formspec.lua

--- Server Shops Formspec
--
--  @topic formspec


local ss = server_shop
local S = core.get_translator(ss.modname)

local transaction = dofile(ss.modpath .. "/transaction.lua")
local inventory = dofile(ss.modpath .. "/deposit.lua")


local fs_width = 14
local fs_height = 11
local btn_w = 1.75
local btn_y = 4.6


--- Retrieves shop name by ID *(deprecated)*.
--
--  @local
--  @function get_shop_name
--  @tparam string id String identifier of shop.
--  @tparam bool buyer
--  @treturn string Shop's name representation.
local get_shop_name = function(id, buyer)
	ss.log("warning", "get_shop_name: function is deprecated")

	if buyer ~= nil then
		ss.log("warning", "get_shop_name: \"buyer\" parameter is deprecated")
	end

	local shop = ss.get_shop(id)
	if shop then
		return shop.name
	end
end

--- Retrieves item name/id from shop list.
--
--  @local
--  @function get_shop_index
--  @param shop_id String identifier of shop.
--  @param idx Index of the item to retrieve.
--  @tparam bool buyer
--  @return String item identifier or `nil` if shop does not contain item.
local get_shop_index = function(shop_id, idx, buyer)
	if buyer ~= nil then
		ss.log("warning", "get_shop_index: \"buyer\" parameter is deprecated")
	end

	local shop = ss.get_shop(shop_id)
	if shop then
		local product = shop.products[idx]
		if product then
			return product[1]
		end
	end
end

--- Retrieves shop product list by ID.
--
--  @local
--  @function get_product_list
--  @param id String identifier of shop.
--  @tparam bool buyer
--  @return String of shop contents.
local get_product_list = function(id, buyer)
	if buyer ~= nil then
		ss.log("warning", "get_product_list: \"buyer\" parameter is deprecated")
	end

	local products = ""
	local shop = ss.get_shop(id)

	if shop and shop.products then
		for _, p in ipairs(shop.products) do
			local item = core.registered_items[p[1]]

			if not item then
				ss.log("warning", "Unknown item \"" .. p[1] .. "\" for shop ID \"" .. id .. "\"")
			else
				local item_name = item.short_description
				if not item_name then
					item_name = item.description
					if not item_name then
						item_name = p[1]
					end
				end

				local item_price = p[2]
				if not item_price then
					ss.log("warning", "Price not set for item \"" .. p[1] .. "\" for shop ID \"" .. id .. "\"")
				elseif products == "" then
					products = item_name .. " : " .. tostring(item_price)
				else
					products = products .. "," .. item_name .. " : " .. tostring(item_price)
				end

				if ss.currency_suffix then
					products = products .. " " .. ss.currency_suffix
				end
			end
		end
	end

	return products
end

--- Gets string formatted for use with form names.
--
--  @local
--  @function format_formname
--  @tparam bool buyer Denotes buyer or seller (can be `true`, `false`, or `nil`).
local format_formname = function(buyer)
	local t = {
		["buyer"] = true,
		["seller"] = false,
	}

	if type(buyer) == "string" then
		buyer = t[buyer]
	end

	if buyer == nil then
		return ss.modname..":unregistered"
	end

	if buyer then
		return ss.modname..":buy"
	end

	return ss.modname..":sell"
end


local quantities = {
	1,
	2,
	3,
	4,
	5,
	6,
	7,
	8,
	9,
	10,
	25,
	50,
	99,
}
quantities.get_idx = function(self, value)
	local idx = 1
	for _, v in ipairs(self) do
		if value == self[idx] then return idx end
		idx = idx + 1
	end

	return 1
end

--- Retrieves formspec layout.
--
--  @function server_shop.get_formspec
--  @tparam vector pos Shop node coordinates.
--  @tparam ObjectRef player Player to whom the formspec is shown.
--  @tparam[opt] MetaRef n_meta
--  @treturn string Formspec formatted string.
ss.get_formspec = function(id, player, n_meta)
		local pmeta = player:get_meta()
		local shop = ss.get_shop(id)

		local buyer, deposited, inv, inv_name
		if shop then
			buyer = shop.buyer == true
			deposited = transaction.get_deposit(id, player, buyer)

			-- store ID in player meta for retrieval during transactions
			pmeta:set_string(ss.modname .. ":id", id)

			-- make sure inventory has been created
			inv, inv_name = inventory.get(player:get_player_name(), buyer)

			-- check if player did not get items back
			if buyer and inv:is_empty("deposit") then
				if deposited.count and deposited.count > 0 then
					local stack = ItemStack(deposited.name)
					stack:set_count(deposited.count)
					inv:add_item("deposit", stack)
				end
			end
		end

		local margin_r = fs_width-(btn_w+0.2)
		local btn_refund = "button[0.2," .. tostring(btn_y) .. ";"
			.. tostring(btn_w) .. ",0.75;btn_refund;" .. S("Refund") .. "]"
		local btn_buy = "button[" .. tostring(margin_r) .. ","
			.. tostring(btn_y) .. ";" .. tostring(btn_w)
			.. ",0.75;btn_buy;" .. S("Buy") .. "]"
		local btn_sell = "button[" .. tostring(margin_r) .. ","
			.. tostring(btn_y) .. ";" .. tostring(btn_w)
			.. ",0.75;btn_sell;" .. S("Sell") .. "]"
		local btn_close = "button_exit[" .. tostring(margin_r) .. ",10;" .. tostring(btn_w)
			.. ",0.75;btn_close;" .. S("Close") .. "]"

		local formspec = "formspec_version[4]"
			.. "size[" .. tostring(fs_width) .. "," .. tostring(fs_height) .."]"

		if not ss.currency_is_registered() then
			return formspec.."label[0.2,1;"
				..S("Cannot use shops because there are no registered currencies.").."]"
					..btn_close
		end

		local shop_name = n_meta:get_string("label")
		if shop_name ~= "" then
			formspec = formspec .. "label[0.2,0.4;" .. shop_name .. "]"
		end

		if ss.is_shop_admin(player) then
			formspec = formspec
				.. "button[" .. margin_r .. ",0.2;" .. tostring(btn_w)
				.. ",0.75;btn_config;" .. S("Configure") .. "]"
		end

		local selected_idx = 1
		local quant_idx = 1
		if player then
			selected_idx = pmeta:get_int(ss.modname .. ":selected")
			quant_idx = quantities:get_idx(pmeta:get_int(ss.modname .. ":quant"))
		end
		if selected_idx < 1 then
			selected_idx = 1
		end

		-- get item name for displaying image
		local selected_item = nil
		if shop then
			-- make sure we're not out of range of the shop list
			if selected_idx > #shop.products then
				selected_idx = #shop.products
			end

			selected_item = shop.products[selected_idx]
			if selected_item then
				selected_item = selected_item[1]
			end
		end

		if not buyer then
			formspec = formspec .. "label[0.2,1;"
			if ss.currency_suffix and ss.currency_suffix ~= "" then
				formspec = formspec .. S("Deposited: @1 @2", tostring(deposited), ss.currency_suffix)
			else
				formspec = formspec .. S("Deposited: @1", tostring(deposited))
			end
			formspec = formspec .. "]"
		end

		if shop then -- don't allow deposits to unregistered stores
			formspec = formspec .. "list[detached:" .. inv_name .. ";deposit;0.2,1.5;1,1;0]"
		end

		formspec = formspec .. "textlist[2.15,1.5;9.75,3;products;"
			.. get_product_list(id) .. ";"
			.. tostring(selected_idx) .. ";false]"

		if selected_item and selected_item ~= "" then
			formspec = formspec
				.. "item_image[" .. tostring(fs_width-1.2) .. ",1.5;1,1;" .. selected_item .. "]"
		end

		if shop then
			if not buyer then
				formspec = formspec .. btn_refund
					.. "dropdown[" .. tostring(margin_r) .. ",3.77;" .. tostring(btn_w) .. ",0.75;quant;"
					.. table.concat(quantities, ",") .. ";" .. tostring(quant_idx) .. "]"
					.. btn_buy
			else
				formspec = formspec .. btn_sell
			end
		end

		return formspec	.. "list[current_player;main;2.15,5.5;8,4;0]" .. btn_close
end

local get_config_fs = function(pos)
	local margin_r = fs_width-(btn_w+0.2)
	local margin_b = fs_height-(0.75+0.2)

	local n_meta = core.get_meta(pos)

	local fs = "formspec_version[4]"
		.. "size[" .. tostring(fs_width) .. "," .. tostring(fs_height) .."]"
		.. "label[0.2,0.4;" .. S("Configure Shop") .. "]"
		.. "field[2.0,1.5;6,0.5;in_id;" .. S("ID") .. ";" .. n_meta:get_string("id") .. "]"
		.. "field_close_on_enter[in_id;false]"
		.. "field[2.0,2.5;6,0.5;in_label;" .. S("Label") .. ";" .. n_meta:get_string("label") .. "]"
		.. "field_close_on_enter[in_label;false]"
		.. "textarea[2.0,3.5;6,2.5;in_info;" .. S("Infotext") .. ";" .. n_meta:get_string("infotext") .. "]"
		.. "button[" .. margin_r-(btn_w+0.2) .. "," .. margin_b .. ";" .. btn_w
				.. ",0.75;btn_save;" .. S("Save") .. "]"
		.. "button[" .. margin_r .. "," .. margin_b .. ";" .. btn_w
				.. ",0.75;btn_cancel;" .. S("Cancel") .. "]"

	return fs
end

--- Displays formspec to player.
--
--  @function server_shop.show_formspec
--  @tparam vector pos Shop node coordinates.
--  @tparam ObjectRef player Player to whom the formspec is shown.
--  @tparam[opt] bool buyer (deprecated)
ss.show_formspec = function(pos, player, buyer)
	if buyer ~= nil then
		ss.log("warning", "show_formspec: \"buyer\" parameter is deprecated")
	end

	local n_meta = core.get_meta(pos)
	local id = n_meta:get_string("id")

	core.show_formspec(player:get_player_name(), format_formname(ss.shop_type(id)),
		ss.get_formspec(id, player, n_meta))
end


core.register_on_player_receive_fields(function(player, formname, fields)
	if formname == ss.modname .. ":config" then
		local pos = core.deserialize(player:get_meta():get_string(ss.modname .. ":pos"))
		if not pos then
			ss.log("error", "cannot retrieve shop position from player meta data")
			return false
		end

		if fields.btn_cancel then
			ss.show_formspec(pos, player)
		elseif fields.btn_save then
			if not ss.is_shop_admin(player) then
				ss.log("warning", "non-admin player " .. player:get_player_name()
					.. " attempted to configure shop at " .. core.pos_to_string(pos))
				return false
			end

			local n_meta = core.get_meta(pos)

			local shop_id = tostring(fields.in_id):trim()
			local shop_label = tostring(fields.in_label):trim()
			local shop_info = tostring(fields.in_info):trim()

			local attribs = {
				id = shop_id ~= "" and shop_id or nil,
				label = shop_label ~= "" and shop_label or nil,
				infotext = shop_info ~= "" and shop_info or nil,
			}

			for attrib, value in pairs(attribs) do
				n_meta:set_string(attrib, value)
			end

			ss.show_formspec(pos, player)
		end

		return false
	elseif string.find(formname, ss.modname..":") == 1 then
		local buyer = formname == format_formname(true)

		local p_name = player:get_player_name()
		local pmeta = player:get_meta()
		local pos = core.deserialize(pmeta:get_string(ss.modname .. ":pos"))
		if not pos then
			ss.log("error", "cannot retrieve shop position from player meta data")
			return false
		end

		local smeta = core.get_meta(pos)
		local id = smeta:get_string("id")

		local product_quant = 1
		if fields.quant then
			product_quant = tonumber(fields.quant)
		end

		if fields.quit then
			if server_shop.refund_on_close then
				if buyer then
					local inv = inventory.get(p_name, true)
					if not inv then return false end

					if not inv:is_empty("deposit") then
						local product = inv:get_stack("deposit", 1)
						transaction.give_product(player, product)
						inv:remove_item("deposit", product)
						-- clear deposit info from player meta
						transaction.clear_deposit(id, player, true)
					end
				else
					-- return money to player if formspec closed
					transaction.give_refund(id, player, false)
				end
			end

			if not buyer then
				-- reset selected amount
				pmeta:set_string(ss.modname .. ":quant", nil)
			end

			return false
		elseif fields.btn_config then
			core.show_formspec(p_name, ss.modname .. ":config",
				get_config_fs(pos))
			return false
		elseif fields.products then
			local idx = tonumber(fields.products:sub(5))
			if type(idx) == "number" then
				pmeta:set_int(ss.modname .. ":selected", idx)
			end
		elseif fields.btn_refund then
			transaction.give_refund(id, player, buyer)
		elseif fields.btn_buy then
			local idx = pmeta:get_int(ss.modname .. ":selected")
			local product = get_shop_index(id, idx)

			if not product then
				ss.log("warning", "Trying to buy undefined item from shop \""
					.. tostring(id) .. "\"")
				return false
			end

			local total = transaction.calculate_price(id, product, product_quant)

			local deposited = transaction.get_deposit(id, player)
			if total > deposited then
				core.chat_send_player(p_name, S("You haven't deposited enough money."))
				return false
			end

			product = ItemStack(product)
			product:set_count(product_quant)

			-- subtract total from deposited money
			transaction.set_deposit(id, player, deposited - total, buyer)

			-- execute transaction
			core.chat_send_player(p_name,
				S("You purchased @1 @2 for @3 @4.", product:get_count(),
					product:get_description(), total, ss.currency_suffix))

			transaction.give_product(player, product, product_quant)
		elseif fields.btn_sell then
			local inv, inv_name = inventory.get(p_name, true)
			if not inv then
				ss.log("error", "could not retrieve detached inventory: " .. inv_name)
				return false
			end

			if inv:is_empty("deposit") then return false end

			local product = inv:get_stack("deposit", 1)
			local total = transaction.calculate_product_value(product, id, true)
			if total <= 0 then return false end

			local refund, remain = transaction.calculate_refund(total)
			for _, istack in ipairs(refund) do
				transaction.give_product(player, istack)
			end

			core.chat_send_player(p_name,
				S("You sold @1 @2 for @3 @4.", product:get_count(),
					product:get_description(), total, ss.currency_suffix))

			inv:remove_item("deposit", product)
			-- clear deposit info from player meta
			transaction.clear_deposit(id, player, true)

			if remain > 0 then
				ss.log("warning", "buyer shop \"" .. id .. "\" failed to refund "
					.. remain .. " to player " .. p_name)
			elseif remain < 0 then
				ss.log("warning", "buyer shop \"" .. id .. "\" gave "
					.. remain .. " extra to player " .. p_name)
			end
		end

		-- refresh formspec view
		pmeta:set_int(ss.modname .. ":quant", product_quant)
		ss.show_formspec(pos, player)

		return false
	end
end)