[Desktop] Open writable font dir, toggle system+user/user fonts, fix openLink on mac (#5220)

Fixes #5093

frontend/apps/reader/modules/readerfont.lua

@@ -49,6 +49,9 @@ function ReaderFont:init()
     end
     -- build face_table for menu
     self.face_table = {}
+    if Device:isDesktop() then
+        table.insert(self.face_table, require("ui/elements/font_settings"):getMenuTable())
+    end
     local face_list = cre.getFontFaces()
     for k,v in ipairs(face_list) do
         table.insert(self.face_table, {

frontend/device/generic/device.lua

@@ -40,6 +40,9 @@ local Device = {
     canToggleGSensor = no,
     canToggleMassStorage = no,
     canUseWAL = yes, -- requires mmap'ed I/O on the target FS
+    canRestart = yes,
+    canReboot = no,
+    canPowerOff = no,
 
     -- use these only as a last resort. We should abstract the functionality
     -- and have device dependent implementations in the corresponting
@@ -53,9 +56,7 @@ local Device = {
     isSonyPRSTUX = no,
     isSDL = no,
     isEmulator = no,
-    canRestart = yes,
+    isDesktop = no,
-    canReboot = no,
-    canPowerOff = no,
 
     -- some devices have part of their screen covered by the bezel
     viewport = nil,

frontend/device/sdl/device.lua

@@ -6,6 +6,42 @@ local logger = require("logger")
 local function yes() return true end
 local function no() return false end
 
+-- xdg-open is used on most linux systems
+local function hasXdgOpen()
+    local std_out = io.popen("xdg-open --version 2>/dev/null")
+    local version = nil
+    if std_out ~= nil then
+        version = std_out:read()
+        std_out:close()
+    end
+    return version ~= nil
+end
+
+-- open is the macOS counterpart
+local function hasMacOpen()
+    local std_out = io.popen("open")
+    local all = nil
+    if std_out ~= nil then
+        all = std_out:read()
+        std_out:close()
+    end
+    return all ~= nil
+end
+
+-- get the name of the binary used to open links
+local function getLinkOpener()
+    local enabled = false
+    local tool = nil
+    if jit.os == "Linux" and hasXdgOpen() then
+        enabled = true
+        tool = "xdg-open"
+    elseif jit.os == "OSX" and hasMacOpen() then
+        enabled = true
+        tool = "open"
+    end
+    return enabled, tool
+end
+
 local Device = Generic:new{
     model = "SDL",
     isSDL = yes,
@@ -17,10 +53,11 @@ local Device = Generic:new{
     needsScreenRefreshAfterResume = no,
     hasColorScreen = yes,
     hasEinkScreen = no,
-    canOpenLink = yes,
+    canOpenLink = getLinkOpener,
     openLink = function(self, link)
-        if not link or type(link) ~= "string" then return end
+        local enabled, tool = getLinkOpener()
-        return os.execute("xdg-open '"..link.."'") == 0
+        if not enabled or not tool or not link or type(link) ~= "string" then return end
+        return os.execute(tool.." '"..link.."'") == 0
     end,
 }
 
@@ -28,6 +65,7 @@ local AppImage = Device:new{
     model = "AppImage",
     hasMultitouch = no,
     hasOTAUpdates = yes,
+    isDesktop = yes,
 }
 
 local Emulator = Device:new{
@@ -37,10 +75,12 @@ local Emulator = Device:new{
     hasFrontlight = yes,
     hasWifiToggle = yes,
     hasWifiManager = yes,
+    isDesktop = yes,
 }
 
 local Linux = Device:new{
     model = "Linux",
+    isDesktop = yes,
 }
 
 local UbuntuTouch = Device:new{

frontend/document/canvascontext.lua

@@ -37,6 +37,7 @@ The following key is required for a device object:
 function CanvasContext:init(device)
     self.screen = device.screen
     self.isAndroid = device.isAndroid
+    self.isDesktop = device.isDesktop
     self.isKindle = device.isKindle
     self.should_restrict_JIT = device.should_restrict_JIT
     self:setColorRenderingEnabled(device.screen.isColorEnabled())

frontend/fontlist.lua

@@ -65,6 +65,8 @@ end
 local function getExternalFontDir()
     if CanvasContext.isAndroid() then
         return ANDROID_FONT_DIR
+    elseif CanvasContext.isDesktop() then
+        return require("frontend/ui/elements/font_settings"):getPath()
     else
         return os.getenv("EXT_FONT_DIR")
     end

frontend/ui/elements/font_settings.lua

@@ -0,0 +1,81 @@
+local Device = require("device")
+local logger = require("logger")
+local util = require("util")
+local _ = require("gettext")
+
+--[[ Font settings for desktop linux and mac ]]--
+
+local function getUserDir()
+    return os.getenv("HOME").."/.local/share/fonts"
+end
+
+-- System fonts are common in linux
+local function getSystemDir()
+    local path = "/usr/share/fonts"
+    if util.pathExists(path) then
+        return path
+    else
+        -- mac doesn't use ttf fonts
+        return nil
+    end
+end
+
+local function usesSystemFonts()
+    return G_reader_settings:isTrue("system_fonts")
+end
+
+local function openFontDir()
+    local user_dir = getUserDir()
+    local openable = util.pathExists(user_dir)
+    if not openable then
+        logger.info("Font path not found, making one in ", user_dir)
+        openable = util.makePath(user_dir)
+    end
+    if not openable then
+        logger.warn("Unable to create the folder ", user_dir)
+        return
+    end
+    if Device:canOpenLink() then
+        Device:openLink(user_dir)
+    end
+end
+
+local FontSettings = {}
+
+function FontSettings:getPath()
+    if usesSystemFonts() then
+        local system_path = getSystemDir()
+        if system_path ~= nil then
+            return getUserDir()..";"..system_path
+        end
+    end
+    return getUserDir()
+end
+
+function FontSettings:getMenuTable()
+    return {
+        text = _("Font settings"),
+        separator = true,
+        sub_item_table = {
+            {
+                text = _("Enable system fonts"),
+                checked_func = usesSystemFonts,
+                callback = function()
+                    G_reader_settings:saveSetting("system_fonts", not usesSystemFonts())
+                    local UIManager = require("ui/uimanager")
+                    local InfoMessage = require("ui/widget/infomessage")
+                    UIManager:show(InfoMessage:new{
+                        text = _("This will take effect on next restart.")
+                    })
+                end,
+            },
+            {
+                text = _("Open fonts folder"),
+                keep_menu_open = true,
+                callback = openFontDir,
+            },
+        }
+    }
+end
+
+return FontSettings

platform/appimage/AppRun

@@ -10,9 +10,6 @@ cd "${KOREADER_DIR}" || exit
 # export load library path
 export LD_LIBRARY_PATH=${KOREADER_DIR}/libs:$LD_LIBRARY_PATH
 
-# export external font directory
-export EXT_FONT_DIR="${HOME}/.fonts"
-
 RETURN_VALUE=85
 
 if [ $# -eq 0 ]; then

platform/debian/koreader.sh

@@ -23,10 +23,6 @@ cd "${KOREADER_DIR}" || exit
 # export load library path
 export LD_LIBRARY_PATH=${KOREADER_DIR}/libs:$LD_LIBRARY_PATH
 
-# export external font directory
-export EXT_FONT_DIR="${HOME}/.config/koreader/fonts"
-[ ! -d "${EXT_FONT_DIR}" ] && mkdir -pv "${EXT_FONT_DIR}"
-
 RETURN_VALUE=85
 while [ $RETURN_VALUE -eq 85 ]; do
     ./reader.lua "${ARGS}"