Remove ReplacementSpan, display diffs using CharacterStyle

app/src/main/java/com/keylesspalace/tusky/components/viewthread/edits/ViewEditsAdapter.kt

@@ -1,8 +1,6 @@
 package com.keylesspalace.tusky.components.viewthread.edits
 
 import android.content.Context
-import android.graphics.Canvas
-import android.graphics.Paint
 import android.graphics.Typeface.DEFAULT_BOLD
 import android.graphics.drawable.ColorDrawable
 import android.graphics.drawable.Drawable
@@ -11,7 +9,9 @@ import android.text.Html
 import android.text.Spannable
 import android.text.SpannableStringBuilder
 import android.text.Spanned
-import android.text.style.ReplacementSpan
+import android.text.TextPaint
+import android.text.style.CharacterStyle
+import android.util.TypedValue
 import android.view.LayoutInflater
 import android.view.View
 import android.view.ViewGroup
@@ -33,11 +33,9 @@ import com.keylesspalace.tusky.util.aspectRatios
 import com.keylesspalace.tusky.util.decodeBlurHash
 import com.keylesspalace.tusky.util.emojify
 import com.keylesspalace.tusky.util.hide
-import com.keylesspalace.tusky.util.loadAvatar
 import com.keylesspalace.tusky.util.parseAsMastodonHtml
 import com.keylesspalace.tusky.util.setClickableText
 import com.keylesspalace.tusky.util.show
-import com.keylesspalace.tusky.util.unicodeWrap
 import com.keylesspalace.tusky.util.visible
 import com.keylesspalace.tusky.viewdata.toViewData
 import org.xml.sax.XMLReader
@@ -52,13 +50,28 @@ class ViewEditsAdapter(
 
     private val absoluteTimeFormatter = AbsoluteTimeFormatter()
 
+    /** Size of large text in this theme, in px */
+    var largeTextSizePx: Float = 0f
+
+    /** Size of medium text in this theme, in px */
+    var mediumTextSizePx: Float = 0f
+
     override fun onCreateViewHolder(
         parent: ViewGroup,
         viewType: Int
     ): BindingHolder<ItemStatusEditBinding> {
         val binding = ItemStatusEditBinding.inflate(LayoutInflater.from(parent.context), parent, false)
+
         binding.statusEditMediaPreview.clipToOutline = true
 
+        val typedValue = TypedValue()
+        val context = binding.root.context
+        val displayMetrics = context.resources.displayMetrics
+        context.theme.resolveAttribute(R.attr.status_text_large, typedValue, true)
+        largeTextSizePx = typedValue.getDimension(displayMetrics)
+        context.theme.resolveAttribute(R.attr.status_text_medium, typedValue, true)
+        mediumTextSizePx = typedValue.getDimension(displayMetrics)
+
         return BindingHolder(binding)
     }
 
@@ -69,24 +82,26 @@ class ViewEditsAdapter(
 
         val context = binding.root.context
 
-        val avatarRadius: Int = context.resources
-            .getDimensionPixelSize(R.dimen.avatar_radius_48dp)
-
-        loadAvatar(edit.account.avatar, binding.statusEditAvatar, avatarRadius, animateAvatars)
-
-        val infoStringRes = if (position == edits.size - 1) {
+        val infoStringRes = if (position == edits.lastIndex) {
             R.string.status_created_info
         } else {
             R.string.status_edit_info
         }
 
+        // Show the most recent version of the status using large text to make it clearer for
+        // the user, and for similarity with thread view.
+        val variableTextSize = if (position == edits.lastIndex) {
+            mediumTextSizePx
+        } else {
+            largeTextSizePx
+        }
+        binding.statusEditContentWarningDescription.setTextSize(TypedValue.COMPLEX_UNIT_PX, variableTextSize)
+        binding.statusEditContent.setTextSize(TypedValue.COMPLEX_UNIT_PX, variableTextSize)
+        binding.statusEditMediaSensitivity.setTextSize(TypedValue.COMPLEX_UNIT_PX, variableTextSize)
+
         val timestamp = absoluteTimeFormatter.format(edit.createdAt, false)
 
-        binding.statusEditInfo.text = context.getString(
-            infoStringRes,
-            edit.account.name.unicodeWrap(),
-            timestamp
-        ).emojify(edit.account.emojis, binding.statusEditInfo, animateEmojis)
+        binding.statusEditInfo.text = context.getString(infoStringRes, timestamp)
 
         if (edit.spoilerText.isEmpty()) {
             binding.statusEditContentWarningDescription.hide()
@@ -198,6 +213,11 @@ class ViewEditsAdapter(
     }
 
     override fun getItemCount() = edits.size
+
+    companion object {
+        private const val VIEW_TYPE_EDITS_NEWEST = 0
+        private const val VIEW_TYPE_EDITS = 1
+    }
 }
 
 /**
@@ -266,98 +286,31 @@ class TuskyTagHandler(val context: Context) : Html.TagHandler {
         }
     }
 
-    /**
-     * A span that draws text with additional padding at the start/end of the text. The padding
-     * is the width of [separator].
-     *
-     * Note: The separator string is not included in the final text, so it will not be included
-     * if the user cuts or copies the text.
-     */
-    open class LRPaddedSpan(val separator: String = " ") : ReplacementSpan() {
-        /** The width of the separator string, used as padding */
-        var paddingWidth = 0f
-
-        /** Measured width of the span */
-        var spanWidth = 0f
-
-        override fun getSize(
-            paint: Paint,
-            text: CharSequence?,
-            start: Int,
-            end: Int,
-            fm: Paint.FontMetricsInt?
-        ): Int {
-            paddingWidth = paint.measureText(separator, 0, separator.length)
-            spanWidth = (paddingWidth * 2) + paint.measureText(text, start, end)
-            return spanWidth.toInt()
-        }
-
-        override fun draw(
-            canvas: Canvas,
-            text: CharSequence?,
-            start: Int,
-            end: Int,
-            x: Float,
-            top: Int,
-            y: Int,
-            bottom: Int,
-            paint: Paint
-        ) {
-            canvas.drawText(text?.subSequence(start, end).toString(), x + paddingWidth, y.toFloat(), paint)
-        }
-    }
-
     /** Span that signifies deleted text */
-    class DeletedTextSpan(context: Context) : LRPaddedSpan() {
-        private val bgPaint = Paint()
-        val radius: Float
+    class DeletedTextSpan(context: Context) : CharacterStyle() {
+        private var bgColor: Int
 
         init {
-            bgPaint.color = context.getColor(R.color.view_edits_background_delete)
-            radius = context.resources.getDimension(R.dimen.lrPaddedSpanRadius)
+            bgColor = context.getColor(R.color.view_edits_background_delete)
         }
 
-        override fun draw(
-            canvas: Canvas,
-            text: CharSequence?,
-            start: Int,
-            end: Int,
-            x: Float,
-            top: Int,
-            y: Int,
-            bottom: Int,
-            paint: Paint
-        ) {
-            canvas.drawRoundRect(x, top.toFloat(), x + spanWidth, bottom.toFloat(), radius, radius, bgPaint)
-            paint.isStrikeThruText = true
-            super.draw(canvas, text, start, end, x, top, y, bottom, paint)
+        override fun updateDrawState(tp: TextPaint) {
+            tp.bgColor = bgColor
+            tp.isStrikeThruText = true
         }
     }
 
     /** Span that signifies inserted text */
-    class InsertedTextSpan(context: Context) : LRPaddedSpan() {
-        val bgPaint = Paint()
-        val radius: Float
+    class InsertedTextSpan(context: Context) : CharacterStyle() {
+        private var bgColor: Int
 
         init {
-            bgPaint.color = context.getColor(R.color.view_edits_background_insert)
-            radius = context.resources.getDimension(R.dimen.lrPaddedSpanRadius)
+            bgColor = context.getColor(R.color.view_edits_background_insert)
         }
 
-        override fun draw(
-            canvas: Canvas,
-            text: CharSequence?,
-            start: Int,
-            end: Int,
-            x: Float,
-            top: Int,
-            y: Int,
-            bottom: Int,
-            paint: Paint
-        ) {
-            canvas.drawRoundRect(x, top.toFloat(), x + spanWidth, bottom.toFloat(), radius, radius, bgPaint)
-            paint.typeface = DEFAULT_BOLD
-            super.draw(canvas, text, start, end, x, top, y, bottom, paint)
+        override fun updateDrawState(tp: TextPaint) {
+            tp.bgColor = bgColor
+            tp.typeface = DEFAULT_BOLD
         }
     }
 

app/src/main/java/com/keylesspalace/tusky/components/viewthread/edits/ViewEditsFragment.kt

@@ -37,13 +37,16 @@ import com.keylesspalace.tusky.BottomSheetActivity
 import com.keylesspalace.tusky.R
 import com.keylesspalace.tusky.StatusListActivity
 import com.keylesspalace.tusky.components.account.AccountActivity
-import com.keylesspalace.tusky.databinding.FragmentViewThreadBinding
+import com.keylesspalace.tusky.databinding.FragmentViewEditsBinding
 import com.keylesspalace.tusky.di.Injectable
 import com.keylesspalace.tusky.di.ViewModelFactory
 import com.keylesspalace.tusky.interfaces.LinkListener
 import com.keylesspalace.tusky.settings.PrefKeys
+import com.keylesspalace.tusky.util.emojify
 import com.keylesspalace.tusky.util.hide
+import com.keylesspalace.tusky.util.loadAvatar
 import com.keylesspalace.tusky.util.show
+import com.keylesspalace.tusky.util.unicodeWrap
 import com.keylesspalace.tusky.util.viewBinding
 import com.mikepenz.iconics.IconicsDrawable
 import com.mikepenz.iconics.typeface.library.googlematerial.GoogleMaterial
@@ -54,7 +57,7 @@ import java.io.IOException
 import javax.inject.Inject
 
 class ViewEditsFragment :
-    Fragment(R.layout.fragment_view_thread),
+    Fragment(R.layout.fragment_view_edits),
     LinkListener,
     OnRefreshListener,
     MenuProvider,
@@ -65,7 +68,7 @@ class ViewEditsFragment :
 
     private val viewModel: ViewEditsViewModel by viewModels { viewModelFactory }
 
-    private val binding by viewBinding(FragmentViewThreadBinding::bind)
+    private val binding by viewBinding(FragmentViewEditsBinding::bind)
 
     private lateinit var statusId: String
 
@@ -88,6 +91,7 @@ class ViewEditsFragment :
         val animateAvatars = preferences.getBoolean(PrefKeys.ANIMATE_GIF_AVATARS, false)
         val animateEmojis = preferences.getBoolean(PrefKeys.ANIMATE_CUSTOM_EMOJIS, false)
         val useBlurhash = preferences.getBoolean(PrefKeys.USE_BLURHASH, true)
+        val avatarRadius: Int = requireContext().resources.getDimensionPixelSize(R.dimen.avatar_radius_48dp)
 
         viewLifecycleOwner.lifecycleScope.launch {
             viewModel.uiState.collect { uiState ->
@@ -130,6 +134,15 @@ class ViewEditsFragment :
                             useBlurhash = useBlurhash,
                             listener = this@ViewEditsFragment
                         )
+
+                        // Focus on the most recent version
+                        (binding.recyclerView.layoutManager as LinearLayoutManager).scrollToPosition(0)
+
+                        val account = uiState.edits.first().account
+                        loadAvatar(account.avatar, binding.statusAvatar, avatarRadius, animateAvatars)
+
+                        binding.statusDisplayName.text = account.name.unicodeWrap().emojify(account.emojis, binding.statusDisplayName, animateEmojis)
+                        binding.statusUsername.text = account.username
                     }
                 }
             }

app/src/main/java/com/keylesspalace/tusky/components/viewthread/edits/ViewEditsViewModel.kt

@@ -98,10 +98,7 @@ class ViewEditsViewModel @Inject constructor(private val api: MastodonApi) : Vie
                                 if (i < sortedEdits.size - 1) {
                                     currentContent = previousContent
                                     previousContent = loader.load(
-                                        sortedEdits[i + 1].content.replace(
-                                            "<br>",
-                                            "<br/>"
-                                        )
+                                        sortedEdits[i + 1].content.replace("<br>", "<br/>")
                                     )
                                 }
                             }