Global Vehicle Meta-Ids v2 for SAPP

-- Global Vehicle Meta-Ids v2  (Utility Script for scripting with SAPP, not a game-play script)
-- by H® Shaft and Giraffe (could not have done this script without Giraffes help)

-- This script will display a list of vehicle meta-ids in the map, along with vehicle names (if there is one)
-- Works with BOTH protected and unprotected Halo PC/CE maps!

-- Purpose of this script?
    -- This script is a utility script to aid in script and game development
    -- using a lua script, you can spawn any vehicle, in any game type, or replace any vehicle with another vehicle, or block from spawning
    -- But, you will first need the meta-id of those vehicles you wish to spawn, replace or block

-- This will display and log (see USAGE below):
    -- 1) a complete list of all vehicle meta-id listed in the map,
    -- 2) list of all vehicle meta-id listed in the globals tag, or -
    -- 3) a single vehicle meta-id into sapps log file with the map name

-- Usage - Type the command (without quotes):
    -- 1) "all_vehicles"        |- to see and save a list of all vehicle meta-ids in the map
    -- 2) "global_vehicles"     |- to see and save a list of all vehicle meta-ids in the globals tag
    -- 3) "this_vehicle"        |- to see and save a single meta-id of the vehicle you are IN

-- Sample Output ("global_vehicles") Displayed on screen, and logged into sapp.log:

    -- There are 6 vehicles listed in the map bloodgulch (PC/CE):
    -- Vehicle # 1: Meta ID: 3822322272 Name: Warthog
    -- Vehicle # 2: Meta ID: 3837199171 Name: Ghost
    -- Vehicle # 3: Meta ID: 3830907619 Name: Scorpion
    -- Vehicle # 4: Meta ID: 3846177740 Name: Warthog
    -- Vehicle # 5: Meta ID: 3899197173 Name: Banshee
    -- Vehicle # 6: Meta ID: 3842311057 Name: Gun Turret

-- Map Globals
-- Each map has a standard list of SIX vehicle 'slots', this is the "stock" slot list (Globals Tag).
-- This slot list matches the multiplayer gametype 'vehicle options' screen, in the halo lobby 'Edit Gametypes' section:

-- Slot 1: Warthog
-- Slot 2: Ghost
-- Slot 3: Scorpion
-- Slot 4: Rocket Warthog
-- Slot 5: Banshee
-- Slot 6: Gun Turret

-- Notes:
-- 'Stock' PC/CE maps always follow the above order, BUT, - not all "custom" Halo CE maps follow the above order.
-- The Custom map's author may have 'mixed the slot order', or - may not have used all six slots in the scenario, or
-- some vehicles in the map may have been spawned by a 'built-in' halo script. If so, they may NOT all be listed in the globals output (use all_vehicles instead)
-- Slots 1, 2 & 4 are the vehicles typically setup for RACE gametypes, and others will not 'usually' spawn during race games.
-- Stock PC/CE maps use the same meta-ids for each slot for both PC and CE stock maps (i.e. Warthog meta-id for PC AND CE is same#: 3822322272)
-- "Custom Maps" use meta-ids that are unique to each map, so the meta-id can only be used for each unique "Custom" map.

-- Vehicles in CE and Protected CE Maps:
    -- "names" of vehicles could be wrong IF:
    -- the maps author did not add tag a name for a "custom" vehicle, or used another vehicles "name" or model
    -- such as calling a "hornet" a "banshee"
    -- using the wrong id: such as using the warthog hud message text id# in the ghost vehicle tag (or custom vehicle tag)
    -- vehicles may not spawn by gametype settings if author failed to add that vehicle to the globals tag, but did add it in the scenario tag

-- sapp api version
api_version = "1.9.0.0"

function OnScriptLoad()
    register_callback(cb['EVENT_CHAT'], "OnPlayerChat")
    vehicle_index = {}
end

function OnPlayerChat(PlayerIndex, Message)
    local response = nil
    local Message = string.lower(Message)
    map_name = get_var(0,"$map")

    -- | retrieve and show/save the meta-id list for the entire map
    if (Message == "all_vehicles") then
        response = false
        if (get_var(0, "$gt") ~= "n/a") then
            local tag_array = read_dword(0x40440000)
            local tag_count = read_word(0x4044000C)
            local veh_index = 1
            vehicle_index[map_name] = {}
            execute_command('log_note "These are the vehicles listed in the entire map:"')
            say(PlayerIndex,"These are the vehicles listed in the entire map:")
            for i=0,tag_count-1 do
                local tag = tag_array + i*32
                if (read_dword(tag) == 0x76656869) then
                    local vehicle_metaid = read_dword(tag + 0xC)
                    if (vehicle_metaid ~= 0xFFFFFFFF) then
                        local vehicle_name_tag = get_vehicle_name(vehicle_metaid)
                        vehicle_index[map_name][1] = veh_index
                        vehicle_index[map_name][2] = vehicle_metaid
                        vehicle_index[map_name][3] = vehicle_name_tag
                        local str0 = string.format("Vehicle #%s: Meta ID: %s Name: %s", tostring(vehicle_index[map_name][1]), tostring(vehicle_index[map_name][2]), tostring(vehicle_index[map_name][3]))
                        say(PlayerIndex, str0)
                        execute_command("log_note \""..str0.."\"")
                        veh_index = veh_index + 1
                    end
                end
            end
        end
    end

    -- | retrieve and show/save the meta-id list for map from globals tag
    if (Message == "global_vehicles") then
        response = false
        if (get_var(0, "$gt") ~= "n/a") then
            local globals_tag = lookup_tag("matg", "globals\\globals")
            local globals_data = read_dword(globals_tag + 0x14)
            local mp_info_data = read_dword(globals_data + 0x168)
            local vehicles_count = read_dword(mp_info_data + 0x20)
            local vehicles_data = read_dword(mp_info_data + 0x24)
            vehicle_index[map_name] = {}
            if vehicles_count > 0 then
                local str1 = string.format("There are %s vehicles listed in the map globals %s:", tostring(vehicles_count),tostring(map_name))
                execute_command("log_note \""..str1.."\"")
                say(PlayerIndex,str1)
                local veh_index = 1
                for i=0,vehicles_count-1 do
                    local vehicle_metaid = read_dword(vehicles_data + i*16 + 0xC)
                    if (vehicle_metaid ~= 0xFFFFFFFF) then
                        local vehicle_name_tag = get_vehicle_name(vehicle_metaid)
                        vehicle_index[map_name][1] = veh_index
                        vehicle_index[map_name][2] = vehicle_metaid
                        vehicle_index[map_name][3] = vehicle_name_tag
                        local str2 = string.format("Vehicle #%s: Meta ID: %s Name: %s", tostring(vehicle_index[map_name][1]), tostring(vehicle_index[map_name][2]), tostring(vehicle_index[map_name][3]))
                        say(PlayerIndex, str2)
                        execute_command("log_note \""..str2.."\"")
                        veh_index = veh_index + 1
                    end
                end
                say(PlayerIndex, "This list was saved in the sapp log file.")
            else
                local str3 = string.format("There are no vehicles listed in %s, or there was an error.", tostring(map_name))
                say(PlayerIndex, str3)
                execute_command("log_note \""..str3.."\"")
            end
        end
    end

    -- | retrieve and show/save the meta-id for your current vehicle (you must be in a vehicle)
    if (Message == "this_vehicle") then
        response = false
        if (get_var(0, "$gt") ~= "n/a") then
            if isinvehicle(PlayerIndex) then
                local player_object = get_dynamic_player(PlayerIndex)
                local vehicle_id = read_dword(player_object + 0x11C)
                local veh_object = get_object_memory(vehicle_id)
                if (veh_object ~= 0) then
                    local vehicle_metaid = read_dword(veh_object)
                    if (vehicle_metaid ~= 0xFFFFFFFF) then
                        local vehicle_name_tag = get_vehicle_name(vehicle_metaid)
                        local data = string.format("Map: %s  Vehicle MetaId: %s Name or Tag: %s", tostring(map_name),tostring(vehicle_metaid), tostring(vehicle_name_tag))
                        execute_command("log_note \""..data.."\"")
                        say(PlayerIndex, data)
                        say(PlayerIndex, "This vehicle's meta-id was saved in the sapp log file.")
                    else
                        say(PlayerIndex, "Sorry, there was an error, no meta-data available.")
                    end
                end
            else
                say(PlayerIndex, "You must be in a vehicle to retrieve it's meta-data.")
            end
        end
    end

    return response
end

function get_vehicle_name(MetaID) -- Thanks to Giraffe!
    if (MetaID == 0xFFFFFFFF) then
        return "NULL METAID"
    else
        local globals_tag = lookup_tag("matg", "globals\\globals")
        local globals_data = read_dword(globals_tag + 0x14)
        local interface_bitmaps_data = read_dword(globals_data + 0x144)
        local hud_globals_metaid = read_dword(interface_bitmaps_data + 0x6C)
        local hud_globals_tag = lookup_tag(hud_globals_metaid)
        local hud_globals_data = read_dword(hud_globals_tag + 0x14)
        local hud_icon_messages_metaid = read_dword(hud_globals_data + 0xC0)
        local hud_icon_messages_tag = lookup_tag(hud_icon_messages_metaid)
        local hud_icon_messages_data = read_dword(hud_icon_messages_tag + 0x14)
        local string_references_count = read_dword(hud_icon_messages_data)
        local string_references_data = read_dword(hud_icon_messages_data + 0x4)
        local strings = {}
        for i=0,string_references_count-1 do
            local bytes = read_dword(string_references_data + i*20)
            local string_data = read_dword(string_references_data + i*20 + 0xC)
            local string = ''
            for j=0,bytes-3,2 do
                string = string .. string.char(read_char(string_data +j))
            end
            strings[i] = string
        end
        local vehicle_tag = lookup_tag(MetaID)
        local vehicle_data = read_dword(vehicle_tag + 0x14)
        local hud_text_message_index = read_short(vehicle_data + 0x13C)
        if(strings[hud_text_message_index] ~= nil) then
            return strings[hud_text_message_index]
        else
            return strings[0]
        end
    end
end

function isinvehicle(PlayerIndex)
    local player_object = get_dynamic_player(PlayerIndex)
    if player_object ~= 0 then
        local vehicleId = read_dword(player_object + 0x11C)
        if vehicleId == 0xFFFFFFFF then
            return false
        else
            return true
        end
    else
        return false
    end
end

function OnScriptUnload()
    vehicle_index = {}
end

function OnError(Message)
    print(debug.traceback())
end

-- Created by H® Shaft, special thanks to Giraffe
-- Visit http://halorace.org/forum/index.php