#!/usr/bin/env python3
# Copyright 2011 The Chromium Authors
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.

"""Rewrites paths in -I, -L and other option to be relative to a sysroot."""

import sys
import os
import optparse

REWRITE_PREFIX = [
    '-I',
    '-idirafter',
    '-imacros',
    '-imultilib',
    '-include',
    '-iprefix',
    '-iquote',
    '-isystem',
    '-L',
]


def RewritePath(path, opts):
    """Rewrites a path by stripping the prefix and prepending the sysroot."""
    sysroot = opts.sysroot
    prefix = opts.strip_prefix
    if os.path.isabs(path) and not path.startswith(sysroot):
        if path.startswith(prefix):
            path = path[len(prefix) :]
        path = path.lstrip('/')
        return os.path.join(sysroot, path)
    else:
        return path


def RewriteLine(line, opts):
    """Rewrites all the paths in recognized options."""
    args = line.split()
    count = len(args)
    i = 0
    while i < count:
        for prefix in REWRITE_PREFIX:
            # The option can be either in the form "-I /path/to/dir" or
            # "-I/path/to/dir" so handle both.
            if args[i] == prefix:
                i += 1
                try:
                    args[i] = RewritePath(args[i], opts)
                except IndexError:
                    sys.stderr.write('Missing argument following %s\n' % prefix)
                    break
            elif args[i].startswith(prefix):
                args[i] = prefix + RewritePath(args[i][len(prefix) :], opts)
        i += 1

    return ' '.join(args)


def main(argv):
    parser = optparse.OptionParser()
    parser.add_option('-s', '--sysroot', default='/', help='sysroot to prepend')
    parser.add_option(
        '-p', '--strip-prefix', default='', help='prefix to strip'
    )
    opts, args = parser.parse_args(argv[1:])

    for line in sys.stdin.readlines():
        line = RewriteLine(line.strip(), opts)
        print(line)
    return 0


if __name__ == '__main__':
    sys.exit(main(sys.argv))