--[[--
This widget displays a keyboard layout dialog.
]]

local Blitbuffer = require("ffi/blitbuffer")
local ButtonTable = require("ui/widget/buttontable")
local CenterContainer = require("ui/widget/container/centercontainer")
local FFIUtil = require("ffi/util")
local FocusManager = require("ui/widget/focusmanager")
local FrameContainer = require("ui/widget/container/framecontainer")
local Geom = require("ui/geometry")
local Language = require("ui/language")
local MovableContainer = require("ui/widget/container/movablecontainer")
local RadioButtonTable = require("ui/widget/radiobuttontable")
local ScrollableContainer = require("ui/widget/container/scrollablecontainer")
local Size = require("ui/size")
local TitleBar = require("ui/widget/titlebar")
local UIManager = require("ui/uimanager")
local VerticalGroup = require("ui/widget/verticalgroup")
local VerticalSpan = require("ui/widget/verticalspan")
local util = require("util")
local _ = require("gettext")
local Device = require("device")
local Screen = Device.screen

local KeyboardLayoutDialog = FocusManager:extend{
    is_always_active = true,
    modal = true,
    stop_events_propagation = true,
    keyboard_state = nil,
    width = nil,
}

function KeyboardLayoutDialog:init()
    self.layout = {}
    self.width = self.width or math.floor(math.min(Screen:getWidth(), Screen:getHeight()) * 0.8)
    self.title_bar = TitleBar:new{
        width = self.width,
        with_bottom_line = true,
        title = _("Keyboard layout"),
        bottom_v_padding = 0,
        show_parent = self,
    }

    local buttons = {}
    local radio_buttons = {}

    local keyboard_layouts = G_reader_settings:readSetting("keyboard_layouts", {})
    local default_layout = G_reader_settings:readSetting("keyboard_layout_default")
    self.keyboard_state.force_current_layout = true
    local current_layout = self.parent.keyboard:getKeyboardLayout()
    self.keyboard_state.force_current_layout = false
    for k, _ in FFIUtil.orderedPairs(self.parent.keyboard.lang_to_keyboard_layout) do
        local text = Language:getLanguageName(k) .. "  (" .. string.sub(k, 1, 2) .. ")"
        if util.arrayContains(keyboard_layouts, k) then
            text = text .. "  ✓"
        end
        if k == default_layout then
            text = text .. "  ★"
        end
        table.insert(radio_buttons, {
            {
                text = text,
                checked = k == current_layout,
                provider = k,
            },
        })
    end

    table.insert(buttons, {
        {
            text = _("Cancel"),
            id = "close",
            callback = function()
                UIManager:close(self.parent.keyboard_layout_dialog)
            end,
        },
        {
            text = _("Switch to layout"),
            is_enter_default = true,
            callback = function()
                local provider = self.parent.keyboard_layout_dialog.radio_button_table.checked_button.provider
                self.parent.keyboard:setKeyboardLayout(provider)
                UIManager:close(self.parent.keyboard_layout_dialog)
            end,
        },
    })

    -- (RadioButtonTable's width and padding setup is a bit fishy: we get
    -- this to look ok by using a CenterContainer to ensure some padding)
    local scroll_container_inner_width = self.width - ScrollableContainer:getScrollbarWidth()
    self.radio_button_table = RadioButtonTable:new{
        radio_buttons = radio_buttons,
        width = scroll_container_inner_width - 2*Size.padding.large,
        focused = true,
        parent = self,
        show_parent = self,
    }
    self:mergeLayoutInVertical(self.radio_button_table)

    -- Buttons Table
    self.button_table = ButtonTable:new{
        width = self.width - 2*Size.padding.default,
        buttons = buttons,
        zero_sep = true,
        show_parent = self,
    }
    self:mergeLayoutInVertical(self.button_table)

    local max_radio_button_container_height = math.floor(Screen:getHeight()*0.9
                    - self.title_bar:getHeight()
                    - Size.span.vertical_large*4 - self.button_table:getSize().h)
    local radio_button_container_height = math.min(self.radio_button_table:getSize().h, max_radio_button_container_height)

    -- Our scrollable container needs to be known as widget.cropping_widget in
    -- the widget that is passed to UIManager:show() for UIManager to ensure
    -- proper interception of inner widget self repainting/invert (mostly used
    -- when flashing for UI feedback that we want to limit to the cropped area).
    self.cropping_widget = ScrollableContainer:new{
        dimen = Geom:new{
            w = self.width,
            h = radio_button_container_height,
        },
        show_parent = self,
        CenterContainer:new{
            dimen = Geom:new{
                w = scroll_container_inner_width,
                h = self.radio_button_table:getSize().h,
            },
            self.radio_button_table,
        },
    }
    self.dialog_frame = FrameContainer:new{
        radius = Size.radius.window,
        bordersize = Size.border.window,
        padding = 0,
        margin = 0,
        background = Blitbuffer.COLOR_WHITE,
        VerticalGroup:new{
            align = "center",
            self.title_bar,
            VerticalSpan:new{
                width = Size.span.vertical_large*2,
            },
            self.cropping_widget, -- our ScrollableContainer
            VerticalSpan:new{
                width = Size.span.vertical_large*2,
            },
            -- buttons
            CenterContainer:new{
                dimen = Geom:new{
                    w = self.width,
                    h = self.button_table:getSize().h,
                },
                self.button_table,
            }
        }
    }

    self.movable = MovableContainer:new{
        self.dialog_frame,
    }
    self[1] = CenterContainer:new{
        dimen = Geom:new{
            w = Screen:getWidth(),
            h = Screen:getHeight(),
        },
        self.movable,
    }
    if Device:hasKeys() then
        self.key_events.CloseDialog = { { Device.input.group.Back } }
    end
end

function KeyboardLayoutDialog:onShow()
    UIManager:setDirty(self, function()
        return "ui", self.dialog_frame.dimen
    end)
end

function KeyboardLayoutDialog:onCloseWidget()
    UIManager:setDirty(nil, function()
        return "ui", self[1][1].dimen
    end)
end

function KeyboardLayoutDialog:onCloseDialog()
    local close_button = self.button_table:getButtonById("close")
    if close_button and close_button.enabled then
        close_button.callback()
        return true
    end
    return false
end

return KeyboardLayoutDialog