feat: tap TimeAgo to toggle relative ↔ absolute timestamp

Every TimeAgo composable (Android NoteCompose timestamp, NormalTimeAgo,
ChatTimeAgo, ChatroomHeaderCompose last-message time) and every Desktop
timestamp Text (NoteCard, NotificationsScreen, ChatPane, ConversationListPane)
is now clickable and toggles to a scale-adjusted absolute date/time:

  - same day → time only (e.g. "14:32"), locale-aware
  - same year → "MMM dd, HH:mm"
  - older    → "MMM dd, yyyy"

State is hoisted per-call site via rememberSaveable so the toggle survives
scroll-induced disposal in lazy lists. Desktop call sites share a small
ToggleableTimeAgoText wrapper; Android keeps its existing composable shapes
and just gains a clickable modifier + state.

https://claude.ai/code/session_01AuPon9VQeRfKV1BTVQuKGC

amethyst/src/main/java/com/vitorpamplona/amethyst/ui/note/TimeAgoFormatter.kt

@@ -21,11 +21,14 @@
 package com.vitorpamplona.amethyst.ui.note
 
 import android.content.Context
+import android.text.format.DateFormat
 import android.text.format.DateUtils
 import com.vitorpamplona.amethyst.R
 import com.vitorpamplona.amethyst.ui.stringRes
 import com.vitorpamplona.quartz.utils.TimeUtils
 import java.text.SimpleDateFormat
+import java.util.Calendar
+import java.util.Date
 import java.util.Locale
 import kotlin.math.round
 
@@ -42,6 +45,51 @@ var monthFormatter = SimpleDateFormat(MONTH_DATE_FORMAT, locale)
 var yearNoDayFormatter = SimpleDateFormat(YEAR_NO_DAY_DATE_FORMAT, locale)
 var monthNoDayFormatter = SimpleDateFormat(MONTH_NO_DAY_DATE_FORMAT, locale)
 
+/**
+ * Formats a Unix timestamp (seconds) as an absolute date/time string, picking the
+ * granularity from how far away the timestamp is:
+ *   - same day → time only (e.g. "14:32" / "2:32 PM", locale-aware)
+ *   - same year → "MMM dd, HH:mm"
+ *   - older    → "MMM dd, yyyy"
+ *
+ * Used by [com.vitorpamplona.amethyst.ui.note.elements.TimeAgo] when the user
+ * taps the relative timestamp to reveal the absolute one.
+ */
+fun timeAbsolute(
+    time: Long?,
+    context: Context,
+    prefix: String = " • ",
+): String {
+    if (time == null) return " "
+    if (time == 0L) return prefix + stringRes(context, R.string.never)
+
+    if (locale != Locale.getDefault()) {
+        locale = Locale.getDefault()
+        yearFormatter = SimpleDateFormat(YEAR_DATE_FORMAT, locale)
+        monthFormatter = SimpleDateFormat(MONTH_DATE_FORMAT, locale)
+    }
+
+    val timeMs = time * 1000
+    val now = Calendar.getInstance()
+    val then = Calendar.getInstance().apply { timeInMillis = timeMs }
+
+    val sameYear = now.get(Calendar.YEAR) == then.get(Calendar.YEAR)
+    val sameDay = sameYear && now.get(Calendar.DAY_OF_YEAR) == then.get(Calendar.DAY_OF_YEAR)
+
+    val timeOfDay = DateFormat.getTimeFormat(context).format(Date(timeMs))
+
+    return when {
+        sameDay -> prefix + timeOfDay
+        sameYear -> prefix + monthFormatter.format(timeMs) + ", " + timeOfDay
+        else -> prefix + yearFormatter.format(timeMs)
+    }
+}
+
+fun timeAbsoluteNoDot(
+    time: Long?,
+    context: Context,
+): String = timeAbsolute(time, context, prefix = "")
+
 fun timeAgo(
     time: Long?,
     context: Context,

amethyst/src/main/java/com/vitorpamplona/amethyst/ui/note/elements/TimeAgo.kt

@@ -20,17 +20,24 @@
  */
 package com.vitorpamplona.amethyst.ui.note.elements
 
+import androidx.compose.foundation.clickable
+import androidx.compose.foundation.interaction.MutableInteractionSource
 import androidx.compose.material3.MaterialTheme
 import androidx.compose.material3.Text
 import androidx.compose.runtime.Composable
 import androidx.compose.runtime.derivedStateOf
 import androidx.compose.runtime.getValue
+import androidx.compose.runtime.mutableStateOf
 import androidx.compose.runtime.remember
+import androidx.compose.runtime.saveable.rememberSaveable
+import androidx.compose.runtime.setValue
 import androidx.compose.ui.Modifier
 import androidx.compose.ui.platform.LocalContext
 import androidx.compose.ui.text.style.TextOverflow
 import com.vitorpamplona.amethyst.R
 import com.vitorpamplona.amethyst.model.Note
+import com.vitorpamplona.amethyst.ui.note.timeAbsolute
+import com.vitorpamplona.amethyst.ui.note.timeAbsoluteNoDot
 import com.vitorpamplona.amethyst.ui.note.timeAgo
 import com.vitorpamplona.amethyst.ui.note.timeAgoShort
 import com.vitorpamplona.amethyst.ui.stringRes
@@ -48,11 +55,14 @@ fun TimeAgo(time: Long) {
     // Subscribe to the shared coarse ticker; `derivedStateOf` ensures the Text only
     // recomposes when the formatted string actually flips (e.g. 1m → 2m), not on every tick.
     val nowState = LocalNowSeconds.current
+    var showAbsolute by rememberSaveable(time) { mutableStateOf(false) }
+    val interactionSource = remember { MutableInteractionSource() }
+
     val timeStr by
         remember(time, context, nowState) {
             derivedStateOf {
                 nowState.value
-                timeAgo(time, context = context)
+                if (showAbsolute) timeAbsolute(time, context) else timeAgo(time, context = context)
             }
         }
 
@@ -60,6 +70,11 @@ fun TimeAgo(time: Long) {
         text = timeStr,
         color = MaterialTheme.colorScheme.placeholderText,
         maxLines = 1,
+        modifier =
+            Modifier.clickable(
+                interactionSource = interactionSource,
+                indication = null,
+            ) { showAbsolute = !showAbsolute },
     )
 }
 
@@ -70,12 +85,16 @@ fun NormalTimeAgo(
 ) {
     val nowStr = stringRes(id = R.string.now)
     val nowState = LocalNowSeconds.current
+    val context = LocalContext.current
+    var showAbsolute by rememberSaveable(baseNote.idHex) { mutableStateOf(false) }
+    val interactionSource = remember { MutableInteractionSource() }
 
     val time by
         remember(baseNote, nowStr, nowState) {
             derivedStateOf {
                 nowState.value
-                timeAgoShort(baseNote.createdAt() ?: 0L, nowStr)
+                val createdAt = baseNote.createdAt() ?: 0L
+                if (showAbsolute) timeAbsoluteNoDot(createdAt, context) else timeAgoShort(createdAt, nowStr)
             }
         }
 
@@ -83,6 +102,10 @@ fun NormalTimeAgo(
         text = time,
         maxLines = 1,
         overflow = TextOverflow.Ellipsis,
-        modifier = modifier,
+        modifier =
+            modifier.clickable(
+                interactionSource = interactionSource,
+                indication = null,
+            ) { showAbsolute = !showAbsolute },
     )
 }

amethyst/src/main/java/com/vitorpamplona/amethyst/ui/screen/loggedIn/chats/feed/ChatTimeAgo.kt

@@ -20,6 +20,8 @@
  */
 package com.vitorpamplona.amethyst.ui.screen.loggedIn.chats.feed
 
+import androidx.compose.foundation.clickable
+import androidx.compose.foundation.interaction.MutableInteractionSource
 import androidx.compose.foundation.layout.Row
 import androidx.compose.foundation.layout.Spacer
 import androidx.compose.foundation.layout.size
@@ -28,7 +30,10 @@ import androidx.compose.material3.Text
 import androidx.compose.runtime.Composable
 import androidx.compose.runtime.derivedStateOf
 import androidx.compose.runtime.getValue
+import androidx.compose.runtime.mutableStateOf
 import androidx.compose.runtime.remember
+import androidx.compose.runtime.saveable.rememberSaveable
+import androidx.compose.runtime.setValue
 import androidx.compose.ui.Alignment
 import androidx.compose.ui.Modifier
 import androidx.compose.ui.platform.LocalContext
@@ -38,6 +43,7 @@ import com.vitorpamplona.amethyst.commons.icons.symbols.Icon
 import com.vitorpamplona.amethyst.commons.icons.symbols.MaterialSymbols
 import com.vitorpamplona.amethyst.model.Note
 import com.vitorpamplona.amethyst.ui.note.elements.LocalNowSeconds
+import com.vitorpamplona.amethyst.ui.note.timeAbsoluteNoDot
 import com.vitorpamplona.amethyst.ui.note.timeAgoShort
 import com.vitorpamplona.amethyst.ui.note.timeAheadNoDot
 import com.vitorpamplona.amethyst.ui.stringRes
@@ -50,11 +56,16 @@ import com.vitorpamplona.quartz.nip40Expiration.expiration
 fun ChatTimeAgo(baseNote: Note) {
     val nowStr = stringRes(id = R.string.now)
     val nowState = LocalNowSeconds.current
+    val context = LocalContext.current
+    var showAbsolute by rememberSaveable(baseNote.idHex) { mutableStateOf(false) }
+    val interactionSource = remember { MutableInteractionSource() }
+
     val time by
         remember(baseNote, nowStr, nowState) {
             derivedStateOf {
                 nowState.value
-                timeAgoShort(baseNote.createdAt() ?: 0L, nowStr)
+                val createdAt = baseNote.createdAt() ?: 0L
+                if (showAbsolute) timeAbsoluteNoDot(createdAt, context) else timeAgoShort(createdAt, nowStr)
             }
         }
 
@@ -63,6 +74,11 @@ fun ChatTimeAgo(baseNote: Note) {
         color = MaterialTheme.colorScheme.placeholderText,
         fontSize = Font12SP,
         maxLines = 1,
+        modifier =
+            Modifier.clickable(
+                interactionSource = interactionSource,
+                indication = null,
+            ) { showAbsolute = !showAbsolute },
     )
 }
 

amethyst/src/main/java/com/vitorpamplona/amethyst/ui/screen/loggedIn/chats/rooms/ChatroomHeaderCompose.kt

@@ -20,6 +20,8 @@
  */
 package com.vitorpamplona.amethyst.ui.screen.loggedIn.chats.rooms
 
+import androidx.compose.foundation.clickable
+import androidx.compose.foundation.interaction.MutableInteractionSource
 import androidx.compose.foundation.layout.Box
 import androidx.compose.foundation.layout.Spacer
 import androidx.compose.material3.LocalTextStyle
@@ -31,6 +33,7 @@ import androidx.compose.runtime.derivedStateOf
 import androidx.compose.runtime.getValue
 import androidx.compose.runtime.mutableStateOf
 import androidx.compose.runtime.remember
+import androidx.compose.runtime.saveable.rememberSaveable
 import androidx.compose.runtime.setValue
 import androidx.compose.ui.Modifier
 import androidx.compose.ui.platform.LocalContext
@@ -62,6 +65,7 @@ import com.vitorpamplona.amethyst.ui.note.LoadPublicChatChannel
 import com.vitorpamplona.amethyst.ui.note.NonClickableUserPictures
 import com.vitorpamplona.amethyst.ui.note.ObserveDraftEvent
 import com.vitorpamplona.amethyst.ui.note.elements.LocalNowSeconds
+import com.vitorpamplona.amethyst.ui.note.timeAbsolute
 import com.vitorpamplona.amethyst.ui.note.timeAgo
 import com.vitorpamplona.amethyst.ui.screen.loggedIn.AccountViewModel
 import com.vitorpamplona.amethyst.ui.screen.loggedIn.chats.privateDM.header.RoomNameDisplay
@@ -486,17 +490,24 @@ private fun TimeAgo(channelLastTime: Long?) {
 
     val context = LocalContext.current
     val nowState = LocalNowSeconds.current
+    var showAbsolute by rememberSaveable(channelLastTime) { mutableStateOf(false) }
+    val interactionSource = remember { MutableInteractionSource() }
     val timeAgo by
         remember(channelLastTime, context, nowState) {
             derivedStateOf {
                 nowState.value
-                timeAgo(channelLastTime, context)
+                if (showAbsolute) timeAbsolute(channelLastTime, context) else timeAgo(channelLastTime, context)
             }
         }
     Text(
         text = timeAgo,
         color = MaterialTheme.colorScheme.grayText,
         maxLines = 1,
+        modifier =
+            Modifier.clickable(
+                interactionSource = interactionSource,
+                indication = null,
+            ) { showAbsolute = !showAbsolute },
     )
 }