spawners/spawners_ores/api.lua

--[[
    Ore spawners let player craft ore spawneres and get back lumps from ingots.
    Copyright (C) 2016 - 2023 SaKeL <juraj.vajda@gmail.com>

    This library is free software; you can redistribute it and/or
    modify it pos 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 library 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
    Lesser 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 juraj.vajda@gmail.com
--]]

-- main tables
spawners_ores = {}
local percent = 10

-- how often node timers for minerals will tick, +/- some random value
function spawners_ores.tick(pos)
    minetest.get_node_timer(pos):start(math.random(30, 60))
end

-- how often a growth failure tick is retried (e.g. not enough place to spawn minerals)
function spawners_ores.tick_short(pos)
    minetest.get_node_timer(pos):start(math.random(15, 20))
end

-- adds smoke particles
function spawners_ores.add_effects(pos, radius)
    minetest.add_particlespawner({
        amount = 32,
        time = 2,
        minpos = vector.subtract({ x = pos.x, y = pos.y + 1, z = pos.z }, radius / 2),
        maxpos = vector.add({ x = pos.x, y = pos.y + 1, z = pos.z }, radius / 2),
        minvel = { x = -0.5, y = 3, z = -0.5 },
        maxvel = { x = 0.5, y = 10, z = 0.5 },
        minacc = vector.new(),
        maxacc = vector.new(),
        minexptime = 0.5,
        maxexptime = 2,
        minsize = 0.5,
        maxsize = 8,
        texture = 'spawners_ores_smoke_particle.png^[transform' .. math.random(0, 3)
    })
end

-- start spawning ores
function spawners_ores.start_spawning_ores(pos, ore_name, how_many)
    if not pos or not ore_name then return end
    local _how_many = how_many or 1

    for i = 1, _how_many do

        if i > 1 then
            pos = spawners_ores.get_available_node(pos, 'default:stone')

            if not pos then return end

            minetest.sound_play('spawners_ores_strike', {
                pos = pos,
                max_hear_distance = 16,
                gain = 10,
            })

            minetest.set_node(pos, { name = ore_name })
            spawners_ores.add_effects(pos, 1)
        else
            minetest.sound_play('spawners_ores_strike', {
                pos = pos,
                max_hear_distance = 16,
                gain = 10,
            })

            minetest.set_node(pos, { name = ore_name })
            spawners_ores.add_effects(pos, 1)
        end
    end

end

function spawners_ores.get_available_node(pos, check_node, radius)
    if not pos then return end

    local _check_node = check_node or 'default:stone'
    local _radius = radius or 2

    local node_ore_pos = minetest.find_node_near(pos, _radius, { _check_node })

    if node_ore_pos and node_ore_pos ~= nil then
        return node_ore_pos
    else
        return false
    end
end

-- build form for spawners
function spawners_ores.get_formspec(pos, table)
    -- Inizialize metadata and variables
    local _table = table or {}
    local meta = minetest.get_meta(pos)
    local mineral = _table.ore or meta:get_string('mineral')
    local ingot = _table.ore or meta:get_string('mineral')
    local status = meta:get_string('status')
    local inv = meta:get_inventory()
    local stack = inv:get_stack('fuel', 1)

    -- fix different Ingot namings
    if ingot == 'iron' then
        ingot = 'steel'
    end

    -- add extra ores based on percentage
    local stack_per_obj = spawners_ores.stack_per({
        stack_count = stack:get_count(),
        percent = percent
    })
    local stack_per = stack_per_obj.stack_per or 0
    local extra_per = stack_per_obj.extra_per or 0

    local colorize = {
        gold = '^[colorize:#ffe4008C',
        tin = '^[colorize:#d0d0d08C',
        iron = '^[colorize:#b66d498C',
        copper = '^[colorize:#b587528C',
    }

    local colorize_arrow = ''
    local button = ''

    if status == 'active' then
        colorize_arrow = colorize[mineral]
    elseif status == 'waiting' then
        button = 'button[1.8,2.5;2,1.5;restart;RE-START]'
    end

    -- dynamic formspec
    local formspec = 'size[8,8.5]' ..
        default.gui_bg ..
        default.gui_bg_img ..
        default.gui_slots ..
        'label[1.8,0.3;Input ' .. ingot .. ' Ingot]' ..
        'list[current_name;fuel;1.8,1;1,1;]' ..
        'image[1.8,1;1,1;spawners_ores_ingot_slot.png]' ..
        'list[current_player;main;0,4.25;8,1;]' ..
        'list[current_player;main;0,5.5;8,3;8]' ..
        'image[2.9,1;1,1;gui_furnace_arrow_bg.png^[transformR270' .. colorize_arrow .. ']' ..
        'label[1.8,2;' .. stack_per .. ' minerals (' .. extra_per .. ' extra)]' ..
        'image[4,1;1,1;spawners_ores_stone_with_' .. mineral .. '.png]' ..
        button ..
        'listring[current_name;fuel]' ..
        'listring[current_player;main]' ..
        default.get_hotbar_bg(0, 4.25)

    meta:set_string('formspec', formspec)

    -- infotext
    local infotext = mineral .. ' fuel: ' .. inv:get_stack('fuel', 1):get_count()

    if inv:is_empty('fuel') then
        infotext = mineral .. ' ore spawner is empty.'
    elseif status == 'waiting' then
        infotext = 'Waiting - no default:stone was found near by, ' .. mineral .. ' fuel: ' .. inv:get_stack('fuel', 1):get_count()
    end

    meta:set_string('infotext', infotext)
end

-- check if is fuel empty in the node
function spawners_ores.can_dig(pos, player)
    local meta = minetest.get_meta(pos);
    local inv = meta:get_inventory()
    return inv:is_empty('fuel')
end

-- add extra percentage on top of the stack
function spawners_ores.stack_per(table)
    local _table = table or {}
    local stack_count = _table.stack_count or nil
    local extra_per = (stack_count / 100) * percent

    extra_per = math.floor(extra_per)

    local stack_per = extra_per + stack_count

    -- print(percent .. '% from stack(' .. stack_count .. ') = ' .. stack_per .. ' (' .. extra_per .. ' extra ore(s))')

    return {
        stack_per = stack_per,
        extra_per = extra_per
    }
end

-- set status and update formspec/infotext
function spawners_ores.on_timer(pos, elapsed)

    local available_node = spawners_ores.get_available_node(pos, 'default:stone')

    local meta = minetest.get_meta(pos)
    local inv = meta:get_inventory()
    local stack = inv:get_stack('fuel', 1)
    local how_many = 1

    local ore_name = meta:get_string('ore_name')
    local status = meta:get_string('status')
    local tick = meta:get_int('tick')

    --
    -- active
    --
    if available_node and inv:is_empty('fuel') ~= true then
        -- make sure the right node status is shown
        if status ~= 'active' then
            meta:set_string('status', 'active')

            spawners_ores.get_formspec(pos)
            minetest.swap_node(pos, { name = 'spawners_ores:' .. ore_name .. '_spawner_active' })
        end

        -- start spawning only on proper 'tick'
        if tick ~= 0 then
            if stack:get_count() % percent == 0 then
                -- TODO: should get countent based on 'percent'
                how_many = 2
            end

            -- enough place to spawn more ores
            spawners_ores.start_spawning_ores(available_node, 'default:' .. ore_name, how_many)

            -- take fuel
            stack:take_item()
            inv:set_stack('fuel', 1, stack)

            spawners_ores.get_formspec(pos)
        end

        -- dont wait for proper 'tick' and change state after 1 sec.
        local next_available_node = spawners_ores.get_available_node(pos, 'default:stone')

        if inv:is_empty('fuel') or next_available_node == false then
            minetest.get_node_timer(pos):start(1.0)
            return
        end

        if tick == 0 then
            -- start new proper timer
            meta:set_int('tick', 1)
        end

        -- start new proper timer
        spawners_ores.tick(pos)
    --
    -- default
    --
    elseif inv:is_empty('fuel') then
        -- empty / no fuel -- stop timer
        -- make sure that default status/node is shown
        meta:set_string('status', '')
        minetest.swap_node(pos, { name = 'spawners_ores:' .. ore_name .. '_spawner' })

        spawners_ores.get_formspec(pos)
        return

    --
    -- waiting
    --
    else
        -- stop timer and show 'refresh' button in order to start timer again
        -- make sure that waiting status/node is shown
        if status ~= 'waiting' then
            meta:set_string('status', 'waiting')
            minetest.swap_node(pos, { name = 'spawners_ores:' .. ore_name .. '_spawner_waiting' })
        end

        spawners_ores.get_formspec(pos)
        return
    end
end