local simple_alloy_furnace_recipes = {
    { recipe = { "sbz_chem:copper_powder", "sbz_chem:tin_powder" },        output = { "sbz_chem:bronze_powder" } },
    --    { recipe = { "sbz_chem:copper_powder", "sbz_chem:zinc_powder" },       output = { "sbz_chem:brass_powder" } },
    { recipe = { "sbz_chem:iron_powder", "sbz_chem:nickel_powder" },       output = { "sbz_chem:invar_powder" } },
    { recipe = { "sbz_chem:titanium_powder", "sbz_chem:aluminum_powder" }, output = { "sbz_chem:titanium_alloy_powder" } },
    --    { recipe = { "sbz_chem:gold_powder", "sbz_chem:nickel_powder" },       output = { "sbz_chem:white_gold_powder" } },
    -- uncomment to enable white gold or brass
}
minetest.after(0, function()
    for k, v in ipairs(simple_alloy_furnace_recipes) do
        unified_inventory.register_craft {
            output = v.output[1],
            type = "alloying",
            items = v.recipe
        }
    end
end)

sbz_api.simple_alloy_furnace_recipes = simple_alloy_furnace_recipes

sbz_api.register_stateful_machine("sbz_chem:simple_alloy_furnace", {
    description = "Simple Alloy Furnace",
    tiles = {
        "simple_alloy_furnace.png^[verticalframe:13:1"
    },
    groups = { matter = 1 },

    on_construct = function(pos)
        local meta = minetest.get_meta(pos)
        local inv = meta:get_inventory()
        inv:set_size("input", 2)
        inv:set_size("output", 1)

        meta:set_string("formspec", [[
formspec_version[7]
size[8.2,9]
style_type[list;spacing=.2;size=.8]
list[context;output;3.5,3;1,1;]
list[context;input;3,1;2,1;]
list[current_player;main;0.2,5;8,4;]
listring[current_player;main]
listring[context;input]
listring[current_player;main]
listring[context;output]
listring[current_player;main]
    ]])
    end,
    autostate = true,
    action = function(pos, node, meta, supply, demand)
        local power_needed = 10
        local inv = meta:get_inventory()

        local input_1 = inv:get_stack("input", 1):get_name()
        local input_2 = inv:get_stack("input", 2):get_name()

        local function is_valid_recipe(input1, input2)
            for _, recipe in ipairs(simple_alloy_furnace_recipes) do
                local r = recipe.recipe
                if (input1 == r[1] and input2 == r[2]) or (input1 == r[2] and input2 == r[1]) then
                    return recipe.output[1]
                end
            end
            return nil
        end

        local selected_item = is_valid_recipe(input_1, input_2)
        if selected_item == nil then
            meta:set_string("infotext", "Inactive")
            return 0
        end

        if demand + power_needed > supply then
            meta:set_string("infotext", "Not enough power")
            return power_needed, false
        else
            meta:set_string("infotext", "Smelting...")
            minetest.sound_play({ name = "simple_alloy_furnace_running", gain = 0.6 }, { pos = pos })

            if inv:room_for_item("output", selected_item) then
                inv:add_item("output", selected_item)
                inv:remove_item("input", input_1)
                inv:remove_item("input", input_2)
            else
                meta:set_string("infotext", "Output inventory full")
                return 0
            end

            return power_needed
        end
    end,
    input_inv = "input",
    output_inv = "output"
}, {
    tiles = {
        { name = "simple_alloy_furnace.png", animation = { type = "vertical_frames", length = 0.7 } }
    },
    light_source = 3,
})

minetest.register_craft({
    output = "sbz_chem:simple_alloy_furnace",
    recipe = {
        { "sbz_power:simple_charged_field", "sbz_resources:antimatter_dust",   "sbz_power:simple_charged_field" },
        { "sbz_resources:matter_blob",      "sbz_resources:emittrium_circuit", "sbz_resources:matter_blob" },
        { "sbz_power:simple_charged_field", "sbz_resources:matter_blob",       "sbz_power:simple_charged_field" }
    }
})
