[UX] Gesture manager: delete custom gestures and update menu (#4652)

Include a safety check to prevent rerecording an existing gesture.

Also extend the default set of gestures to include all of them, and add east south west north for refresh. (I've always thought small diagonal swipe to be rather awkward to trigger.)

See https://github.com/koreader/koreader/pull/4644#issuecomment-466743715 and https://github.com/koreader/koreader/issues/4651 regarding the menu update.

frontend/apps/reader/modules/readergesture.lua

@@ -4,6 +4,7 @@ local Device = require("device")
 local Event = require("ui/event")
 local Geom = require("ui/geometry")
 local GestureRange = require("ui/gesturerange")
+local InfoMessage = require("ui/widget/infomessage")
 local InputContainer = require("ui/widget/container/inputcontainer")
 local InputDialog = require("ui/widget/inputdialog")
 local LuaData = require("luadata")
@@ -19,6 +20,7 @@ local default_gesture = {
     short_diagonal_swipe = "full_refresh",
     multiswipe = "nothing", -- otherwise registerGesture() won't pick up on multiswipes
     multiswipe_west_east = "previous_location",
+    multiswipe_east_south_west_north = "full_refresh",
 }
 
 local ReaderGesture = InputContainer:new{
@@ -29,6 +31,22 @@ local custom_multiswipes_path = DataStorage:getSettingsDir().."/multiswipes.lua"
 local custom_multiswipes = LuaData:open(custom_multiswipes_path, { name = "MultiSwipes" })
 local custom_multiswipes_table = custom_multiswipes:readSetting("multiswipes")
 
+local default_multiswipes = {
+    "west east",
+    "east west",
+    "north south",
+    "south north",
+    "north west",
+    "north east",
+    "south west",
+    "south east",
+    "east north",
+    "west north",
+    "east south",
+    "west south",
+    "east south west north",
+}
+local multiswipes = {}
 local multiswipes_info_text = _([[
 Multiswipes allow you to perform complex gestures built up out of multiple straight swipes.]])
 
@@ -55,6 +73,15 @@ function ReaderGesture:initGesture()
     G_reader_settings:saveSetting(self.ges_mode, gesture_manager)
 end
 
+function ReaderGesture:genMultiswipeSubmenu()
+    return {
+        text = _("Multiswipe"),
+        sub_item_table = self:buildMultiswipeMenu(),
+        enabled_func = function() return self.multiswipes_enabled end,
+        separator = true,
+    }
+end
+
 function ReaderGesture:addToMainMenu(menu_items)
     menu_items.gesture = {
         text = _("Gesture manager"),
@@ -71,7 +98,7 @@ function ReaderGesture:addToMainMenu(menu_items)
             {
                 text = _("Multiswipe recorder"),
                 enabled_func = function() return self.multiswipes_enabled end,
-                callback = function()
+                callback = function(touchmenu_instance)
                     local multiswipe_recorder
                     multiswipe_recorder = InputDialog:new{
                         title = _("Multiswipe recorder"),
@@ -91,7 +118,21 @@ function ReaderGesture:addToMainMenu(menu_items)
                                         local recorded_multiswipe = multiswipe_recorder._raw_multiswipe
                                         if not recorded_multiswipe then return end
                                         logger.dbg("Multiswipe recorder detected:", recorded_multiswipe)
+
+                                        for k, multiswipe in pairs(multiswipes) do
+                                            if recorded_multiswipe == multiswipe then
+                                                UIManager:show(InfoMessage:new{
+                                                    text = _("Recorded multiswipe already exists."),
+                                                    show_icon = false,
+                                                    timeout = 5,
+                                                })
+                                                return
+                                            end
+                                        end
+
                                         custom_multiswipes:addTableItem("multiswipes", recorded_multiswipe)
+                                        -- TODO implement some nicer method in TouchMenu than this ugly hack for updating the menu
+                                        touchmenu_instance.item_table[3] = self:genMultiswipeSubmenu()
                                         UIManager:close(multiswipe_recorder)
                                     end,
                                 },
@@ -120,12 +161,8 @@ function ReaderGesture:addToMainMenu(menu_items)
                 end,
                 help_text = _("The number of possible multiswipe gestures is theoretically infinite. With the multiswipe recorder you can easily record your own."),
             },
-            {
-                text = _("Multiswipe"),
-                sub_item_table = self:buildMultiswipeMenu(),
-                enabled_func = function() return self.multiswipes_enabled end,
-                separator = true,
-            },
+            -- NB If this changes from position 3, also update the position of this menu in multigesture recorder callback
+            self:genMultiswipeSubmenu(),
             {
                 text = _("Tap bottom left corner"),
                 sub_item_table = self:buildMenu("tap_left_bottom_corner", default_gesture["tap_left_bottom_corner"]),
@@ -199,25 +236,19 @@ function ReaderGesture:buildMenu(ges, default)
     return return_menu
 end
 
-local multiswipes = {
-    "west east",
-    "east west",
-    "north south",
-    "south north",
-    "south west",
-    "south east",
-    "east south",
-    "west south",
-}
+function ReaderGesture:buildMultiswipeMenu()
+    local menu = {}
+    multiswipes = {}
 
-if custom_multiswipes_table then
-    for k, v in pairs(custom_multiswipes_table) do
+    for k, v in pairs(default_multiswipes) do
         table.insert(multiswipes, v)
     end
-end
 
-function ReaderGesture:buildMultiswipeMenu()
-    local menu = {}
+    if custom_multiswipes_table then
+        for k, v in pairs(custom_multiswipes_table) do
+            table.insert(multiswipes, v)
+        end
+    end
 
     for i=1, #multiswipes do
         local multiswipe = multiswipes[i]
@@ -227,6 +258,21 @@ function ReaderGesture:buildMultiswipeMenu()
         table.insert(menu, {
             text = friendly_multiswipe_name,
             sub_item_table = self:buildMenu(safe_multiswipe_name, default_action),
+            hold_callback = function(touchmenu_instance)
+                if i > #default_multiswipes then
+                    UIManager:show(ConfirmBox:new{
+                        text = T(_("Remove custom multiswipe %1?"), friendly_multiswipe_name),
+                        ok_text = _("Remove"),
+                        ok_callback = function()
+                            -- multiswipes are a combined table, first defaults, then custom
+                            -- so the right index is minus #defalt_multiswipes
+                            custom_multiswipes:removeTableItem("multiswipes", i-#default_multiswipes)
+                            touchmenu_instance.item_table = self:buildMultiswipeMenu()
+                            touchmenu_instance:updateItems()
+                        end,
+                    })
+                end
+            end,
         })
     end