---------------------------------------------------------------------------
-- @author Julien Danjou <julien@danjou.info>
-- @copyright 2008 Julien Danjou
---------------------------------------------------------------------------

-- Grab environment we need
local type = type
local string = string
local assert = assert
local loadstring = loadstring
local ipairs = ipairs
local pairs = pairs
local os = os
local io = io
local math = math
local setmetatable = setmetatable
local table = table
local otable = otable
local capi =
{
    awesome = awesome,
    screen = screen,
    client = client,
    mouse = mouse,
    titlebar = titlebar,
    widget = widget,
    hooks = hooks,
    keygrabber = keygrabber
}

--- awful: AWesome Functions very UsefuL
module("awful")

-- Local variable handling theme
local theme = {}

-- Various public structures
beautiful = {}
hooks = {}
hooks.user =  {}
prompt = {}
prompt.history = {}
prompt.history.data = {}
completion = {}
screen = {}
layout = {}
client = {}
client.data = {}
client.data.maximize = otable()
client.focus = {}
client.focus.history = {}
client.focus.history.data = {}
tag = {}
tag.history = {}
tag.history.data = {}
tag.history.data.past = {}
tag.history.data.current = {}
titlebar = {}
titlebar.data = otable()
widget = {}
widget.taglist = {}
widget.taglist.label = {}
widget.tasklist = {}
widget.tasklist.label = {}
client.urgent = {}
client.urgent.stack = {}
client.urgent.stack.data = {}

--- Make i cycle.
-- @param t A length.
-- @param i An absolute index to fit into #t.
-- @return The object at new index.
local function cycle(t, i)
    while i > t do i = i - t end
    while i < 1 do i = i + t end
    return i
end

--- Get the first client that got the urgent hint.
-- @return The first urgent client.
function client.urgent.get()
    if #client.urgent.stack.data > 0 then
        return client.urgent.stack.data[1]
    else
        -- fallback behaviour: iterate through clients and get the first urgent
        local clients = capi.client.get()
        for k, cl in pairs(clients) do
            if cl.urgent then
                return cl
            end
        end
    end
end

--- Jump to the client that received the urgent hint first.
function client.urgent.jumpto()
    local c = client.urgent.get()
    if c then
        local s = capi.client.focus and capi.client.focus.screen or capi.mouse.screen
        -- focus the screen
        if s ~= c.screen then
            capi.mouse.screen = c.screen
        end
        -- focus the tag
        tag.viewonly(c:tags()[1])
        -- focus the client
        capi.client.focus = c
        c:raise()
    end
end

--- Adds client to urgent stack.
-- @param The client object.
function client.urgent.stack.add(c)
    table.insert(client.urgent.stack.data, c)
end

--- Remove client from urgent stack.
-- @param The client object.
function client.urgent.stack.delete(c)
    for k, cl in ipairs(client.urgent.stack.data) do
        if c == cl then
            table.remove(client.urgent.stack.data, k)
            break
        end
    end
end

--- Remove a client from the focus history
-- @param c The client that must be removed.
function client.focus.history.delete(c)
    for k, v in ipairs(client.focus.history.data) do
        if v == c then
            table.remove(client.focus.history.data, k)
            break
        end
    end
end

--- Update client focus history.
-- @param c The client that has been focused.
function client.focus.history.add(c)
    -- Remove the client if its in stack
    client.focus.history.delete(c)
    -- Record the client has latest focused
    table.insert(client.focus.history.data, 1, c)
end

--- Get the latest focused client for a screen in history.
-- @param screen The screen number to look for.
-- @param idx The index: 0 will return first candidate,
-- 1 will return second, etc.
-- @return A client.
function client.focus.history.get(screen, idx)
    -- When this counter is equal to idx, we return the client
    local counter = 0
    local vc = capi.client.visible_get(screen)
    for k, c in ipairs(client.focus.history.data) do
        if c.screen == screen then
            for j, vcc in ipairs(vc) do
                if vcc == c then
                    if counter == idx then
                        return c
                    end
                    -- We found one, increment the counter only.
                    counter = counter + 1
                    break
                end
            end
        end
    end
    -- Argh nobody found in history, give the first one visible if there is one
    if counter == 0 then
        return vc[1]
    end
end

--- Focus the previous client in history.
function client.focus.history.previous()
    local sel = capi.client.focus
    local s
    if sel then
        s = sel.screen
    else
        s = capi.mouse.screen
    end
    local c = client.focus.history.get(s, 1)
    if c then capi.client.focus = c end
end

--- Get a client by its relative index to the focused window.
-- @usage Set i to 1 to get next, -1 to get previous.
-- @param i The index.
-- @param c Optional client.
-- @return A client, or nil if no client is available.
function client.next(i, c)
    -- Get currently focused client
    local sel = c or capi.client.focus
    if sel then
        -- Get all visible clients
        local cls = capi.client.visible_get(sel.screen)
        -- Loop upon each client
        for idx, c in ipairs(cls) do
            if c == sel then
                -- Cycle
                return cls[cycle(#cls, idx +i)]
            end
        end
    end
end

--- Return true whether client B is in the right direction
-- compared to client A.
-- @param dir The direction.
-- @param cA The first client.
-- @param cB The second client.
-- @return True if B is in the direction of A.
local function is_in_direction(dir, cA, cB)
    if dir == "up" then
        return cA['y'] > cB['y']
    elseif dir == "down" then
        return cA['y'] < cB['y']
    elseif dir == "left" then
        return cA['x'] > cB['x']
    elseif dir == "right" then
        return cA['x'] < cB['x']
    end
    return false
end

--- Calculate distance between two points.
-- i.e: if we want to move to the right, we will take the right border
-- of the currently focused client and the left side of the checked client.
-- This avoid the focus of an upper client when you move to the right in a
-- tilebottom layout with nmaster=2 and 5 clients open, for instance.
-- @param dir The direction.
-- @param cA The first client.
-- @param cB The second client.
-- @return The distance between the clients.
local function calculate_distance(dir, cA, cB)
    local xA = cA['x']
    local xB = cB['x']
    local yA = cA['y']
    local yB = cB['y']

    if dir == "up" then
        yB = yB + cB['height']
    elseif dir == "down" then
        yA = yA + cA['height']
    elseif dir == "left" then
        xB = xB + cB['width']
    elseif dir == "right" then
        xA = xA + cA['width']
    end

    return math.sqrt(math.pow(xB - xA, 2) + math.pow(yB - yA, 2))
end

--- Focus a client by the given direction.
-- @param dir The direction, can be either "up", "down", "left" or "right".
-- @param c Optional client.
function client.focusbydirection(dir, c)
    local sel = c or capi.client.focus
    if sel then
        local coords = sel.coords
        local dist, dist_min
        local target = nil
        local cls = capi.client.visible_get(sel.screen)

        -- We check each client.
        for i, c in ipairs(cls) do
            -- Check coords to see if client is located in the right direction.
            if is_in_direction(dir, coords, c.coords) then

                -- Calculate distance between focused client and checked client.
                dist = calculate_distance(dir, coords, c.coords)

                -- If distance is shorter then keep the client.
                if not target or dist < dist_min then
                    target = c
                    dist_min = dist
                end
            end
        end

        -- If we found a client to focus, then do it.
        if target then
            capi.client.focus = target
        end
    end
end

--- Focus a client by its relative index.
-- @param i The index.
-- @param c Optional client.
function client.focusbyidx(i, c)
    local target = client.next(i, c)
    if target then
        capi.client.focus = target
    end
end

--- Swap a client by its relative index.
-- @param i The index.
-- @param c Optional client, otherwise focused one is used.
function client.swap(i, c)
    local sel = c or capi.client.focus
    local target = client.next(i, sel)
    if target then
        target:swap(sel)
    end
end

--- Get the master window.
-- @param screen Optional screen number, otherwise screen mouse is used.
-- @return The master window.
function client.master(screen)
    local s = screen or capi.mouse.screen
    return capi.client.visible_get(s)[1]
end

--- Move/resize a client relative to current coordinates.
-- @param x The relative x coordinate.
-- @param y The relative y coordinate.
-- @param w The relative width.
-- @param h The relative height.
-- @param c The optional client, otherwise focused one is used.
function client.moveresize(x, y, w, h, c)
    local sel = c or capi.client.focus
    local coords = sel.coords
    coords['x'] = coords['x'] + x
    coords['y'] = coords['y'] + y
    coords['width'] = coords['width'] + w
    coords['height'] = coords['height'] + h
    sel.coords = coords
end

--- Maximize a client to use the full workarea.
-- @param c A client, or the focused one if nil.
function client.maximize(c)
    local sel = c or capi.client.focus
    if sel then
        local ws = capi.screen[sel.screen].workarea
        ws.width = ws.width - 2 * sel.border_width
        ws.height = ws.height - 2 * sel.border_width
        if sel.floating and client.data.maximize[sel] then
            sel.floating = client.data.maximize[sel].floating
            if sel.floating then
                sel.coords = client.data.maximize[sel].coords
            end
            client.data.maximize[sel] = nil
        else
            client.data.maximize[sel] = { coords = sel.coords, floating = sel.floating }
            sel.floating = true
            sel.coords = ws
        end
    end
end


--- Erase eventual client data in maximize.
-- @param c The client.
local function client_maximize_clean(c)
    client.data.maximize[c] = nil
end

--- Give the focus to a screen, and move pointer.
-- @param Screen number.
function screen.focus(i)
    local s = cycle(capi.screen.count(), capi.mouse.screen + i)
    local c = client.focus.history.get(s, 0)
    if c then capi.client.focus = c end
    -- Move the mouse on the screen
    capi.mouse.screen = s
end

--- Compare 2 tables of tags.
-- @param a The first table.
-- @param b The second table of tags.
-- @return True if the tables are identical, false otherwise.
local function tag_compare_select(a, b)
    if not a or not b then
        return false
    end
    -- Quick size comparison
    if #a ~= #b then
        return false
    end
    for ka, va in pairs(a) do
        if b[ka] ~= va.selected then
            return false
        end
    end
    for kb, vb in pairs(b) do
        if a[kb].selected ~= vb then
            return false
        end
    end
    return true
end

--- Update the tag history.
-- @param screen The screen number.
function tag.history.update(screen)
    local curtags = capi.screen[screen]:tags()
    if not tag_compare_select(curtags, tag.history.data.current[screen]) then
        tag.history.data.past[screen] = tag.history.data.current[screen]
        tag.history.data.current[screen] = {}
        for k, v in ipairs(curtags) do
            tag.history.data.current[screen][k] = v.selected
        end
    end
end

-- Revert tag history.
-- @param screen The screen number.
function tag.history.restore(screen)
    local s = screen or capi.mouse.screen
    local tags = capi.screen[s]:tags()
    for k, t in pairs(tags) do
        t.selected = tag.history.data.past[s][k]
    end
end

--- Return a table with all visible tags
-- @param s Screen number.
-- @return A table with all selected tags.
function tag.selectedlist(s)
    local screen = s or capi.mouse.screen
    local tags = capi.screen[screen]:tags()
    local vtags = {}
    for i, t in pairs(tags) do
        if t.selected then
            vtags[#vtags + 1] = t
        end
    end
    return vtags
end

--- Return only the first visible tag.
-- @param s Screen number.
function tag.selected(s)
    return tag.selectedlist(s)[1]
end

--- Set master width factor.
-- @param mwfact Master width factor.
function tag.setmwfact(mwfact)
    local t = tag.selected()
    if t then
        t.mwfact = mwfact
    end
end

--- Increase master width factor.
-- @param add Value to add to master width factor.
function tag.incmwfact(add)
    local t = tag.selected()
    if t then
        t.mwfact = t.mwfact + add
    end
end

--- Set the number of master windows.
-- @param nmaster The number of master windows.
function tag.setnmaster(nmaster)
    local t = tag.selected()
    if t then
        t.nmaster = nmaster
    end
end

--- Increase the number of master windows.
-- @param add Value to add to number of master windows.
function tag.incnmaster(add)
    local t = tag.selected()
    if t then
        t.nmaster = t.nmaster + add
    end
end

--- Set number of column windows.
-- @param ncol The number of column.
function tag.setncol(ncol)
    local t = tag.selected()
    if t then
        t.ncol = ncol
    end
end

--- Increase number of column windows.
-- @param add Value to add to number of column windows.
function tag.incncol(add)
    local t = tag.selected()
    if t then
        t.ncol = t.ncol + add
    end
end

--- View no tag.
-- @param Optional screen number.
function tag.viewnone(screen)
    local tags = capi.screen[screen or capi.mouse.screen]:tags()
    for i, t in pairs(tags) do
        t.selected = false
    end
end

--- View a tag by its index.
-- @param i The relative index to see.
-- @param screen Optional screen number.
function tag.viewidx(i, screen)
    local tags = capi.screen[screen or capi.mouse.screen]:tags()
    local sel = tag.selected()
    tag.viewnone()
    for k, t in ipairs(tags) do
        if t == sel then
            tags[cycle(#tags, k + i)].selected = true
        end
    end
end

--- View next tag. This is the same as tag.viewidx(1).
function tag.viewnext()
    return tag.viewidx(1)
end

--- View previous tag. This is the same a tag.viewidx(-1).
function tag.viewprev()
    return tag.viewidx(-1)
end

--- View only a tag.
-- @param t The tag object.
function tag.viewonly(t)
    tag.viewnone(t.screen)
    t.selected = true
end

--- View only a set of tags.
-- @param tags A table with tags to view only.
-- @param screen Optional screen number of the tags.
function tag.viewmore(tags, screen)
    tag.viewnone(screen)
    for i, t in pairs(tags) do
        t.selected = true
    end
end

--- Move a client to a tag.
-- @param target The tag to move the client to.
-- @para c Optional client to move, otherwise the focused one is used.
function client.movetotag(target, c)
    local sel = c or capi.client.focus
    if sel then
        -- Check that tag and client screen are identical
        if sel.screen ~= target.screen then return end
        sel:tags({ target })
    end
end

--- Toggle a tag on a client.
-- @param target The tag to toggle.
-- @param c Optional client to toggle, otherwise the focused one is used.
function client.toggletag(target, c)
    local sel = c or capi.client.focus
    -- Check that tag and client screen are identical
    if sel and sel.screen == target.screen then
        local tags = sel:tags()
        if tags[target] then
            tags[target] = nil
        else
            tags[target] = target
        end
        sel:tags(tags)
    end
end

--- Toggle the floating status of a client.
-- @param c Optional client, the focused on if not set.
function client.togglefloating(c)
    local sel = c or capi.client.focus
    if sel then
        sel.floating = not sel.floating
    end
end

--- Move a client to a screen. Default is next screen, cycling.
-- @param c The client to move.
-- @param s The screen number, default to current + 1.
function client.movetoscreen(c, s)
    local sel = c or capi.client.focus
    if sel then
        local sc = capi.screen.count()
        if not s then
            s = sel.screen + 1
        end
        if s > sc then s = 1 elseif s < 1 then s = sc end
        sel.screen = s
        capi.mouse.coords = capi.screen[s].coords
        capi.client.focus = sel
    end
end

--- Get the current layout name.
-- @param screen The screen number.
function layout.get(screen)
    local t = tag.selected(screen)
    if t then
        return t.layout
    end
end

--- Create a new userhook (for external libs).
-- @param name Hook name.
function hooks.user.create(name)
    hooks[name] = {}
    hooks[name].callbacks = {}
    hooks[name].register = function (f)
        table.insert(hooks[name].callbacks, f)
    end
    hooks[name].unregister = function (f)
        for k, h in ipairs(hooks[name].callbacks) do
            if h == f then
                table.remove(hooks[name].callbacks, k)
                break
            end
        end
    end
end

--- Call a created userhook (for external libs).
-- @param name Hook name.
function hooks.user.call(name, ...)
    for name, callback in pairs(hooks[name].callbacks) do
        callback(...)
    end
end

-- Just set an awful mark to a client to move it later.
local awfulmarked = {}
hooks.user.create('marked')
hooks.user.create('unmarked')

--- Mark a client, and then call 'marked' hook.
-- @param c The client to mark, the focused one if not specified.
-- @return True if the client has been marked. False if the client was already marked.
function client.mark (c)
    local cl = c or capi.client.focus
    if cl then
        for k, v in pairs(awfulmarked) do
            if cl == v then
                return false
            end
        end

        table.insert(awfulmarked, cl)

        -- Call callback
        hooks.user.call('marked', cl)
        return true
    end
end

--- Unmark a client and then call 'unmarked' hook.
-- @param c The client to unmark, or the focused one if not specified.
-- @return True if the client has been unmarked. False if the client was not marked.
function client.unmark(c)
    local cl = c or capi.client.focus

    for k, v in pairs(awfulmarked) do
        if cl == v then
            table.remove(awfulmarked, k)
            hooks.user.call('unmarked', cl)
            return true
        end
    end

    return false
end

--- Check if a client is marked.
-- @param c The client to check, or the focused one otherwise.
function client.ismarked(c)
    local cl = c or capi.client.focus
    if cl then
        for k, v in pairs(awfulmarked) do
            if cl == v then
                return true
            end
        end
    end
    return false
end

--- Toggle a client as marked.
-- @param c The client to toggle mark.
function client.togglemarked(c)
    local cl = c or capi.client.focus

    if not client.mark(c) then
        client.unmark(c)
    end
end

--- Return the marked clients and empty the marked table.
-- @return A table with all marked clients.
function client.getmarked()
    for k, v in pairs(awfulmarked) do
        hooks.user.call('unmarked', v)
    end

    t = awfulmarked
    awfulmarked = {}
    return t
end

--- Change the layout of the current tag.
-- @param layouts A table of layouts.
-- @param i Relative index.
function layout.inc(layouts, i)
    local t = tag.selected()
    local number_of_layouts = 0
    local rev_layouts = {}
    for i, v in ipairs(layouts) do
        rev_layouts[v] = i
        number_of_layouts = number_of_layouts + 1
    end
    if t then
        local cur_layout = layout.get()
        local new_layout_index = (rev_layouts[cur_layout] + i) % number_of_layouts
        if new_layout_index == 0 then
            new_layout_index = number_of_layouts
        end
        t.layout = layouts[new_layout_index]
    end
end

--- Set the layout of the current tag by name.
-- @param layout Layout name.
function layout.set(layout)
    local t = tag.selected()
    if t then
        t.layout = layout
    end
end

-- Autodeclare awful.hooks.* functions
-- mapped to awesome hooks.* functions
for name, hook in pairs(capi.hooks) do
    if name ~= 'timer' then
        hooks[name] = {}
        hooks[name].register = function (f)
            if not hooks[name].callbacks then
                hooks[name].callbacks = {}
                hook(function (...)
                    for i, callback in ipairs(hooks[name].callbacks) do
                       callback(...)
                    end
                end)
            end

            table.insert(hooks[name].callbacks, f)
        end
        hooks[name].unregister = function (f)
            if hooks[name].callbacks then
                for k, h in ipairs(hooks[name].callbacks) do
                    if h == f then
                        table.remove(hooks[name].callbacks, k)
                        break
                    end
                end
            end
        end
    else
        hooks[name] = {}
        hooks[name].register = function (time, f, runnow)
            if type(time) ~= 'number' or type(f) ~= 'function' or time <= 0 then
                return
            end
            local new_timer
            if hooks[name].timer then
                -- Take the smallest between current and new
                new_timer = math.min(time, hooks[name].timer)
            else
                new_timer = time
            end
            if not hooks[name].callbacks then
                hooks[name].callbacks = {}
            end
            if hooks[name].timer ~= new_timer then
                hooks[name].timer = new_timer
                hook(hooks[name].timer, function (...)
                    for i, callback in ipairs(hooks[name].callbacks) do
                        callback['counter'] = callback['counter'] + hooks[name].timer
                        if callback['counter'] >= callback['timer'] then
                            callback['callback'](...)
                            callback['counter'] = 0
                        end
                    end
                end)
            end

            if runnow then
                table.insert(hooks[name].callbacks, { callback = f, timer = time, counter = time })
            else
                table.insert(hooks[name].callbacks, { callback = f, timer = time, counter = 0 })
            end
        end
        hooks[name].unregister = function (f)
            if hooks[name].callbacks then
                for k, h in ipairs(hooks[name].callbacks) do
                    if h.callback == f then
                        table.remove(hooks[name].callbacks, k)
                        break
                    end
                end
            end
        end
    end
end

--- Spawn a program.
-- @param cmd The command.
-- @return The awesome.spawn return value.
function spawn(cmd)
    if cmd and cmd ~= "" then
        return capi.awesome.spawn(cmd .. "&", capi.mouse.screen)
    end
end

--- Eval Lua code.
-- @return The return value of Lua code.
function eval(s)
    return assert(loadstring("return " .. s))()
end

--- Load history file in history table
-- @param id The prompt history identifier which is the path to the filename
-- @param max Optional parameter, the maximum number of entries in file
local function prompt_history_check_load(id, max)
    if id and id ~= ""
        and not prompt.history[id] then
	prompt.history[id] = { max = 50, table = {} }

	if max then
            prompt.history[id].max = max
	end

	local f = io.open(id, "r")

	-- Read history file
	if f then
            for line in f:lines() do
                table.insert(prompt.history[id].table, line)
                if #prompt.history[id].table >= prompt.history[id].max then
                   break
		end
            end
	end
    end
end

--- Save history table in history file
-- @param id The prompt history identifier
local function prompt_history_save(id)
    if prompt.history[id] then
        local f = assert(io.open(id, "w"))
	for i = 1, math.min(#prompt.history[id].table, prompt.history[id].max) do
            f:write(prompt.history[id].table[i] .. "\n")
        end
       f:close()
    end
end

--- Return the number of items in history table regarding the id
-- @param id The prompt history identifier
-- @return the number of items in history table, -1 if history is disabled
local function prompt_history_items(id)
    if prompt.history[id] then
        return #prompt.history[id].table
    else
        return -1
    end
end

--- Add an entry to the history file
-- @param id The prompt history identifier
-- @param command The command to add
local function prompt_history_add(id, command)
    if prompt.history[id] then
        if command ~= ""
            and command ~= prompt.history[id].table[#prompt.history[id].table] then
            table.insert(prompt.history[id].table, command)

            -- Do not exceed our max_cmd
            if #prompt.history[id].table > prompt.history[id].max then
                table.remove(prompt.history[id].table, 1)
            end

            prompt_history_save(id)
        end
    end
end

--- Use bash completion system to complete command and filename.
-- @param command The command line.
-- @param cur_pos The cursor position.
-- @paran ncomp The element number to complete.
-- @return The new command and the new cursor position.
function completion.bash(command, cur_pos, ncomp)
    local wstart = 1
    local wend = 1
    local words = {}
    local cword_index = 0
    local cword_start = 0
    local cword_end = 0
    local i = 1
    local comptype = "file"

    -- do nothing if we are on a letter, i.e. not at len + 1 or on a space
    if cur_pos ~= #command + 1 and command:sub(cur_pos, cur_pos) ~= " " then
        return command, cur_pos
    elseif #command == 0 then
        return command, cur_pos
    end

    while wend <= #command do
        wend = command:find(" ", wstart)
        if not wend then wend = #command + 1 end
        table.insert(words, command:sub(wstart, wend - 1))
        if cur_pos >= wstart and cur_pos <= wend + 1 then
            cword_start = wstart
            cword_end = wend
            cword_index = i
        end
        wstart = wend + 1
        i = i + 1
    end

    if cword_index == 1 then
        comptype = "command"
    end

    local c = io.popen("/usr/bin/env bash -c 'compgen -A " .. comptype .. " " .. words[cword_index] .. "'")
    local output = {}
    i = 0
    while true do
        local line = c:read("*line")
        if not line then break end
        table.insert(output, line)
    end

    c:close()

    -- no completion, return
    if #output == 0 then
        return command, cur_pos
    end

    -- cycle
    while ncomp > #output do
        ncomp = ncomp - #output
    end

    local str = command:sub(1, cword_start - 1) .. output[ncomp] .. command:sub(cword_end)
    cur_pos = cword_end + #output[ncomp] + 1

    return str, cur_pos
end

--- Draw the prompt text with a cursor.
-- @param text The text.
-- @param text_color The text color.
-- @param cursor_color The cursor color.
-- @param cursor_pos The cursor position.
local function prompt_text_with_cursor(text, text_color, cursor_color, cursor_pos)
    local char
    if not text then text = "" end
    if #text < cursor_pos then
        char = " "
    else
        char = escape(text:sub(cursor_pos, cursor_pos))
    end
    local text_start = escape(text:sub(1, cursor_pos - 1))
    local text_end = escape(text:sub(cursor_pos + 1))
    return text_start .. "<span background=\"" .. cursor_color .. "\" foreground=\"" .. text_color .. "\">" .. char .. "</span>" .. text_end
end

--- Run a prompt in a box.
-- @param args A table with optional arguments: fg_cursor, bg_cursor, prompt.
-- @param textbox The textbox to use for the prompt.
-- @param exe_callback The callback function to call with command as argument when finished.
-- @param completion_callback The callback function to call to get completion.
-- @param history_path Optional parameter: file path where the history should be saved, set nil to disable history
-- @param history_max Optional parameter: set the maximum entries in history file, 50 by default
-- @param done_callback Optional parameter: the callback function to always call without arguments, regardless of whether the prompt was cancelled.
function prompt.run(args, textbox, exe_callback, completion_callback, history_path, history_max, done_callback)
    if not args then args = {} end
    local command = ""
    local command_before_comp
    local cur_pos_before_comp
    local prettyprompt = args.prompt or ""
    local inv_col = args.fg_cursor or theme.fg_focus or "black"
    local cur_col = args.bg_cursor or theme.bg_focus or "white"

    prompt_history_check_load(history_path, history_max)
    local history_index = prompt_history_items(history_path) + 1
    -- The cursor position
    local cur_pos = 1
    -- The completion element to use on completion request.
    local ncomp = 1
    if not textbox or not exe_callback then
        return
    end
    textbox.text = prettyprompt .. prompt_text_with_cursor(text, inv_col, cur_col, cur_pos)
    capi.keygrabber.run(
    function (mod, key)
        local has_ctrl = false

        -- Compute modifiers keys
        for k, v in ipairs(mod) do
            if v == "Control" then has_ctrl = true end
        end

        -- Get out cases
        if has_ctrl then
            if key == "c" or key == "g" then
                textbox.text = ""
                if done_callback then done_callback() end
                return false
            elseif key == "j" or key == "m" then
                textbox.text = ""
                exec_callback(command)
                if done_callback then done_callback() end
                return false
            end
        else
            if key == "Return" then
                textbox.text = ""
                prompt_history_add(history_path, command)
                exe_callback(command)
                if done_callback then done_callback() end
                return false
            elseif key == "Escape" then
                textbox.text = ""
                if done_callback then done_callback() end
                return false
            end
        end

        -- Control cases
        if has_ctrl then
            if key == "a" then
                cur_pos = 1
            elseif key == "b" then
                if cur_pos > 1 then
                    cur_pos = cur_pos - 1
                end
            elseif key == "d" then
                if cur_pos <= #command then
                    command = command:sub(1, cur_pos - 1) .. command:sub(cur_pos + 1)
                end
            elseif key == "e" then
                cur_pos = #command + 1
            elseif key == "f" then
                if cur_pos <= #command then
                    cur_pos = cur_pos + 1
                end
            elseif key == "h" then
                if cur_pos > 1 then
                    command = command:sub(1, cur_pos - 2) .. command:sub(cur_pos)
                    cur_pos = cur_pos - 1
                end
            elseif key == "k" then
                command = command:sub(1, cur_pos - 1)
            elseif key == "u" then
                command = command:sub(cur_pos, #command)
                cur_pos = 1
            elseif key == "w" then
                local wstart = 1
                local wend = 1
                local cword_start = 1
                local cword_end = 1
                while wend < cur_pos do
                    wend = command:find(" ", wstart)
                    if not wend then wend = #command + 1 end
                    if cur_pos >= wstart and cur_pos <= wend + 1 then
                        cword_start = wstart
                        cword_end = cur_pos - 1
                        break
                    end
                    wstart = wend + 1
                end
                command = command:sub(1, cword_start - 1) .. command:sub(cword_end + 1)
                cur_pos = cword_start
            end
        else
            if completion_callback then
                -- That's tab
                if key:byte() == 9 then
                    if ncomp == 1 then
                        command_before_comp = command
                        cur_pos_before_comp = cur_pos
                    end
                    command, cur_pos = completion_callback(command_before_comp, cur_pos_before_comp, ncomp)
                    ncomp = ncomp + 1
                    key = ""
                else
                    ncomp = 1
                end
            end

            -- Typin cases
            if key == "Home" then
                cur_pos = 1
            elseif key == "End" then
                cur_pos = #command + 1
            elseif key == "BackSpace" then
                if cur_pos > 1 then
                    command = command:sub(1, cur_pos - 2) .. command:sub(cur_pos)
                    cur_pos = cur_pos - 1
                end
            -- That's DEL
            elseif key:byte() == 127 then
                command = command:sub(1, cur_pos - 1) .. command:sub(cur_pos + 1)
            elseif key == "Left" then
                cur_pos = cur_pos - 1
            elseif key == "Right" then
                cur_pos = cur_pos + 1
            elseif key == "Up" then
                if history_index > 1 then
                    history_index = history_index - 1

                    command = prompt.history[history_path].table[history_index]
                    cur_pos = #command + 2
                end
            elseif key == "Down" then
               if history_index < prompt_history_items(history_path) then
                    history_index = history_index + 1

                    command = prompt.history[history_path].table[history_index]
                    cur_pos = #command + 2
                elseif history_index == prompt_history_items(history_path) then
                    history_index = history_index + 1

                    command = ""
                    cur_pos = 1
                end
            else
                -- len() is UTF-8 aware but #key is not,
                -- so check that we have one UTF-8 char but advance the cursor of # position
                if key:len() == 1 then
                    command = command:sub(1, cur_pos - 1) .. key .. command:sub(cur_pos)
                    cur_pos = cur_pos + #key
                end
            end
            if cur_pos < 1 then
                cur_pos = 1
            elseif cur_pos > #command + 1 then
                cur_pos = #command + 1
            end
        end

        -- Update textbox
        textbox.text = prettyprompt .. prompt_text_with_cursor(command, inv_col, cur_col, cur_pos)

        return true
    end)
end

--- Escape a string from XML char.
-- Useful to set raw text in textbox.
-- @param text Text to escape.
-- @return Escape text.
function escape(text)
    if text then
        text = text:gsub("&", "&amp;")
        text = text:gsub("<", "&lt;")
        text = text:gsub(">", "&gt;")
        text = text:gsub("'", "&apos;")
        text = text:gsub("\"", "&quot;")
    end
    return text
end

--- Unescape a string from entities.
-- @param text Text to unescape.
-- @return Unescaped text.
function unescape(text)
    if text then
        text = text:gsub("&amp;", "&")
        text = text:gsub("&lt;", "<")
        text = text:gsub("&gt;", ">")
        text = text:gsub("&apos;", "'")
        text = text:gsub("&quot;", "\"")
    end
    return text
end

--- Return labels for a taglist widget with all tag from screen.
-- It returns the tag name and set a special
-- foreground and background color for selected tags.
-- @param t The tag.
-- @param args The arguments table.
-- bg_focus The background color for selected tag.
-- fg_focus The foreground color for selected tag.
-- bg_urgent The background color for urgent tags.
-- fg_urgent The foreground color for urgent tags.
-- taglist_squares Optional: set "true" or nil to display the taglist squares.
-- @return A string to print.
function widget.taglist.label.all(t, args)
    if not args then args = {} end
    local fg_focus = args.fg_focus or theme.taglist_fg_focus or theme.fg_focus
    local bg_focus = args.bg_focus or theme.taglist_bg_focus or theme.bg_focus
    local fg_urgent = args.fg_urgent or theme.taglist_fg_urgent or theme.fg_urgent
    local bg_urgent = args.bg_urgent or theme.taglist_bg_urgent or theme.bg_urgent
    local taglist_squares = args.taglist_squares or theme.taglist_squares
    local text
    local background = ""
    local sel = capi.client.focus
    local bg_color = nil
    local fg_color = nil
    if t.selected then
        bg_color = bg_focus
        fg_color = fg_focus
    end
    if sel and sel:tags()[t] then
        if not taglist_squares or taglist_squares == "true" then
            background = "resize=\"true\" image=\"@AWESOME_ICON_PATH@/taglist/squarefw.png\""
        end
    elseif bg_urgent and fg_urgent then
        for k, c in pairs(t:clients()) do
            if not taglist_squares or taglist_squares == "true" then
                background = "resize=\"true\" image=\"@AWESOME_ICON_PATH@/taglist/squarew.png\""
            end
            if c.urgent then
                bg_color = bg_urgent
                fg_color = fg_urgent
                break
            end
        end
    end
    if bg_color and fg_color then
        text = "<bg "..background.." color='"..bg_color.."'/> <span color='"..fg_color.."'>"..escape(t.name).."</span> "
    else
        text = " <bg "..background.." />"..escape(t.name).." "
    end
    return text
end

--- Return labels for a taglist widget with all *non empty* tags from screen.
-- It returns the tag name and set a special
-- foreground and background color for selected tags.
-- @param t The tag.
-- @param args The arguments table.
-- bg_focus The background color for selected tag.
-- fg_focus The foreground color for selected tag.
-- bg_urgent The background color for urgent tags.
-- fg_urgent The foreground color for urgent tags.
-- @return A string to print.
function widget.taglist.label.noempty(t, args)
    if #t:clients() > 0 or t.selected then
        if not args then args = {} end
        local fg_focus = args.fg_focus or theme.taglist_fg_focus or theme.fg_focus
        local bg_focus = args.bg_focus or theme.taglist_bg_focus or theme.bg_focus
        local fg_urgent = args.fg_urgent or theme.taglist_fg_urgent or theme.fg_urgent
        local bg_urgent = args.bg_urgent or theme.taglist_bg_urgent or theme.bg_urgent
        local bg_color = nil
        local fg_color = nil
        local text

        if t.selected then
            bg_color = bg_focus
            fg_color = fg_focus
        end
        if bg_urgent and fg_urgent then
            for k, c in pairs(t:clients()) do
                if c.urgent then
                    bg_color = bg_urgent
                    fg_color = fg_urgent
                    break
                end
            end
        end
        if fg_color and bg_color then
            text = "<bg color='" .. bg_color .. "'/> <span color='" .. fg_color .. "'>" .. escape(t.name) .. "</span> "
        else
            text = " " .. escape(t.name) .. " "
        end
        return text
    end
end

local function widget_tasklist_label_common(c, args)
    if not args then args = {} end
    local fg_focus = args.fg_focus or theme.tasklist_fg_focus or theme.fg_focus
    local bg_focus = args.bg_focus or theme.tasklist_bg_focus or theme.bg_focus
    local fg_urgent = args.fg_urgent or theme.tasklist_fg_urgent or theme.fg_urgent
    local bg_urgent = args.bg_urgent or theme.tasklist_bg_urgent or theme.bg_urgent
    local text = ""
    local name
    if c.floating then
        text = "<bg image=\"@AWESOME_ICON_PATH@/tasklist/floatingw.png\" align=\"right\"/>"
    end
    if c.hidden then
        name = escape(c.icon_name) or ""
    else
        name = escape(c.name) or ""
    end
    if capi.client.focus == c then
        text = text .. " <bg color='"..bg_focus.."'/><span color='"..fg_focus.."'>"..name.."</span> "
    elseif c.urgent and bg_urgent and fg_urgent then
        text = text .. " <bg color='"..bg_urgent.."'/><span color='"..fg_urgent.."'>"..name.."</span> "
    else
        text = text .. " "..name.." "
    end
    return text
end

--- Return labels for a tasklist widget with clients from all tags and screen.
-- It returns the client name and set a special
-- foreground and background color for focused client.
-- It also puts a special icon for floating windows.
-- @param c The client.
-- @param screen The screen we are drawing on.
-- @param args The arguments table.
-- bg_focus The background color for focused client.
-- fg_focus The foreground color for focused client.
-- bg_urgent The background color for urgent clients.
-- fg_urgent The foreground color for urgent clients.
-- @return A string to print.
function widget.tasklist.label.allscreen(c, screen, args)
    return widget_tasklist_label_common(c, args)
end

--- Return labels for a tasklist widget with clients from all tags.
-- It returns the client name and set a special
-- foreground and background color for focused client.
-- It also puts a special icon for floating windows.
-- @param c The client.
-- @param screen The screen we are drawing on.
-- @param args The arguments table.
-- bg_focus The background color for focused client.
-- fg_focus The foreground color for focused client.
-- bg_urgent The background color for urgent clients.
-- fg_urgent The foreground color for urgent clients.
-- @return A string to print.
function widget.tasklist.label.alltags(c, screen, args)
    -- Only print client on the same screen as this widget
    if c.screen ~= screen then return end
    return widget_tasklist_label_common(c, args)
end

--- Return labels for a tasklist widget with clients from currently selected tags.
-- It returns the client name and set a special
-- foreground and background color for focused client.
-- It also puts a special icon for floating windows.
-- @param c The client.
-- @param screen The screen we are drawing on.
-- @param args The arguments table.
-- bg_focus The background color for focused client.
-- fg_focus The foreground color for focused client.
-- bg_urgent The background color for urgent clients.
-- fg_urgent The foreground color for urgent clients.
-- @return A string to print.
function widget.tasklist.label.currenttags(c, screen, args)
    -- Only print client on the same screen as this widget
    if c.screen ~= screen then return end
    for k, t in ipairs(capi.screen[screen]:tags()) do
        if t.selected and c:tags()[t] then
            return widget_tasklist_label_common(c, args)
        end
    end
end

--- Create a standard titlebar.
-- @param c The client.
-- @param args Arguments.
-- fg: the foreground color.
-- bg: the background color.
-- fg_focus: the foreground color for focused window.
-- fg_focus: the background color for focused window.
function titlebar.add(c, args)
    if not args then args = {} end
    -- Store colors
    titlebar.data[c] = {}
    titlebar.data[c].fg = args.fg or theme.titlebar_fg_normal or theme.fg_normal
    titlebar.data[c].bg = args.bg or theme.titlebar_bg_normal or theme.bg_normal
    titlebar.data[c].fg_focus = args.fg_focus or theme.titlebar_fg_focus or theme.fg_focus
    titlebar.data[c].bg_focus = args.bg_focus or theme.titlebar_bg_focus or theme.bg_focus

    -- Built args
    local targs = {}
    if args.fg then targs.fg = args.fg end
    if args.bg then targs.bg = args.bg end
    local tb = capi.titlebar(targs)

    local title = capi.widget({ type = "textbox", name = "title", align = "flex" })
    title:mouse_add(capi.mouse({ }, 1, function (t) t.client:mouse_move() end))
    title:mouse_add(capi.mouse({ args.modkey }, 3, function (t) t.client:mouse_resize() end))

    local close_button= capi.widget({ type = "textbox", name = "close", align = "right" })
    close_button:mouse_add(capi.mouse({ }, 1, function (t) t.client:kill() end))

    tb.widgets =
    {
        capi.widget({ type = "appicon", name = "appicon", align = "left" }),
        title,
        close_button
    }

    titlebar.update(c)

    c.titlebar = tb
end

--- Update a titlebar. This should be called in some hooks.
-- @param c The client to update.
function titlebar.update(c)
    if c.titlebar and titlebar.data[c] then
        local widgets = c.titlebar.widgets
        local title, close
        for k, v in ipairs(widgets) do
            if v.name == "title" then title = v end
            if v.name == "close" then close = v end
            if title and close then break end
        end
        if title then
            title.text = " " .. escape(c.name)
        end
        if capi.client.focus == c then
            c.titlebar.fg = titlebar.data[c].fg_focus
            c.titlebar.bg = titlebar.data[c].bg_focus
            if close then
                close.text = "<bg image=\"@AWESOME_ICON_PATH@/titlebar/closer.png\" resize=\"true\"/>"
            end
        else
            c.titlebar.fg = titlebar.data[c].fg
            c.titlebar.bg = titlebar.data[c].bg
            if close then
                close.text = "<bg image=\"@AWESOME_ICON_PATH@/titlebar/close.png\" resize=\"true\"/>"
            end
        end
    end
end

--- Remove a titlebar from a client.
-- @param c The client.
function titlebar.remove(c)
    c.titlebar = nil
    titlebar.data[c] = nil
end

--- Set the beautiful theme if any.
-- @param The beautiful theme.
function beautiful.register(btheme)
    if btheme then
        theme = btheme
    else
        theme = {}
    end
end

-- Register standards hooks
hooks.arrange.register(tag.history.update)

hooks.focus.register(client.focus.history.add)
hooks.unmanage.register(client.focus.history.delete)
hooks.unmanage.register(client_maximize_clean)

hooks.focus.register(titlebar.update)
hooks.unfocus.register(titlebar.update)
hooks.titleupdate.register(titlebar.update)
hooks.unmanage.register(titlebar.remove)

hooks.urgent.register(client.urgent.stack.add)
hooks.focus.register(client.urgent.stack.delete)
hooks.unmanage.register(client.urgent.stack.delete)

-- vim: filetype=lua:expandtab:shiftwidth=4:tabstop=8:softtabstop=4:encoding=utf-8:textwidth=80