----------------------------------------------------------------------------
-- @author koniu <gkusnierz@gmail.com>
-- @copyright 2008 koniu
-- @release @AWESOME_VERSION@
----------------------------------------------------------------------------

-- Package environment
local pairs = pairs
local table = table
local wibox = wibox
local image = image
local hooks = require("awful.hooks")
local string = string
local widget = widget
local button = button
local capi = { screen = screen }
local bt = require("beautiful")
local beautiful = bt.get()

--- Notification library
module("naughty")

--- Naughty configuration - a table containing common/default popup settings.
-- You can override some of these for individual popups using args to notify().
-- @name config
-- @field timeout Number of seconds after which popups disappear.
--   Set to 0 for no timeout. Default: 5
-- @field screen Screen on which the popups will appear number. Default: 1
-- @field position Corner of the workarea the popups will appear.
--   Valid values: 'top_right', 'top_left', 'bottom_right', 'bottom_left'.
--   Default: 'top_right'
-- @field padding Space between popups and edge of the workarea. Default: 4
-- @field height Height of a single line of text. Default: 16
-- @field width Width of a popup. Default: 300
-- @field spacing Spacing between popups. Default: 1
-- @field ontop Boolean forcing popups to display on top. Default: true
-- @field margin Space between popup edge and content. Default: 10
-- @field font Popup font. Default: beautiful.font or "Verdana 8"
-- @field icon Popup icon. Default: nil
-- @field icon_size Size of the icon in pixels. Default: 16
-- @field fg Foreground color. Default: beautiful.fg_focus or '#ffffff'
-- @field bg Background color. Default: beautiful.bg_focus or '#535d6c'
-- @field border_color Border color.
--   Default:  beautiful.border_focus or '#535d6c'
-- @field border_width Border width. Default: 1
-- @field hover_timeout Delay in seconds after which hovered popup disappears.
--   Default: nil
-- @class table

config = {}
config.timeout = 5
config.screen = 1
config.position = "top_right"
config.padding = 4
config.height = 16
config.width = 300
config.spacing = 1
config.ontop = true
config.margin = 10
config.font = beautiful.font or "Verdana 8"
config.icon = nil
config.icon_size = 16
config.fg = beautiful.fg_focus or '#ffffff'
config.bg = beautiful.bg_focus or '#535d6c'
config.border_color = beautiful.border_focus or '#535d6c'
config.border_width = 1
config.hover_timeout = nil

--- Index of notifications. See config table for valid 'position' values.
-- Each element is a table consisting of:
-- @field box Wibox object containing the popup
-- @field height Popup height
-- @field die Function to be executed on timeout
-- @name notifications[position]
-- @class table

notifications = {
    top_left = {},
    top_right = {},
    bottom_left = {},
    bottom_right = {},
}

--- Evaluate desired position of the notification by index - internal
-- @param idx Index of the notification
-- @param position top_right | top_left | bottom_right | bottom_left
-- @param height Popup height
-- @return Absolute position in {x, y} dictionary

local function get_offset(idx, position, height)
    local ws = capi.screen[config.screen].workarea
    local v = {}

    -- calculate x
    if position:match("left") then
        v.x = ws.x + config.padding
    else
        v.x = ws.x + ws.width - (config.width + config.border_width*2 + config.padding)
    end

    -- calculate existing popups' height
    local existing = 0
    for i = 1, idx-1, 1 do
         existing = existing + notifications[position][i].height + config.spacing + config.border_width*2
    end

    -- calculate y
    if position:match("top") then
        v.y = ws.y + config.padding + existing
    else
        v.y = ws.y + ws.height - (config.padding + config.border_width + height + existing)
    end

    -- if positioned outside workarea, destroy oldest popup and recalculate
    if v.y + height > ws.y + ws.height or v.y < ws.y then
        idx = idx - 1
        destroy(notifications[position][1])
        v = get_offset(idx, position, height)
    end

    return v
end

--- Re-arrange notifications according to their position and index - internal
-- @return None
local function arrange()
    for p,pos in pairs(notifications) do
        for i,notification in pairs(notifications[p]) do
            local offset = get_offset(i, p, notification.height)
            notification.box:geometry({ x = offset.x, y = offset.y, width = config.width, height = notification.height })
            notification.idx = i
        end
    end
end

--- Destroy notification by index
-- @param idx Index of the notification
-- @param position One of 4 keys in notification dictionary: top_right, top_left, bottom_right, bottom_left
-- @return True if the popup was successfully destroyed, nil otherwise
function destroy(notification)
    if notification then
        notification.box.screen = nil
        hooks.timer.unregister(notification.die)
        table.remove(notifications[notification.position], notification.idx)
        arrange()
        return true
    end
end

--- Create notification. args is a dictionary of optional arguments. For more information and defaults see respective fields in config table.
-- @param text Text of the notification
-- @param timeout Time in seconds after which popup expires
-- @param title Title of the notification
-- @param position Corner of the workarea the popups will appear
-- @param icon Path to icon
-- @param icon_size Desired icon size in px
-- @param fg Foreground color
-- @param bg Background color
-- @param screen Target screen for the notification
-- @param ontop Target screen for the notification
-- @param run Function to run on left click
-- @usage naughty.notify({ title = 'Achtung!', text = 'You\'re idling', timeout = 0 })
function notify(args)
    -- gather variables together
    local timeout = args.timeout or config.timeout
    local icon = args.icon or config.icon
    local icon_size = args.icon_size or config.icon_size
    local text = args.text or ""
    local screen = args.screen or config.screen
    local ontop = args.ontop or config.ontop

    local notification = {}
    notification.position = args.position or config.position
    notification.idx = #notifications[notification.position] + 1

    local title = ""
    if args.title then title = args.title .. "\n"  end

    -- hook destroy
    local die = function () destroy(notification) end
    hooks.timer.register(timeout, die)
    notification.die = die

    local run = args.run or die

    local hover_destroy = function ()
        if config.hover_timeout == 0 then die()
          else hooks.timer.register(config.hover_timeout, die) end
    end

    -- create textbox
    local textbox = widget({ type = "textbox", name = "text", align = "flex" })
    textbox:buttons({ button({ }, 1, run),
                      button({ }, 3, die) })
    textbox.text = string.format('<margin right="'..config.margin..'" left="'..config.margin..'"/><span font_desc="%s"><b>%s</b>%s</span>',
                                  config.font, title, text)
    if config.hover_timeout then textbox.mouse_enter = hover_destroy end

    -- create iconbox
    local iconbox = nil
    if icon then
        iconbox = widget({ type = "imagebox", name = "icon", align = "left" })
        iconbox:buttons({ button({ }, 1, run),
                          button({ }, 3, die) })
        local img = image(icon)
        if icon_size then
            img = img:crop_and_scale(0,0,img.height,img.width,icon_size,icon_size)
            iconbox.resize = false
        end
        iconbox.image = img
        if config.hover_timeout then iconbox.mouse_enter = hover_destroy end
    end

    -- create container wibox
    notification.box = wibox({ name = "not" .. notification.idx,
                               position = "floating",
                               fg = args.fg or config.fg,
                               bg = args.bg or config.bg,
                               border_color = config.border_color,
                               border_width = config.border_width })

    -- position the wibox
    local lines = 1; for i in string.gmatch(title..text, "\n") do lines = lines + 1 end
    if iconbox and iconbox.image.height > lines * config.height then
        notification.height = iconbox.image.height
    else
        notification.height = lines * config.height end
    local offset = get_offset(notification.idx, notification.position, notification.height)
    notification.box:geometry({ width = config.width,
                                height = notification.height,
                                x = offset.x,
                                y = offset.y })
    notification.box.ontop = ontop
    notification.box.screen = screen

    -- populate widgets
    notification.box.widgets = { iconbox, textbox }

    -- insert the notification to the table
    table.insert(notifications[notification.position],notification)
end

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