#!/usr/bin/env python3

"""
This script generates a Windows manifest file and optionally a resource file to
determine whether a specified program requires UAC elevation
"""

import os
import argparse

DOMAIN_NAME='gnome'

def main():
    parser = argparse.ArgumentParser(
        description=__doc__)
    parser.add_argument('-p', '--package', required=True,
                        help='package name of the executable')
    parser.add_argument('-n', '--name', required=True,
                        help='name of executable')
    parser.add_argument('--pkg-version', required=True, dest='version',
                        help='version of package')
    parser.add_argument('--require-admin', action='store_true', dest='admin',
                        default=False,
                        help='require admin access to application')
    parser.add_argument('--input-resource-file', dest='resource',
                        default=None,
                        help='existing .rc file to embed UAC manifest (do not generate a new .rc file), must have included windows.h in it')
    parser.add_argument('--output-dir', dest='outdir',
                        default=None,
                        help='directory to output resulting files')
    args = parser.parse_args()

    if args.resource is not None:
        if not os.path.isfile(args.resource):
            raise FileNotFoundError("Specified resource file '%s' does not exist" % args.resource)

    generate_manifest(args.package, args.name, args.version, args.admin, args.outdir)
    write_rc_file(args.name, args.resource, args.outdir)

def generate_manifest(package, name, version, admin, outdir):
    if version.count('.') == 0:
        manifest_package_version = version + '.0.0.0'
    elif version.count('.') == 1:
        manifest_package_version = version + '.0.0'
    elif version.count('.') == 2:
        manifest_package_version = version + '.0'
    elif version.count('.') == 3:
        manifest_package_version = version
    else:
        parts = version.split('.')
        manifest_package_version = ''
        for x in (0, 1, 2, 3):
            if x == 0:
                manifest_package_version += parts[x]
            else:
                manifest_package_version += '.' + parts[x]

    if outdir is not None:
        output_file_base_name = os.path.join(outdir, name)
    else:
        output_file_base_name = name

    outfile = open(output_file_base_name + '.exe.manifest', 'w+')
    outfile.write('<?xml version="1.0" encoding="UTF-8" standalone="yes"?>\n')
    outfile.write('<assembly xmlns="urn:schemas-microsoft-com:asm.v1" manifestVersion="1.0">\n')
    outfile.write('  <assemblyIdentity version="%s"\n' % manifest_package_version)
    outfile.write('    processorArchitecture="*"\n')
    outfile.write('    name="%s.%s.%s.exe"\n' % (DOMAIN_NAME, package, name))
    outfile.write('    type="win32" />\n')
    outfile.write('  <trustInfo xmlns="urn:schemas-microsoft-com:asm.v3">\n')
    outfile.write('    <security>\n')
    outfile.write('      <requestedPrivileges>\n')
    outfile.write('        <requestedExecutionLevel\n')

    if admin:
        outfile.write('          level="requireAdministrator"\n')
    else:
        outfile.write('          level="asInvoker"\n')

    outfile.write('          uiAccess="false" />\n')
    outfile.write('      </requestedPrivileges>\n')
    outfile.write('    </security>\n')
    outfile.write('  </trustInfo>\n')
    outfile.write('</assembly>\n')
    outfile.close()

def write_rc_file(name, resource, outdir):
    if outdir is not None:
        output_file_base_name = os.path.join(outdir, name)
    else:
        output_file_base_name = name

    if resource is None:
        outfile = open(output_file_base_name + '.rc', 'w+')
        outfile.write('#define WIN32_LEAN_AND_MEAN\n')
        outfile.write('#include <windows.h>\n')
    else:
        if resource != output_file_base_name + '.rc':
            outfile = open(output_file_base_name + '.rc', 'w+')
        else:
            outfile = open(output_file_base_name + '.final.rc', 'w+')
        srcfile = open(resource, 'r')
        outfile.write(srcfile.read())
        srcfile.close()

    outfile.write('\n')
    outfile.write('CREATEPROCESS_MANIFEST_RESOURCE_ID RT_MANIFEST "%s.exe.manifest"' % name)
    outfile.close()

if __name__ == '__main__':
    main()