local setmetatable = setmetatable;

local pairs, ipairs = pairs, ipairs;

local tostring, type = tostring, type;

local t_concat = table.concat;

local st = require "util.stanza";

module "dataforms"

local xmlns_forms = 'jabber:x:data';

local form_t = {};

local form_mt = { __index = form_t };

function new(layout)

	return setmetatable(layout, form_mt);

end

function form_t.form(layout, data)

	local form = st.stanza("x", { xmlns = xmlns_forms, type = "form" });

	if layout.title then

		form:tag("title"):text(layout.title):up();

	end

	if layout.instructions then

		form:tag("instructions"):text(layout.instructions):up();

	end

	for n, field in ipairs(layout) do

		local field_type = field.type or "text-single";

		-- Add field tag

		form:tag("field", { type = field_type, var = field.name, label = field.label });

		-- Add value, depending on type

		if field_type == "hidden" then

			if type(value) == "table" then

				-- Assume an XML snippet

				form:tag("value")

					:add_child(value)

					:up();

			elseif value then

				form:tag("value"):text(tostring(value)):up();

			end

		elseif field_type == "boolean" then

			form:tag("value"):text((value and "1") or "0"):up();

		elseif field_type == "fixed" then

		elseif field_type == "jid-multi" then

			for _, jid in ipairs(value) do

				form:tag("value"):text(jid):up();

			end

		elseif field_type == "jid-single" then

			form:tag("value"):text(value):up();

		elseif field_type == "text-single" or field_type == "text-private" then

			form:tag("value"):text(value):up();

		elseif field_type == "text-multi" then

			-- Split into multiple <value> tags, one for each line

			for line in value:gmatch("([^\r\n]+)\r?\n*") do

				form:tag("value"):text(line):up();

			end

		end

		if field.required then

			form:tag("required"):up();

		end

		-- Jump back up to list of fields

		form:up();

	end

	return form;

end

local field_readers = {};

function form_t.data(layout, stanza)

	local data = {};

	for field_tag in stanza:childtags() do

		local field_type = field_tag.attr.type;

		local reader = field_readers[field_type];

		if reader then

			data[field_tag.attr.var] = reader(field_tag);

		end

	end

	return data;

end

field_readers["text-single"] = 

	function (field_tag)

		local value = field_tag:child_with_name("value");

		if value then

			return value[1];

		end

	end

field_readers["text-private"] = 

	field_readers["text-single"];

field_readers["text-multi"] = 

	function (field_tag)

		local result = {};

		for value_tag in field_tag:childtags() do

			if value_tag.name == "value" then

				result[#result+1] = value_tag[1];

			end

		end

		return t_concat(result, "\n");

	end

field_readers["boolean"] = 

	function (field_tag)

		local value = field_tag:child_with_name("value");

		if value then

			if value[1] == "1" or value[1] == "true" then

				return true;

			else

				return false;

			end

		end		

	end

field_readers["hidden"] = 

	function (field_tag)

		local value = field_tag:child_with_name("value");

		if value then

			return value[1];

		end

	end

return _M;

--[=[

Layout:

{

	title = "MUC Configuration",

	instructions = [[Use this form to configure options for this MUC room.]],

	{ name = "FORM_TYPE", type = "hidden", required = true };

	{ name = "field-name", type = "field-type", required = false };

}

--]=]