-- "I'll stop calling it Minetest when it stops being one."
minetest = core

-- Override properties of a table from those of another table
function extend(dst, src)
    for k, v in pairs(src) do
        dst[k] = v
    end
    return dst
end

table.merge = extend

-- PHP-style helper verb
function include(file)
    return dofile(minetest.get_modpath(minetest.get_current_modname()).."/"..file)
end

function include_all(dir)
    for _, x in pairs(minetest.get_dir_list(minetest.get_modpath(minetest.get_current_modname()).."/"..dir)) do
        include(dir.."/"..x)
    end
end

function warn(str)
    minetest.log("warning", str)
end

function err(str)
    minetest.log("error", str.."\n"..debug.traceback())
end

function tell(p, msg)
    minetest.chat_send_player(p, "# Server: "..msg)
end

function say(msg)
    minetest.chat_send_all("# Server: "..msg)
end

EventTarget = {
    init = function()
        local e = {
            listeners = {}
        }
        return setmetatable(e, {__index = EventTarget})
    end,
    listen = function(e, channel, fn)
        if not e.listeners[channel] then e.listeners[channel] = {} end
        local l = e.listeners[channel]
        l[#l +1] = fn
    end,
    unlisten = function(e, channel, fn)
        if not e.listeners[channel] then return end
        local l = e.listeners[channel]
        local idx = table.indexof(l, fn)
        if idx < 0 then return end
        table.remove(l, idx)
    end,
    dispatch = function(e, channel, ...)
        local l = e.listeners[channel]
        if not l then return end
        for i = 1, #l do
            if l[i] then l[i](...) end
        end
    end
}
setmetatable(EventTarget, {
    __call = function(_, ...) return EventTarget.init(...) end
})

StateMachine = {
    init = function(obj, states)
        local super = EventTarget()
        local e = table.merge(super, {
            states = states,
            active_states = {},
            obj = obj
        })
        return setmetatable(e, {__index = StateMachine})
    end,
    add_state = function(e, state)
        if e.active_states[state] then return false end
        if e.states[state].excludes then
            for i = 1, #e.states[state].excludes do
                if e.active_states[e.states[state].excludes[i]] then
                    e:remove_state(e.states[state].excludes[i])
                end
            end
        end
        e.states[state]:add(e.obj)
        e.active_states[state] = true
        return true
    end,
    tick = function(e)
        for k in pairs(e.active_states) do
            e.states[k]:tick(e.obj)
        end
    end,
    remove_state = function(e, state)
        if not e.active_states[state] then return false end
        e.states[state]:remove(e.obj)
        e.active_states[state] = nil
        return true
    end,
}
setmetatable(StateMachine, {
    __call = function(_, ...) return StateMachine.init(...) end,
    __index = EventTarget()
})

ModifierStack = {
    init = function(mode)
        local e = EventTarget()
        extend(e, {
            mode = mode or "add",
            value = 0
        })
        return setmetatable(e, {__index = ModifierStack})
    end,
    set = function(e, key, value)
        if key == "value" then return end
        if e[key] then
            if e.mode == "multiply" then
                e.value = e.value /e[key]
            else
                e.value = e.value -e[key]
            end
        end
        e[key] = value
        if e[key] then
            if e.mode == "multiply" then
                e.value = e.value *e[key]
            else
                e.value = e.value +e[key]
            end
        end
        e:dispatch("change")
    end,
}
setmetatable(ModifierStack, {
    __call = function(_, ...) return ModifierStack.init(...) end,
    __index = EventTarget
})

rgt = {
    adjacent_neighbor_offests = {
        vector.new(0,0,1),
        vector.new(0,0,-1),
        vector.new(1,0,0),
        vector.new(-1,0,0),
        vector.new(1,0,1),
        vector.new(1,0,-1),
        vector.new(-1,0,1),
        vector.new(-1,0,-1),
    },
    adjacent_horizontal_neighbor_offests = {
        vector.new(0,0,1),
        vector.new(0,0,-1),
        vector.new(1,0,0),
        vector.new(-1,0,0),
    },
    abutting_neighbor_offests = {
        vector.new(0,0,1),
        vector.new(0,0,-1),
        vector.new(1,0,0),
        vector.new(-1,0,0),
        vector.new(0,1,0),
        vector.new(0,-1,0),
    },
    nodes_to_content_ids = {},
    content_ids_to_nodes = {},
    vm_data = {},
}
local ns = rgt

function ns.register_node(name, def)
    def._name = name
    local alias
    if not name:find(":") then
        alias = name
        name = "red_glazed_terracotta:"..name
    end
    if def.groups then
        if def.groups.interactable then
            def.on_rightclick = function(pos, _, p)
                rgt.players[p:get_player_name()].interacting_with = pos
            end
        end
    end
    if def._variants then
        if type(def._variants) == "string" then
            rgt_world["register_"..def._variants](def)
        else
            for _, x in ipairs(def._variants) do
                rgt_world["register_"..x](def)
            end
        end
    end
    minetest.register_node(":"..name, def)
    local cid = minetest.get_content_id(name)
    ns.nodes_to_content_ids[name] = cid
    ns.content_ids_to_nodes[cid] = name
    if alias then
        minetest.register_alias(alias, name)
    end
end

function ns.register_item(name, def)
    def._name = name
    local alias
    if not name:find(":") then
        alias = name
        name = "red_glazed_terracotta:"..name
    end
    minetest.register_craftitem(":"..name, def)
    if alias then
        minetest.register_alias(alias, name)
    end
end

function ns.register_tool(name, def)
    def._name = name
    local alias
    if not name:find(":") then
        alias = name
        name = "red_glazed_terracotta:"..name
    end
    minetest.register_tool(":"..name, def)
    if alias then
        minetest.register_alias(alias, name)
    end
end

function ns.register_entity(name, def)
    def._name = name
    if not name:find(":") then
        name = "red_glazed_terracotta:"..name
    end
    minetest.register_entity(":"..name, def)
end

-- Make node dig particles denser.
minetest.register_on_dignode(function(pos, node, digger)
    local gravity = tonumber(core.settings:get("movement_gravity")) or 9.81
    local def = minetest.registered_nodes[node.name]
    minetest.add_particlespawner({
        amount = 128,
        time = 0.001,
        minpos = vector.offset(pos, -0.35, -0.35, -0.35),
        maxpos = vector.offset(pos, 0.35, 0.35, 0.35),
        minvel = vector.new(-1.7, 0, -1.7),
        maxvel = vector.new(1.7, 3.5, 1.7),
        minacc = vector.new(0, -gravity *2, 0),
        maxacc = vector.new(0, -gravity *2, 0),
        minexptime = 0, maxexptime = 1,
        minsize = 0, maxsize = 0, -- random
        node = node,
        minsize = 0.5,
        maxsize = 1.4,
        blend = (def and def.use_texture_alpha == "blend") and "blend" or "clip",
    })
end)

-- HACK: Lookup table for getting a rotation from a
-- facedir (because Minetest doesn't have any way
-- to get this information normally)
local facedir_rotations = {
    -- +Y
    [0] = vector.new(0, 0, 0),
    [1] = vector.new(0, math.pi * 1.5, 0),
    [2] = vector.new(0, math.pi * 1.0, 0),
    [3] = vector.new(0, math.pi * 0.5, 0),
    -- +Z
    [4] = vector.new(math.pi * 1.5, 0, 0),
    [5] = vector.new(0, math.pi * 1.5, math.pi * 1.5),
    [6] = vector.new(math.pi * 0.5, math.pi * 1.0, 0),
    [7] = vector.new(0, math.pi * 0.5, math.pi * 0.5),
    -- -Z
    [8] = vector.new(math.pi * 0.5, 0, 0),
    [9] = vector.new(0, math.pi * 1.5, math.pi * 0.5),
    [10] = vector.new(math.pi * 1.5, math.pi * 1.0, 0),
    [11] = vector.new(0, math.pi * 0.5, math.pi * 1.5),
    -- +X
    [12] = vector.new(0, 0, math.pi * 0.5),
    [13] = vector.new(math.pi * 1.5, math.pi * 1.5, 0),
    [14] = vector.new(0, math.pi * 1.0, math.pi * 1.5),
    [15] = vector.new(math.pi * 0.5, math.pi * 0.5, 0),
    -- -X
    [16] = vector.new(0, 0, math.pi * 1.5),
    [17] = vector.new(math.pi * 0.5, math.pi * 1.5, 0),
    [18] = vector.new(0, math.pi * 1.0, math.pi * 0.5),
    [19] = vector.new(math.pi * 1.5, math.pi * 0.5, 0),
    -- -Y
    [20] = vector.new(0, 0, math.pi * 1.0),
    [21] = vector.new(0, math.pi * 0.5, math.pi * 1.0),
    [22] = vector.new(0, math.pi * 1.0, math.pi * 1.0),
    [23] = vector.new(0, math.pi * 1.5, math.pi * 1.0),
}

function ns.facedir_to_rotation(facedir)
    return facedir_rotations[facedir] or minetest.facedir_to_dir(facedir):dir_to_rotation()
end

-- Fills the area from pos1 to pos2 with the node named `node`.
function ns.fill_area(pos1, pos2, node)
    local minp = vector.new(math.min(pos1.x, pos2.x), math.min(pos1.y, pos2.y), math.min(pos1.z, pos2.z))
    local maxp = vector.new(math.max(pos1.x, pos2.x), math.max(pos1.y, pos2.y), math.max(pos1.z, pos2.z))
    local vm = minetest.get_voxel_manip(pos1, pos2)
    local min, max = vm:get_emerged_area()
    local va = VoxelArea(min, max)
    local data = ns.vm_data
        
    vm:get_data(data)
    
    local c_node = minetest.get_content_id(node)
    for i in va:iterp(minp, maxp) do
        data[i] = c_node
    end
    
    vm:set_data(data)
    vm:write_to_map()
    if vm.close then vm:close() end
end

-- Get a flat texture that may represent the given node (using the first tile).
function ns.get_node_texture(node)
    local def = minetest.registered_nodes[node]
    if not def or not def.tiles then return "blank.png" end
    local tx = def.tiles[1]
    if type(tx) == "string" then
        return tx
    end
    return tx.name or "blank.png"
end

-- Out-of-line node metadata, allowing meta for a node to be accessed even when its containing mapblock is not loaded.
local db = minetest.get_mod_storage()
local NodeMetaRef = {
    set = function(e, key, value)
        return db:set_string(e._pos.."_"..key, value)
    end,
    get = function(e, key)
        return db:get(e._pos.."_"..key)
    end,
}
NodeMetaRef.__index = NodeMetaRef

function ns.get_node_meta(pos)
    return setmetatable({_pos = tostring(minetest.hash_node_position(pos))}, NodeMetaRef)
end

ns.clock = EventTarget()

local seconds = minetest.get_us_time()
minetest.register_globalstep(function(dtime)
    ns.clock:dispatch("tick", dtime)
    local time = minetest.get_us_time()
    if time - seconds >= 1000000 then
        ns.clock:dispatch("every_second", dtime)
        seconds = time
    end
end)

-- Allow nodes to provide a callback to run on activation without
-- needing to register a bunch of mostly identical LBMs.
minetest.register_lbm {
    name = ":red_glazed_terracotta:on_activate",
    nodenames = {"group:run_on_activate"},
    action = function(pos, node)
        minetest.registered_nodes[node.name].on_activate(pos)
    end
}


minetest.register_on_joinplayer(function(p)
    if p:get_player_name() == "singleplayer" then
        minetest.change_player_privs(p:get_player_name(), {
            fast = true,
            fly = true,
            noclip = true,
            server = true,
            give = true,
        })
    end
end)