+
+    private fun getCustomOauthServiceNameColor(service: Map<String, Any>): Int {
+        return service["buttonLabelColor"].toString().parseColor()
+    }
+
     private suspend fun saveAccount(username: String) {
         val icon = settings.favicon()?.let {
             currentServer.serverLogoUrl(it)

app/src/main/java/chat/rocket/android/authentication/login/presentation/LoginView.kt

 package chat.rocket.android.authentication.login.presentation
 
-import chat.rocket.android.authentication.server.presentation.VersionCheckView
 import chat.rocket.android.core.behaviours.LoadingView
 import chat.rocket.android.core.behaviours.MessageView
 
@@ -75,7 +74,7 @@ interface LoginView : LoadingView, MessageView {
      * Enables and shows the oauth view if there is login via social accounts enabled by the server settings.
      *
      * REMARK: We must show at maximum *three* social accounts views ([enableLoginByFacebook], [enableLoginByGithub], [enableLoginByGoogle],
-     * [enableLoginByLinkedin], [enableLoginByMeteor], [enableLoginByTwitter] or [enableLoginByGitlab]) for the oauth view.
+     * [enableLoginByLinkedin], [enableLoginByMeteor], [enableLoginByTwitter], [enableLoginByGitlab] or [addCustomOauthServiceButton]) for the oauth view.
      * If the possibility of login via social accounts exceeds 3 different ways we should set up the FAB ([setupFabListener]) to show the remaining view(s).
      */
     fun enableOauthView()
@@ -178,6 +177,24 @@ interface LoginView : LoadingView, MessageView {
      */
     fun setupGitlabButtonListener(gitlabUrl: String, state: String)
 
+    /**
+     * Adds a custom OAuth button in the oauth view.
+     *
+     * @customOauthUrl The custom OAuth url to sets up the button (the listener).
+     * @state A random string generated by the app, which you'll verify later (to protect against forgery attacks).
+     * @serviceName The custom OAuth service name.
+     * @serviceNameColor The custom OAuth service name color (just stylizing).
+     * @buttonColor The color of the custom OAuth button (just stylizing).
+     * @see [enableOauthView]
+     */
+    fun addCustomOauthServiceButton(
+        customOauthUrl: String,
+        state: String,
+        serviceName: String,
+        serviceNameColor: Int,
+        buttonColor: Int
+    )
+
     /**
      * Setups the FloatingActionButton to show more social accounts views (expanding the oauth view interface to show the remaining view(s)).
      */

app/src/main/java/chat/rocket/android/authentication/login/ui/LoginFragment.kt

@@ -2,8 +2,9 @@ package chat.rocket.android.authentication.login.ui
 
 import DrawableHelper
 import android.app.Activity
-import android.app.AlertDialog
 import android.content.Intent
+import android.graphics.Color
+import android.graphics.PorterDuff
 import android.os.Build
 import android.os.Bundle
 import android.support.v4.app.Fragment
@@ -12,10 +13,8 @@ import android.view.LayoutInflater
 import android.view.View
 import android.view.ViewGroup
 import android.view.ViewTreeObserver
-import android.widget.ImageButton
-import android.widget.ScrollView
+import android.widget.*
 import androidx.core.view.postDelayed
-import chat.rocket.android.BuildConfig
 import chat.rocket.android.R
 import chat.rocket.android.authentication.domain.model.LoginDeepLinkInfo
 import chat.rocket.android.authentication.login.presentation.LoginPresenter
@@ -343,6 +342,27 @@ class LoginFragment : Fragment(), LoginView {
         }
     }
 
+    override fun addCustomOauthServiceButton(
+        customOauthUrl: String,
+        state: String,
+        serviceName: String,
+        serviceNameColor: Int,
+        buttonColor: Int
+    ) {
+        ui { activity ->
+            val button = getCustomOauthButton(serviceName, serviceNameColor, buttonColor)
+            social_accounts_container.addView(button)
+
+            button.setOnClickListener {
+                startActivityForResult(
+                    activity.oauthWebViewIntent(customOauthUrl, state),
+                    REQUEST_CODE_FOR_OAUTH
+                )
+                activity.overridePendingTransition(R.anim.slide_up, R.anim.hold)
+            }
+        }
+    }
+
     override fun setupFabListener() {
         ui {
             button_fab.setVisible(true)
@@ -437,4 +457,29 @@ class LoginFragment : Fragment(), LoginView {
             button_fab.setVisible(false)
         }
     }
+
+    /**
+     * Gets a stylized custom OAuth button.
+     */
+    private fun getCustomOauthButton(
+        buttonText: String,
+        buttonTextColor: Int,
+        buttonBgColor: Int
+    ): Button {
+        val params: LinearLayout.LayoutParams = LinearLayout.LayoutParams(
+            LinearLayout.LayoutParams.MATCH_PARENT,
+            LinearLayout.LayoutParams.WRAP_CONTENT
+        )
+
+        val margin = resources.getDimensionPixelSize(R.dimen.screen_edge_left_and_right_margins)
+        params.setMargins(margin, margin, margin, 0)
+
+        val button = Button(context)
+        button.layoutParams = params
+        button.text = buttonText
+        button.setTextColor(buttonTextColor)
+        button.background.setColorFilter(buttonBgColor, PorterDuff.Mode.MULTIPLY)
+
+        return button
+    }
 }
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app/src/main/java/chat/rocket/android/helper/OauthHelper.kt

@@ -91,4 +91,34 @@ object OauthHelper {
                 "&response_type=code" +
                 "&scope=email"
     }
+
+    /**
+     * Returns the Custom Oauth URL.
+     *
+     * @param host The custom OAuth host.
+     * @param authorizePath The OAuth authorization path.
+     * @param clientId The custom OAuth client ID.
+     * @param serverUrl The server URL.
+     * @param serviceName The service name.
+     * @param state An unguessable random string used to protect against forgery attacks.
+     * @param scope The custom OAuth scope.
+     * @return The Custom Oauth URL.
+     */
+    fun getCustomOauthUrl(
+        host: String,
+        authorizePath: String,
+        clientId: String,
+        serverUrl: String,
+        serviceName: String,
+        state: String,
+        scope: String
+    ): String {
+        return host +
+                authorizePath +
+                "?client_id=$clientId" +
+                "&redirect_uri=${serverUrl.removeTrailingSlash()}/_oauth/$serviceName" +
+                "&state=$state" +
+                "&scope=$scope" +
+                "&response_type=code"
+    }
 }

app/src/main/java/chat/rocket/android/util/extensions/String.kt

 package chat.rocket.android.util.extensions
 
+import android.graphics.Color
 import android.util.Patterns
+import timber.log.Timber
 
 fun String.removeTrailingSlash(): String {
     return if (isNotEmpty() && this[length - 1] == '/') {
@@ -32,4 +34,14 @@ fun String.termsOfServiceUrl() = "${removeTrailingSlash()}/terms-of-service"
 
 fun String.privacyPolicyUrl() = "${removeTrailingSlash()}/privacy-policy"
 
-fun String.isValidUrl(): Boolean = Patterns.WEB_URL.matcher(this).matches()
\ No newline at end of file
+fun String.isValidUrl(): Boolean = Patterns.WEB_URL.matcher(this).matches()
+
+fun String.parseColor(): Int {
+    return try {
+        Color.parseColor(this)
+    } catch (exception: IllegalArgumentException) {
+        // Log the exception and get the white color.
+        Timber.e(exception)
+        Color.parseColor("white")
+    }
+}
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