--flatland mod
--by kddekadenz


--VARIABLES

n_top = "default:dirt_with_grass"
n_dn = "default:dirt"
lvl = 2

xlimit = 1000
ylimit = 1000
zlimit = 100


--CUSTOMIZING

--TODO: add possibility to change level ingame (previous tries made the game crash)
--TODO: prevent game from crashing when typing false name

minetest.register_on_chat_message(function(name, message, playername, player)
    local cmd = "/nt"
    if message:sub(0, #cmd) == cmd then
    nodet = string.match(message, cmd.." (.*)")
    if nodet ~= nil then
    n_top = nodet
    minetest.chat_send_player(name, "Node at level setted to: " ..nodet)
    return true
    end
    minetest.chat_send_player(name, 'usage: '..cmd..'node at level')
    return true
    end
end)


minetest.register_on_chat_message(function(name, message, playername, player)
    local cmd = "/nd"
    if message:sub(0, #cmd) == cmd then
    noded = string.match(message, cmd.." (.*)")
    if noded ~= nil then
    n_dn = noded
    minetest.chat_send_player(name, "Node below level setted to: " ..noded)
    return true
    end
    minetest.chat_send_player(name, 'usage: '..cmd..'node below level')
    return true
    end
end)


minetest.register_on_chat_message(function(name, message, playername, player)
    local cmd = "/water"
    if message:sub(0, #cmd) == cmd then
    n_top = "water_source"
    n_dn = "water_source"
    minetest.chat_send_player(name, "Enabled ocean mode")
    return true
    end
end)


minetest.register_on_chat_message(function(name, message, playername, player)
    local cmd = "/cloud"
    if message:sub(0, #cmd) == cmd then
    n_top = "cloud"
    n_dn = "air"
    minetest.chat_send_player(name, "Enabled cloud mode")
    return true
    end
end)

minetest.register_on_chat_message(function(name, message, playername, player)
    local cmd = "/desert"
    if message:sub(0, #cmd) == cmd then
    n_top = "desert_sand"
    n_dn = "desert_stone"
    minetest.chat_send_player(name, "Enabled desert mode")
    return true
    end
end)


minetest.register_on_chat_message(function(name, message, playername, player)
    local cmd = "/glass"
    if message:sub(0, #cmd) == cmd then
    n_top = "glass"
    n_dn = "air"
    minetest.chat_send_player(name, "Enabled glass mode")
    return true
    end
end)

minetest.register_on_chat_message(function(name, message, playername, player)
    local cmd = "/sand"
    if message:sub(0, #cmd) == cmd then
    n_top = "sand"
    n_dn = "sand"
    minetest.chat_send_player(name, "Enabled sand mode")
    return true
    end
end)

minetest.register_on_chat_message(function(name, message, playername, player)
    local cmd = "/grass"
    if message:sub(0, #cmd) == cmd then
    n_top = "dirt_with_grass"
    n_dn = "dirt"
    minetest.chat_send_player(name, "Enabled grass mode")
    return true
    end
end)



--GENERATING

minetest.register_on_generated(function(minp, maxp)
    if minetest.setting_getbool("flatland") then
        for x = -xlimit, xlimit do
            for z = -zlimit, zlimit do
                for ly = -ylimit, ylimit do
                local y = ylimit + -ylimit - ly
                local p = {x = x, y = y, z = z}
                        if y == lvl then
                        minetest.env:add_node(p, {name=n_top})
                        end
                            if y < lvl then
                            minetest.env:add_node(p, {name=n_dn})
                            end
                end
            end
        end
    end
    end
end)

minetest.register_on_generated(function(minp, maxp)
    if minetest.setting_getbool("flatland") then
        for x = minp.x, maxp.x do
            for z = minp.z, maxp.z do
                for ly = minp.y, maxp.y do
                local y = maxp.y + minp.y - ly
                local p = {x = x, y = y, z = z}
                    if y > lvl then
                    minetest.env:remove_node(p)
                    end

                    if y > ylimit then
                    minetest.env:remove_node(p)
                    end


                    if x > xlimit then
                    minetest.env:remove_node(p)
                    end


                    if z > zlimit then
                    minetest.env:remove_node(p)
                    end

                    if y < -ylimit then
                    minetest.env:remove_node(p)
                    end


                    if x < -xlimit then
                    minetest.env:remove_node(p)
                    end


                    if z < -zlimit then
                    minetest.env:remove_node(p)
                    end
                end
            end
        end
    end
end)