-- occompass
-- Optionally places a compass and/or a bearing device on the screen
-- Descended from a mod by David_G (kestral246@gmail.com)
-- This version is by Robert Kiraly (OldCoder)

local get_png = function (basepng)
    return basepng
end

occompass.param_compass = {
    hud_elem_type="image", text="",
    position  = { x =  1 , y = 0 } , scale  = { x =  1 , y = 1 } ,
    alignment = { x = -1 , y = 1 } , offset = { x = -8 , y = 4 } ,
}

ocbearing.param_bearing = {
    hud_elem_type="image", text="",
    position  = { x =  1 , y = 0 } , scale  = { x =  1 , y = 1 } ,
    alignment = { x = -1 , y = 1 } , offset = { x = -8 , y = 4 } ,
}

if  occompass.enable_compass and
    occompass.enable_bearing then
    ocbearing.param_bearing.position.y = 0.15
end

minetest.register_on_joinplayer (function(player)
    local pname = player:get_player_name()

    if occompass.enable_bearing then
        ocbearing [pname] = {
            id_bearing = player:hud_add (ocbearing.param_bearing) ,
            last_image = -1 ,
            state      =  1 ,
            counter    =  0 ,
        }
    end

    if occompass.enable_compass then
        occompass [pname] = {
            id_compass = player:hud_add (occompass.param_compass) ,
            last_image = -1 ,
            state      =  1 ,
            counter    =  0 ,
        }
    end
end)

minetest.register_on_leaveplayer (function (player)
    if player == nil then return end
    local pname = player:get_player_name()
    if pname  == nil then return end

    if  ocbearing [pname] then
        ocbearing [pname] = nil
    end

    if  occompass [pname] then
        occompass [pname] = nil
    end
end)

local bearing_cache = {}
local compass_cache = {}

minetest.register_globalstep (function (dtime)
    local players  = minetest.get_connected_players()

    for i,player in ipairs (players) do
        local pname = player:get_player_name()
        local dir

        if pname ~= nil then
            dir = player:get_look_horizontal()
        end

        if pname ~= nil and ocbearing [pname] ~= nil then
            local angle_relative = 360 - math.deg (dir)
            if    angle_relative <    0 then angle_relative = 0 end
            if    angle_relative >= 360 then angle_relative = 0 end

            local image_bearing  = math.floor ((angle_relative / 22.5)
+ 0.5) % 16
            if  ocbearing [pname].last_image ~= image_bearing then
                local png = bearing_cache [image_bearing]

                if  png == nil then
                    png =  get_png ("ocbearing_bg.png^ocbearing_" ..
image_bearing .. ".png")
                    bearing_cache [image_bearing] = png
                end

                local rc = player:hud_change (ocbearing  [pname].id_bearing,
"text", png)
                if rc == 1 then
                    ocbearing [pname].last_image = image_bearing
                end
            end
        end

        if pname ~= nil and occompass [pname] ~= nil then
            local angle_relative = math.deg (dir)
            if    angle_relative <    0 then angle_relative = 0 end
            if    angle_relative >= 360 then angle_relative = 0 end

            local image_compass  = math.floor ((angle_relative / 22.5)
+ 0.5) % 16
            if  occompass [pname].last_image ~= image_compass then
                local png = compass_cache [image_compass]
                if  png == nil then
                    png =  get_png ("occompass_" ..
image_compass .. ".png")
                    compass_cache [image_compass] = png
                end

                local rc = player:hud_change (occompass [pname].id_compass,
"text", png)
                if rc == 1 then
                    occompass [pname].last_image = image_compass
                end
            end
        end
    end
end)