"""Helper for building, testing, and linting coverage.py.

To get portability, all these operations are written in Python here instead
of in shell scripts, batch files, or Makefiles.

"""

import fnmatch
import glob
import os
import platform
import sys
import zipfile


def do_remove_extension(args):
    """Remove the compiled C extension, no matter what its name."""

    so_patterns = """
        tracer.so
        tracer.*.so
        tracer.pyd
        """.split()

    for pattern in so_patterns:
        pattern = os.path.join("coverage", pattern)
        for filename in glob.glob(pattern):
            try:
                os.remove(filename)
            except OSError:
                pass

def do_test_with_tracer(args):
    """Run nosetests with a particular tracer."""
    import nose.core
    tracer = args[0]
    if tracer == "py":
        label = "with Python tracer"
    else:
        label = "with C tracer"
        if os.environ.get("COVERAGE_NO_EXTENSION"):
            print("Skipping tests, no C extension in this environment")
            return
    print_banner(label)
    os.environ["COVERAGE_TEST_TRACER"] = tracer
    nose_args = ["nosetests"] + args[1:]
    nose.core.main(argv=nose_args)

def do_zip_mods(args):
    """Build the zipmods.zip file."""
    zf = zipfile.ZipFile("test/zipmods.zip", "w")
    zf.write("test/covmodzip1.py", "covmodzip1.py")
    zf.close()

def do_check_eol(args):
    """Check files for incorrect newlines and trailing whitespace."""

    ignore_dirs = [
        '.svn', '.hg', '.tox', '.tox_kits', 'coverage.egg-info',
        '_build',
        ]
    checked = set([])

    def check_file(fname, crlf=True, trail_white=True):
        fname = os.path.relpath(fname)
        if fname in checked:
            return
        checked.add(fname)

        line = None
        for n, line in enumerate(open(fname, "rb")):
            if crlf:
                if "\r" in line:
                    print("%s@%d: CR found" % (fname, n+1))
                    return
            if trail_white:
                line = line[:-1]
                if not crlf:
                    line = line.rstrip('\r')
                if line.rstrip() != line:
                    print("%s@%d: trailing whitespace found" % (fname, n+1))
                    return

        if line is not None and not line.strip():
            print("%s: final blank line" % (fname,))

    def check_files(root, patterns, **kwargs):
        for root, dirs, files in os.walk(root):
            for f in files:
                fname = os.path.join(root, f)
                for p in patterns:
                    if fnmatch.fnmatch(fname, p):
                        check_file(fname, **kwargs)
                        break
            for dir_name in ignore_dirs:
                if dir_name in dirs:
                    dirs.remove(dir_name)

    check_files("coverage", ["*.py", "*.c"])
    check_files("coverage/htmlfiles", ["*.html", "*.css", "*.js"])
    check_file("test/farm/html/src/bom.py", crlf=False)
    check_files("test", ["*.py"])
    check_files("test", ["*,cover"], trail_white=False)
    check_files("test/js", ["*.js", "*.html"])
    check_file("setup.py")
    check_files("doc", ["*.rst"])
    check_files(".", ["*.txt"])


def print_banner(label):
    """Print the version of Python."""
    try:
        impl = platform.python_implementation()
    except AttributeError:
        impl = "Python"

    version = platform.python_version()

    if '__pypy__' in sys.builtin_module_names:
        pypy_version = ".".join([str(v) for v in sys.pypy_version_info])
        version += " (pypy %s)" % pypy_version

    print('=== %s %s %s (%s) ===' % (impl, version, label, sys.executable))


def main(args):
    handler = globals().get('do_'+args[0])
    if handler is None:
        print("*** No handler for %r" % args[0])
        return 1
    return handler(args[1:])

if __name__ == '__main__':
    sys.exit(main(sys.argv[1:]))