[chore] Device abstraction (#6280)

* generic Device:info() function which returns the model

* add Device:canSuspend() and make it true in all devices that have suspend routines and the emulator

* also enable fake poweroff/reboot on the emulator

* add Device.home_dir

* add Device:hasExitOptions() and update menus & comments

frontend/apps/filemanager/filemanager.lua

@@ -681,17 +681,7 @@ function FileManager:goHome()
     local home_dir = G_reader_settings:readSetting("home_dir")
     if not home_dir or lfs.attributes(home_dir, "mode") ~= "directory"  then
         -- Try some sane defaults, depending on platform
-        if Device:isKindle() then
-            home_dir = "/mnt/us"
-        elseif Device:isKobo() then
-            home_dir = "/mnt/onboard"
-        elseif Device:isPocketBook() then
-            home_dir = "/mnt/ext1"
-        elseif Device:isCervantes() then
-            home_dir = "/mnt/public"
-        elseif Device:isAndroid() then
-            home_dir = Device.external_storage()
-        end
+        home_dir = Device.home_dir
     end
     if home_dir then
         -- Jump to the first page if we're already home

frontend/apps/filemanager/filemanagerutil.lua

@@ -10,19 +10,7 @@ local _ = require("gettext")
 local filemanagerutil = {}
 
 function filemanagerutil.getDefaultDir()
-    if Device:isAndroid() then
-        return Device.external_storage()
-    elseif Device:isCervantes() then
-        return "/mnt/public"
-    elseif Device:isKindle() then
-        return "/mnt/us/documents"
-    elseif Device:isKobo() then
-        return "/mnt/onboard"
-    elseif Device:isRemarkable() then
-        return "/home/root"
-    else
-        return "."
-    end
+    return Device.home_dir or "."
 end
 
 function filemanagerutil.abbreviate(path)

frontend/device/android/device.lua

@@ -67,13 +67,15 @@ local Device = Generic:new{
     model = android.prop.product,
     hasKeys = yes,
     hasDPad = no,
+    hasExitOptions = no,
     hasEinkScreen = function() return android.isEink() end,
     hasColorScreen = function() return not android.isEink() end,
     hasFrontlight = yes,
     hasLightLevelFallback = yes,
     canRestart = no,
+    canSuspend = no,
     firmware_rev = android.app.activity.sdkVersion,
-    external_storage = android.getExternalStoragePath,
+    home_dir = android.getExternalStoragePath(),
     display_dpi = android.lib.AConfiguration_getDensity(android.app.config),
     isHapticFeedbackEnabled = yes,
     hasClipboard = yes,

frontend/device/cervantes/device.lua

@@ -62,6 +62,7 @@ local Cervantes = Generic:new{
     hasWifiManager = yes,
     canReboot = yes,
     canPowerOff = yes,
+    home_dir = "/mnt/public",
 
     -- do we support usb mass storage?
     canToggleMassStorage = function() return isMassStorageSupported() end,

frontend/device/generic/device.lua

@@ -21,6 +21,7 @@ local Device = {
     screen = nil,
     screen_dpi_override = nil,
     input = nil,
+    home_dir = nil,
     -- For Kobo, wait at least 15 seconds before calling suspend script. Otherwise, suspend might
     -- fail and the battery will be drained while we are in screensaver mode
     suspend_wait_timeout = 15,
@@ -29,6 +30,7 @@ local Device = {
     hasKeyboard = no,
     hasKeys = no,
     hasDPad = no,
+    hasExitOptions = yes,
     hasFewKeys = no,
     hasWifiToggle = yes,
     hasWifiManager = no,
@@ -52,6 +54,7 @@ local Device = {
     canToggleMassStorage = no,
     canUseWAL = yes, -- requires mmap'ed I/O on the target FS
     canRestart = yes,
+    canSuspend = yes,
     canReboot = no,
     canPowerOff = no,
 
@@ -279,6 +282,10 @@ function Device:onPowerEvent(ev)
     end
 end
 
+function Device:info()
+    return self.model
+end
+
 -- Hardware specific method to handle usb plug in event
 function Device:usbPlugIn() end
 

frontend/device/kindle/device.lua

@@ -96,6 +96,7 @@ local Kindle = Generic:new{
     canHWInvert = yes,
     -- NOTE: Newer devices will turn the frontlight off at 0
     canTurnFrontlightOff = yes,
+    home_dir = "/mnt/us/documents",
 }
 
 function Kindle:initNetworkManager(NetworkMgr)

frontend/device/kobo/device.lua

@@ -47,6 +47,7 @@ local Kobo = Generic:new{
     hasNaturalLightMixer = no,
     -- HW inversion is generally safe on Kobo, except on a few boards/kernels
     canHWInvert = yes,
+    home_dir = "/mnt/onboard",
 }
 
 --- @todo hasKeys for some devices?

frontend/device/pocketbook/device.lua

@@ -63,7 +63,9 @@ local PocketBook = Generic:new{
     isTouchDevice = yes,
     hasKeys = yes,
     hasFrontlight = yes,
+    canSuspend = no,
     emu_events_dev = "/dev/shm/emu_events",
+    home_dir = "/mnt/ext1",
 }
 
 -- Make sure the C BB cannot be used on devices with a 24bpp fb

frontend/device/remarkable/device.lua

@@ -14,6 +14,7 @@ local Remarkable = Generic:new{
     isTouchDevice = yes,
     hasFrontlight = no,
     display_dpi = 226,
+    home_dir = "/mnt/root",
 }
 
 local EV_ABS = 3

frontend/device/sdl/device.lua

@@ -80,6 +80,7 @@ local Device = Generic:new{
     needsScreenRefreshAfterResume = no,
     hasColorScreen = yes,
     hasEinkScreen = no,
+    canSuspend = no,
     canOpenLink = getLinkOpener,
     openLink = function(self, link)
         local enabled, tool = getLinkOpener()
@@ -114,6 +115,7 @@ local AppImage = Device:new{
     hasMultitouch = no,
     hasOTAUpdates = yes,
     isDesktop = yes,
+    home_dir = os.getenv("HOME"),
 }
 
 local Emulator = Device:new{
@@ -123,11 +125,15 @@ local Emulator = Device:new{
     hasFrontlight = yes,
     hasWifiToggle = yes,
     hasWifiManager = yes,
+    canPowerOff = yes,
+    canReboot = yes,
+    canSuspend = yes,
 }
 
 local Linux = Device:new{
     model = "Linux",
     isDesktop = yes,
+    home_dir = os.getenv("HOME"),
 }
 
 local UbuntuTouch = Device:new{

frontend/ui/elements/common_info_menu_table.lua

@@ -55,19 +55,14 @@ common_info.report_bug = {
     text = _("Report a bug"),
     keep_menu_open = true,
     callback = function()
-        local device = Device.model
-        if Device:isAndroid() then
-            device = Device:info()
-        end
-
         UIManager:show(InfoMessage:new{
             text = T(_("Please report bugs to \nhttps://github.com/koreader/koreader/issues\n\nVersion:\n%1\n\nDetected device:\n%2"),
-                version, device),
+                version, Device:info()),
         })
     end
 }
 
-if Device:isCervantes() or Device:isKindle() or Device:isKobo() then
+if Device:canSuspend() then
     common_info.sleep = {
         text = _("Sleep"),
         callback = function()

frontend/ui/elements/filemanager_menu_order.lua

@@ -154,19 +154,18 @@ local order = {
     },
     plus_menu = {},
     exit_menu = {
-        "restart_koreader",
+        "restart_koreader", -- if Device:canRestart()
         "----------------------------",
-        "sleep", -- if Device:isKindle() or Device:isKobo()
-        "poweroff", -- if Device:isKobo()
-        "reboot",   -- if Device:isKobo()
+        "sleep", -- if Device:canSuspend()
+        "poweroff", -- if Device:canPowerOff()
+        "reboot", -- if Device:canReboot()
         "----------------------------",
-        "start_bq",
+        "start_bq", -- if Device:isCervantes()
         "exit",
     }
 }
 
-if Device:isAndroid() then
+if not Device:hasExitOptions() then
     order.exit_menu = nil
 end
-
 return order

frontend/ui/elements/reader_menu_order.lua

@@ -178,18 +178,18 @@ local order = {
         "about",
     },
     exit_menu = {
-        "restart_koreader",
+        "restart_koreader", -- if Device:canRestart()
         "----------------------------",
-        "sleep", -- if Device:isKindle() or Device:isKobo()
-        "poweroff", -- if Device:isKobo()
-        "reboot",   -- if Device:isKobo()
+        "sleep", -- if Device:canSuspend()
+        "poweroff", -- if Device:canPowerOff()
+        "reboot", -- if Device:canReboot()
         "----------------------------",
-        "start_bq",
+        "start_bq", -- if Device:isCervantes()
         "exit",
     }
 }
 
-if Device:isAndroid() then
+if not Device:hasExitOptions() then
     order.exit_menu = nil
 end