#!/usr/bin/env python2

import argparse
import os
import shutil
import sys
import tempfile

from subprocess import check_call
from textwrap import dedent

CMAKE_INSTALL_LIBDIR_CHOICES = [None, 'lib', 'lib32', 'lib64']
PIGLIT_INSTALL_VERSION_CHOICES = [None, '1234']

DESCRIPTION = dedent("""\
    Test that the main piglit script, when installed, successfully imports
    the correct framework module.

    Failure modes
        1. The script fails to find any framework module and dies.
        2. The script finds and imports a framework module that belongs to
            a different Piglit.

    This test installs and verifies the piglit script with all combinations
    of the following CMake configuration variables:

        CMAKE_INSTALL_LIBDIR in {CMAKE_INSTALL_LIBDIR_CHOICES}
        PIGLIT_INSTALL_VERSION in {PIGLIT_INSTALL_VERSION_CHOICES}

    This test must be run from a git work tree. Due to the warned behavior below,
    the test will run only if given the '--force' option.

    WARNING
        - This test may remove any changes not committed to git, including ignored
            and untracked files.
    
        - This test may make changes to files in the git work tree (but it won't
            make any changes to the git directory itself).
    
        - This test will build and install Piglit multiple times to multiple
            temporary directories named 'tmp/piglit.XXXXXX'.  This test will not
            clean up its temporary directories. That's your responsibility.
    """.format(
        CMAKE_INSTALL_LIBDIR_CHOICES=CMAKE_INSTALL_LIBDIR_CHOICES,
        PIGLIT_INSTALL_VERSION_CHOICES=PIGLIT_INSTALL_VERSION_CHOICES))

def parse_args():
    parser = argparse.ArgumentParser()
    parser.formatter_class = argparse.RawDescriptionHelpFormatter
    parser.description = DESCRIPTION
    parser.add_argument('-f', '--force',
                        action='store_true',
                        help='really run the test')
    parser.add_argument('srcdir',
                        help='top of piglit source tree')
    return (parser.prog, parser.parse_args())

def main():
    prog, args = parse_args()
    if not args.force:
        parser.error("skipping test because '--force' option is missing")

    for piglit_install_version in PIGLIT_INSTALL_VERSION_CHOICES:
        for libdir in CMAKE_INSTALL_LIBDIR_CHOICES:
            test_once(args.srcdir, piglit_install_version, libdir)

    print('{0}: all tests passed'.format(prog))

def shell(command, cwd=None):
    check_call(command, shell=True, cwd=cwd)

def test_once(srcdir, piglit_install_version, libdir):
    test_result = False

    srcdir = os.path.abspath(srcdir)
    build_dir = tempfile.mkdtemp(prefix='piglit-build.')
    prefix = tempfile.mkdtemp(prefix='piglit-prefix.')

    def print_test_info():
        print('    srcdir: {0!r}'.format(srcdir))
        print('    libdir: {0!r}'.format(libdir))
        print('    piglit_install_version: {0!r}'.format(piglit_install_version))
        print('    build_dir: {0!r}'.format(build_dir))
        print('    prefix: {0!r}'.format(prefix))

    def print_test_result():
        if test_result:
            print('test passed:')
        else:
            print('test failed:')

        print_test_info()

    print('test start:')
    print_test_info()

    try:
        # Scrub the source tree.
        shell('git reset --hard', cwd=srcdir)
        shell('git clean -xfd', cwd=srcdir)

        # Make it build fast. We want to test the Python, not the C.
        shell("sed -i '/add_subdirectory/d' CMakeLists.txt", cwd=srcdir)

        cmake_args = [
            'cmake',
            '-GNinja',
            '-DCMAKE_INSTALL_PREFIX=' + prefix,
        ]

        if libdir is not None:
            cmake_args.append('-DCMAKE_INSTALL_LIBDIR=' + libdir)
        if piglit_install_version is not None:
            cmake_args.append('-DPIGLIT_INSTALL_VERSION=' + piglit_install_version)

        cmake_args.append(srcdir)

        check_call(cmake_args, cwd=build_dir)
        shell('ninja install', cwd=build_dir)

        # To prevent the false positive case when the installed script
        # accidentally imports the framework module located in git work tree,
        # execute the installed script with cwd=srcdir and fill the framework
        # module in srcdir with garbage. If the installed piglit script tries
        # to import it, then script will raise a Python exception and fail.
        shell("find framework -type f -exec echo GARBAGE '>' '{}' ';'", cwd=srcdir)

        # Append install version, if any, onto script name.
        script_name = 'piglit'
        if piglit_install_version is not None:
            script_name += '-' + piglit_install_version

        # Check script works when called with explicit filepath.
        bindir = os.path.join(prefix, 'bin')
        script_path = os.path.join(bindir, script_name)
        check_call([script_path, '--help'], cwd=srcdir)

        # Check script works when called through a PATH search.
        new_env = os.environ.copy()
        new_env['PATH'] = '{0}:{1}'.format(bindir, new_env['PATH'])
        check_call([script_name, '--help'], env=new_env, cwd=srcdir)

        test_result = True

    finally:
        print_test_result()
        shell('git reset --hard', cwd=srcdir)
        shutil.rmtree(build_dir)
        shutil.rmtree(prefix)

main()