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

-- Grab environment we need
local setmetatable = setmetatable
local ipairs = ipairs
local math = math
local client = require("awful.client")
local tag = require("awful.tag")
local capi =
{
    screen = screen
}

--- Tiled layouts module for awful
module("awful.layout.suit.tile")

local function tile(_, screen, position)
    if not position then position = "right" end
    local t = tag.selected()
    local nmaster = tag.getnmaster(t)
    local mwfact = tag.getmwfact(t)
    local ncol = tag.getncol(t)

    local wa = capi.screen[screen].workarea
    local cls = client.tiled(screen)

    local masterwin = math.min(#cls, nmaster)
    local otherwin = math.max(#cls - masterwin, 0);

    local mh, mw
    if nmaster > 0 then
        if position == "right" or position == "left" then
            if masterwin > 0 then
                mh = wa.height / masterwin
            else
                mh = wa.height
            end
            if otherwin > 0 then
                mw = wa.width * mwfact
            else
                mw = wa.width
            end
        else
            if otherwin > 0 then
                mh = wa.height * mwfact
            else
                mh = wa.height
            end
            if masterwin > 0 then
                mw = wa.width / masterwin
            else
                mw = wa.width
            end
        end
    else
        mh = 0
        mw = 0
    end

    local real_ncol
    if ncol > 0 then
        real_ncol = math.min(otherwin, ncol)
    else
        real_ncol = math.min(otherwin, 1)
    end

    for i, c in ipairs(cls) do
        local geometry = {}

        -- Master windows
        if i <= nmaster then
            if position == "right" then
                geometry.y = wa.y + (i - 1) * mh
                geometry.x = wa.x
            elseif position == "left" then
                geometry.y = wa.y + (i - 1) * mh
                geometry.x = wa.x + (wa.width - mw)
            elseif position == "top" then
                geometry.x = wa.x + (i - 1) * mw
                geometry.y = wa.y + (wa.height - mh)
            else
                geometry.x = wa.x + (i - 1) * mw
                geometry.y = wa.y
            end

            geometry.width = mw
            geometry.height = mh

        -- Slave windows
        else
            local win_by_col = math.ceil(otherwin / real_ncol)
            real_ncol = math.ceil(otherwin / win_by_col)
            local current_col = math.floor((i - 1 - nmaster) / win_by_col)

            if position == "right" or position == "left" then
                if otherwin <= real_ncol then
                    geometry.height = wa.height
                elseif (otherwin % win_by_col) ~= 0 and (current_col == real_ncol - 1) then
                    geometry.height = math.floor(wa.height / (otherwin % win_by_col))
                else
                    geometry.height = math.floor(wa.height / win_by_col)
                end

                geometry.width = math.floor((wa.width - mw) / real_ncol)

                if otherwin <= real_ncol then
                    geometry.y = wa.y
                else
                    geometry.y = wa.y + ((i - 1 - nmaster) % win_by_col) *
                                        geometry.height
                end
                geometry.x = wa.x + current_col * geometry.width

                if position == "right" then
                    geometry.x = geometry.x + mw
                end
            else
                if otherwin <= real_ncol then
                    geometry.width = wa.width
                elseif (otherwin % win_by_col) ~= 0 and (current_col == real_ncol - 1) then
                    geometry.width = math.floor(wa.width / (otherwin % win_by_col))
                else
                    geometry.width = math.floor(wa.width / win_by_col)
                end

                geometry.height = math.floor((wa.height - mh) /  real_ncol)

                if otherwin <= real_ncol then
                    geometry.x = wa.x
                else
                    geometry.x = wa.x + ((i - 1 - nmaster) % win_by_col) *
                                        geometry.width
                end

                geometry.y = wa.y + current_col * geometry.height

                if position == "bottom" then
                    geometry.y = geometry.y + mh
                end
            end
        end
        c:geometry(geometry)
    end
end

--- The main tile algo, on left.
-- @param screen The screen number to tile.
function left(screen)
    return tile(nil, screen, "left")
end

--- The main tile algo, on bottom.
-- @param screen The screen number to tile.
function bottom(screen)
    return tile(nil, screen, "bottom")
end

--- The main tile algo, on top.
-- @param screen The screen number to tile.
function top(screen)
    return tile(nil, screen, "top")
end

setmetatable(_M, { __call = tile })