Another round of ReaderFooter fixes (#6830)

* When auto_refresh_time is enabled, don't actually refresh anything when the footer is hidden.
* Fix a bunch of state tracking related to height computations, meaning `getHeight()` is now actually accurate, always, and we don't need shitty workarounds anymore.
  * `footer_container.dimen.h` *includes* the progress bar, so, never reset it to 0 unless the progress bar is disabled (some `settings.progress_bar_position` codepaths were mistakenly doing just that).
  * More aggressively set/reset `footer_text.height` (not sure this one makes much of a difference, and/or if it's actually useful at all, but, the tracking was already there, but hella inconsistent, so, just fix it).
* Honor `settings.reclaim_height` in other bits of code that were only checking `footer_visible` to figure out the visible page area.
* Ask ReaderView to update the `visible_area` *now* when toggling the footer's visibility (for ReaderPaging).

frontend/apps/reader/modules/readerfooter.lua

@@ -461,6 +461,7 @@ function ReaderFooter:init()
     }
     -- all width related values will be initialized in self:resetLayout()
     self.text_width = 0
+    self.footer_text.height = 0
     self.progress_bar = ProgressWidget:new{
         width = nil,
         height = nil,
@@ -491,8 +492,10 @@ function ReaderFooter:init()
         self.view.footer_visible = (self.mode ~= self.mode_list.off)
         self:updateFooterTextGenerator()
         if self.settings.progress_bar_position and self.has_no_mode then
-            self.footer_container.dimen.h = 0
             self.footer_text.height = 0
+            if self.settings.disable_progress_bar then
+                self.footer_container.dimen.h = 0
+            end
         end
     else
         self:applyFooterMode()
@@ -500,6 +503,8 @@ function ReaderFooter:init()
     if self.settings.auto_refresh_time then
         self:setupAutoRefreshTime()
     end
+
+    self.visibility_change = nil
 end
 
 function ReaderFooter:updateFooterContainer()
@@ -581,7 +586,10 @@ function ReaderFooter:setupAutoRefreshTime()
         self.autoRefreshTime = function()
             -- Only actually repaint the footer if nothing's being shown over ReaderUI (#6616)
             if UIManager:getTopWidget() == "ReaderUI" then
-                self:onUpdateFooter(true)
+                -- And that only if it's actually visible
+                if self.view.footer_visible then
+                    self:onUpdateFooter(true)
+                end
             else
                 logger.dbg("Skipping ReaderFooter repaint, because ReaderUI is not the top-level widget")
                 -- NOTE: We *do* keep its content up-to-date, though
@@ -666,6 +674,8 @@ end
 
 function ReaderFooter:getHeight()
     if self.footer_content then
+        -- NOTE: self.footer_content is self.vertical_frame + self.bottom_padding,
+        --       self.vertical_frame includes self.text_container (which includes self.footer_text)
         return self.footer_content:getSize().h
     else
         return 0
@@ -805,7 +815,9 @@ function ReaderFooter:addToMainMenu(menu_items)
                 self.reclaim_height = self.settings.reclaim_height or false
                 -- refresh margins position
                 if self.has_no_mode then
-                    self.footer_container.dimen.h = 0
+                    if self.settings.disable_progress_bar then
+                        self.footer_container.dimen.h = 0
+                    end
                     self.footer_text.height = 0
                     should_signal = true
                     self.genFooterText = footerTextGeneratorMap.empty
@@ -1777,22 +1789,27 @@ function ReaderFooter:_updateFooterText(force_repaint, force_recompute)
             self.footer_text.height = 0
         else
             self.text_width = self.footer_text:getSize().w
+            self.footer_text.height = self.footer_text:getSize().h
         end
         self.progress_bar.width = 0
     elseif self.settings.progress_bar_position then
-        if text == "" then
-            self.footer_container.dimen.h = 0
+        if self.has_no_mode or text == "" then
+            self.text_width = 0
             self.footer_text.height = 0
+        else
+            self.text_width = self.footer_text:getSize().w
+            self.footer_text.height = self.footer_text:getSize().h
         end
         self.progress_bar.width = math.floor(self._saved_screen_width - 2 * self.settings.progress_margin_width)
-        self.text_width = self.footer_text:getSize().w
     else
         if self.has_no_mode or text == "" then
             self.text_width = 0
+            self.footer_text.height = 0
         else
             local text_max_available_ratio = (100 - self.settings.progress_bar_min_width_pct) / 100
             self.footer_text:setMaxWidth(math.floor(text_max_available_ratio * self._saved_screen_width - 2 * self.settings.progress_margin_width))
             self.text_width = self.footer_text:getSize().w + self.text_left_margin
+            self.footer_text.height = self.footer_text:getSize().h
         end
         self.progress_bar.width = math.floor(
             self._saved_screen_width - self.text_width - self.settings.progress_margin_width*2)
@@ -1815,19 +1832,21 @@ function ReaderFooter:_updateFooterText(force_repaint, force_recompute)
     -- NOTE: That's assuming using "fast" for pans was a good idea, which, it turned out, not so much ;).
     -- NOTE: We skip repaints on page turns/pos update, as that's redundant (and slow).
     if force_repaint then
+        -- If there was a visibility change, notify ReaderView
+        if self.visibility_change then
+            self.ui:handleEvent(Event:new("ReaderFooterVisibilityChange"))
+            self.visibility_change = nil
+        end
+
         -- NOTE: Getting the dimensions of the widget is impossible without having drawn it first,
         --       so, we'll fudge it if need be...
+        --       i.e., when it's no longer visible, because there's nothing to draw ;).
         local refresh_dim = self.footer_content.dimen
-        -- No content yet...
-        if not refresh_dim then
-            -- So, instead, compute self.footer_content's height ourselves: i.e., self.vertical_frame + self.bottom_padding...
+        -- No more content...
+        if not self.view.footer_visible and not refresh_dim then
+            -- So, instead, rely on self:getHeight to compute self.footer_content's height early...
             refresh_dim = self.dimen
-            if self.view.footer_visible then
-                refresh_dim.h = self.vertical_frame:getSize().h + self.bottom_padding
-            else
-                -- When going invisible, the text is no longer visible, so the frame's height is off by self.height
-                refresh_dim.h = self.vertical_frame:getSize().h + self.height + self.bottom_padding
-            end
+            refresh_dim.h = self:getHeight()
             refresh_dim.y = self._saved_screen_height - refresh_dim.h
         end
         -- If we're making the footer visible (or it already is), we don't need to repaint ReaderUI behind it
@@ -1835,11 +1854,13 @@ function ReaderFooter:_updateFooterText(force_repaint, force_recompute)
             -- Unfortunately, it's not a modal (we never show() it), so it's not in the window stack,
             -- instead, it's baked inside ReaderUI, so it gets slightly trickier...
             -- NOTE: self.view.footer -> self ;).
-            UIManager:setDirty(self.view.footer, function()
-                return "ui", refresh_dim
-            end)
+
             -- c.f., ReaderView:paintTo()
             UIManager:widgetRepaint(self.view.footer, 0, 0)
+            -- We've painted it first to ensure self.footer_content.dimen is sane
+            UIManager:setDirty(self.view.footer, function()
+                return "ui", self.footer_content.dimen
+            end)
         else
             UIManager:setDirty(self.view.dialog, function()
                 return "ui", refresh_dim
@@ -1944,6 +1965,8 @@ function ReaderFooter:applyFooterMode(mode)
         self:updateFooterContainer()
         -- NOTE: _updateFooterText does a resetLayout, but not a forced one!
         self:resetLayout(true)
+        -- Flag _updateFooterText to notify ReaderView to recalculate the visible_area!
+        self.visibility_change = true
     end
 end
 

frontend/apps/reader/modules/readerpagemap.lua

@@ -133,7 +133,7 @@ function ReaderPageMap:updateVisibleLabels()
     end
     self.container:clear()
     local page_labels = self.ui.document:getPageMapVisiblePageLabels()
-    local footer_height = (self.view.footer_visible and 1 or 0) * self.view.footer:getHeight()
+    local footer_height = ((self.view.footer_visible and not self.view.footer.settings.reclaim_height) and 1 or 0) * self.view.footer:getHeight()
     local max_y = Screen:getHeight() - footer_height
     local last_label_bottom_y = 0
     for _, page in ipairs(page_labels) do

frontend/apps/reader/modules/readerrolling.lua

@@ -693,7 +693,7 @@ end
 function ReaderRolling:onGotoViewRel(diff)
     logger.dbg("goto relative screen:", diff, ", in mode: ", self.view.view_mode)
     if self.view.view_mode == "scroll" then
-        local footer_height = (self.view.footer_visible and 1 or 0) * self.view.footer:getHeight()
+        local footer_height = ((self.view.footer_visible and not self.view.footer.settings.reclaim_height) and 1 or 0) * self.view.footer:getHeight()
         local page_visible_height = self.ui.dimen.h - footer_height
         local pan_diff = diff * page_visible_height
         if self.show_overlap_enable then
@@ -869,7 +869,7 @@ function ReaderRolling:_gotoPos(new_pos, do_dim_area)
     if new_pos > max_pos then new_pos = max_pos end
     -- adjust dim_area according to new_pos
     if self.view.view_mode ~= "page" and self.show_overlap_enable and do_dim_area then
-        local footer_height = (self.view.footer_visible and 1 or 0) * self.view.footer:getHeight()
+        local footer_height = ((self.view.footer_visible and not self.view.footer.settings.reclaim_height) and 1 or 0) * self.view.footer:getHeight()
         local page_visible_height = self.ui.dimen.h - footer_height
         local panned_step = new_pos - self.current_pos
         self.view.dim_area.x = 0

frontend/apps/reader/modules/readerview.lua

@@ -568,7 +568,7 @@ function ReaderView:recalculate()
             self.state.rotation)
         -- reset our size
         self.visible_area:setSizeTo(self.dimen)
-        if self.ui.view.footer_visible then
+        if self.ui.view.footer_visible and not self.ui.view.footer.settings.reclaim_height then
             self.visible_area.h = self.visible_area.h - self.ui.view.footer:getHeight()
         end
         if self.ui.document.configurable.writing_direction == 0 then
@@ -594,7 +594,7 @@ function ReaderView:recalculate()
     end
     self.state.offset = Geom:new{x = 0, y = 0}
     if self.dimen.h > self.visible_area.h then
-        if self.ui.view.footer_visible then
+        if self.ui.view.footer_visible and not self.ui.view.footer.settings.reclaim_height then
             self.state.offset.y = (self.dimen.h - (self.visible_area.h + self.ui.view.footer:getHeight())) / 2
         else
             self.state.offset.y = (self.dimen.h - self.visible_area.h) / 2
@@ -603,7 +603,7 @@ function ReaderView:recalculate()
     if self.dimen.w > self.visible_area.w then
         self.state.offset.x = (self.dimen.w - self.visible_area.w) / 2
     end
-    -- flag a repaint so self:paintTo will be called
+    -- Flag a repaint so self:paintTo will be called
     -- NOTE: This is also unfortunately called during panning, essentially making sure we'll never be using "fast" for pans ;).
     UIManager:setDirty(self.dialog, "partial")
 end
@@ -791,6 +791,25 @@ function ReaderView:onRotationUpdate(rotation)
     self:recalculate()
 end
 
+function ReaderView:onReaderFooterVisibilityChange()
+    -- Don't bother ReaderRolling with this nonsense, the footer's height is NOT handled via visible_area there ;)
+    if self.ui.document.info.has_pages and self.state.page then
+        -- NOTE: Simply relying on recalculate would be a wee bit too much: it'd reset the in-page offsets,
+        --       which would be wrong, and is also not necessary, since the footer is at the bottom of the screen ;).
+        --       So, simply mangle visible_area's height ourselves...
+        if not self.ui.view.footer.settings.reclaim_height then
+            -- NOTE: Yes, this means that toggling reclaim_height requires a page switch (for a proper recalculate).
+            --       Thankfully, most of the time, the quirks are barely noticeable ;).
+            if self.ui.view.footer_visible then
+                self.visible_area.h = self.visible_area.h - self.ui.view.footer:getHeight()
+            else
+                self.visible_area.h = self.visible_area.h + self.ui.view.footer:getHeight()
+            end
+        end
+        self.ui:handleEvent(Event:new("ViewRecalculate", self.visible_area, self.page_area))
+    end
+end
+
 function ReaderView:onGammaUpdate(gamma)
     self.state.gamma = gamma
     if self.page_scroll then

frontend/apps/reader/modules/readerzooming.lua

@@ -263,7 +263,7 @@ function ReaderZooming:getZoom(pageno)
     -- calculate zoom value:
     local zoom_w = self.dimen.w
     local zoom_h = self.dimen.h
-    if self.ui.view.footer_visible then
+    if self.ui.view.footer_visible and not self.ui.view.footer.settings.reclaim_height then
         zoom_h = zoom_h - self.ui.view.footer:getHeight()
     end
     if self.rotation % 180 == 0 then