From 802cdd4c46f2b0e127149ed4f753abb80c096cea Mon Sep 17 00:00:00 2001
From: Nik Clayton <nik@ngo.org.uk>
Date: Tue, 3 Oct 2023 12:56:30 +0200
Subject: [PATCH] feat: Embed the privacy policy in the app (#139)

Instead of linking to the privacy policy embed it in the app as a string
of HTML.

The string is created with a new `markdown2resource` plugin, which
converts `PRIVACY.md` to HTML and generates a Java class with the HTML
content.

Create `PrivacyPolicyActivity` to display the HTML in a `WebView`, and
link to it from `AboutActivity`.
---
 app/build.gradle                              |   6 +
 app/lint-baseline.xml                         |  13 +-
 app/src/main/AndroidManifest.xml              |   1 +
 app/src/main/java/app/pachli/AboutActivity.kt |   6 +-
 .../java/app/pachli/PrivacyPolicyActivity.kt  |  32 ++++
 .../java/app/pachli/di/ActivitiesModule.kt    |   4 +
 app/src/main/res/layout/activity_about.xml    |   5 +-
 .../res/layout/activity_privacy_policy.xml    |  21 +++
 app/src/main/res/values/strings.xml           |   2 +-
 plugins/markdown2resource/README.md           |  56 +++++++
 plugins/markdown2resource/build.gradle.kts    |  50 ++++++
 .../Markdown2ResourcePlugin.kt                | 156 ++++++++++++++++++
 settings.gradle                               |   2 +
 13 files changed, 337 insertions(+), 17 deletions(-)
 create mode 100644 app/src/main/java/app/pachli/PrivacyPolicyActivity.kt
 create mode 100644 app/src/main/res/layout/activity_privacy_policy.xml
 create mode 100644 plugins/markdown2resource/README.md
 create mode 100644 plugins/markdown2resource/build.gradle.kts
 create mode 100644 plugins/markdown2resource/src/main/kotlin/app/pachli/plugins/markdown2resource/Markdown2ResourcePlugin.kt

diff --git a/app/build.gradle b/app/build.gradle
index 5ea7f0fd1..9ea14c4f5 100644
--- a/app/build.gradle
+++ b/app/build.gradle
@@ -5,6 +5,8 @@ plugins {
     alias(libs.plugins.kotlin.kapt)
     alias(libs.plugins.kotlin.parcelize)
     alias(libs.plugins.aboutlibraries)
+
+    id "app.pachli.plugins.markdown2resource"
 }
 
 apply from: 'gitTools.gradle'
@@ -139,6 +141,10 @@ aboutLibraries {
     prettyPrint = true
 }
 
+markdown2resource {
+    files = [ layout.projectDirectory.file('../PRIVACY.md') ]
+}
+
 // library versions are in PROJECT_ROOT/gradle/libs.versions.toml
 dependencies {
     implementation libs.kotlinx.coroutines.android
diff --git a/app/lint-baseline.xml b/app/lint-baseline.xml
index f46fb7cd5..9f8bb0d86 100644
--- a/app/lint-baseline.xml
+++ b/app/lint-baseline.xml
@@ -47,7 +47,7 @@
         errorLine2="        ~~~~~~~~~~~~">
         <location
             file="build.gradle"
-            line="33"
+            line="35"
             column="9"/>
     </issue>
 
@@ -2064,17 +2064,6 @@
             column="9"/>
     </issue>
 
-    <issue
-        id="SyntheticAccessor"
-        message="Access to `private` method `setClickableTextWithoutUnderlines` of class `AboutActivityKt` requires synthetic accessor"
-        errorLine1="        binding.aboutPrivacyPolicyTextView.setClickableTextWithoutUnderlines(R.string.about_privacy_policy)"
-        errorLine2="        ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~">
-        <location
-            file="src/main/java/app/pachli/AboutActivity.kt"
-            line="76"
-            column="9"/>
-    </issue>
-
     <issue
         id="SyntheticAccessor"
         message="Access to `private` method `isSameDate` of class `Companion` requires synthetic accessor"
diff --git a/app/src/main/AndroidManifest.xml b/app/src/main/AndroidManifest.xml
index 2a3aaf71d..69a076827 100644
--- a/app/src/main/AndroidManifest.xml
+++ b/app/src/main/AndroidManifest.xml
@@ -145,6 +145,7 @@
         </activity>
         <activity android:name=".ListsActivity" />
         <activity android:name=".LicenseActivity" />
+        <activity android:name=".PrivacyPolicyActivity" />
         <activity android:name=".components.filters.FiltersActivity" />
         <activity android:name=".components.trending.TrendingActivity" />
         <activity android:name=".components.followedtags.FollowedTagsActivity" />
diff --git a/app/src/main/java/app/pachli/AboutActivity.kt b/app/src/main/java/app/pachli/AboutActivity.kt
index 9a0c1c397..b5e69a285 100644
--- a/app/src/main/java/app/pachli/AboutActivity.kt
+++ b/app/src/main/java/app/pachli/AboutActivity.kt
@@ -73,7 +73,11 @@ class AboutActivity : BottomSheetActivity(), Injectable {
         binding.aboutLicenseInfoTextView.setClickableTextWithoutUnderlines(R.string.about_pachli_license)
         binding.aboutWebsiteInfoTextView.setClickableTextWithoutUnderlines(R.string.about_project_site)
         binding.aboutBugsFeaturesInfoTextView.setClickableTextWithoutUnderlines(R.string.about_bug_feature_request_site)
-        binding.aboutPrivacyPolicyTextView.setClickableTextWithoutUnderlines(R.string.about_privacy_policy)
+
+        binding.aboutPrivacyPolicyTextView.setOnClickListener {
+            val intent = Intent(this, PrivacyPolicyActivity::class.java)
+            startActivity(intent)
+        }
 
         binding.appProfileButton.setOnClickListener {
             viewUrl(BuildConfig.SUPPORT_ACCOUNT_URL)
diff --git a/app/src/main/java/app/pachli/PrivacyPolicyActivity.kt b/app/src/main/java/app/pachli/PrivacyPolicyActivity.kt
new file mode 100644
index 000000000..53ea5fe88
--- /dev/null
+++ b/app/src/main/java/app/pachli/PrivacyPolicyActivity.kt
@@ -0,0 +1,32 @@
+/*
+ * Copyright 2023 Pachli Association
+ *
+ * This file is a part of Pachli.
+ *
+ * This program is free software; you can redistribute it and/or modify it under the terms of the
+ * GNU General Public License as published by the Free Software Foundation; either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * Pachli 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 General
+ * Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along with Pachli; if not,
+ * see <http://www.gnu.org/licenses>.
+ */
+
+package app.pachli
+
+import android.os.Bundle
+import android.util.Base64
+import app.pachli.databinding.ActivityPrivacyPolicyBinding
+
+class PrivacyPolicyActivity : BaseActivity() {
+    override fun onCreate(savedInstanceState: Bundle?) {
+        super.onCreate(savedInstanceState)
+        val binding = ActivityPrivacyPolicyBinding.inflate(layoutInflater)
+        setContentView(binding.root)
+        val encoded = Base64.encodeToString(markdownR.html.PRIVACY_md.toByteArray(), Base64.NO_PADDING)
+        binding.policy.loadData(encoded, "text/html", "base64")
+    }
+}
diff --git a/app/src/main/java/app/pachli/di/ActivitiesModule.kt b/app/src/main/java/app/pachli/di/ActivitiesModule.kt
index bf2f1a6aa..8285d818f 100644
--- a/app/src/main/java/app/pachli/di/ActivitiesModule.kt
+++ b/app/src/main/java/app/pachli/di/ActivitiesModule.kt
@@ -21,6 +21,7 @@ import app.pachli.EditProfileActivity
 import app.pachli.LicenseActivity
 import app.pachli.ListsActivity
 import app.pachli.MainActivity
+import app.pachli.PrivacyPolicyActivity
 import app.pachli.SplashActivity
 import app.pachli.StatusListActivity
 import app.pachli.TabPreferenceActivity
@@ -128,4 +129,7 @@ abstract class ActivitiesModule {
 
     @ContributesAndroidInjector
     abstract fun contributesEditFilterActivity(): EditFilterActivity
+
+    @ContributesAndroidInjector
+    abstract fun contributesPrivacyPolicyActivity(): PrivacyPolicyActivity
 }
diff --git a/app/src/main/res/layout/activity_about.xml b/app/src/main/res/layout/activity_about.xml
index 1c0d93ce2..07eb791c0 100644
--- a/app/src/main/res/layout/activity_about.xml
+++ b/app/src/main/res/layout/activity_about.xml
@@ -169,19 +169,18 @@
                     app:layout_constraintStart_toStartOf="@+id/aboutWebsiteInfoTextView"
                     app:layout_constraintTop_toBottomOf="@id/aboutWebsiteInfoTextView" />
 
-                <app.pachli.view.ClickableSpanTextView
+                <TextView
                     android:id="@+id/aboutPrivacyPolicyTextView"
                     android:layout_width="0dp"
                     android:layout_height="wrap_content"
                     android:layout_marginTop="24dp"
                     android:lineSpacingMultiplier="1.2"
                     android:text="@string/about_privacy_policy"
-                    android:textIsSelectable="true"
+                    android:textColor="?android:attr/textColorLink"
                     app:layout_constraintEnd_toEndOf="@+id/aboutWebsiteInfoTextView"
                     app:layout_constraintStart_toStartOf="@+id/aboutWebsiteInfoTextView"
                     app:layout_constraintTop_toBottomOf="@id/aboutBugsFeaturesInfoTextView" />
 
-
                 <Button
                     android:id="@+id/appProfileButton"
                     style="@style/AppButton"
diff --git a/app/src/main/res/layout/activity_privacy_policy.xml b/app/src/main/res/layout/activity_privacy_policy.xml
new file mode 100644
index 000000000..c0e569acd
--- /dev/null
+++ b/app/src/main/res/layout/activity_privacy_policy.xml
@@ -0,0 +1,21 @@
+<?xml version="1.0" encoding="utf-8"?><!--
+  ~ Copyright 2023 Pachli Association
+  ~
+  ~ This file is a part of Pachli.
+  ~
+  ~ This program is free software; you can redistribute it and/or modify it under the terms of the
+  ~ GNU General Public License as published by the Free Software Foundation; either version 3 of the
+  ~ License, or (at your option) any later version.
+  ~
+  ~ Pachli 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 General
+  ~ Public License for more details.
+  ~
+  ~ You should have received a copy of the GNU General Public License along with Pachli; if not,
+  ~ see <http://www.gnu.org/licenses>.
+  -->
+
+<WebView xmlns:android="http://schemas.android.com/apk/res/android"
+    android:id="@+id/policy"
+    android:layout_width="match_parent"
+    android:layout_height="match_parent" />
diff --git a/app/src/main/res/values/strings.xml b/app/src/main/res/values/strings.xml
index ed8a88533..6929167d2 100644
--- a/app/src/main/res/values/strings.xml
+++ b/app/src/main/res/values/strings.xml
@@ -418,7 +418,7 @@
          * the url can be changed to link to the localized version of the license.
     -->
     <string name="about_project_site">Project website: https://pachli.app</string>
-    <string name="about_privacy_policy">Privacy policy: https://github.com/pachli/pachli-android/blob/main/PRIVACY.md</string>
+    <string name="about_privacy_policy">Privacy policy</string>
     <string name="about_bug_feature_request_site">Bug reports &amp; feature requests:\nhttps://github.com/pachli/pachli-android/issues</string>
     <string name="about_pachli_account">Pachli\'s Profile</string>
 
diff --git a/plugins/markdown2resource/README.md b/plugins/markdown2resource/README.md
new file mode 100644
index 000000000..f629cee0d
--- /dev/null
+++ b/plugins/markdown2resource/README.md
@@ -0,0 +1,56 @@
+# markdown2resource-plugin
+
+## Synopsis
+
+Gradle plugin to convert one or more Markdown files to Java files with static constants where the Markdown has been converted to HTML. Similar (but not quite identical) to Android resources.
+
+## Example
+
+In `build.gradle`:
+
+```groovy
+// Install the plugin
+plugins {
+    id "app.pachli.plugins.markdown2resource"
+}
+
+// ...
+
+// Configure the files to be processed
+markdown2resource {
+    files = [ layout.projectDirectory.file('../PRIVACY.md') ]
+}
+```
+
+In code:
+
+```kotlin
+// Assume binding.privacyPolicy references a `WebView`
+
+// The generated string constant is in the `markdownR.html` package, named
+// `PRIVACY_md`. To load the content in to a WebView it must be converted to
+// base64
+val html = Base64.encodeToString(markdownR.html.PRIVACY_md.toByteArray(), Base64.NO_PADDING)
+binding.privacyPolicy.loadData(html, "text/html", "base64")
+```
+
+## Configuration
+
+The `markdown2resource` block supports the following options.
+
+`files` - a list of `RegularFile` in Markdown.
+
+`packageName` - the package name to use for the generated resources. Default is the `android.namespace` of the build variant.
+
+`resourceClassName` - the outer class name to use for the generated resources. Default is `markdownR`.
+
+`stringClassName` - the inner class name to use for the generated resources. Default is `html`.
+
+## Tasks
+
+The plugin creates N tasks, one for each configured build variant, named `markdown2resource${variant.name.capitalized()}`
+
+For example:
+
+1. You have defined `debug` and `release` build types, two tasks will be created, `markdown2resourceDebug` and `markdown2resourceRelease`.
+2. You have defined `debug` and `release` build types and `demo` and `full` product flavours, four tasks will be created, `markdown2resourceDemoDebug`, `markdown2resourceDemoRelease`, `markdown2resourceFullDebug`, `markdown2resourceFullRelease`.
diff --git a/plugins/markdown2resource/build.gradle.kts b/plugins/markdown2resource/build.gradle.kts
new file mode 100644
index 000000000..54850bd20
--- /dev/null
+++ b/plugins/markdown2resource/build.gradle.kts
@@ -0,0 +1,50 @@
+/*
+ * Copyright 2023 Pachli Association
+ *
+ * This file is a part of Pachli.
+ *
+ * This program is free software; you can redistribute it and/or modify it under the terms of the
+ * GNU General Public License as published by the Free Software Foundation; either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * Pachli 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 General
+ * Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along with Pachli; if not,
+ * see <http://www.gnu.org/licenses>.
+ */
+
+@Suppress("DSL_SCOPE_VIOLATION") // TODO: Remove once KTIJ-19369 is fixed
+plugins {
+    `java-gradle-plugin`
+    `maven-publish`
+    kotlin("jvm") version "1.9.10"
+}
+
+repositories {
+    google()
+    mavenCentral()
+}
+
+group = "app.pachli.plugins"
+version = "0.0.1"
+
+gradlePlugin {
+    plugins {
+        create("markdown2resource") {
+            id = "app.pachli.plugins.markdown2resource"
+            implementationClass = "app.pachli.plugins.markdown2resource.Markdown2ResourcePlugin"
+        }
+    }
+}
+
+dependencies {
+    implementation("com.android.tools.build:gradle:8.1.1")
+    implementation("org.jetbrains:markdown:0.5.0")
+    implementation("com.squareup:javapoet:1.12.1")
+}
+
+kotlin {
+    jvmToolchain(17)
+}
diff --git a/plugins/markdown2resource/src/main/kotlin/app/pachli/plugins/markdown2resource/Markdown2ResourcePlugin.kt b/plugins/markdown2resource/src/main/kotlin/app/pachli/plugins/markdown2resource/Markdown2ResourcePlugin.kt
new file mode 100644
index 000000000..ebe6eacd2
--- /dev/null
+++ b/plugins/markdown2resource/src/main/kotlin/app/pachli/plugins/markdown2resource/Markdown2ResourcePlugin.kt
@@ -0,0 +1,156 @@
+/*
+ * Copyright 2023 Pachli Association
+ *
+ * This file is a part of Pachli.
+ *
+ * This program is free software; you can redistribute it and/or modify it under the terms of the
+ * GNU General Public License as published by the Free Software Foundation; either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * Pachli 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 General
+ * Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along with Pachli; if not,
+ * see <http://www.gnu.org/licenses>.
+ */
+
+package app.pachli.plugins.markdown2resource
+
+import com.android.build.gradle.AppExtension
+import com.squareup.javapoet.FieldSpec
+import com.squareup.javapoet.JavaFile
+import com.squareup.javapoet.TypeSpec
+import org.gradle.api.DefaultTask
+import org.gradle.api.GradleException
+import org.gradle.api.Plugin
+import org.gradle.api.Project
+import org.gradle.api.file.DirectoryProperty
+import org.gradle.api.file.RegularFile
+import org.gradle.api.provider.ListProperty
+import org.gradle.api.provider.Property
+import org.gradle.api.tasks.Input
+import org.gradle.api.tasks.InputFiles
+import org.gradle.api.tasks.OutputDirectory
+import org.gradle.api.tasks.TaskAction
+import org.gradle.configurationcache.extensions.capitalized
+import org.intellij.markdown.flavours.gfm.GFMFlavourDescriptor
+import org.intellij.markdown.html.HtmlGenerator
+import org.intellij.markdown.parser.MarkdownParser
+import java.io.IOException
+import javax.lang.model.element.Modifier
+
+interface Markdown2ResourcePluginExtension {
+    /** List of files */
+    val files: ListProperty<RegularFile>
+
+    /** Class name for the generated resources. Default is "markdownR" */
+    val resourceClassName: Property<String>
+
+    /** Class name for the generated strings. Default is "html". */
+    val stringClassName: Property<String>
+
+    /**
+     * Package name for the generated class. Default is the value of the android.namespace
+     * property.
+     */
+    val packageName: Property<String>
+}
+
+abstract class Markdown2ResourceTask : DefaultTask() {
+    @get:InputFiles
+    abstract val files: ListProperty<RegularFile>
+
+    @get:Input
+    abstract val resourceClassName: Property<String>
+
+    @get:Input
+    abstract val stringClassName: Property<String>
+
+    @get:Input
+    abstract val packageName: Property<String>
+
+    @get:OutputDirectory
+    abstract val outputDir: DirectoryProperty
+
+    @TaskAction
+    fun execute() {
+        logger.info("outputDir: ${outputDir.get()}")
+
+        val resourceClass = createResourceClass(resourceClassName.get())!!
+        val stringClass = createStringClass(stringClassName.get())!!
+        val flavour = GFMFlavourDescriptor()
+
+        files.get().forEach { markdownFile ->
+            logger.info("Processing ${markdownFile.asFile.absoluteFile.name}")
+
+            val f = markdownFile.asFile.readText()
+            val parsedTree = MarkdownParser(flavour).buildMarkdownTreeFromString(f)
+            val html = HtmlGenerator(f, parsedTree, flavour).generateHtml()
+
+            val resourceName = markdownFile.asFile.absoluteFile.name.replace("""[./\\]""".toRegex(), "_", )
+            logger.info("  Resource name: ${resourceClassName.get()}.${stringClassName.get()}.$resourceName")
+
+            stringClass.addField(
+                FieldSpec.builder(String::class.java, resourceName)
+                    .addModifiers(Modifier.PUBLIC, Modifier.STATIC, Modifier.FINAL)
+                    .initializer("\$S", html)
+                    .build(),
+            )
+
+            resourceClass.addType(stringClass.build())
+        }
+
+        generateStringResourceFile(packageName.get(), resourceClass)
+    }
+
+    private fun createResourceClass(name: String): TypeSpec.Builder? {
+        return TypeSpec.classBuilder(name).addModifiers(Modifier.PUBLIC, Modifier.FINAL)
+    }
+
+    private fun createStringClass(name: String): TypeSpec.Builder? {
+        return TypeSpec.classBuilder(name).addModifiers(Modifier.PUBLIC, Modifier.STATIC, Modifier.FINAL)
+    }
+
+    private fun generateStringResourceFile(packageName: String, classBuilder: TypeSpec.Builder) {
+        val javaFile = JavaFile.builder(packageName, classBuilder.build()).build()
+        try {
+            javaFile.writeTo(outputDir.get().asFile)
+            logger.info(javaFile.toString())
+        } catch (e: IOException) {
+            e.printStackTrace()
+        }
+    }
+}
+
+class Markdown2ResourcePlugin : Plugin<Project> {
+    override fun apply(target: Project) {
+        val extension = target.extensions.create(
+            "markdown2resource",
+            Markdown2ResourcePluginExtension::class.java
+        )
+        extension.resourceClassName.convention("markdownR")
+        extension.stringClassName.convention("html")
+
+        target.extensions.findByType(AppExtension::class.java)?.let { appExtension ->
+            appExtension.applicationVariants.all { variant ->
+                val outputDir =
+                    target.layout.buildDirectory.dir("generated/source/${variant.name}")
+                val taskName = "markdown2resource${variant.name.capitalized()}"
+
+                extension.packageName.convention(variant.mergeResourcesProvider.get().namespace)
+
+                val task =
+                    target.tasks.register(taskName, Markdown2ResourceTask::class.java) { task ->
+                        task.files.set(extension.files)
+                        task.resourceClassName.set(extension.resourceClassName)
+                        task.stringClassName.set(extension.stringClassName)
+                        task.packageName.set(extension.packageName)
+                        task.outputDir.set(outputDir)
+                    }
+
+                variant.registerJavaGeneratingTask(task, outputDir.get().asFile)
+            }
+        } ?: throw GradleException("'android' configuration block not found")
+    }
+}
diff --git a/settings.gradle b/settings.gradle
index 59ea9f405..fe112d554 100644
--- a/settings.gradle
+++ b/settings.gradle
@@ -3,6 +3,8 @@ pluginManagement {
         google()
         gradlePluginPortal()
     }
+
+    includeBuild 'plugins/markdown2resource'
 }
 
 dependencyResolutionManagement {