Add asset preloader (#1311)

11 files changed, 80 insertions, 56 deletions

diff --git a/app/src/main/kotlin/com/pitchedapps/frost/StartActivity.kt b/app/src/main/kotlin/com/pitchedapps/frost/StartActivity.kt
index 3fafa2a6..37383182 100644
--- a/app/src/main/kotlin/com/pitchedapps/frost/StartActivity.kt
+++ b/app/src/main/kotlin/com/pitchedapps/frost/StartActivity.kt
@@ -37,6 +37,7 @@ import com.pitchedapps.frost.utils.EXTRA_COOKIES
 import com.pitchedapps.frost.utils.L
 import com.pitchedapps.frost.utils.Prefs
 import com.pitchedapps.frost.utils.launchNewTask
+import com.pitchedapps.frost.utils.loadAssets
 import kotlinx.coroutines.Dispatchers
 import kotlinx.coroutines.launch
 import kotlinx.coroutines.withContext
@@ -63,6 +64,7 @@ class StartActivity : KauBaseActivity() {
                 })
                 L.i { "Cookies loaded at time ${System.currentTimeMillis()}" }
                 L._d { "Cookies: ${cookies.joinToString("\t")}" }
+                loadAssets()
                 if (cookies.isNotEmpty()) {
                     if (Prefs.userId != -1L)
                         startActivity<MainActivity>(intentBuilder = {
diff --git a/app/src/main/kotlin/com/pitchedapps/frost/activities/IntroActivity.kt b/app/src/main/kotlin/com/pitchedapps/frost/activities/IntroActivity.kt
index 4aa0966c..04f67276 100644
--- a/app/src/main/kotlin/com/pitchedapps/frost/activities/IntroActivity.kt
+++ b/app/src/main/kotlin/com/pitchedapps/frost/activities/IntroActivity.kt
@@ -53,6 +53,9 @@ import com.pitchedapps.frost.intro.IntroTabTouchFragment
 import com.pitchedapps.frost.utils.Prefs
 import com.pitchedapps.frost.utils.cookies
 import com.pitchedapps.frost.utils.launchNewTask
+import com.pitchedapps.frost.utils.loadAssets
+import kotlinx.coroutines.NonCancellable
+import kotlinx.coroutines.launch
 
 /**
  * Created by Allan Wang on 2017-07-25.
@@ -166,8 +169,11 @@ class IntroActivity : KauBaseActivity(), ViewPager.PageTransformer, ViewPager.On
     }
 
     override fun finish() {
-        launchNewTask<MainActivity>(cookies(), false)
-        super.finish()
+        launch(NonCancellable) {
+            loadAssets()
+            launchNewTask<MainActivity>(cookies(), false)
+            super.finish()
+        }
     }
 
     override fun onBackPressed() {
diff --git a/app/src/main/kotlin/com/pitchedapps/frost/activities/SettingsActivity.kt b/app/src/main/kotlin/com/pitchedapps/frost/activities/SettingsActivity.kt
index 37047448..c3089c7a 100644
--- a/app/src/main/kotlin/com/pitchedapps/frost/activities/SettingsActivity.kt
+++ b/app/src/main/kotlin/com/pitchedapps/frost/activities/SettingsActivity.kt
@@ -53,8 +53,11 @@ import com.pitchedapps.frost.utils.cookies
 import com.pitchedapps.frost.utils.frostChangelog
 import com.pitchedapps.frost.utils.frostNavigationBar
 import com.pitchedapps.frost.utils.launchNewTask
+import com.pitchedapps.frost.utils.loadAssets
 import com.pitchedapps.frost.utils.materialDialogThemed
 import com.pitchedapps.frost.utils.setFrostTheme
+import kotlinx.coroutines.NonCancellable
+import kotlinx.coroutines.launch
 
 /**
  * Created by Allan Wang on 2017-06-06.
@@ -206,7 +209,10 @@ class SettingsActivity : KPrefActivity() {
     override fun onBackPressed() {
         if (!super.backPress()) {
             setResult(resultFlag)
-            finishSlideOut()
+            launch(NonCancellable) {
+                loadAssets()
+                finishSlideOut()
+            }
         }
     }
 
diff --git a/app/src/main/kotlin/com/pitchedapps/frost/injectors/CssAssets.kt b/app/src/main/kotlin/com/pitchedapps/frost/injectors/CssAssets.kt
index de19f99c..77cb4de1 100644
--- a/app/src/main/kotlin/com/pitchedapps/frost/injectors/CssAssets.kt
+++ b/app/src/main/kotlin/com/pitchedapps/frost/injectors/CssAssets.kt
@@ -16,6 +16,7 @@
  */
 package com.pitchedapps.frost.injectors
 
+import android.content.Context
 import android.graphics.Color
 import android.webkit.WebView
 import ca.allanwang.kau.kotlin.lazyContext
@@ -27,6 +28,8 @@ import ca.allanwang.kau.utils.use
 import ca.allanwang.kau.utils.withAlpha
 import com.pitchedapps.frost.utils.L
 import com.pitchedapps.frost.utils.Prefs
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.withContext
 import java.io.BufferedReader
 import java.io.FileNotFoundException
 import java.util.Locale
@@ -36,12 +39,16 @@ import java.util.Locale
  * Mapping of the available assets
  * The enum name must match the css file name
  */
-enum class CssAssets(val folder: String = "themes") : InjectorContract {
+enum class CssAssets(val folder: String = THEME_FOLDER) : InjectorContract {
     MATERIAL_LIGHT, MATERIAL_DARK, MATERIAL_AMOLED, MATERIAL_GLASS, CUSTOM, ROUND_ICONS("components")
     ;
 
-    var file = "${name.toLowerCase(Locale.CANADA)}.css"
-    var injector = lazyContext {
+    private val file = "${name.toLowerCase(Locale.CANADA)}.css"
+
+    /**
+     * Note that while this can be loaded from any thread, it is typically done through [load]
+     */
+    private val injector = lazyContext {
         try {
             var content = it.assets.open("css/$folder/$file").bufferedReader().use(BufferedReader::readText)
             if (this == CUSTOM) {
@@ -72,11 +79,25 @@ enum class CssAssets(val folder: String = "themes") : InjectorContract {
         }
     }
 
-    override fun inject(webView: WebView, callback: (() -> Unit)?) {
-        injector(webView.context).inject(webView, callback)
-    }
+    override fun inject(webView: WebView) =
+        injector(webView.context).inject(webView)
 
     fun reset() {
         injector.invalidate()
     }
+
+    companion object {
+        // Ensures that all non themes and the selected theme are loaded
+        suspend fun load(context: Context) {
+            withContext(Dispatchers.IO) {
+                val currentTheme = Prefs.t.injector as? CssAssets
+                val (themes, others) = CssAssets.values().partition { it.folder == THEME_FOLDER }
+                themes.filter { it != currentTheme }.forEach { it.reset() }
+                currentTheme?.injector?.invoke(context)
+                others.forEach { it.injector.invoke(context) }
+            }
+        }
+    }
 }
+
+private const val THEME_FOLDER = "themes"
diff --git a/app/src/main/kotlin/com/pitchedapps/frost/injectors/CssHider.kt b/app/src/main/kotlin/com/pitchedapps/frost/injectors/CssHider.kt
index 7da6295f..4fd46ae4 100644
--- a/app/src/main/kotlin/com/pitchedapps/frost/injectors/CssHider.kt
+++ b/app/src/main/kotlin/com/pitchedapps/frost/injectors/CssHider.kt
@@ -45,7 +45,6 @@ enum class CssHider(vararg val items: String) : InjectorContract {
             .single(name).build()
     }
 
-    override fun inject(webView: WebView, callback: (() -> Unit)?) {
-        injector.inject(webView, callback)
-    }
+    override fun inject(webView: WebView) =
+        injector.inject(webView)
 }
diff --git a/app/src/main/kotlin/com/pitchedapps/frost/injectors/JsActions.kt b/app/src/main/kotlin/com/pitchedapps/frost/injectors/JsActions.kt
index e64d4faa..44fd01da 100644
--- a/app/src/main/kotlin/com/pitchedapps/frost/injectors/JsActions.kt
+++ b/app/src/main/kotlin/com/pitchedapps/frost/injectors/JsActions.kt
@@ -42,8 +42,8 @@ enum class JsActions(body: String) : InjectorContract {
 
     val function = "(function(){$body})();"
 
-    override fun inject(webView: WebView, callback: (() -> Unit)?) =
-        JsInjector(function).inject(webView, callback)
+    override fun inject(webView: WebView) =
+        JsInjector(function).inject(webView)
 }
 
 @Suppress("NOTHING_TO_INLINE")
diff --git a/app/src/main/kotlin/com/pitchedapps/frost/injectors/JsAssets.kt b/app/src/main/kotlin/com/pitchedapps/frost/injectors/JsAssets.kt
index 0dccc751..4b1bde43 100644
--- a/app/src/main/kotlin/com/pitchedapps/frost/injectors/JsAssets.kt
+++ b/app/src/main/kotlin/com/pitchedapps/frost/injectors/JsAssets.kt
@@ -16,9 +16,12 @@
  */
 package com.pitchedapps.frost.injectors
 
+import android.content.Context
 import android.webkit.WebView
 import ca.allanwang.kau.kotlin.lazyContext
 import com.pitchedapps.frost.utils.L
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.withContext
 import java.io.BufferedReader
 import java.io.FileNotFoundException
 import java.util.Locale
@@ -33,8 +36,8 @@ enum class JsAssets : InjectorContract {
     DOCUMENT_WATCHER
     ;
 
-    var file = "${name.toLowerCase(Locale.CANADA)}.js"
-    var injector = lazyContext {
+    private val file = "${name.toLowerCase(Locale.CANADA)}.js"
+    private val injector = lazyContext {
         try {
             val content = it.assets.open("js/$file").bufferedReader().use(BufferedReader::readText)
             JsBuilder().js(content).single(name).build()
@@ -44,7 +47,15 @@ enum class JsAssets : InjectorContract {
         }
     }
 
-    override fun inject(webView: WebView, callback: (() -> Unit)?) {
-        injector(webView.context).inject(webView, callback)
+    override fun inject(webView: WebView) =
+        injector(webView.context).inject(webView)
+
+    companion object {
+        // Ensures that all non themes and the selected theme are loaded
+        suspend fun load(context: Context) {
+            withContext(Dispatchers.IO) {
+                JsAssets.values().forEach { it.injector.invoke(context) }
+            }
+        }
     }
 }
diff --git a/app/src/main/kotlin/com/pitchedapps/frost/injectors/JsInjector.kt b/app/src/main/kotlin/com/pitchedapps/frost/injectors/JsInjector.kt
index 8ae3a2f4..00c7bcfc 100644
--- a/app/src/main/kotlin/com/pitchedapps/frost/injectors/JsInjector.kt
+++ b/app/src/main/kotlin/com/pitchedapps/frost/injectors/JsInjector.kt
@@ -17,12 +17,7 @@
 package com.pitchedapps.frost.injectors
 
 import android.webkit.WebView
-import com.pitchedapps.frost.utils.L
 import com.pitchedapps.frost.web.FrostWebViewClient
-import io.reactivex.Single
-import io.reactivex.android.schedulers.AndroidSchedulers
-import io.reactivex.disposables.Disposable
-import io.reactivex.subjects.SingleSubject
 import org.apache.commons.text.StringEscapeUtils
 import java.util.Locale
 
@@ -81,8 +76,7 @@ class JsBuilder {
  * Contract for all injectors to allow it to interact properly with a webview
  */
 interface InjectorContract {
-    fun inject(webView: WebView) = inject(webView, null)
-    fun inject(webView: WebView, callback: (() -> Unit)?)
+    fun inject(webView: WebView)
     /**
      * Toggle the injector (usually through Prefs
      * If false, will fallback to an empty action
@@ -93,41 +87,18 @@ interface InjectorContract {
 /**
  * Helper method to inject multiple functions simultaneously with a single callback
  */
-fun WebView.jsInject(vararg injectors: InjectorContract, callback: ((Int) -> Unit)? = null): Disposable? {
-    val validInjectors = injectors.filter { it != JsActions.EMPTY }
-    if (validInjectors.isEmpty()) {
-        callback?.invoke(0)
-        return null
+fun WebView.jsInject(vararg injectors: InjectorContract) {
+    injectors.filter { it != JsActions.EMPTY }.forEach {
+        it.inject(this)
     }
-    L.d { "Injecting ${validInjectors.size} items" }
-    if (callback == null) {
-        validInjectors.forEach { it.inject(this) }
-        return null
-    }
-    val observables = Array(validInjectors.size) { SingleSubject.create<Unit>() }
-    val disposable = Single.zip<Unit, Int>(observables.asList()) { it.size }
-        .observeOn(AndroidSchedulers.mainThread())
-        .subscribe { res, _ ->
-            callback(res)
-        }
-    (0 until validInjectors.size).forEach { i ->
-        validInjectors[i].inject(this) {
-            observables[i].onSuccess(Unit)
-        }
-    }
-    return disposable
 }
 
-fun FrostWebViewClient.jsInject(
-    vararg injectors: InjectorContract,
-    callback: ((Int) -> Unit)? = null
-) = web.jsInject(*injectors, callback = callback)
+fun FrostWebViewClient.jsInject(vararg injectors: InjectorContract) = web.jsInject(*injectors)
 
 /**
  * Wrapper class to convert a function into an injector
  */
 class JsInjector(val function: String) : InjectorContract {
-    override fun inject(webView: WebView, callback: (() -> Unit)?) {
-        webView.evaluateJavascript(function) { callback?.invoke() }
-    }
+    override fun inject(webView: WebView) =
+        webView.evaluateJavascript(function, null)
 }
diff --git a/app/src/main/kotlin/com/pitchedapps/frost/settings/Appearance.kt b/app/src/main/kotlin/com/pitchedapps/frost/settings/Appearance.kt
index 538e20f1..1b1ca796 100644
--- a/app/src/main/kotlin/com/pitchedapps/frost/settings/Appearance.kt
+++ b/app/src/main/kotlin/com/pitchedapps/frost/settings/Appearance.kt
@@ -76,7 +76,7 @@ fun SettingsActivity.getAppearancePrefs(): KPrefAdapterBuilder.() -> Unit = {
     }
 
     fun invalidateCustomTheme() {
-        CssAssets.CUSTOM.injector.invalidate()
+        CssAssets.CUSTOM.reset()
     }
 
     colorPicker(R.string.text_color, Prefs::customTextColor, {
diff --git a/app/src/main/kotlin/com/pitchedapps/frost/utils/Prefs.kt b/app/src/main/kotlin/com/pitchedapps/frost/utils/Prefs.kt
index 303142af..add9c6cd 100644
--- a/app/src/main/kotlin/com/pitchedapps/frost/utils/Prefs.kt
+++ b/app/src/main/kotlin/com/pitchedapps/frost/utils/Prefs.kt
@@ -68,7 +68,7 @@ object Prefs : KPref() {
 
     private val loader = lazyResettable { Theme.values[Prefs.theme] }
 
-    private val t: Theme by loader
+    val t: Theme by loader
 
     val textColor: Int
         get() = t.textColor
diff --git a/app/src/main/kotlin/com/pitchedapps/frost/utils/Utils.kt b/app/src/main/kotlin/com/pitchedapps/frost/utils/Utils.kt
index 3f92c41d..4410b26e 100644
--- a/app/src/main/kotlin/com/pitchedapps/frost/utils/Utils.kt
+++ b/app/src/main/kotlin/com/pitchedapps/frost/utils/Utils.kt
@@ -70,8 +70,11 @@ import com.pitchedapps.frost.facebook.FbItem
 import com.pitchedapps.frost.facebook.FbUrlFormatter.Companion.VIDEO_REDIRECT
 import com.pitchedapps.frost.facebook.USER_AGENT_BASIC
 import com.pitchedapps.frost.facebook.formattedFbUrl
+import com.pitchedapps.frost.injectors.CssAssets
+import com.pitchedapps.frost.injectors.JsAssets
 import kotlinx.coroutines.CoroutineScope
 import kotlinx.coroutines.GlobalScope
+import kotlinx.coroutines.coroutineScope
 import kotlinx.coroutines.launch
 import org.apache.commons.text.StringEscapeUtils
 import org.jsoup.Jsoup
@@ -421,3 +424,8 @@ fun String.unescapeHtml(): String =
     StringEscapeUtils.unescapeXml(this)
         .replace("\\u003C", "<")
         .replace("\\\"", "\"")
+
+suspend fun Context.loadAssets(): Unit = coroutineScope {
+    CssAssets.load(this@loadAssets)
+    JsAssets.load(this@loadAssets)
+}