---
--vendor
--Copyright (C) 2012 Bad_Command
--Rewrited by Andrej
--
--This library is free software; you can redistribute it and/or
--modify it under the terms of the GNU Lesser General Public
--License as published by the Free Software Foundation; either
--version 2.1 of the License, or (at your option) any later version.
--
--This program is distributed in the hope that it will be useful,
--but WITHOUT ANY WARRANTY; without even the implied warranty of
--MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
--GNU General Public License for more details.
--
--You should have received a copy of the GNU Lesser General Public
--License along with this library; if not, write to the Free Software
--Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
---

-- TODO: Improve mod compability
local slots_max = 31

local registered_chests = {}
local cost_stack_max = minetest.registered_items[easyvend.currency].stack_max
local maxcost = cost_stack_max * slots_max

local joketimer_start = 3

-- Allow for other mods to register custom chests
easyvend.register_chest = function(node_name, inv_list, meta_owner)
	registered_chests[node_name] = { inv_list = inv_list, meta_owner = meta_owner }
end

-- Partly a wrapper around contains_item, but does special treatment if the item
-- is a tool. Basically checks whether the items exist in the supplied inventory
-- list. If check_wear is true, only counts items without wear.
easyvend.check_and_get_items = function(inventory, listname, itemtable, check_wear)
	local itemstring = itemtable.name
	local minimum = itemtable.count
	if check_wear == nil then check_wear = false end
	local get_items = {}
	-- Tool workaround
	if minetest.registered_tools[itemstring] ~= nil then
		local count = 0
		for i=1,inventory:get_size(listname) do
			local stack = inventory:get_stack(listname, i)
			if stack:get_name() == itemstring then
				if not check_wear or stack:get_wear() == 0 then
					count = count + 1
					table.insert(get_items, {id=i, item=stack})
					if count >= minimum then
						return true, get_items
					end
				end
			end
		end
		return false
	else
		-- Normal Minetest check
		return inventory:contains_item(listname, ItemStack(itemtable))
	end
end


if minetest.get_modpath("default") ~= nil then
	easyvend.register_chest("default:chest_locked", "main", "owner")
end

easyvend.free_slots= function(inv, listname)
	local size = inv:get_size(listname)
	local free = 0
	for i=1,size do
		local stack = inv:get_stack(listname, i)
		if stack:is_empty() then
			free = free + 1
		end
	end
	return free
end

easyvend.buysell = function(nodename)
	local buysell = nil
	if ( nodename == "easyvend:depositor" or nodename == "easyvend:depositor_on" ) then
		buysell = "buy"
	elseif ( nodename == "easyvend:vendor" or nodename == "easyvend:vendor_on" ) then
		buysell = "sell"
	end
	return buysell
end

easyvend.is_active = function(nodename)
	if ( nodename == "easyvend:depositor_on" or nodename == "easyvend:vendor_on" ) then
		return true
	elseif ( nodename == "easyvend:depositor" or nodename == "easyvend:vendor" ) then
		return false
	else
		return nil
	end
end

easyvend.set_formspec = function(pos, player)
	local meta = minetest.get_meta(pos)
	local node = minetest.get_node(pos)

	local description = minetest.registered_nodes[node.name].description;
	local number = meta:get_int("number")
	local cost = meta:get_int("cost")
	local itemname = meta:get_string("itemname")
        local bg = ""
	local configmode = meta:get_int("configmode") == 1
        if minetest.get_modpath("default") then
            bg = default.gui_bg .. default.gui_bg_img .. default.gui_slots
        end

        local numbertext, costtext, buysellbuttontext
	local itemcounttooltip = "Item count (append “s” to multiply with maximum stack size)"
        local buysell = easyvend.buysell(node.name)
        if buysell == "sell" then
		numbertext = "Offered item"
		costtext = "Price"
		buysellbuttontext = "Buy"
        elseif buysell == "buy" then
		numbertext = "Requested item"
		costtext = "Payment"
		buysellbuttontext = "Sell"
        else
		return
	end
	local status = meta:get_string("status")
	if status == "" then status = "Unknown." end
	local message = meta:get_string("message")
	if message == "" then message = "No message." end
	local status_image
	if node.name == "easyvend:vendor_on" or node.name == "easyvend:depositor_on" then
		status_image = "easyvend_status_on.png"
	else
		status_image = "easyvend_status_off.png"
	end

	-- TODO: Expose number of items in stock

	local formspec = "size[8,7.3;]"
        .. bg
	.."label[3,-0.2;" .. minetest.formspec_escape(description) .. "]"

	.."image[7.5,0.2;0.5,1;" .. status_image .. "]"
	.."textarea[2.8,0.2;5.1,2;;Status: " .. minetest.formspec_escape(status) .. ";]"
	.."textarea[2.8,1.3;5.6,2;;Message: " .. minetest.formspec_escape(message) .. ";]"

		.."label[0,-0.15;"..numbertext.."]"
		.."label[0,1.2;"..costtext.."]"
        .."list[current_player;main;0,3.5;8,4;]"

	if configmode then
		local wear = "false"
		if meta:get_int("wear") == 1 then wear = "true" end
		formspec = formspec
                .."item_image_button[0,1.65;1,1;"..easyvend.currency..";easyvend.currency_image;]"
                .."list[current_name;item;0,0.35;1,1;]"
                .."listring[current_player;main]"
                .."listring[current_name;item]"
		.."field[1.3,0.65;1.5,1;number;;" .. number .. "]"
		.."tooltip[number;"..itemcounttooltip.."]"
		.."field[1.3,1.95;1.5,1;cost;;" .. cost .. "]"
		.."tooltip[cost;"..itemcounttooltip.."]"
		.."button[6,2.8;2,0.5;save;Confirm]"
		.."tooltip[save;Confirm configuration and activate machine (only for owner)]"
		local weartext, weartooltip
		if buysell == "buy" then
			weartext = "Accept worn tools"
			weartooltip = "If disabled, only tools in perfect condition will be bought from sellers (only settable by owner)"
		else
			weartext = "Sell worn tools"
			weartooltip = "If disabled, only tools in perfect condition will be sold (only settable by owner)"
		end
		if minetest.registered_tools[itemname] ~= nil then
			formspec = formspec .."checkbox[2,2.4;wear;"..minetest.formspec_escape(weartext)..";"..wear.."]"
			.."tooltip[wear;"..minetest.formspec_escape(weartooltip).."]"
		end
	else
		formspec = formspec
                .."item_image_button[0,1.65;1,1;"..easyvend.currency..";easyvend.currency_image;]"
                .."item_image_button[0,0.35;1,1;"..itemname..";item_image;]"
		.."label[1,1.85;×" .. cost .. "]"
		.."label[1,0.55;×" .. number .. "]"
		.."button[6,2.8;2,0.5;config;Configure]"
		if buysell == "sell" then
			formspec = formspec .. "tooltip[config;Configure offered items and price (only for owner)]"
		else
			formspec = formspec .. "tooltip[config;Configure requested items and payment (only for owner)]"
		end
		formspec = formspec .."button[0,2.8;2,0.5;buysell;"..buysellbuttontext.."]"
		if minetest.registered_tools[itemname] ~= nil then
			local weartext
			if meta:get_int("wear") == 0 then
				if buysell == "buy" then
					weartext = "Only intact tools are bought."
				else
					weartext = "Only intact tools are sold."
				end
			elseif buysell == "sell" then
				weartext = "Warning: Might sell worn tools."
			end
			if weartext ~= nil then
				formspec = formspec .."textarea[2.3,2.6;3,1;;"..minetest.formspec_escape(weartext)..";]"
			end
		end
	end

	meta:set_string("formspec", formspec)
end

easyvend.machine_disable = function(pos, node, playername)
	if node.name == "easyvend:vendor_on" then
                easyvend.sound_disable(pos)
		minetest.swap_node(pos, {name="easyvend:vendor", param2 = node.param2})
		return true
	elseif node.name == "easyvend:depositor_on" then
                easyvend.sound_disable(pos)
		minetest.swap_node(pos, {name="easyvend:depositor", param2 = node.param2})
		return true
	else
		if playername ~= nil then
			easyvend.sound_error(playername)
		end
		return false
	end
end

easyvend.machine_enable = function(pos, node)
        if node.name == "easyvend:vendor" then
                easyvend.sound_setup(pos)
		minetest.swap_node(pos, {name="easyvend:vendor_on", param2 = node.param2})
		return true
	elseif node.name == "easyvend:depositor" then
                easyvend.sound_setup(pos)
		minetest.swap_node(pos, {name="easyvend:depositor_on", param2 = node.param2})
		return true
	else
		return false
	end
end

easyvend.machine_check = function(pos, node)
	local active = true
	local status = "Ready."

	local chest = minetest.get_node({x=pos.x,y=pos.y-1,z=pos.z})
	local meta = minetest.get_meta(pos)
	local number = meta:get_int("number")
	local cost = meta:get_int("cost")
	local inv = meta:get_inventory()
	local itemstack = inv:get_stack("item",1)
	local itemname=meta:get_string("itemname")
	local machine_owner = meta:get_string("owner")
	local check_wear = meta:get_int("wear") == 0
	local chestdef = registered_chests[chest.name]
	local chest_meta, chest_inv

	if chestdef then
		chest_meta = minetest.get_meta({x=pos.x,y=pos.y-1,z=pos.z})
		chest_inv = chest_meta:get_inventory()

		if ( chest_meta:get_string(chestdef.meta_owner) == machine_owner and chest_inv ~= nil ) then
			local buysell = easyvend.buysell(node.name)

			local checkstack, checkitem
			if buysell == "buy" then
				checkitem = easyvend.currency
			else
				checkitem = itemname
			end
			local stock = 0
			-- Count stock
			-- FIXME: Ignore tools with bad wear level
			for i=1,chest_inv:get_size(chestdef.inv_list) do
				checkstack = chest_inv:get_stack(chestdef.inv_list, i)
				if checkstack:get_name() == checkitem then
					stock = stock + checkstack:get_count()
				end
			end
			meta:set_int("stock", stock)

			if not itemstack:is_empty() then
				local number_stack_max = itemstack:get_stack_max()
				if number >= 1 and number < number_stack_max and cost >= 1 and cost <= cost_stack_max then
					local stack = {name=itemname, count=number, wear=0, metadata=""}
					local price = {name=easyvend.currency, count=cost, wear=0, metadata=""}

					local chest_has, chest_free

					local coststacks = math.modf(cost / cost_stack_max)
					local costremainder = math.fmod(cost, cost_stack_max)
					local numberstacks = math.modf(number / number_stack_max)
					local numberremainder = math.fmod(number, number_stack_max)
					local numberfree = numberstacks
					local costfree = coststacks
					if numberremainder > 0 then numberfree = numberfree + 1 end
					if costremainder > 0 then costfree = costfree + 1 end

					if buysell == "sell" then
						chest_has = easyvend.check_and_get_items(chest_inv, chestdef.inv_list, stack, check_wear)
						chest_free = chest_inv:room_for_item(chestdef.inv_list, price)
				                if chest_has and chest_free then
							if cost <= cost_stack_max and number <= number_stack_max then
								active = true
							elseif easyvend.free_slots(chest_inv, chestdef.inv_list) < costfree then
								active = false
								status = "No room in the machine’s storage!"
							end
						elseif not chest_has then
							active = false
							status = "The vending machine has insufficient materials!"
						elseif not chest_free then
							active = false
							status = "No room in the machine’s storage!"
						end
					elseif buysell == "buy" then
						chest_has = easyvend.check_and_get_items(chest_inv, chestdef.inv_list, price, check_wear)
						chest_free = chest_inv:room_for_item(chestdef.inv_list, stack)
				                if chest_has and chest_free then
							if cost <= cost_stack_max and number <= number_stack_max then
								active = true
							elseif easyvend.free_slots(chest_inv, chestdef.inv_list) < numberfree then
								active = false
								status = "No room in the machine’s storage!"
							end
						elseif not chest_has then
							active = false
							status = "The depositing machine is out of money!"
						elseif not chest_free then
							active = false
							status = "No room in the machine’s storage!"
						end
					end
				else
					active = false
					if buysell == "sell" then
						status = "Invalid item count or price."
					else
						status = "Invalid item count or payment."
					end
				end
			else
				active = false
				status = "Awaiting configuration by owner."
			end
		else
			meta:set_int("stock", 0)
			active = false
                        status = "Storage can’t be accessed because it is owned by a different person!"
		end
	else
		meta:set_int("stock", 0)
		active = false
                status = "No storage; machine needs a locked chest below it."
        end
	if meta:get_int("configmode") == 1 then
		active = false
		status = "Awaiting configuration by owner."
	end

        if itemname == easyvend.currency and number == cost and active then
            local jt = meta:get_int("joketimer")
            if jt > 0 then
                jt = jt - 1
            end
            if jt == 0 then
                if buysell == "sell" then
                    meta:set_string("message", "Item bought.")
                else
                    meta:set_string("message", "Item sold.")
                end
                jt = -1
            end
            meta:set_int("joketimer", jt)
        end
	meta:set_string("status", status)

	meta:set_string("infotext", easyvend.make_infotext(node.name, machine_owner, cost, number, itemname))
	itemname=itemstack:get_name()
	meta:set_string("itemname", itemname)

	local change
	if node.name == "easyvend:vendor" or node.name == "easyvend:depositor" then
		if active then change = easyvend.machine_enable(pos, node) end
	elseif node.name == "easyvend:vendor_on" or node.name == "easyvend:depositor_on" then
		if not active then change = easyvend.machine_disable(pos, node) end
	end
        easyvend.set_formspec(pos)
	return change
end

easyvend.on_receive_fields_config = function(pos, formname, fields, sender)
    local node = minetest.get_node(pos)
	local meta = minetest.get_meta(pos)
    local inv_self = meta:get_inventory()
    local itemstack = inv_self:get_stack("item",1)
    local buysell = easyvend.buysell(node.name)
 
    if fields.config then
        meta:set_int("configmode", 1)
	local was_active = easyvend.is_active(node.name)
	if was_active then
		meta:set_string("message", "Configuration mode activated; machine disabled.")
	else
		meta:set_string("message", "Configuration mode activated.")
	end
	easyvend.machine_check(pos, node)
	return
    end

    if not fields.save then
        return
    end

	local number = fields.number
	local cost = fields.cost

    --[[ Convenience function:
    When appending “s” or “S” to the number, it is multiplied
    by the maximum stack size.
    TODO: Expose this in user documentation ]]
    local number_stack_max = itemstack:get_stack_max()
    local ss = string.sub(number, #number, #number)
    if ss == "s" or ss == "S" then
        local n = tonumber(string.sub(number, 1, #number-1))
        if string.len(number) == 1 then n = 1 end
	if n ~= nil then
		number = n * number_stack_max
	end
    end
    ss = string.sub(cost, #cost, #cost)
    if ss == "s" or ss == "S" then
        local n = tonumber(string.sub(cost, 1, #cost-1))
        if string.len(cost) == 1 then n = 1 end
	if n ~= nil then
		cost = n * cost_stack_max
	end
    end
    number = tonumber(number)
    cost = tonumber(cost)

    local itemname=""

    local oldnumber = meta:get_int("number")
    local oldcost = meta:get_int("cost")
    local maxnumber = number_stack_max * slots_max
	
        if ( itemstack == nil or itemstack:is_empty() ) then
                meta:set_string("status", "Awaiting configuration by owner.")
		meta:set_string("message", "No item specified.")
                easyvend.sound_error(sender:get_player_name())
                easyvend.set_formspec(pos, sender)
                return
	elseif ( number == nil or number < 1 or number > maxnumber ) then
                if maxnumber > 1 then
			meta:set_string("message", string.format("Invalid item count; must be between 1 and %d!", maxnumber))
                else
			meta:set_string("message", "Invalid item count; must be exactly 1!")
                end
                meta:set_int("number", oldnumber)
                easyvend.sound_error(sender:get_player_name())
                easyvend.set_formspec(pos, sender)
                return
	elseif ( cost == nil or cost < 1 or cost > maxcost ) then
                if maxcost > 1 then
			meta:set_string("message", string.format("Invalid cost; must be between 1 and %d!", maxcost))
                else
			meta:set_string("message", "Invalid cost; must be exactly 1!")
                end
                meta:set_int("cost", oldcost)
                easyvend.sound_error(sender:get_player_name())
                easyvend.set_formspec(pos, sender)
                return
        end
        meta:set_int("number", number)
        meta:set_int("cost", cost)
        itemname=itemstack:get_name()
	meta:set_string("itemname", itemname)
        meta:set_int("configmode", 0)

        if itemname == easyvend.currency and number == cost and cost <= cost_stack_max then
	    meta:set_string("message", "Configuration successful. I am feeling funny.")
	    meta:set_int("joketimer", joketimer_start)
	    meta:set_int("joke_id", easyvend.assign_joke(buysell))
        else
	    meta:set_string("message", "Configuration successful.")
        end

        local change = easyvend.machine_check(pos, node)

	if not change then
		if (node.name == "easyvend:vendor_on" or node.name == "easyvend:depositor_on") then
			easyvend.sound_setup(pos)
		else
			easyvend.sound_disable(pos)
		end
	end
end

easyvend.make_infotext = function(nodename, owner, cost, number, itemstring)
	local d = ""
	if itemstring == nil or itemstring == "" or number == 0 or cost == 0 then
		if easyvend.buysell(nodename) == "sell" then
			d = string.format("Inactive vending machine (owned by %s)", owner)
		else
			d = string.format("Inactive depositing machine (owned by %s)", owner)
		end
		return d
	end
	local iname = minetest.registered_items[itemstring].description
	if iname == nil then iname = itemstring end
	local printitem, printcost
	if number == 1 then
		printitem = iname
	else
		printitem = string.format("%d×%s", number, iname)
	end
	if cost == 1 then
		printcost = easyvend.currency_desc
	else
		printcost = string.format("%d×%s", cost, easyvend.currency_desc)
	end
	if nodename == "easyvend:vendor_on" then
		d = string.format("Vending machine (owned by %s)\nSelling: %s\nPrice: %s", owner, printitem, printcost)
	elseif nodename == "easyvend:vendor" then
		d = string.format("Inactive vending machine (owned by %s)\nSelling: %s\nPrice: %s", owner, printitem, printcost)
	elseif nodename == "easyvend:depositor_on" then
		d = string.format("Depositing machine (owned by %s)\nBuying: %s\nPayment: %s", owner, printitem, printcost)
	elseif nodename == "easyvend:depositor" then
		d = string.format("Inactive depositing machine (owned by %s)\nBuying: %s\nPayment: %s", owner, printitem, printcost)
	end
	return d
end

easyvend.on_receive_fields_buysell = function(pos, formname, fields, sender)
    local sendername = sender:get_player_name()
    local meta = minetest.get_meta(pos)

    if not fields.buysell then
        return
    end

	local node = minetest.get_node(pos)
    local number = meta:get_int("number")
    local cost = meta:get_int("cost")
    local itemname=meta:get_string("itemname")
    local item=meta:get_inventory():get_stack("item", 1)
    local check_wear = meta:get_int("wear") == 0 and minetest.registered_tools[itemname] ~= nil

    local buysell = easyvend.buysell(node.name)
	
        local number_stack_max = item:get_stack_max()
        local maxnumber = number_stack_max * slots_max
	if ( number == nil or number < 1 or number > maxnumber ) or
	( cost == nil or cost < 1 or cost > maxcost ) or
	( itemname == nil or itemname=="") then
		meta:set_string("status", "Invalid item count or price!")
	        easyvend.machine_disable(pos, node, sendername)
		return
	end

    
    local chest = minetest.get_node({x=pos.x,y=pos.y-1,z=pos.z})
    local chestdef = registered_chests[chest.name]
    if chestdef and sender and sender:is_player() then
        local chest_meta = minetest.get_meta({x=pos.x,y=pos.y-1,z=pos.z})
        local chest_inv = chest_meta:get_inventory()
        local player_inv = sender:get_inventory()
        if ( chest_meta:get_string(chestdef.meta_owner) == meta:get_string("owner") and chest_inv ~= nil and player_inv ~= nil ) then
            
            local stack = {name=itemname, count=number, wear=0, metadata=""} 
            local price = {name=easyvend.currency, count=cost, wear=0, metadata=""}
            local chest_has, player_has, chest_free, player_free, chest_out, player_out
            local msg = ""
            if buysell == "sell" then
                chest_has, chest_out = easyvend.check_and_get_items(chest_inv, "main", stack, check_wear)
                player_has, player_out = easyvend.check_and_get_items(player_inv, "main", price, check_wear)
                chest_free = chest_inv:room_for_item("main", price)
                player_free = player_inv:room_for_item("main", stack)
                if chest_has and player_has and chest_free and player_free then
                   if cost <= cost_stack_max and number <= number_stack_max then
                       easyvend.machine_enable(pos, node)
                       player_inv:remove_item("main", price)
                       if check_wear then
                           chest_inv:set_stack("main", chest_out[1].id, "")
                           player_inv:add_item("main", chest_out[1].item)
                       else
                           stack = chest_inv:remove_item("main", stack)
                           player_inv:add_item("main", stack)
                       end
                       chest_inv:add_item("main", price)
                       if itemname == easyvend.currency and number == cost and cost <= cost_stack_max then
                           meta:set_string("message", easyvend.get_joke(buysell, meta:get_int("joke_id")))
                           meta:set_int("joketimer", joketimer_start)
                       else
                           meta:set_string("message", "Item bought.")
                       end
                       easyvend.sound_vend(pos)
                       easyvend.machine_check(pos, node)
                   else
                       -- Large item counts (multiple stacks)
                       local coststacks = math.modf(cost / cost_stack_max)
                       local costremainder = math.fmod(cost, cost_stack_max)
                       local numberstacks = math.modf(number / number_stack_max)
                       local numberremainder = math.fmod(number, number_stack_max)
                       local numberfree = numberstacks
                       local costfree = coststacks
                       if numberremainder > 0 then numberfree = numberfree + 1 end
                       if costremainder > 0 then costfree = costfree + 1 end
                       if easyvend.free_slots(player_inv, "main") < numberfree then
                           if numberfree > 1 then
                               msg = string.format("No room in your inventory (%d empty slots required)!", numberfree)
                           else
                               msg = "No room in your inventory!"
                           end
                           meta:set_string("message", msg)
                       elseif easyvend.free_slots(chest_inv, "main") < costfree then
                           meta:set_string("status", "No room in the machine’s storage!")
	                   easyvend.machine_disable(pos, node, sendername)
                       else
                           -- Remember items for transfer
                           local cheststacks = {}
                           easyvend.machine_enable(pos, node)
                           for i=1, coststacks do
                               price.count = cost_stack_max
                               player_inv:remove_item("main", price)
                           end
                           if costremainder > 0 then
                               price.count = costremainder
                               player_inv:remove_item("main", price)
                           end
                           if check_wear then
                               for o=1,#chest_out do
                                   chest_inv:set_stack("main", chest_out[o].id, "")
                               end
                           else
                               for i=1, numberstacks do
                                   stack.count = number_stack_max
                                   table.insert(cheststacks, chest_inv:remove_item("main", stack))
                               end
                           end
                           if numberremainder > 0 then
                               stack.count = numberremainder
                               table.insert(cheststacks, chest_inv:remove_item("main", stack))
                           end
                           for i=1, coststacks do
                               price.count = cost_stack_max
                               chest_inv:add_item("main", price)
                           end
                           if costremainder > 0 then
                               price.count = costremainder
                               chest_inv:add_item("main", price)
                           end
                           if check_wear then
                               for o=1,#chest_out do
                                   player_inv:add_item("main", chest_out[o].item)
                               end
                           else
                               for i=1,#cheststacks do
                                   player_inv:add_item("main", cheststacks[i])
                               end
                           end
                           meta:set_string("message", "Item bought.")
                           easyvend.sound_vend(pos)
                           easyvend.machine_check(pos, node)
                       end
                   end
                elseif chest_has and player_has then
                    if not player_free then
                        msg = "No room in your inventory!"
                        meta:set_string("message", msg)
                        easyvend.sound_error(sendername)
                    elseif not chest_free then
                        msg = "No room in the machine’s storage!"
                        meta:set_string("status", msg)
	                easyvend.machine_disable(pos, node, sendername)
                    end
                else
                    if not chest_has then
                        msg = "The vending machine has insufficient materials!"
                        meta:set_string("status", msg)
	                easyvend.machine_disable(pos, node, sendername)
                    elseif not player_has then
                        msg = "You can’t afford this item!"
                        meta:set_string("message", msg)
                        easyvend.sound_error(sendername)
                    end
                end
            else
                chest_has, chest_out = easyvend.check_and_get_items(chest_inv, "main", price, check_wear)
                player_has, player_out = easyvend.check_and_get_items(player_inv, "main", stack, check_wear)
                chest_free = chest_inv:room_for_item("main", stack)
                player_free = player_inv:room_for_item("main", price)
                if chest_has and player_has and chest_free and player_free then
                   if cost <= cost_stack_max and number <= number_stack_max then
                       easyvend.machine_enable(pos, node)
                       if check_wear then
                           player_inv:set_stack("main", player_out[1].id, "")
                           chest_inv:add_item("main", player_out[1].item)
                       else
                           stack = player_inv:remove_item("main", stack)
                           chest_inv:add_item("main", stack)
                       end
                       chest_inv:remove_item("main", price)
                       player_inv:add_item("main", price)
                       meta:set_string("status", "Ready.")
                       if itemname == easyvend.currency and number == cost and cost <= cost_stack_max then
                           meta:set_string("message", easyvend.get_joke(buysell, meta:get_int("joke_id")))
                           meta:set_int("joketimer", joketimer_start)
                       else
                           meta:set_string("message", "Item sold.")
                       end
                       easyvend.sound_deposit(pos)
                       easyvend.machine_check(pos, node)
                   else
                       -- Large item counts (multiple stacks)
                       local coststacks = math.modf(cost / cost_stack_max)
                       local costremainder = math.fmod(cost, cost_stack_max)
                       local numberstacks = math.modf(number / number_stack_max)
                       local numberremainder = math.fmod(number, number_stack_max)
                       local numberfree = numberstacks
                       local costfree = coststacks
                       if numberremainder > 0 then numberfree = numberfree + 1 end
                       if costremainder > 0 then costfree = costfree + 1 end
                       if easyvend.free_slots(player_inv, "main") < costfree then
                           if costfree > 1 then
                               msg = string.format("No room in your inventory (%d empty slots required)!", costfree)
                           else
                               msg = "No room in your inventory!"
                           end
                           meta:set_string("message", msg)
                           easyvend.sound_error(sendername)
                       elseif easyvend.free_slots(chest_inv, "main") < numberfree then
	                   easyvend.machine_disable(pos, node, sendername)
                       else
                           easyvend.machine_enable(pos, node)
                           -- Remember removed items for transfer
                           local playerstacks = {}
                           for i=1, coststacks do
                               price.count = cost_stack_max
                               chest_inv:remove_item("main", price)
                           end
                           if costremainder > 0 then
                               price.count = costremainder
                               chest_inv:remove_item("main", price)
                           end
                           if check_wear then
                               for o=1,#player_out do
                                   player_inv:set_stack("main", player_out[o].id, "")
                               end
                           else
                               for i=1, numberstacks do
                                   stack.count = number_stack_max
                                   table.insert(playerstacks, player_inv:remove_item("main", stack))
                               end
                           end
                           if numberremainder > 0 then
                               stack.count = numberremainder
                               table.insert(playerstacks, player_inv:remove_item("main", stack))
                           end
                           for i=1, coststacks do
                               price.count = cost_stack_max
                               player_inv:add_item("main", price)
                           end
                           if costremainder > 0 then
                               price.count = costremainder
                               player_inv:add_item("main", price)
                           end
                           if check_wear then
                               for o=1,#player_out do
                                   chest_inv:add_item("main", player_out[o].item)
                               end
                           else
                               for i=1,#playerstacks do
                                   chest_inv:add_item("main", playerstacks[i])
                               end
                           end
                           meta:set_string("message", "Item sold.")
                           easyvend.sound_deposit(pos)
                           easyvend.machine_check(pos, node)
                       end
                    end
                elseif chest_has and player_has then
                    if not player_free then
                        msg = "No room in your inventory!"
                        meta:set_string("message", msg)
                        easyvend.sound_error(sendername)
                    elseif not chest_free then
                        msg = "No room in the machine’s storage!"
                        meta:set_string("status", msg)
	                easyvend.machine_disable(pos, node, sendername)
                    end
                else
                    if not player_has then
                        msg = "You have insufficient materials!"
                        meta:set_string("message", msg)
                        easyvend.sound_error(sendername)
                    elseif not chest_has then
                        msg = "The depositing machine is out of money!"
                        meta:set_string("status", msg)
	                easyvend.machine_disable(pos, node, sendername)
                    end
                end
            end
        else
            meta:set_string("status", "Storage can’t be accessed because it is owned by a different person!")
	    easyvend.machine_disable(pos, node, sendername)
        end
    else
        if sender and sender:is_player() then
            meta:set_string("status", "No storage; machine needs a locked chest below it.")
	    easyvend.machine_disable(pos, node, sendername)
        end
    end

    easyvend.set_formspec(pos, sender)
    
end

easyvend.after_place_node = function(pos, placer)
    local node = minetest.get_node(pos)
	local meta = minetest.get_meta(pos)
    local inv = meta:get_inventory()
    local player_name = placer:get_player_name()
    inv:set_size("item", 1)
    inv:set_size("gold", 1)
    
    inv:set_stack( "gold", 1, easyvend.currency )

    local d = ""
    if node.name == "easyvend:vendor" then
        d = string.format("Inactive vending machine (owned by %s)", player_name)
        meta:set_int("wear", 1)
    elseif node.name == "easyvend:depositor" then
        d = string.format("Inactive depositing machine (owned by %s)", player_name)
        meta:set_int("wear", 0)
    end
    meta:set_string("infotext", d)
    local chest = minetest.get_node({x=pos.x,y=pos.y-1,z=pos.z})
    meta:set_string("status", "Awaiting configuration by owner.")
    meta:set_string("message", "Welcome! Please prepare the machine.")
    meta:set_int("number", 1)
    meta:set_int("cost", 1)
    meta:set_int("stock", -1)
    meta:set_int("configmode", 1)
    meta:set_int("joketimer", -1)
    meta:set_int("joke_id", 1)
	meta:set_string("itemname", "")

	meta:set_string("owner", player_name or "")
    
    easyvend.set_formspec(pos, placer)
end

easyvend.can_dig = function(pos, player)
    local meta = minetest.get_meta(pos)
    local name = player:get_player_name()
    -- Owner can always dig shop
    if meta:get_string("owner") == name then
        return true
    end
    local chest = minetest.get_node({x=pos.x,y=pos.y-1,z=pos.z})
    local meta_chest = minetest.get_meta({x=pos.x,y=pos.y-1,z=pos.z});
    if registered_chests[chest.name] then
         if player and player:is_player() then
            local owner_chest = meta_chest:get_string(registered_chests[chest.name].meta_owner)
            if name == owner_chest then
                return true --chest owner can also dig shop
            end
         end
         return false
    else
        return true --if no chest, enyone can dig this shop
    end
end

easyvend.on_receive_fields = function(pos, formname, fields, sender)
	local meta = minetest.get_meta(pos)
	local node = minetest.get_node(pos)
	local owner = meta:get_string("owner")
	local sendername = sender:get_player_name(sender)
    
	if fields.config or fields.save or fields.usermode then
		if sender:get_player_name() == owner then
			easyvend.on_receive_fields_config(pos, formname, fields, sender)
		else
			meta:set_string("message", "Only the owner may change the configuration.")
			easyvend.sound_error(sendername)
			easyvend.set_formspec(pos, sender)
			return
		end
	elseif fields.wear ~= nil then
		if sender:get_player_name() == owner then
			if fields.wear == "true" then
				if easyvend.buysell(node.name) == "buy" then
					meta:set_string("message", "Used tools are now accepted.")
				else
					meta:set_string("message", "Used tools are now for sale.")
				end
				meta:set_int("wear", 1)
			elseif fields.wear == "false" then
				if easyvend.buysell(node.name) == "buy" then
					meta:set_string("message", "Used tools are now rejected.")
				else
					meta:set_string("message", "Used tools won’t be sold anymore.")
				end
				meta:set_int("wear", 0)
			end
			easyvend.set_formspec(pos, sender)
			return
		else
			meta:set_string("message", "Only the owner may change the configuration.")
			easyvend.sound_error(sendername)
			easyvend.set_formspec(pos, sender)
			return
		end
	elseif fields.buysell then
		easyvend.on_receive_fields_buysell(pos, formname, fields, sender)
	end
end

-- Jokes: Appear when machine exchanges currency for currency at equal rate

-- Vendor
local jokes_vendor = {
	"Thank you. You have made a vending machine very happy.",
	"Humans have a strange sense of humor.",
	"Let’s get this over with …",
	"Item “bought”.",
	"Tit for tat.",
	"Do you realize what you’ve just bought?",
}
-- Depositor
local jokes_depositor = {
	"Thank you, the money started to smell inside.",
	"Money doesn’t grow on trees, you know?",
	"Sanity sold.",
	"Well, that was an awkward exchange.",
	"Are you having fun?",
	"Is this really trading?",
}

easyvend.assign_joke = function(buysell)
	local jokes
	if buysell == "sell" then
		jokes = jokes_vendor
	elseif buysell == "buy" then
		jokes = jokes_depositor
	end
	local r = math.random(1,#jokes)
	return r
end

easyvend.get_joke = function(buysell, id)
	local joke
	if buysell == nil or id == nil then
		-- Fallback message (should never happen)
		return "Items exchanged."
	end
	if buysell == "sell" then
		joke = jokes_vendor[id]
		if joke == nil then joke = jokes_vendor[1] end
	elseif buysell == "buy" then
		joke = jokes_depositor[id]
		if joke == nil then joke = jokes_depositor[1] end
	end
	return joke
end

easyvend.sound_error = function(playername) 
	minetest.sound_play("easyvend_error", {to_player = playername, gain = 0.25})
end

easyvend.sound_setup = function(pos)
	minetest.sound_play("easyvend_activate", {pos = pos, gain = 0.5, max_hear_distance = 12,})
end

easyvend.sound_disable = function(pos)
	minetest.sound_play("easyvend_disable", {pos = pos, gain = 0.9, max_hear_distance = 12,})
end

easyvend.sound_vend = function(pos) 
	minetest.sound_play("easyvend_vend", {pos = pos, gain = 0.4, max_hear_distance = 5,})
end

easyvend.sound_deposit = function(pos)
	minetest.sound_play("easyvend_deposit", {pos = pos, gain = 0.4, max_hear_distance = 5,})
end

easyvend.allow_metadata_inventory_put = function(pos, listname, index, stack, player)
    if listname=="item" then
        local meta = minetest.get_meta(pos);
        local owner = meta:get_string("owner")
        local name = player:get_player_name()
        if name == owner then
            local inv = meta:get_inventory()
            if stack==nil then
                inv:set_stack( "item", 1, nil )
            else
                inv:set_stack( "item", 1, stack:get_name() )
                meta:set_string("itemname", stack:get_name())
                easyvend.set_formspec(pos, player)
            end
        end
    end
	return 0
end

easyvend.allow_metadata_inventory_take = function(pos, listname, index, stack, player)
	return 0
end

easyvend.allow_metadata_inventory_move = function(pos, from_list, from_index, to_list, to_index, count, player)
	return 0
end

minetest.register_abm({
	nodenames = {"easyvend:vendor", "easyvend:vendor_on", "easyvend:depositor", "easyvend:depositor_on"},
	interval = 5,
	chance = 1,
	catch_up = false,
	action = function(pos, node, active_object_count, active_object_count_wider)
		easyvend.machine_check(pos, node)
	end
})

-- Legacy support for vendor mod:
-- Transform the world and items to use the easyvend nodes/items

-- For safety reasons, only do this when player requested so
if minetest.setting_getbool("easyvend_convert_vendor") == true then
	-- Replace vendor nodes
	minetest.register_lbm({
		name = "easyvend:replace_vendor",
		nodenames = { "vendor:vendor", "vendor:depositor" },
		run_at_every_load = true,
		action = function(pos, node)
			local newnodename
			if node.name == "vendor:vendor" then
				newnodename = "easyvend:vendor"
			elseif node.name == "vendor:depositor" then
				newnodename = "easyvend:depositor"
			end
			minetest.swap_node(pos, { name = newnodename, param2 = node.param2 })
			local meta = minetest.get_meta(pos)
			meta:set_string("status", "Initializing …")
			meta:set_string("message", "Upgrade successful.")
			meta:set_int("stock", -1)
			meta:set_int("joketimer", -1)
			meta:set_int("joke_id", 1)
			local inv = meta:get_inventory()
			inv:set_size("item", 1)
			inv:set_size("gold", 1)
			inv:set_stack("gold", 1, easyvend.currency)

			local itemname = meta:get_string("itemname")
			local configmode = 1
			if itemname == "" or itemname == nil then
				-- If no itemname set, try to scan first item in chest below
				local chest = minetest.get_node({x=pos.x,y=pos.y-1,z=pos.z})
				if chest.name == "default:chest_locked" then
					local chest_meta = minetest.get_meta({x=pos.x,y=pos.y-1,z=pos.z})
					local chest_inv = chest_meta:get_inventory()
					if ( chest_meta:get_string("owner") == machine_owner and chest_inv ~= nil ) then
					end
					for i=1,chest_inv:get_size("main") do
						checkstack = chest_inv:get_stack("main", i)
						if not checkstack:is_empty() then
							itemname = checkstack:get_name()
							break
						end
					end
				end
				if itemname ~= "" and itemname ~= nil then
					inv:set_stack("item", 1, itemname)
					meta:set_string("itemname", itemname)
				end
			end
			if itemname ~= "" and itemname ~= nil then
				local itemstack = inv:get_stack("item", 1)
				local number_stack_max = itemstack:get_stack_max()
				local maxnumber = number_stack_max * slots_max
				local cost = meta:get_int("cost")
				local number = meta:get_int("number")
				if number >= 1 and number <= maxnumber and cost >= 1 and cost <= maxcost then
					configmode = 0
				end
			end

			local owner = meta:get_string("owner")
			if easyvend.buysell(newnodename) == "sell" then
				meta:set_string("infotext", string.format("Vending machine (owned by %s)", owner))
			else
				meta:set_string("infotext", string.format("Depositing machine (owned by %s)", owner))
			end

			meta:set_int("configmode", configmode)
			easyvend.machine_check(pos, node)
		end,
	})
end