import argparse
import sys
import re
import os

from pathlib import Path
import shutil

# parse arguments
parser = argparse.ArgumentParser(description="parse netlist and pack all references to current working directory")
parser.add_argument("files", nargs="*", type=argparse.FileType("r"), default=sys.stdin)
parser.add_argument("-d", action="store_const", const=True, default=False, help="Dryrun")

args = parser.parse_args()

fileregex = re.compile(r"(?<!\w)file=\"(.*?)\"")
files = {}


# process all netlists
for file in args.files:
    location = Path(file.name)
    print(f"parsing {file.name}")

    content = file.read()

    with open(location.name, "w+") as outfile:
        last = 0

        # iterate over all matches
        for match in fileregex.finditer(content):
            start = match.start(1)
            end = match.end(1)
            
            path = Path(match.group(1))
            destpath = path

            # build the destination in the current folder
            # for the retrieved file reference
            if path.is_absolute():
                try:
                    destpath = path.relative_to(location.parent)
                except ValueError:
                    destpath = Path(*path.parts[-4:])
            else:
                path = Path.cwd() / path
                print(destpath.root)
                if destpath.parts[0] == "..":
                    destpath = Path(*destpath.parts[1:])
            
            # write the new path the new netlist file
            outfile.write(content[last:start])
            outfile.write(str(destpath))

            # remember file to be copied for later
            files[path] = destpath
            last = end

        outfile.write(content[last:])

# do dryrun if it is wanted
if args.d:
    for file in files:
        print(f"copy {file} -> {files[file]}")

    exit(0)


# copy all files found in netlist earlier
for file in files:
    src = Path(file)
    dst = Path(files[file])

    if not src.exists():
        print(f"src does not exist: {str(src)}")
        continue

    # create directory
    dst.parent.mkdir(parents=True, exist_ok=True)
    shutil.copyfile(src, dst)