local array = require "util.array";

local it = require "util.iterators";

local curses = require "curses";

local stats = module:require "stats".stats;

local time = require "socket".gettime;

local sessions_idle_after = 60;

local stanza_names = {"message", "presence", "iq"};

local top = {};

top.__index = top;

local status_lines = {

	"Prosody $version - $time up $up_since, $total_users users, $cpu busy";

	"Connections: $total_c2s c2s, $total_s2sout s2sout, $total_s2sin s2sin, $total_component component";

	"Memory: $memory_lua lua, $memory_allocated process ($memory_used in use)";

	"Stanzas in: $message_in_per_second message/s, $presence_in_per_second presence/s, $iq_in_per_second iq/s";

	"Stanzas out: $message_out_per_second message/s, $presence_out_per_second presence/s, $iq_out_per_second iq/s";

};

function top:draw()

	self:draw_status();

	self:draw_column_titles();

	self:draw_conn_list();

	self.statuswin:refresh();

	self.listwin:refresh();

	--self.infowin:refresh()

	self.stdscr:move(#status_lines,0)

end

-- Width specified as cols or % of unused space, defaults to

-- title width if not specified

local conn_list_columns = {

	{ title = "ID", key = "id", width = "8" };

	{ title = "JID", key = "jid", width = "100%" };

	{ title = "STANZAS IN>", key = "total_stanzas_in", align = "right" };

	{ title = "MSG", key = "message_in", align = "right", width = "4" };

	{ title = "PRES", key = "presence_in", align = "right", width = "4" };

	{ title = "IQ", key = "iq_in", align = "right", width = "4" };

	{ title = "STANZAS OUT>", key = "total_stanzas_out", align = "right" };

	{ title = "MSG", key = "message_out", align = "right", width = "4" };

	{ title = "PRES", key = "presence_out", align = "right", width = "4" };

	{ title = "IQ", key = "iq_out", align = "right", width = "4" };

	{ title = "BYTES IN", key = "bytes_in", align = "right" };

	{ title = "BYTES OUT", key = "bytes_out", align = "right" };

};

function top:draw_status()

	for row, line in ipairs(status_lines) do

		self.statuswin:mvaddstr(row-1, 0, (line:gsub("%$([%w_]+)", self.data)));

		self.statuswin:clrtoeol();

	end

	-- Clear stanza counts

	for _, stanza_type in ipairs(stanza_names) do

		self.prosody[stanza_type.."_in_per_second"] = 0;

		self.prosody[stanza_type.."_out_per_second"] = 0;

	end

end

local function padright(s, width)

	return s..string.rep(" ", width-#s);

end

local function padleft(s, width)

	return string.rep(" ", width-#s)..s;

end

function top:resized()

	self:recalc_column_widths();

	--self.stdscr:clear();

	self:draw();

end

function top:recalc_column_widths()

	local widths = {};

	self.column_widths = widths;

	local total_width = curses.cols()-4;

	local free_width = total_width;

	for i = 1, #conn_list_columns do

		local width = conn_list_columns[i].width or "0";

		if not(type(width) == "string" and width:sub(-1) == "%") then

			width = math.max(tonumber(width), #conn_list_columns[i].title+1);

			widths[i] = width;

			free_width = free_width - width;

		end

	end

	for i = 1, #conn_list_columns do

		if not widths[i] then

			local pc_width = tonumber((conn_list_columns[i].width:gsub("%%$", "")));

			widths[i] = math.floor(free_width*(pc_width/100));

		end

	end

	return widths;

end

function top:draw_column_titles()

	local widths = self.column_widths;

	self.listwin:attron(curses.A_REVERSE);

	self.listwin:mvaddstr(0, 0, "  ");

	for i, column in ipairs(conn_list_columns) do

		self.listwin:addstr(padright(column.title, widths[i]));

	end

	self.listwin:addstr("  ");

	self.listwin:attroff(curses.A_REVERSE);

end

local function session_compare(session1, session2)

	local stats1, stats2 = session1.stats, session2.stats;

	return (stats1.total_stanzas_in + stats1.total_stanzas_out) >

		(stats2.total_stanzas_in + stats2.total_stanzas_out);

end

function top:draw_conn_list()

	local rows = curses.lines()-(#status_lines+2)-5;

	local cutoff_time = time() - sessions_idle_after;

	local widths = self.column_widths;

	local top_sessions = array.collect(it.values(self.active_sessions)):sort(session_compare);

	for index = 1, rows do

		local session = top_sessions[index];

		if session then

			if session.last_update < cutoff_time then

				self.active_sessions[session.id] = nil;

			else

				local row = {};

				for i, column in ipairs(conn_list_columns) do

					local width = widths[i];

					local v = tostring(session[column.key] or ""):sub(1, width);

					if #v < width then

						if column.align == "right" then

							v = padleft(v, width-1).." ";

						else

							v = padright(v, width);

						end

					end

					table.insert(row, v);

				end

				if session.updated then

					self.listwin:attron(curses.A_BOLD);

				end

				self.listwin:mvaddstr(index, 0, "  "..table.concat(row));

				if session.updated then

					session.updated = false;

					self.listwin:attroff(curses.A_BOLD);

				end

			end

		else

			-- FIXME: How to clear a line? It's 5am and I don't feel like reading docs.

			self.listwin:move(index, 0);

			self.listwin:clrtoeol();

		end

	end

end

function top:update_stat(name, value)

	self.prosody[name] = value;

end

function top:update_session(id, jid, stats)

	self.active_sessions[id] = stats;

	stats.id, stats.jid, stats.stats = id, jid, stats;

	stats.total_bytes = stats.bytes_in + stats.bytes_out;

	for _, stanza_type in ipairs(stanza_names) do

		self.prosody[stanza_type.."_in_per_second"] = (self.prosody[stanza_type.."_in_per_second"] or 0) + stats[stanza_type.."_in"];

		self.prosody[stanza_type.."_out_per_second"] = (self.prosody[stanza_type.."_out_per_second"] or 0) + stats[stanza_type.."_out"];

	end

	stats.total_stanzas_in = stats.message_in + stats.presence_in + stats.iq_in;

	stats.total_stanzas_out = stats.message_out + stats.presence_out + stats.iq_out;

	stats.last_update = time();

	stats.updated = true;

end

local function new(base)

	setmetatable(base, top);

	base.data = setmetatable({}, {

		__index = function (t, k)

			local stat = stats[k];

			if stat and stat.tostring then

				if type(stat.tostring) == "function" then

					return stat.tostring(base.prosody[k]);

				elseif type(stat.tostring) == "string" then

					local v = base.prosody[k];

					if v == nil then

						return "?";

					end

					return (stat.tostring):format(v);

				end

			end

			return base.prosody[k];

		end;

	});

	base.active_sessions = {};

	base.statuswin = curses.newwin(#status_lines, 0, 0, 0);

	base.promptwin = curses.newwin(1, 0, #status_lines, 0);

	base.promptwin:addstr("");

	base.promptwin:refresh();

	base.listwin = curses.newwin(curses.lines()-(#status_lines+2)-5, 0, #status_lines+1, 0);

	base.listwin:syncok();

	base.infowin = curses.newwin(5, 0, curses.lines()-5, 0);

	base.infowin:mvaddstr(1, 1, "Hello world");

	base.infowin:border(0,0,0,0);

	base.infowin:syncok();

	base.infowin:refresh();

	base:resized();

	return base;

end

return { new = new };