local P = {}
local Widget = require("desktop.layoutmanager.widget")
P.__index = P

-- screen.layouts, awful.layouts, and tag.layouts are all ignored.
-- This module replaces the standard layout functions.

function P:new(screen)
	local l = {
		layouts = conf.layouts,
		screen = screen.screen
	}
	setmetatable(l, self)


	l._widget = Widget:new(l)
	l.widget = l._widget.widget

	return l

	--[[ Example
	conf.layouts = {
		{
			awful.layout.suit.tile.left,
			awful.layout.suit.tile,
		},
		{
			awful.layout.suit.fair,
			awful.layout.suit.fair.horizontal,
		},
		{
			awful.layout.suit.floating,
		}
	}
	--]]
end

-- Find layout in self.layouts
-- Returns group index, alt index
function P:find_layout(layout)
	for k, v in pairs(self.layouts) do
		for l, m in pairs(v) do
			if (layout == m) then
				return k, l
			end
		end
	end
end

function P:get_default_layout()
	return self.layouts[1][1]
end

-- Change layout group
function P:change_group(step)
	local tag = self.screen.selected_tag	-- Multiple selected tags are NOT supported!
	local layout = tag.layout

	-- Subtract 1, lua doesn't start at 0
	local g, a
	g, a = self:find_layout(layout)
	g = g - 1


	g = ((g + step) % #self.layouts) + 1

	awful.layout.set(self.layouts[g][1], tag)
end

-- Change layout alternate
function P:change_alt(step)
	local tag = self.screen.selected_tag	-- Multiple selected tags are NOT supported!
	local layout = tag.layout

	-- Subtract 1, lua doesn't start at 0
	local g, a
	g, a = self:find_layout(layout)
	a = a - 1


	a = ((a + step) % #self.layouts[g]) + 1

	awful.layout.set(self.layouts[g][a], tag)
end

function P:next()
	self:change_group(1)
end
function P:prev()
	self:change_group(-1)
end
function P:next_alt()
	self:change_alt(1)
end
function P:prev_alt()
	self:change_alt(-1)
end

return P