feat: open a conversation on its first unread message, under a "New" line

Both UIs: a channel, DM or room with unread messages opens on the oldest of them (MessageHistory::firstUnreadChannel / firstUnreadDm, own messages not counted), a "New" line above it, so it reads down to the newest. Nothing unread: the newest, as before. L1: the first unread is selected and scrolled up top with the line in view; the channel's unread count now counts down as you read towards the newest. L2: the page holding it, scrolled to the line; an incoming message scrolls down only when the list is already at its end. Sim hooks: sim_unread (L1), sim_open("unread") (L2). Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
2026-11-02 10:51:57 +00:00 · 2026-10-08 22:20:04 +02:00
parent 5e87686183
commit aaf35351d7
8 changed files with 271 additions and 63 deletions
@@ -47,7 +47,8 @@ class MessagesScreen : public UIScreen {
  int _hist_sel, _hist_scroll;
  FullscreenMsgView _fs;
  int  _unread_at_entry;    // channel unread count when entering CHANNEL_HIST
-  int  _viewing_max_seen;  // highest _hist_sel reached in current session
+  int  _unread_base = 0;    // messages filed since: the unread are indices base.. base+count-1
+  int  _seen_lo = 0, _seen_hi = -1;   // the indices shown so far this session

  // KEYBOARD
  KeyboardWidget* _kb;
@@ -143,6 +144,11 @@ class MessagesScreen : public UIScreen {
  int _dm_hist_sel, _dm_hist_scroll;
  FullscreenMsgView _dm_fs;

+  // "New" over the first message unread when the conversation opened (index
+  // as _hist_sel / _dm_hist_sel, -1: none); the first render scrolls it up top.
+  int  _new_idx = -1;
+  bool _anchor_new = false;
+
  int _hist_visible = 2;  // updated in render(); for history list scroll clamping

  void expandMsg(const char* tmpl, char* out, int out_len) const {   // ui-core/MessageText.h
@@ -681,7 +687,6 @@ class MessagesScreen : public UIScreen {
      // Filed at index 0 by sendText(): the unread index range is stale, and
      // the user is active in this channel -- fully read.
      _unread_at_entry = 0;
-      _viewing_max_seen = 0;
    } else {
      _dm_hist_sel = 0;
      _dm_hist_scroll = 0;
@@ -969,7 +974,7 @@ public:
      _sel_channel_idx(0), _sending_to_channel(false),
      _msg_sel(0), _msg_scroll(0), _active_msg_count(0),
      _hist_sel(0), _hist_scroll(0),
-      _unread_at_entry(0), _viewing_max_seen(0),
+      _unread_at_entry(0),
      _history(task->core().history),
      _dm_hist_sel(-1), _dm_hist_scroll(0),
      _ctx_dirty(false), _pin_picker_active(false), _direct_entry(false), _reply_mode(false),
@@ -1003,8 +1008,14 @@ public:
    return _phase == DM_HIST && memcmp(_sel_contact.id.pub_key, pub_key, 4) == 0;
  }
  void onViewedHistoryGrew(bool channel) {
-    if (channel) { if (_hist_sel > 0)    { _hist_sel++; _hist_scroll++; } }
-    else         { if (_dm_hist_sel > 0) { _dm_hist_sel++; _dm_hist_scroll++; } }
+    if (channel) {
+      if (_hist_sel > 0) { _hist_sel++; _hist_scroll++; }
+      _unread_base++;
+      if (_seen_hi >= 0) { _seen_lo++; _seen_hi++; }
+    } else {
+      if (_dm_hist_sel > 0) { _dm_hist_sel++; _dm_hist_scroll++; }
+    }
+    if (_new_idx >= 0) _new_idx++;
  }

  // Room logins (who is logged in this session, the saved passwords, the one
@@ -1037,11 +1048,56 @@ public:
  // the scroll/selection view state. Shared by the Enter-on-contact path and the
  // post-login auto-enter.
  void openDmHistory() {
-    _task->clearDMUnread(_sel_contact.id.pub_key);
-    _dm_hist_sel = -1;
+    beginDmView();
+    _phase = DM_HIST;
+  }
+
+  // Opening a conversation: on its first unread message ("New" above it), else
+  // on the compose row under the newest.
+  void beginDmView() {
+    const uint8_t* key = _sel_contact.id.pub_key;
+    _new_idx = _history.firstUnreadDm(key, _task->getDMUnread(key));
+    _anchor_new = _new_idx >= 0;
+    _task->clearDMUnread(key);
+    _dm_hist_sel = _new_idx;
    _dm_hist_scroll = 0;
    _dm_fs.active = false;
-    _phase = DM_HIST;
+  }
+  void beginChannelView(uint8_t channel_idx) {
+    _sel_channel_idx = channel_idx;
+    _unread_at_entry = (int)_history.chUnread(channel_idx);
+    _unread_base = 0;
+    _seen_lo = 0; _seen_hi = -1;
+    _new_idx = _history.firstUnreadChannel(channel_idx, _unread_at_entry);
+    _anchor_new = _new_idx >= 0;
+    _hist_scroll = 0;
+    _hist_sel = _new_idx >= 0 ? _new_idx : _history.histCountForChannel(channel_idx) > 0 ? 0 : -1;
+    _fs.active = false;
+  }
+
+  // On the first unread (sel), opening: the scroll showing it highest with
+  // "New" above it (stack(s) lays out from s, sets div_y when "New" fits).
+  template <class Stack> static int anchorScroll(Stack stack, const int& div_y, int sel, int count) {
+    int pick = -1;
+    for (int s = sel > 8 ? sel - 8 : 0; s <= sel; s++) {
+      int n = stack(s);
+      if (s + n - 1 < sel) continue;
+      if (div_y >= 0 || sel + 1 >= count) return s;
+      if (pick < 0) pick = s;
+    }
+    return pick >= 0 ? pick : sel;
+  }
+
+  // "New" between two lines, lh tall, over the first message unread on opening.
+  static void drawNewDivider(DisplayDriver& d, int y, int w, int lh) {
+    const char* t = "New";
+    int tw = d.getTextWidth(t);
+    int tx = (w - tw) / 2, mid = y + lh / 2;
+    d.setColor(DisplayDriver::LIGHT);
+    d.fillRect(1, mid, tx - 4, 1);
+    d.fillRect(tx + tw + 3, mid, w - 1 - (tx + tw + 3), 1);
+    d.setCursor(tx, y + 1);
+    d.print(t);
  }


@@ -1070,15 +1126,21 @@ public:
  // "what has the user seen on screen" logic is pure phase-machine state.
  void updateChannelUnread() {
    if (_sel_channel_idx < 0 || _sel_channel_idx >= MAX_GROUP_CHANNELS) return;
-    // histEntryForChannel is newest-first: index 0 = newest (unread), higher = older.
-    // Count everything actually rendered on screen as seen — not just the
-    // highlighted row — so a taller screen that fits more boxes at once marks
-    // more read up front, instead of requiring a press per row.
-    int seen_to = _hist_scroll + _hist_visible - 1;
-    if (_hist_sel > seen_to) seen_to = _hist_sel;
-    if (seen_to > _viewing_max_seen) _viewing_max_seen = seen_to;
-    // Each step down from 0 sees one more message; seen count = max_seen + 1.
-    int remaining = _unread_at_entry - (_viewing_max_seen + 1);
+    // histEntryForChannel is newest-first: index 0 = newest, higher = older;
+    // the unread from opening are _unread_base onwards. Count everything
+    // actually rendered on screen as seen — not just the highlighted row — so
+    // a taller screen that fits more boxes at once marks more read up front,
+    // instead of requiring a press per row. Reading starts at the first unread
+    // and goes down to the newest, so what's been shown is one stretch.
+    int lo = _hist_scroll, hi = _hist_scroll + _hist_visible - 1;
+    if (_hist_sel >= 0 && _hist_sel < lo) lo = _hist_sel;
+    if (_hist_sel > hi) hi = _hist_sel;
+    if (_seen_hi < 0 || lo < _seen_lo) _seen_lo = lo;
+    if (hi > _seen_hi) _seen_hi = hi;
+    int a = _seen_lo > _unread_base ? _seen_lo : _unread_base;
+    int b = _unread_base + _unread_at_entry - 1;
+    if (_seen_hi < b) b = _seen_hi;
+    int remaining = _unread_at_entry - (b >= a ? b - a + 1 : 0);
    _history.setChUnread(_sel_channel_idx, (uint8_t)(remaining > 0 ? remaining : 0));
  }

@@ -1109,7 +1171,8 @@ public:
    _pick_fav_slot = -1;
    _direct_entry = false;
    _unread_at_entry = 0;
-    _viewing_max_seen = 0;
+    _new_idx = -1;
+    _anchor_new = false;
    _ch_view.reset();
    _ch_view_pending_rebuild = false;
  }
@@ -1235,10 +1298,7 @@ public:

  void enterDM(const ContactInfo& ci) {
    _sel_contact = ci;
-    _task->clearDMUnread(ci.id.pub_key);
-    _dm_hist_sel = -1;
-    _dm_hist_scroll = 0;
-    _dm_fs.active = false;
+    beginDmView();
    _room_mode = false;
    _phase = DM_HIST;
    _direct_entry = true;
@@ -1249,10 +1309,7 @@ public:
  // to. Caller must have already reset() the screen.
  void enterRoom(const ContactInfo& ci) {
    _sel_contact = ci;
-    _task->clearDMUnread(ci.id.pub_key);
-    _dm_hist_sel = -1;
-    _dm_hist_scroll = 0;
-    _dm_fs.active = false;
+    beginDmView();
    _room_mode = true;
    _phase = DM_HIST;
    _direct_entry = true;
@@ -1262,12 +1319,7 @@ public:
  // Open a channel's history directly (used by the Favourites dial). Caller
  // must have already reset() the screen.
  void enterChannel(uint8_t channel_idx) {
-    _sel_channel_idx = channel_idx;
-    _unread_at_entry = (int)_history.chUnread(channel_idx);
-    _hist_scroll = 0;
-    _hist_sel = _history.histCountForChannel(channel_idx) > 0 ? 0 : -1;
-    _viewing_max_seen = _hist_sel >= 0 ? _hist_sel : 0;
-    _fs.active = false;
+    beginChannelView(channel_idx);
    _phase = CHANNEL_HIST;
    _direct_entry = true;
  }
@@ -1503,7 +1555,8 @@ public:
      // Fixed-track scrollbar metrics + a stable gutter reserve (decided by a
      // whole-list fit test, not last frame's visible count) so message boxes
      // don't reflow their width as messages arrive.
-      HistScroll hs = compact_dm
+      auto scrollMetrics = [&]() {
+        return compact_dm
          ? computeHistScrollH(display, dm_count, _dm_hist_scroll, hist_start_y, cby, 1, compactH)
          : computeHistScroll(display, expand, dm_count, _dm_hist_scroll,
          hist_start_y, cby, lh,
@@ -1514,20 +1567,24 @@ public:
            char tmp_sender[33];
            return bodyAt(idx, tmp_sender, sizeof(tmp_sender));
          });
+      };
+      HistScroll hs = scrollMetrics();
      int reserve = hs.reserve;
-      {
-        // Stack boxes upward from just above the compose row, so item 0 (the
-        // newest message) lands at the bottom of the list and older messages
-        // sit progressively higher — same anchor convention as a typical
-        // messenger, instead of newest-at-top. box_ys[i] still corresponds
-        // to item (_dm_hist_scroll + i), same as before; only its y flips.
+      int div_y = -1;   // "New", when shown
+      // Stack boxes upward from just above the compose row, so item 0 (the
+      // newest message) lands at the bottom of the list and older messages
+      // sit progressively higher — same anchor convention as a typical
+      // messenger, instead of newest-at-top. box_ys[i] still corresponds
+      // to item (s + i), same as before; only its y flips.
+      auto stack = [&](int s) {
        const int fixed_bh = 2 * lh + 1;
        const int box_gap = expand ? 2 : 1;
        int cur_y = cby - box_gap;   // reserve the same gap against compose as between boxes
-        for (int ii = 0; ii < MAX_VIS_BOXES && (_dm_hist_scroll + ii) < dm_count; ii++) {
-          int bh = compact_dm ? compactH(_dm_hist_scroll + ii, reserve) : fixed_bh;
+        n_vis = 0; div_y = -1;
+        for (int ii = 0; ii < MAX_VIS_BOXES && (s + ii) < dm_count; ii++) {
+          int bh = compact_dm ? compactH(s + ii, reserve) : fixed_bh;
          if (expand) {
-            int rp = _history.dmHistEntryForContact(_sel_contact.id.pub_key, _dm_hist_scroll + ii);
+            int rp = _history.dmHistEntryForContact(_sel_contact.id.pub_key, s + ii);
            if (rp >= 0) {
              char hsb[33];
              const char* hbody = skipReplyPrefix(dmDisplayParts(_history.dmAtPos(rp), is_room, filtered_name, hsb, sizeof(hsb)));
@@ -1538,8 +1595,20 @@ public:
          if (box_top < hist_start_y) break;
          box_ys[n_vis] = box_top; box_hs[n_vis] = bh; n_vis++;
          cur_y = box_top - box_gap;
+          if (s + ii == _new_idx && _new_idx + 1 < dm_count) {   // "New" over it, below the older ones
+            if (cur_y - lh < hist_start_y) break;
+            div_y = cur_y - lh;
+            cur_y = div_y - box_gap;
+          }
        }
+        return n_vis;
+      };
+      if (_anchor_new) {
+        _anchor_new = false;
+        _dm_hist_scroll = anchorScroll(stack, div_y, _dm_hist_sel, dm_count);
+        hs = scrollMetrics();
      }
+      stack(_dm_hist_scroll);
      _hist_visible = n_vis;
      for (int i = 0; i < n_vis && (_dm_hist_scroll + i) < dm_count; i++) {
        int item = _dm_hist_scroll + i;
@@ -1614,6 +1683,8 @@ public:
        drawHeadedBubble(display, y, bh, lh, sel, reserve, e.outgoing, sender, body, age, mark, expand, mq_delay);
      }

+      if (div_y >= 0) drawNewDivider(display, div_y, display.width() - reserve, lh);
+
      if (dm_count == 0) {
        display.setColor(DisplayDriver::LIGHT);
        display.drawTextCentered(display.width()/2, display.height()/2, "No messages yet");
@@ -1705,7 +1776,8 @@ public:
      const int MAX_VIS_BOXES = 8;
      int box_ys[MAX_VIS_BOXES], box_hs[MAX_VIS_BOXES], n_vis = 0;
      // Fixed-track scrollbar metrics + stable gutter reserve (see DM history above).
-      HistScroll hs = computeHistScroll(display, expand, ch_hist_count, _hist_scroll,
+      auto scrollMetrics = [&]() {
+        return computeHistScroll(display, expand, ch_hist_count, _hist_scroll,
          hist_start_y, cby, lh,
          [&](int idx) -> const char* {
            int rp = _history.histEntryForChannel(_sel_channel_idx, idx);
@@ -1714,18 +1786,22 @@ public:
            const char* s = strstr(t, ": ");
            return skipReplyPrefix(s ? s + 2 : t);
          });
+      };
+      HistScroll hs = scrollMetrics();
      int reserve = hs.reserve;
-      {
-        // Stack boxes upward from just above the compose row — see the DM
-        // history block above for why (newest at the bottom, like a typical
-        // messenger). box_ys[i] still corresponds to item (_hist_scroll + i).
+      int div_y = -1;   // "New", when shown
+      // Stack boxes upward from just above the compose row — see the DM
+      // history block above for why (newest at the bottom, like a typical
+      // messenger). box_ys[i] still corresponds to item (s + i).
+      auto stack = [&](int s) {
        const int fixed_bh = 2 * lh + 1;
        const int box_gap = expand ? 2 : 1;
        int cur_y = cby - box_gap;   // reserve the same gap against compose as between boxes
-        for (int ii = 0; ii < MAX_VIS_BOXES && (_hist_scroll + ii) < ch_hist_count; ii++) {
+        n_vis = 0; div_y = -1;
+        for (int ii = 0; ii < MAX_VIS_BOXES && (s + ii) < ch_hist_count; ii++) {
          int bh = fixed_bh;
          if (expand) {
-            int rp = _history.histEntryForChannel(_sel_channel_idx, _hist_scroll + ii);
+            int rp = _history.histEntryForChannel(_sel_channel_idx, s + ii);
            if (rp >= 0) {
              const char* rtext = _history.chAtPos(rp).text;
              const char* rsep = strstr(rtext, ": ");
@@ -1737,8 +1813,20 @@ public:
          if (box_top < hist_start_y) break;
          box_ys[n_vis] = box_top; box_hs[n_vis] = bh; n_vis++;
          cur_y = box_top - box_gap;
+          if (s + ii == _new_idx && _new_idx + 1 < ch_hist_count) {   // "New" over it, below the older ones
+            if (cur_y - lh < hist_start_y) break;
+            div_y = cur_y - lh;
+            cur_y = div_y - box_gap;
+          }
        }
+        return n_vis;
+      };
+      if (_anchor_new) {
+        _anchor_new = false;
+        _hist_scroll = anchorScroll(stack, div_y, _hist_sel, ch_hist_count);
+        hs = scrollMetrics();
      }
+      stack(_hist_scroll);
      _hist_visible = n_vis;
      updateChannelUnread();  // mark everything in the just-computed visible window as seen

@@ -1784,6 +1872,8 @@ public:
        drawHeadedBubble(display, y, bh, lh, sel, reserve, outgoing, sender, body, age, mark, expand, mq_delay);
      }

+      if (div_y >= 0) drawNewDivider(display, div_y, display.width() - reserve, lh);
+
      if (ch_hist_count == 0) {
        display.setColor(DisplayDriver::LIGHT);
        display.drawTextCentered(display.width()/2, display.height()/2, "No messages yet");
@@ -2200,16 +2290,12 @@ public:
        if (_pick_target) { commitPickTargetChannel(_sel_channel_idx); return true; }
        if (_pick_fav_slot >= 0) { commitPickFavChannel(_sel_channel_idx); return true; }
        if (_pick_bot_channel) { commitPickBotChannel(_sel_channel_idx); return true; }
-        int hc = _history.histCountForChannel(_sel_channel_idx);
-        _unread_at_entry = (int)_history.chUnread(_sel_channel_idx);
-        _hist_scroll = 0;
-        _hist_sel = hc > 0 ? 0 : -1;
-        _viewing_max_seen = _hist_sel >= 0 ? _hist_sel : 0;
+        beginChannelView(_sel_channel_idx);
        _phase = CHANNEL_HIST;
        // Not updateChannelUnread() here: _hist_visible is still whatever this
        // channel's first render() hasn't computed yet (stale, shared with
-        // DM_HIST) — calling it now could ratchet _viewing_max_seen past what's
-        // actually about to be shown. render() calls it once that's fresh.
+        // DM_HIST) — calling it now could mark more seen than is about to be
+        // shown. render() calls it once that's fresh.
        if (_share_mode) beginShareCompose(true);
        return true;
      }
@@ -2210,6 +2210,17 @@ void UITask::simMessage(const char* text) {
  onMessageArrived(ev);
 }

+// Sim tests: read and new messages (UiCore::simUnreadDemo), then channel 0
+// (which 0) or the first chat contact (1) opened as from the list.
+void UITask::simUnread(int which) {
+  if (which < 0) { _core->simUnreadDemo(); return; }
+  if (which == 0) { openChannelHistory(0); return; }
+  for (int i = 0; i < the_mesh.getNumContacts(); i++) {
+    ContactInfo c;
+    if (the_mesh.getContactByIdx(MAX_ANON_CONTACTS + i, c) && c.type == ADV_TYPE_CHAT) { openContactDM(c); return; }
+  }
+}
+
 void UITask::simCompose(const char* text) {
  gotoMessagesScreen();
  ((MessagesScreen*)messages_screen)->simCompose(text);
@@ -2716,6 +2727,11 @@ extern "C" EMSCRIPTEN_KEEPALIVE void sim_compose(const char* text) {
  if (g_sim_ui_task_for_js) g_sim_ui_task_for_js->simCompose(text);
 }

+// Sim tests: -1 files read and new messages, 0 opens channel 0, 1 the first DM.
+extern "C" EMSCRIPTEN_KEEPALIVE void sim_unread(int which) {
+  if (g_sim_ui_task_for_js) g_sim_ui_task_for_js->simUnread(which);
+}
+
 // Sim tests: a channel message arrives, alerted in Settings > Message alert's
 // style (0 Normal, 1 Compact, 2 Off).
 extern "C" EMSCRIPTEN_KEEPALIVE void sim_message(const char* text, int style) {
@@ -284,6 +284,7 @@ public:
 #ifdef SIM_PLATFORM
  void simCompose(const char* text);   // sim tests: a channel post's keyboard holding `text`
  void simMessage(const char* text);   // sim tests: a channel message arrives
+  void simUnread(int which);           // sim tests: read and new messages, opened
 #endif
  void openContactDM(const ContactInfo& ci);
  void openChannelHistory(uint8_t channel_idx);   // Favourites dial: open a pinned channel