add kobo frontlight gesture (#2284)

* add kobo frontlight gesture

frontend/apps/reader/modules/readerkobolight.lua

@@ -0,0 +1,126 @@
+local InputContainer = require("ui/widget/container/inputcontainer")
+local LeftContainer = require("ui/widget/container/leftcontainer")
+local GestureRange = require("ui/gesturerange")
+local Device = require("device")
+local Geom = require("ui/geometry")
+local Screen = Device.screen
+local DEBUG = require("dbg")
+local UIManager = require("ui/uimanager")
+local Notification = require("ui/widget/notification")
+local T = require("ffi/util").template
+local _ = require("gettext")
+
+local DTAP_ZONE_KOBOLIGHTTOGGLE = {x = 0, y = 0.9375, w = 0.1, h = 0.0625 }
+local DTAP_ZONE_KOBOLIGHTSWIPE = {x = 0, y = 0.125, w = 0.1, h = 0.875 }
+
+local ReaderKoboLight = InputContainer:new{
+    steps = {0,1,1,1,1,2,2,2,3,4,5,6,7,8,9,10},
+    gestureScale = Screen:getHeight() * DTAP_ZONE_KOBOLIGHTSWIPE.h * 0.8,
+}
+
+function ReaderKoboLight:init()
+    self[1] = LeftContainer:new{
+        dimen = Geom:new{w = Screen:getWidth(), h = Screen:getHeight()},
+    }
+    self:resetLayout()
+end
+
+function ReaderKoboLight:resetLayout()
+    local new_screen_width = Screen:getWidth()
+    if new_screen_width == self[1].dimen.w then return end
+    local new_screen_height = Screen:getHeight()
+    self[1].dimen.w = new_screen_width
+    self[1].dimen.h = new_screen_height
+    self.gestureScale = new_screen_height * DTAP_ZONE_KOBOLIGHTSWIPE.h * 0.8
+
+    if Device:isTouchDevice() then
+        self.ges_events = {
+            Tap = {
+                GestureRange:new{
+                    ges = "tap",
+                    range = Geom:new{
+                        x = new_screen_width*DTAP_ZONE_KOBOLIGHTTOGGLE.x,
+                        y = new_screen_height*DTAP_ZONE_KOBOLIGHTTOGGLE.y,
+                        w = new_screen_width*DTAP_ZONE_KOBOLIGHTTOGGLE.w,
+                        h = new_screen_height*DTAP_ZONE_KOBOLIGHTTOGGLE.h
+                    }
+                }
+            },
+            Swipe = {
+                GestureRange:new{
+                    ges = "swipe",
+                    range = Geom:new{
+                        x = new_screen_width*DTAP_ZONE_KOBOLIGHTSWIPE.x,
+                        y = new_screen_height*DTAP_ZONE_KOBOLIGHTSWIPE.y,
+                        w = new_screen_width*DTAP_ZONE_KOBOLIGHTSWIPE.w,
+                        h = new_screen_height*DTAP_ZONE_KOBOLIGHTSWIPE.h
+                    }
+                }
+            }
+        }
+    end
+end
+
+function ReaderKoboLight:onShowIntensity()
+    local powerd = Device:getPowerDevice()
+    if powerd.fl_intensity ~= nil then
+        UIManager:show(Notification:new{
+            text = T(_("Frontlight intensity is set to %1."), powerd.fl_intensity),
+            timeout = 1.0,
+        })
+    end
+    return true
+end
+
+function ReaderKoboLight:onShowOnOff()
+    local powerd = Device:getPowerDevice()
+    local new_text
+    if powerd.is_fl_on then
+        new_text = _("Frontlight is on.")
+    else
+        new_text = _("Frontlight is off.")
+    end
+    UIManager:show(Notification:new{
+            text = new_text,
+            timeout = 1.0,
+        })
+    return true
+end
+
+function ReaderKoboLight:onTap()
+    Device:getPowerDevice():toggleFrontlight()
+    self:onShowOnOff()
+    return true
+end
+
+function ReaderKoboLight:onSwipe(arg, ges)
+    local powerd = Device:getPowerDevice()
+    if powerd.fl_intensity == nil then return true end
+
+    DEBUG("frontlight intensity", powerd.fl_intensity)
+    local step = math.ceil(#self.steps * ges.distance / self.gestureScale)
+    DEBUG("step = ", step)
+    local delta_int = self.steps[step] or self.steps[#self.steps]
+    DEBUG("delta_int = ", delta_int)
+    local new_intensity
+    if ges.direction == "north" then
+        new_intensity = powerd.fl_intensity + delta_int
+    elseif ges.direction == "south" then
+        new_intensity = powerd.fl_intensity - delta_int
+    end
+    if new_intensity ~= nil then
+        -- when new_intensity <=0, toggle light off
+        if new_intensity <=0 then
+            if powerd.is_fl_on then
+                powerd:toggleFrontlight()
+            end
+            self:onShowOnOff()
+        else    -- general case
+            powerd:setIntensity(new_intensity)
+            self:onShowIntensity()
+        end
+    end
+    return true
+end
+
+return ReaderKoboLight

frontend/apps/reader/modules/readerview.lua

@@ -5,12 +5,14 @@ local ReaderDogear = require("apps/reader/modules/readerdogear")
 local OverlapGroup = require("ui/widget/overlapgroup")
 local ImageWidget = require("ui/widget/imagewidget")
 local UIManager = require("ui/uimanager")
-local Screen = require("device").screen
+local Device = require("device")
+local Screen = Device.screen
 local Geom = require("ui/geometry")
 local Event = require("ui/event")
 local dbg = require("dbg")
 local Blitbuffer = require("ffi/blitbuffer")
 local _ = require("gettext")
+local ReaderKoboLight = require("apps/reader/modules/readerkobolight")
 
 local ReaderView = OverlapGroup:new{
     document = nil,
@@ -109,6 +111,13 @@ function ReaderView:addWidgets()
     self[1] = self.dogear
     self[2] = self.footer
     self[3] = self.flipping
+    if (Device:isKobo() and Device:hasFrontlight()) then
+        self.kobolight = ReaderKoboLight:new{
+            view = self,
+            ui = self.ui,
+        }
+        self[4] = self.kobolight
+    end
 end
 
 function ReaderView:resetLayout()