Added missing chapters count in MangaInfoHeader (#9184)

* Added missing chapters count in MangaInfoHeader

* Added "Might be missing chapters"

* Added missing chapters to MangaAndSourceTitlesLarge function

* Removed comments

* Reworked getMissingChapters to countMissingChapters, moved -1 check

* Attempting detecting sub-chapters

* Moved MissingChapters to ChapterHeader; Adapted design to fit in

* Fixed block comment in one-line-element

* Fixed critical missing-chapter counting bug

* Undid unintentional & unnecessary changes

* Moved & refactored countMissingChapters

* Fixed import order; Mapping chapter object to chapterNumber

* Optimized "No (valid) chapters" detection

---------

Co-authored-by: arkon <arkon@users.noreply.github.com>

app/src/main/java/eu/kanade/presentation/manga/MangaScreen.kt

@@ -65,6 +65,7 @@ import eu.kanade.tachiyomi.ui.manga.chapterDecimalFormat
 import eu.kanade.tachiyomi.util.lang.toRelativeString
 import eu.kanade.tachiyomi.util.system.copyToClipboard
 import tachiyomi.domain.chapter.model.Chapter
+import tachiyomi.domain.chapter.service.countMissingChapters
 import tachiyomi.domain.manga.model.Manga
 import tachiyomi.domain.source.model.StubSource
 import tachiyomi.presentation.core.components.LazyColumn
@@ -393,6 +394,7 @@ private fun MangaScreenSmallImpl(
                         ChapterHeader(
                             enabled = chapters.fastAll { !it.selected },
                             chapterCount = chapters.size,
+                            missingChapters = countMissingChapters(chapters.map { it.chapter.chapterNumber }),
                             onClick = onFilterClicked,
                         )
                     }
@@ -604,6 +606,7 @@ fun MangaScreenLargeImpl(
                                 ChapterHeader(
                                     enabled = chapters.fastAll { !it.selected },
                                     chapterCount = chapters.size,
+                                    missingChapters = countMissingChapters(chapters.map { it.chapter.chapterNumber }),
                                     onClick = onFilterButtonClicked,
                                 )
                             }

app/src/main/java/eu/kanade/presentation/manga/components/ChapterHeader.kt

@@ -4,6 +4,9 @@ import androidx.compose.foundation.clickable
 import androidx.compose.foundation.layout.Row
 import androidx.compose.foundation.layout.fillMaxWidth
 import androidx.compose.foundation.layout.padding
+import androidx.compose.material3.AssistChip
+import androidx.compose.material3.AssistChipDefaults.assistChipColors
+import androidx.compose.material3.AssistChipDefaults.assistChipElevation
 import androidx.compose.material3.MaterialTheme
 import androidx.compose.material3.Text
 import androidx.compose.runtime.Composable
@@ -11,6 +14,7 @@ import androidx.compose.ui.Alignment
 import androidx.compose.ui.Modifier
 import androidx.compose.ui.res.pluralStringResource
 import androidx.compose.ui.res.stringResource
+import androidx.compose.ui.text.style.TextOverflow
 import androidx.compose.ui.unit.dp
 import eu.kanade.tachiyomi.R
 
@@ -18,6 +22,7 @@ import eu.kanade.tachiyomi.R
 fun ChapterHeader(
     enabled: Boolean,
     chapterCount: Int?,
+    missingChapters: Int?,
     onClick: () -> Unit,
 ) {
     Row(
@@ -40,5 +45,42 @@ fun ChapterHeader(
             modifier = Modifier.weight(1f),
             color = MaterialTheme.colorScheme.onBackground,
         )
+
+        // Missing chapters
+        if (missingChapters == null) {
+            DrawWarning(
+                text = stringResource(R.string.missing_chapters_unknown),
+            )
+        } else if (missingChapters > 0) {
+            DrawWarning(
+                text = pluralStringResource(
+                    id = R.plurals.missing_chapters,
+                    count = missingChapters,
+                    missingChapters,
+                ),
+            )
+        }
     }
 }
+
+@Composable
+private fun DrawWarning(text: String) {
+    AssistChip(
+        onClick = {
+            // TODO Show missing chapters
+        },
+        label = {
+            Text(
+                text = text,
+                overflow = TextOverflow.Ellipsis,
+                color = MaterialTheme.colorScheme.primary,
+            )
+        },
+        shape = MaterialTheme.shapes.small,
+        border = null,
+        colors = assistChipColors(
+            containerColor = MaterialTheme.colorScheme.surface,
+        ),
+        elevation = assistChipElevation(1.dp),
+    )
+}