local BD = require("ui/bidi")
local CenterContainer = require("ui/widget/container/centercontainer")
local ConfirmBox = require("ui/widget/confirmbox")
local Device = require("device")
local Event = require("ui/event")
local InputContainer = require("ui/widget/container/inputcontainer")
local PluginLoader = require("pluginloader")
local Screensaver = require("ui/screensaver")
local UIManager = require("ui/uimanager")
local logger = require("logger")
local dbg = require("dbg")
local util  = require("util")
local Screen = Device.screen
local _ = require("gettext")
local T = require("ffi/util").template

local ReaderMenu = InputContainer:extend{
    tab_item_table = nil,
    menu_items = nil, -- table, mandatory
    registered_widgets = nil, -- array
}

function ReaderMenu:init()
    self.menu_items = {
        ["KOMenu:menu_buttons"] = {
            -- top menu
        },
        -- items in top menu
        navi = {
            icon = "appbar.navigation",
        },
        typeset = {
            icon = "appbar.typeset",
        },
        setting = {
            icon = "appbar.settings",
        },
        tools = {
            icon = "appbar.tools",
        },
        search = {
            icon = "appbar.search",
        },
        filemanager = {
            icon = "appbar.filebrowser",
            remember = false,
            callback = function()
                self:onTapCloseMenu()
                local file = self.ui.document.file
                self.ui:onClose()
                self.ui:showFileManager(file)
            end,
        },
        main = {
            icon = "appbar.menu",
        }
    }

    self.registered_widgets = {}

    self:registerKeyEvents()

    if G_reader_settings:has("activate_menu") then
        self.activation_menu = G_reader_settings:readSetting("activate_menu")
    else
        self.activation_menu = "swipe_tap"
    end

    -- delegate gesture listener to readerui, NOP our own
    self.ges_events = nil
end

function ReaderMenu:onGesture() end

function ReaderMenu:registerKeyEvents()
    if Device:hasKeys() then
        if Device:isTouchDevice() then
            self.key_events.PressMenu = { { "Menu" } }
            if Device:hasFewKeys() then
                self.key_events.PressMenu = { { { "Menu", "Right" } } }
            end
        else
            -- Map Menu key to top menu only, because the bottom menu is only designed for touch devices.
            self.key_events.KeyPressShowMenu = { { "Menu" } }
            if Device:hasFewKeys() then
                self.key_events.KeyPressShowMenu = { { { "Menu", "Right" } } }
            end
        end
    end
end

ReaderMenu.onPhysicalKeyboardConnected = ReaderMenu.registerKeyEvents

function ReaderMenu:getPreviousFile()
    return require("readhistory"):getPreviousFile(self.ui.document.file)
end

function ReaderMenu:initGesListener()
    if not Device:isTouchDevice() then return end

    local DTAP_ZONE_MENU = G_defaults:readSetting("DTAP_ZONE_MENU")
    local DTAP_ZONE_MENU_EXT = G_defaults:readSetting("DTAP_ZONE_MENU_EXT")
    self.ui:registerTouchZones({
        {
            id = "readermenu_tap",
            ges = "tap",
            screen_zone = {
                ratio_x = DTAP_ZONE_MENU.x, ratio_y = DTAP_ZONE_MENU.y,
                ratio_w = DTAP_ZONE_MENU.w, ratio_h = DTAP_ZONE_MENU.h,
            },
            overrides = {
                "tap_forward",
                "tap_backward",
            },
            handler = function(ges) return self:onTapShowMenu(ges) end,
        },
        {
            id = "readermenu_ext_tap",
            ges = "tap",
            screen_zone = {
                ratio_x = DTAP_ZONE_MENU_EXT.x, ratio_y = DTAP_ZONE_MENU_EXT.y,
                ratio_w = DTAP_ZONE_MENU_EXT.w, ratio_h = DTAP_ZONE_MENU_EXT.h,
            },
            overrides = {
                "readermenu_tap",
            },
            handler = function(ges) return self:onTapShowMenu(ges) end,
        },
        {
            id = "readermenu_swipe",
            ges = "swipe",
            screen_zone = {
                ratio_x = DTAP_ZONE_MENU.x, ratio_y = DTAP_ZONE_MENU.y,
                ratio_w = DTAP_ZONE_MENU.w, ratio_h = DTAP_ZONE_MENU.h,
            },
            overrides = {
                "rolling_swipe",
                "paging_swipe",
            },
            handler = function(ges) return self:onSwipeShowMenu(ges) end,
        },
        {
            id = "readermenu_ext_swipe",
            ges = "swipe",
            screen_zone = {
                ratio_x = DTAP_ZONE_MENU_EXT.x, ratio_y = DTAP_ZONE_MENU_EXT.y,
                ratio_w = DTAP_ZONE_MENU_EXT.w, ratio_h = DTAP_ZONE_MENU_EXT.h,
            },
            overrides = {
                "readermenu_swipe",
            },
            handler = function(ges) return self:onSwipeShowMenu(ges) end,
        },
        {
            id = "readermenu_pan",
            ges = "pan",
            screen_zone = {
                ratio_x = DTAP_ZONE_MENU.x, ratio_y = DTAP_ZONE_MENU.y,
                ratio_w = DTAP_ZONE_MENU.w, ratio_h = DTAP_ZONE_MENU.h,
            },
            overrides = {
                "rolling_pan",
                "paging_pan",
            },
            handler = function(ges) return self:onSwipeShowMenu(ges) end,
        },
        {
            id = "readermenu_ext_pan",
            ges = "pan",
            screen_zone = {
                ratio_x = DTAP_ZONE_MENU_EXT.x, ratio_y = DTAP_ZONE_MENU_EXT.y,
                ratio_w = DTAP_ZONE_MENU_EXT.w, ratio_h = DTAP_ZONE_MENU_EXT.h,
            },
            overrides = {
                "readermenu_pan",
            },
            handler = function(ges) return self:onSwipeShowMenu(ges) end,
        },
    })
end

ReaderMenu.onReaderReady = ReaderMenu.initGesListener

function ReaderMenu:setUpdateItemTable()
    for _, widget in pairs(self.registered_widgets) do
        local ok, err = pcall(widget.addToMainMenu, widget, self.menu_items)
        if not ok then
            logger.err("failed to register widget", widget.name, err)
        end
    end

    -- typeset tab
    self.menu_items.document_settings = {
        text = _("Document settings"),
        sub_item_table = {
            {
                text = _("Reset document settings to default"),
                keep_menu_open = true,
                callback = function()
                    UIManager:show(ConfirmBox:new{
                        text = _("Reset current document settings to their default values?\n\nReading position, highlights and bookmarks will be kept.\nThe document will be reloaded."),
                        ok_text = _("Reset"),
                        ok_callback = function()
                            local current_file = self.ui.document.file
                            self:onTapCloseMenu()
                            self.ui:onClose()
                            require("apps/filemanager/filemanagerutil").resetDocumentSettings(current_file)
                            require("apps/reader/readerui"):showReader(current_file)
                        end,
                    })
                end,
            },
            {
                text = _("Save document settings as default"),
                keep_menu_open = true,
                separator = true,
                callback = function()
                    UIManager:show(ConfirmBox:new{
                        text = _("Save current document settings as default values?"),
                        ok_text = _("Save"),
                        ok_callback = function()
                            self:onTapCloseMenu()
                            self:saveDocumentSettingsAsDefault()
                            UIManager:show(require("ui/widget/notification"):new{
                                text = _("Default settings updated"),
                            })
                        end,
                    })
                end,
            },
        },
    }

    if not Device:isTouchDevice() then
        -- This menu entry is a duplicate of the one found in page_turns for touch devices
        -- but we need to add it here for non-touch devices.
        table.insert(self.menu_items.document_settings.sub_item_table, {
            text_func = function()
                local text = _("Invert document-related dialogs")
                if G_reader_settings:isTrue("invert_ui_layout") then
                    text = text .. "   ★"
                end
                return text
            end,
            checked_func = function()
                return self.view:shouldInvertBiDiLayoutMirroring()
            end,
            callback = function()
                UIManager:broadcastEvent(Event:new("ToggleUILayoutMiroring"))
            end,
            hold_callback = function(touchmenu_instance)
                local invert_ui_layout = G_reader_settings:isTrue("invert_ui_layout")
                local MultiConfirmBox = require("ui/widget/multiconfirmbox")
                UIManager:show(MultiConfirmBox:new{
                    text = invert_ui_layout and _("The default (★) for newly opened books is to Invert document-related dialogs.\n\nWould you like to change it?")
                    or _("The default (★) for newly opened books is not to Invert document-related dialogs.\n\nWould you like to change it?"),
                    choice1_text_func = function()
                        return invert_ui_layout and _("Don't invert") or _("Don't invert") .." (★)"
                    end,
                    choice1_callback = function()
                        G_reader_settings:makeFalse("invert_ui_layout")
                        if touchmenu_instance then touchmenu_instance:updateItems() end
                    end,
                    choice2_text_func = function()
                        return invert_ui_layout and _("Invert") .." (★)" or _("Invert")
                    end,
                    choice2_callback = function()
                        G_reader_settings:makeTrue("invert_ui_layout")
                        if touchmenu_instance then touchmenu_instance:updateItems() end
                    end,
                })
            end,
            help_text = _([[
When enabled the UI direction for the Table of Contents, Book Map, and Page Browser dialogs will mirror the default UI direction.
Useful when used alongside 'Invert page turn taps and swipes'.]]),
        })
    end

    self.menu_items.page_overlap = dofile("frontend/ui/elements/page_overlap.lua")

    -- settings tab
    -- insert common settings
    for id, common_setting in pairs(dofile("frontend/ui/elements/common_settings_menu_table.lua")) do
        self.menu_items[id] = common_setting
    end

    if Device:isTouchDevice() then
        -- Settings > Taps & Gestures; mostly concerns touch related page turn stuff, and only applies to Reader
        self.menu_items.page_turns = dofile("frontend/ui/elements/page_turns.lua")
    end
    -- Settings > Navigation; while also related to page turns, this mostly concerns physical keys, and applies *everywhere*
    if Device:hasKeys() then
        self.menu_items.physical_buttons_setup = dofile("frontend/ui/elements/physical_buttons.lua")
    end
    -- insert DjVu render mode submenu just before the last entry (show advanced)
    -- this is a bit of a hack
    if self.ui.document.is_djvu then
        self.menu_items.djvu_render_mode = self.view:getRenderModeMenuTable()
    end

    if Device:supportsScreensaver() then
        local screensaver_sub_item_table = dofile("frontend/ui/elements/screensaver_menu.lua")
        table.insert(screensaver_sub_item_table, {
            text = _("Do not show this book cover on sleep screen"),
            enabled_func = function()
                local screensaver_type = G_reader_settings:readSetting("screensaver_type")
                return screensaver_type == "cover" or screensaver_type == "disable"
            end,
            checked_func = function()
                return self.ui.doc_settings:isTrue("exclude_screensaver")
            end,
            callback = function()
                if Screensaver.isExcluded(self.ui) then
                    self.ui.doc_settings:makeFalse("exclude_screensaver")
                else
                    self.ui.doc_settings:makeTrue("exclude_screensaver")
                end
                self.ui:saveSettings()
            end,
        })
        self.menu_items.screensaver = {
            text = _("Sleep screen"),
            sub_item_table = screensaver_sub_item_table,
        }
    end

    -- tools tab
    self.menu_items.plugin_management = {
        text = _("Plugin management"),
        sub_item_table = PluginLoader:genPluginManagerSubItem(),
    }
    self.menu_items.patch_management = dofile("frontend/ui/elements/patch_management.lua")

    -- main menu tab
    -- insert common info
    for id, common_setting in pairs(dofile("frontend/ui/elements/common_info_menu_table.lua")) do
        self.menu_items[id] = common_setting
    end
    -- insert common exit for reader
    for id, common_setting in pairs(dofile("frontend/ui/elements/common_exit_menu_table.lua")) do
        self.menu_items[id] = common_setting
    end

    self.menu_items.open_previous_document = {
        text_func = function()
            local previous_file = self:getPreviousFile()
            if not G_reader_settings:isTrue("open_last_menu_show_filename") or not previous_file then
                return _("Open previous document")
            end
            local path, file_name = util.splitFilePathName(previous_file) -- luacheck: no unused
            return T(_("Previous: %1"), BD.filename(file_name))
        end,
        enabled_func = function()
            return self:getPreviousFile() ~= nil
        end,
        callback = function()
            self.ui:onOpenLastDoc()
        end,
        hold_callback = function()
            local previous_file = self:getPreviousFile()
            UIManager:show(ConfirmBox:new{
                text = T(_("Would you like to open the previous document: %1?"), BD.filepath(previous_file)),
                ok_text = _("OK"),
                ok_callback = function()
                    self.ui:switchDocument(previous_file)
                end,
            })
        end
    }

    -- NOTE: This is cached via require for ui/plugin/insert_menu's sake...
    local order = require("ui/elements/reader_menu_order")

    local MenuSorter = require("ui/menusorter")
    self.tab_item_table = MenuSorter:mergeAndSort("reader", self.menu_items, order)
end
dbg:guard(ReaderMenu, 'setUpdateItemTable',
    function(self)
        local mock_menu_items = {}
        for _, widget in pairs(self.registered_widgets) do
            -- make sure addToMainMenu works in debug mode
            widget:addToMainMenu(mock_menu_items)
        end
    end)

function ReaderMenu:saveDocumentSettingsAsDefault()
    local prefix
    if self.ui.rolling then
        G_reader_settings:saveSetting("cre_font", self.ui.font.font_face)
        G_reader_settings:saveSetting("copt_css", self.ui.document.default_css)
        local style_tweaks = G_reader_settings:readSetting("style_tweaks")
        for tweak_id, is_enabled in pairs(self.ui.styletweak.doc_tweaks) do
            style_tweaks[tweak_id] = is_enabled or nil
        end
        prefix = "copt_"
    else
        prefix = "kopt_"
    end
    for k, v in pairs(self.ui.document.configurable) do
        G_reader_settings:saveSetting(prefix .. k, v)
    end
end

function ReaderMenu:exitOrRestart(callback, force)
    -- Only restart sets a callback, which suits us just fine for this check ;)
    if callback and not force and not Device:isStartupScriptUpToDate() then
        UIManager:show(ConfirmBox:new{
            text = _("KOReader's startup script has been updated. You'll need to completely exit KOReader to finalize the update."),
            ok_text = _("Restart anyway"),
            ok_callback = function()
                self:exitOrRestart(callback, true)
            end,
        })
        return
    end

    self:onTapCloseMenu()
    UIManager:nextTick(function()
        self.ui:onClose()
        if callback then
            callback()
        end
    end)
end

function ReaderMenu:onShowMenu(tab_index, do_not_show)
    if self.tab_item_table == nil then
        self:setUpdateItemTable()
    end

    local menu_container = CenterContainer:new{
        covers_header = true,
        ignore = "height",
        dimen = Screen:getSize(),
    }

    local main_menu
    if Device:isTouchDevice() or Device:hasDPad() then
        local TouchMenu = require("ui/widget/touchmenu")
        main_menu = TouchMenu:new{
            width = Screen:getWidth(),
            last_index = tab_index or self.last_tab_index,
            tab_item_table = self.tab_item_table,
            show_parent = menu_container,
            not_shown = do_not_show,
        }
    else
        local Menu = require("ui/widget/menu")
        main_menu = Menu:new{
            title = _("Document menu"),
            item_table = Menu.itemTableFromTouchMenu(self.tab_item_table),
            width = Screen:getWidth() - 100,
            show_parent = menu_container,
        }
    end

    main_menu.close_callback = function()
        self:onCloseReaderMenu()
    end

    main_menu.touch_menu_callback = function ()
        self.ui:handleEvent(Event:new("CloseConfigMenu"))
    end

    menu_container[1] = main_menu
    -- maintain a reference to menu_container
    self.menu_container = menu_container
    if not do_not_show then
        UIManager:show(menu_container)
    end
    return true
end

function ReaderMenu:onCloseReaderMenu()
    if not self.menu_container then return true end
    self.last_tab_index = self.menu_container[1].last_index
    self:onSaveSettings()
    UIManager:close(self.menu_container)
    self.menu_container = nil
    return true
end

function ReaderMenu:onSetDimensions(dimen)
    -- This widget doesn't support in-place layout updates, so, close & reopen
    if self.menu_container then
        self:onCloseReaderMenu()
        self:onShowMenu()
    end

    -- update gesture zones according to new screen dimen
    -- (On CRe, this will get called a second time by ReaderReady once the document is reloaded).
    self:initGesListener()
end

function ReaderMenu:_getTabIndexFromLocation(ges)
    if self.tab_item_table == nil then
        self:setUpdateItemTable()
    end
    if not ges then
        return self.last_tab_index
    -- if the start position is far right
    elseif ges.pos.x > Screen:getWidth() * (2/3) then
        return BD.mirroredUILayout() and 1 or #self.tab_item_table
    -- if the start position is far left
    elseif ges.pos.x < Screen:getWidth() * (1/3) then
        return BD.mirroredUILayout() and #self.tab_item_table or 1
    -- if center return the last index
    else
        return self.last_tab_index
    end
end

function ReaderMenu:onSwipeShowMenu(ges)
    if self.activation_menu ~= "tap" and ges.direction == "south" then
        if G_reader_settings:nilOrTrue("show_bottom_menu") then
            self.ui:handleEvent(Event:new("ShowConfigMenu"))
        end
        self:onShowMenu(self:_getTabIndexFromLocation(ges))
        self.ui:handleEvent(Event:new("HandledAsSwipe")) -- cancel any pan scroll made
        return true
    end
end

function ReaderMenu:onTapShowMenu(ges)
    if self.activation_menu ~= "swipe" then
        if G_reader_settings:nilOrTrue("show_bottom_menu") then
            self.ui:handleEvent(Event:new("ShowConfigMenu"))
        end
        self:onShowMenu(self:_getTabIndexFromLocation(ges))
        return true
    end
end

function ReaderMenu:onPressMenu()
    if G_reader_settings:nilOrTrue("show_bottom_menu") then
        self.ui:handleEvent(Event:new("ShowConfigMenu"))
    end
    self:onShowMenu()
    return true
end

function ReaderMenu:onKeyPressShowMenu(_, key_ev)
    return self:onShowMenu()
end

function ReaderMenu:onTapCloseMenu()
    self:onCloseReaderMenu()
    self.ui:handleEvent(Event:new("CloseConfigMenu"))
end

function ReaderMenu:onReadSettings(config)
    self.last_tab_index = config:readSetting("readermenu_tab_index") or 1
end

function ReaderMenu:onSaveSettings()
    self.ui.doc_settings:saveSetting("readermenu_tab_index", self.last_tab_index)
end

function ReaderMenu:onMenuSearch()
    self:onShowMenu(nil, true)
    self.menu_container[1]:onShowMenuSearch()
end

function ReaderMenu:registerToMainMenu(widget)
    table.insert(self.registered_widgets, widget)
end

function ReaderMenu:onShowCloudStorage()
    local CloudStorage = require("apps/cloudstorage/cloudstorage")
    UIManager:show(CloudStorage:new{ ui = self.ui })
    return true
end

return ReaderMenu