volupack.py

#!/usr/bin/env python
"""
volupack - Packs multiple Lua files for Vendetta Online into a single file.

Given the following layout:

main.lua:
    mylib = {}
    dofile("file1.lua")
    dofile("file2.lua")

file1.lua:
    mylib.foo = {}
    function mylib.foo.bar ... end

file2.lua
    mylib.bar = {}
    mylib.bar.FOO = 2

calling volupack with the following parameters:

    volupack mylib main.lua mylib_packed.lua

results in a file `mylib_packed.lua` with the following contents:

    local mylib = {}

    mylib.foo = {}
    function mylib.foo.bar ... end

    mylib.bar = {}
    mylib.bar.FOO = 2

    return mylib

The library can now be used by plugins like so:

    local mylib = dofile("mylib_packed.lua")
    print(mylib.bar.FOO)


.. moduleauthor:: Fabian Hirschmann <fabian@hirschm.net>
"""
from __future__ import print_function
import re
import os
import argparse


def walk(output, path, ns):
    output.write("-- %s starts.%s" % (path, os.linesep))
    with open(path) as f:
        lineno = 1
        output.write("\n")
        for line in f.readlines():
            line = line.replace("\r\n", "").replace("\n", "") + os.linesep
            if "dofile" in line:
                match = re.match("dofile\(['\"]*(.+?)['\"]\)", line)
                if not match:
                    print("WARNING: Could not include file in %s:%s:\n\t%s" % (
                          path, lineno, line))
                    output.write(line)
                    continue
                walk(output, match.group(1), ns)
            else:
                match = False

                if line.startswith("declare("):
                    # replace: declare(ns, ...)
                    match = re.match("declare\(['\"]*%s['\"], (.+?)\)" % ns, line)
                    value = match.group(1)
                else:
                    # replace: ns = ...
                    match = re.match("%s\s=\s(.+)" % ns, line)
                    if match:
                        print(line)

                if match:
                    print("WARNING: Replaced global declare in %s:%s" % (
                        path, lineno))
                    print("< %s" % line.strip())
                    newline = "local %s = %s" % (ns, "{}" if "or {}" in value else value)
                    print("> %s" % newline)
                    output.write(newline)
                else:
                    output.write(line)
            lineno += 1
    output.write("-- %s ends.%s" % (path, os.linesep))


if __name__ == "__main__":
    parser = argparse.ArgumentParser(description=os.linesep.join(__doc__.split("\n")[:-2]),
                                     formatter_class=argparse.RawTextHelpFormatter)
    parser.add_argument("namespace", type=str, help="global namespace to remove")
    parser.add_argument("main", type=str, help="file to start with")
    parser.add_argument("output", type=str, help="output file")

    args = parser.parse_args()
    with open(args.output, "w") as output:
        output.write("-- packed using volupack." + os.linesep)
        walk(output, args.main, args.namespace)
        output.write("return " + args.namespace + os.linesep)