Manga description adjustments (#6011)

* Manga description adjustments

- Animated state changes
- Adjust scrim position to fully show 2 lines when shrunk
- Set minLines to avoid scrim hiding oneliner

* Change icon and adjust animation

* Revert fancy scrim animation

app/src/main/java/eu/kanade/tachiyomi/widget/MangaSummaryView.kt

@@ -0,0 +1,188 @@
+package eu.kanade.tachiyomi.widget
+
+import android.animation.AnimatorSet
+import android.animation.ValueAnimator
+import android.content.Context
+import android.graphics.drawable.Animatable
+import android.util.AttributeSet
+import android.view.LayoutInflater
+import android.widget.FrameLayout
+import androidx.annotation.AttrRes
+import androidx.annotation.StyleRes
+import androidx.constraintlayout.widget.ConstraintLayout
+import androidx.core.content.ContextCompat
+import androidx.core.view.doOnNextLayout
+import androidx.core.view.isVisible
+import androidx.core.view.updateLayoutParams
+import androidx.interpolator.view.animation.FastOutSlowInInterpolator
+import eu.kanade.tachiyomi.R
+import eu.kanade.tachiyomi.databinding.MangaSummaryBinding
+import eu.kanade.tachiyomi.util.system.animatorDurationScale
+import eu.kanade.tachiyomi.util.system.copyToClipboard
+import eu.kanade.tachiyomi.util.view.setChips
+import kotlin.math.roundToInt
+import kotlin.math.roundToLong
+
+class MangaSummaryView @JvmOverloads constructor(
+    context: Context,
+    attrs: AttributeSet? = null,
+    @AttrRes defStyleAttr: Int = 0,
+    @StyleRes defStyleRes: Int = 0
+) : FrameLayout(context, attrs, defStyleAttr, defStyleRes) {
+
+    private val binding = MangaSummaryBinding.inflate(LayoutInflater.from(context), this, true)
+
+    private var animatorSet: AnimatorSet? = null
+
+    private var recalculateHeights = false
+    private var descExpandedHeight = -1
+    private var descShrunkHeight = -1
+
+    var expanded = false
+        set(value) {
+            if (field != value) {
+                field = value
+                updateExpandState()
+            }
+        }
+
+    var description: CharSequence? = null
+        set(value) {
+            if (field != value) {
+                field = if (value.isNullOrBlank()) {
+                    context.getString(R.string.unknown)
+                } else {
+                    value
+                }
+                binding.descriptionText.text = field
+                recalculateHeights = true
+                doOnNextLayout {
+                    updateExpandState()
+                }
+                requestLayout()
+            }
+        }
+
+    fun setTags(items: List<String>?, onClick: (item: String) -> Unit) {
+        binding.tagChipsShrunk.setChips(items, onClick)
+        binding.tagChipsExpanded.setChips(items, onClick)
+    }
+
+    private fun updateExpandState() = binding.apply {
+        val initialSetup = descriptionText.maxHeight < 0
+
+        val maxHeightTarget = if (expanded) descExpandedHeight else descShrunkHeight
+        val maxHeightStart = if (initialSetup) maxHeightTarget else descriptionText.maxHeight
+        val descMaxHeightAnimator = ValueAnimator().apply {
+            setIntValues(maxHeightStart, maxHeightTarget)
+            addUpdateListener {
+                descriptionText.maxHeight = it.animatedValue as Int
+            }
+        }
+
+        val toggleDrawable = ContextCompat.getDrawable(
+            context,
+            if (expanded) R.drawable.anim_caret_up else R.drawable.anim_caret_down
+        )
+        toggleMore.setImageDrawable(toggleDrawable)
+
+        var pastHalf = false
+        val toggleTarget = if (expanded) 1F else 0F
+        val toggleStart = if (initialSetup) {
+            toggleTarget
+        } else {
+            toggleMore.translationY / toggleMore.height
+        }
+        val toggleAnimator = ValueAnimator().apply {
+            setFloatValues(toggleStart, toggleTarget)
+            addUpdateListener {
+                val value = it.animatedValue as Float
+
+                toggleMore.translationY = toggleMore.height * value
+                descriptionScrim.translationY = toggleMore.translationY
+                toggleMoreScrim.translationY = toggleMore.translationY
+                tagChipsShrunkContainer.updateLayoutParams<ConstraintLayout.LayoutParams> {
+                    topMargin = toggleMore.translationY.roundToInt()
+                }
+                tagChipsExpanded.updateLayoutParams<ConstraintLayout.LayoutParams> {
+                    topMargin = toggleMore.translationY.roundToInt()
+                }
+
+                // Update non-animatable objects mid-animation makes it feel less abrupt
+                if (it.animatedFraction >= 0.5F && !pastHalf) {
+                    pastHalf = true
+                    descriptionText.text = trimWhenNeeded(description)
+                    tagChipsShrunkContainer.scrollX = 0
+                    tagChipsShrunkContainer.isVisible = !expanded
+                    tagChipsExpanded.isVisible = expanded
+                }
+            }
+        }
+
+        animatorSet?.cancel()
+        animatorSet = AnimatorSet().apply {
+            interpolator = FastOutSlowInInterpolator()
+            duration = (TOGGLE_ANIM_DURATION * context.animatorDurationScale).roundToLong()
+            playTogether(toggleAnimator, descMaxHeightAnimator)
+            start()
+        }
+        (toggleDrawable as? Animatable)?.start()
+    }
+
+    private fun trimWhenNeeded(text: CharSequence?): CharSequence? {
+        return if (!expanded) {
+            text
+                ?.replace(Regex(" +\$", setOf(RegexOption.MULTILINE)), "")
+                ?.replace(Regex("[\\r\\n]{2,}", setOf(RegexOption.MULTILINE)), "\n")
+        } else {
+            text
+        }
+    }
+
+    override fun onMeasure(widthMeasureSpec: Int, heightMeasureSpec: Int) {
+        if (!recalculateHeights) {
+            super.onMeasure(widthMeasureSpec, heightMeasureSpec)
+            return
+        }
+        recalculateHeights = false
+
+        // Measure with expanded lines
+        binding.descriptionText.maxLines = Int.MAX_VALUE
+        super.onMeasure(widthMeasureSpec, heightMeasureSpec)
+        descExpandedHeight = binding.descriptionText.measuredHeight
+
+        // Measure with shrunk lines
+        binding.descriptionText.maxLines = SHRUNK_DESC_MAX_LINES
+        super.onMeasure(widthMeasureSpec, heightMeasureSpec)
+        descShrunkHeight = binding.descriptionText.measuredHeight
+    }
+
+    init {
+        binding.descriptionText.apply {
+            // So that 1 line of text won't be hidden by scrim
+            minLines = DESC_MIN_LINES
+
+            setOnLongClickListener {
+                context.copyToClipboard(
+                    context.getString(R.string.description),
+                    text.toString()
+                )
+                true
+            }
+        }
+
+        arrayOf(
+            binding.descriptionText,
+            binding.descriptionScrim,
+            binding.toggleMoreScrim,
+            binding.toggleMore
+        ).forEach {
+            it.setOnClickListener { expanded = !expanded }
+        }
+    }
+}
+
+private const val TOGGLE_ANIM_DURATION = 300L
+
+private const val DESC_MIN_LINES = 2
+private const val SHRUNK_DESC_MAX_LINES = 3