-- Prosody IM

-- Copyright (C) 2008-2010 Matthew Wild

-- Copyright (C) 2008-2010 Waqas Hussain

--

-- This project is MIT/X11 licensed. Please see the

-- COPYING file in the source package for more information.

--

local setmetatable = setmetatable;

local ipairs = ipairs;

local type, next = type, next;

local tonumber = tonumber;

local t_concat = table.concat;

local st = require "util.stanza";

local jid_prep = require "util.jid".prep;

local _ENV = nil;

-- luacheck: std none

local xmlns_forms = 'jabber:x:data';

local xmlns_validate = 'http://jabber.org/protocol/xdata-validate';

local form_t = {};

local form_mt = { __index = form_t };

local function new(layout)

	return setmetatable(layout, form_mt);

end

function form_t.form(layout, data, formtype)

	if not formtype then formtype = "form" end

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

	if formtype == "cancel" then

		return form;

	end

	if formtype ~= "submit" then

		if layout.title then

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

		end

		if layout.instructions then

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

		end

	end

	for _, field in ipairs(layout) do

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

		-- Add field tag

		form:tag("field", { type = field_type, var = field.var or field.name, label = formtype ~= "submit" and field.label or nil });

		if formtype ~= "submit" then

			if field.desc then

				form:text_tag("desc", field.desc);

			end

		end

		if formtype == "form" and field.datatype then

			form:tag("validate", { xmlns = xmlns_validate, datatype = field.datatype });

			-- <basic/> assumed

			form:up();

		end

		local value = field.value;

		local options = field.options;

		if data and data[field.name] ~= nil then

			value = data[field.name];

			if formtype == "form" and type(value) == "table"

				and (field_type == "list-single" or field_type == "list-multi") then

				-- Allow passing dynamically generated options as values

				options, value = value, nil;

			end

		end

		if formtype == "form" and options then

			local defaults = {};

			for _, val in ipairs(options) do

				if type(val) == "table" then

					form:tag("option", { label = val.label }):tag("value"):text(val.value):up():up();

					if val.default then

						defaults[#defaults+1] = val.value;

					end

				else

					form:tag("option", { label= val }):tag("value"):text(val):up():up();

				end

			end

			if not value then

				if field_type == "list-single" then

					value = defaults[1];

				elseif field_type == "list-multi" then

					value = defaults;

				end

			end

		end

		if value ~= nil then

			if type(value) == "number" then

				-- TODO validate that this is ok somehow, eg check field.datatype

				value = ("%g"):format(value);

			end

			-- 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();

				else

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

				end

			elseif field_type == "boolean" then

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

			elseif field_type == "fixed" then

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

			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

			elseif field_type == "list-single" then

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

			elseif field_type == "list-multi" then

				for _, val in ipairs(value) do

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

				end

			end

		end

		local media = field.media;

		if media then

			for _, val in ipairs(media) do

				form:tag("uri", { type = val.type }):text(val.uri):up()

			end

			form:up();

		end

		if formtype == "form" and field.required then

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

		end

		-- Jump back up to list of fields

		form:up();

	end

	return form;

end

local field_readers = {};

local data_validators = {};

function form_t.data(layout, stanza, current)

	local data = {};

	local errors = {};

	local present = {};

	for _, field in ipairs(layout) do

		local tag;

		for field_tag in stanza:childtags("field") do

			if (field.var or field.name) == field_tag.attr.var then

				tag = field_tag;

				break;

			end

		end

		if not tag then

			if current and current[field.name] ~= nil then

				data[field.name] = current[field.name];

			elseif field.required then

				errors[field.name] = "Required value missing";

			end

		elseif field.name then

			present[field.name] = true;

			local reader = field_readers[field.type];

			if reader then

				local value, err = reader(tag, field.required);

				local validator = field.datatype and data_validators[field.datatype];

				if value ~= nil and validator then

					local valid, ret = validator(value, field);

					if valid then

						value = ret;

					else

						value, err = nil, ret or ("Invalid value for data of type " .. field.datatype);

					end

				end

				data[field.name], errors[field.name] = value, err;

			end

		end

	end

	if next(errors) then

		return data, errors, present;

	end

	return data, nil, present;

end

local function simple_text(field_tag, required)

	local data = field_tag:get_child_text("value");

	-- XEP-0004 does not say if an empty string is acceptable for a required value

	-- so we will follow HTML5 which says that empty string means missing

	if required and (data == nil or data == "") then

		return nil, "Required value missing";

	end

	return data; -- Return whatever get_child_text returned, even if empty string

end

field_readers["text-single"] = simple_text;

field_readers["text-private"] = simple_text;

field_readers["jid-single"] =

	function (field_tag, required)

		local raw_data, err = simple_text(field_tag, required);

		if not raw_data then return raw_data, err; end

		local data = jid_prep(raw_data);

		if not data then

			return nil, "Invalid JID: " .. raw_data;

		end

		return data;

	end

field_readers["jid-multi"] =

	function (field_tag, required)

		local result = {};

		local err = {};

		for value_tag in field_tag:childtags("value") do

			local raw_value = value_tag:get_text();

			local value = jid_prep(raw_value);

			result[#result+1] = value;

			if raw_value and not value then

				err[#err+1] = ("Invalid JID: " .. raw_value);

			end

		end

		if #result > 0 then

			return result, (#err > 0 and t_concat(err, "\n") or nil);

		elseif required then

			return nil, "Required value missing";

		end

	end

field_readers["list-multi"] =

	function (field_tag, required)

		local result = {};

		for value in field_tag:childtags("value") do

			result[#result+1] = value:get_text();

		end

		if #result > 0 then

			return result;

		elseif required then

			return nil, "Required value missing";

		end

	end

field_readers["text-multi"] =

	function (field_tag, required)

		local data, err = field_readers["list-multi"](field_tag, required);

		if data then

			data = t_concat(data, "\n");

		end

		return data, err;

	end

field_readers["list-single"] = simple_text;

local boolean_values = {

	["1"] = true, ["true"] = true,

	["0"] = false, ["false"] = false,

};

field_readers["boolean"] =

	function (field_tag, required)

		local raw_value, err = simple_text(field_tag, required);

		if not raw_value then return raw_value, err; end

		local value = boolean_values[raw_value];

		if value == nil then

			return nil, "Invalid boolean representation:" .. raw_value;

		end

		return value;

	end

field_readers["hidden"] =

	function (field_tag)

		return field_tag:get_child_text("value");

	end

data_validators["xs:integer"] =

	function (data)

		local n = tonumber(data);

		if not n then

			return false, "not a number";

		elseif n % 1 ~= 0 then

			return false, "not an integer";

		end

		return true, n;

	end

local function get_form_type(form)

	if not st.is_stanza(form) then

		return nil, "not a stanza object";

	elseif form.attr.xmlns ~= "jabber:x:data" or form.name ~= "x" then

		return nil, "not a dataform element";

	end

	for field in form:childtags("field") do

		if field.attr.var == "FORM_TYPE" then

			return field:get_child_text("value");

		end

	end

	return "";

end

return {

	new = new;

	get_type = get_form_type;

};

--[=[

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 };

}

--]=]