-- Tag grid manager

local Tagger = {
	screen = nil, rows = 2, cols = 4
}
Tagger.__index = Tagger

function Tagger:new(screen)
	local t = {}
	setmetatable(t, Tagger)
	t.screen = screen

	-- Create tags on this Tagger's screen
	for r=1, t.rows do
		for c=1, t.cols do
			awful.tag.add("(" .. tostring(r) .. ", " .. tostring(c) .. ")", {
				layout = layoutmanager:default_layout(),
				screen = t.screen,

				gap_single_client = false,
				gap = beautiful.useless_gap,
				volatile = false,

				-- Only select the first tag
				selected = ((r == 1) and (c == 1))
			})
		end
	end
	return t
end


function Tagger:get_tag()
	return self.screen.selected_tag.index
end

-- Return current column
function Tagger:get_col()
	return ( (self:get_tag() - 1) % self.cols ) + 1
end

-- Return current row
function Tagger:get_row()
	return math.floor( (self:get_tag() - self:get_col()) / self.cols ) + 1
end

-- Select a tag by position
function Tagger:setpos(row, col)
	local target_absolute = (self.cols * (row - 1)) + col
	local target_relative = target_absolute - self.screen.selected_tag.index
	awful.tag.viewidx(target_relative)

	self:update_widget()
end

-- Update this tagger's screen's tagindicator
function Tagger:update_widget()
	local clients
	local tgs = self.screen.tags

	for i=1, #tgs do
		clients = tgs[i]:clients()

		-- Each tag indicator is a "checkbox" widget.
		--  Make that the currently active tag is checked and that all
		--  others are not.
		if (tgs[i].index == self.screen.selected_tag.index) then
			self.screen.tagindicators[i].checked = true
		else
			self.screen.tagindicators[i].checked = false
		end

		-- Highlight tags that are not empty
		if (#clients == 0) then
			self.screen.tagindicators[i].border_color = beautiful.color.bar.inactive
		else
			self.screen.tagindicators[i].border_color = beautiful.color.bar.active
		end
	end
end

-- Navigation
function Tagger:up()
	local row = self:get_row() - 1
	local col = self:get_col()

	if (row >= 1) then
		self:setpos(row, col)
	end
end

function Tagger:down()
	local row = self:get_row() + 1
	local col = self:get_col()

	if (row <= self.rows) then
		self:setpos(row, col)
	end
end

function Tagger:right()
	local row = self:get_row()
	local col = self:get_col() + 1

	if (col <= self.cols) then
		self:setpos(row, col)
	end
end

function Tagger:left()
	local row = self:get_row()
	local col = self:get_col() - 1

	if (col >= 1) then
		self:setpos(row, col)
	end
end



-- Moving clients
function Tagger:move_client(client, direction)
	if direction == "up" then
		self:up()
	elseif direction == "down" then
		self:down()
	elseif direction == "left" then
		self:left()
	elseif direction == "right" then
		self:right()
	end

	if client.first_tag.layout == awful.layout.suit.floating then
		client.floating = true
	end

	client:move_to_tag(self.screen.selected_tag)
	self:update_widget()
end

return Tagger