schemconvert/init.lua

---------------------------------------------------------------------------------------------------
-- schemconvert mod by A S Lewis
-- v1.0 22 Jun 2021
-- Lieence: LGPL 2.1
---------------------------------------------------------------------------------------------------

local S = minetest.get_translator(minetest.get_current_modname())

local mod_path = minetest.get_modpath(minetest.get_current_modname())

local file_list = {}
local convert_table = {}
local check_table = {}
local converted_table = {}
local not_converted_table = {}

local convert_count = 0
local error_count = 0

-- If enabled, show info/error messages in the chat window and debug file
local show_msg_flag = true

-- If enabled, the original .mts file is converted to a new .mts file, in which certain nodes
--      have been swapped for other nodes
local do_convert_flag = true

-- If enabled, the original .mts file is written as lua, so it can be compared with the converted
--      file
local write_original_lua_flag = false
-- If enabled, the converted .mts file is also written as lua, so it can be checked
local write_converted_lua_flag = false

-- If enabled, the original .mts file is displayed (as lua) in the chat window
local show_original_lua_flag = false
-- If enabled, the converted .mts file is displayed (as lua) in the chat window
local show_converted_lua_flag = false

-- If enabled, show a complete list of nodes that were convertd, and a complete list of nodes that
--      were not converted
local show_summary_flag = true

---------------------------------------------------------------------------------------------------
-- Handle messages
---------------------------------------------------------------------------------------------------

local function show_info(msg)
    if show_msg_flag then
        minetest.log("[SCHEMCONVERT] " .. msg)
    end
end

local function show_error(msg)
    if show_msg_flag then
        minetest.log("[SCHEMCONVERT] [ERROR] " .. msg)
    end
end

---------------------------------------------------------------------------------------------------
-- Helper functions
---------------------------------------------------------------------------------------------------

-- See if the file exists
local function file_exists(path)

    -- Adapted from https://stackoverflow.com/questions/11201262/how-to-read-data-from-a-file-in-lua

    local f = io.open(path, "rb")
    if f then
        f:close()
    end

    return f ~= nil

end

-- Get all lines from a file, return an empty list/table if the file does not exist
-- Ignore empty lines, and lines beginning with the # character
-- If a pattern is specified, ignore non-matching lines
local function lines_from(local_path, match_pattern)

    -- Adapted from https://stackoverflow.com/questions/11201262/how-to-read-data-from-a-file-in-lua

    if not file_exists(local_path) then return {} end

    local lines = {}
    for line in io.lines(local_path) do

        if string.match(line, "%a") and
                line:sub(1,1) ~= "#" and
                (match_pattern == nil or string.match(line, match_pattern)) then

            lines[#lines + 1] = line

        end

    end

    return lines

end

-- Read a CSV file, returning its contents as a table. Ignore empty lines, and lines beginning with
--      the # character
local function read_csv(local_path)

    -- Adapted from lib_materials/csv.lua

    local file = io.open(local_path, "r")
    local return_table = {}
    local separator = "|"

    for line in file:lines() do

        if line:sub(1,1) ~= "#" and line:find("[^%" .. separator .. "% ]") then

            local mini_table = line:split(separator, true)
            return_table[mini_table[1]] = mini_table[2]

        end

    end

    return return_table

end

-- Format a table for display in minetest's debug.txt file
local function tprint(this_table, indent)

    -- Adapted from https://stackoverflow.com/questions/41942289/display-contents-of-tables-in-lua

    if not indent then indent = 0 end

    local toprint = "{\r\n"
    indent = indent + 4
    for k, v in pairs(this_table) do

        toprint = toprint .. string.rep(" ", indent)
        if (type(k) == "number") then
            toprint = toprint .. "[" .. k .. "] = "
        elseif (type(k) == "string") then
            toprint = toprint .. k ..  " = "
        end

        if (type(v) == "number") then
            toprint = toprint .. v .. ",\r\n"
        elseif (type(v) == "string") then
            toprint = toprint .. "\"" .. v .. "\",\r\n"
        elseif (type(v) == "table") then
            toprint = toprint .. tprint(v, indent) .. ",\r\n"
        else
            toprint = toprint .. "\"" .. tostring(v) .. "\",\r\n"
        end

    end

    toprint = toprint .. string.rep(" ", indent - 4) .. "}"
    return toprint

end

local function print_table(table_to_show, optional_title)

    -- Adapted from https://stackoverflow.com/questions/41942289/display-contents-of-tables-in-lua

    -- Basic checks
    if table_to_show == nil then

        show_error(S("Cannot print an unspecified table"))
        return

    elseif type(table_to_show) == "string" then

        show_error(S("Cannot print a string as a table"))
        return

    else

        -- Print the table
        local output = "\r\n"
        if optional_title then
            output = output .. optional_title .. "\r\n"
        end

        output = output .. tprint(table_to_show)

        minetest.log(output)

    end

end

-- Save a schematic as .mts
local function save_mts(schem_table, output_path)

    local mts_data = minetest.serialize_schematic(schem_table, "mts", {})
    local mts_output = io.open(output_path, "w")
    if not mts_data or not mts_output then

        show_error(S("Unable to save .mts file @1", output_path))
        return false

    else

        mts_output:write(mts_data)
        mts_output:flush()
        mts_output:close()
        return true

    end

end

-- Save a schematic as .lua
local function save_lua(schem_table, output_path)

    local lua_data = minetest.serialize_schematic(schem_table, "lua", {})
    local lua_output = io.open(output_path, "w")
    if not lua_data or not lua_output then

        show_error(S("Unable to save .lua file @1", output_path))
        return false

    else

        lua_output:write(lua_data)
        lua_output:flush()
        lua_output:close()

    end

end

---------------------------------------------------------------------------------------------------
-- Do the conversion
---------------------------------------------------------------------------------------------------

-- Read the file list, ignoring anything that isn't an .mts file
file_list = lines_from(mod_path .. "/files.txt", ".mts$")
-- Shortcut: if a file called "test.mts" exists, add it to the list
if file_exists(mod_path .. "/input/test.mts") then

    local match_flag = false
    for _, value in ipairs(file_list) do

        if value == "test.mts" then
            match_flag = true
            break
        end

    end

    if not match_flag then
        table.insert(file_list, "test.mts")
    end

end

show_info(S("Number of .mts files specified: @1", #file_list))

-- Read the conversion table. Every line in the CSV file should be in the form
--      original_node|replacement_node
-- For example
--      default:stone|mymod:rock
-- This produces a table in the form
--      convert_table["default:stone"] = "mymod:rock"
convert_table = read_csv(mod_path .. "/convert.csv")
-- (Every time a convertable not is found, remove it from this table)
check_table = table.copy(convert_table)

local count = 0
for k, v in pairs(convert_table) do
    count = count + 1
end

show_info(S("Number of convertable nodes specified: @1", tostring(count)))

-- Convert each schematic, one at a time
for _, local_path in ipairs(file_list) do

    local input_path = mod_path .. "/input/" .. local_path
    local output_path = mod_path .. "/output/" .. local_path
    local input_lua_path = mod_path .. "/output/" .. local_path .. ".input.lua"
    local output_lua_path = mod_path .. "/output/" .. local_path .. ".output.lua"

    if not file_exists(input_path) then

        show_info(S("Missing file: @1", input_path))
        error_count = error_count + 1

    else

        -- Read the original .mts file
        local schem_table = minetest.read_schematic(input_path, {})
        -- Write/display the original .mts file as lua, if required
        if write_converted_lua_flag then
            save_lua(schem_table, input_lua_path)
        end
        if show_original_lua_flag then
            print_table(schem_table, S("Contents of file @1", input_path))
        end

        -- Convert old nodes to new
        for i, mini_table in ipairs(schem_table.data) do

            if convert_table[mini_table.name] ~= nil then

                -- Convert this node
                mini_table.name = convert_table[mini_table.name]
                schem_table.data[i] = mini_table

                -- (Keep track of which convertable nodes have been found at least once)
                check_table[mini_table.name] = nil

                -- (Show converted nodes at the end, if required)
                if converted_table[mini_table.name] == nil then
                    converted_table[mini_table.name] = 1
                else
                    converted_table[mini_table.name] = converted_table[mini_table.name] + 1
                end

            else

                if not_converted_table[mini_table.name] == nil then
                    not_converted_table[mini_table.name] = 1
                else
                    not_converted_table[mini_table.name] = not_converted_table[mini_table.name] + 1
                end

            end

        end

        -- Save the converted .mts file
        if do_convert_flag then

            if not save_mts(schem_table, output_path) then
                error_count = error_count + 1
            else
                convert_count = convert_count + 1
            end

        end

        -- Write/display the converted .mts file as lua, if required
        if write_converted_lua_flag then
            save_lua(schem_table, output_lua_path)
        end
        if show_converted_lua_flag then
            print_table(schem_table, S("Contents of file @1", output_path))
        end

    end

end

-- Show the results
show_info(S("Number of .mts files converted: @1", convert_count))
show_info(S("Number of conversion errors: @1", error_count))

if show_summary_flag then

    if not next(converted_table) then

        show_info(S("Converted nodes: none"))

    else

        show_info(S("Converted nodes:"))

        table.sort(converted_table)
        for k, v in pairs(converted_table) do
            show_info("   " .. k .. ": " .. v)
        end

    end

    if not next(not_converted_table) then

        show_info(S("Non-converted nodes: none"))

    else

        show_info(S("Non-converted nodes:"))

        table.sort(not_converted_table)
        for k, v in pairs(not_converted_table) do
            show_info("   " .. k .. ": " .. v)
        end

    end

    if not next(check_table) then

        show_info(S("Convertable nodes not found: none"))

    else

        show_info(S("Convertable nodes not found:"))

        table.sort(check_table)
        for k, v in pairs(check_table) do
            show_info("   " .. k)
        end

    end

end