from __future__ import unicode_literals  # pragma: no cover
from __future__ import print_function  # pragma: no cover

# We have to use this entire file before we can turn coverage on, so we exclude
# it from coverage.  We still have tests, though!

import argparse  # pragma: no cover

try:  # pragma: no cover
    import configparser
except:  # pragma: no cover
    import ConfigParser as configparser

import coverage  # pragma: no cover

coverage_version = "Coverage {}".format(coverage.__version__)  # pragma: no cover

import copy  # pragma: no cover
import logging  # pragma: no cover
import os  # pragma: no cover
import sys  # pragma: no cover
import tempfile  # pragma: no cover
from textwrap import dedent  # pragma: no cover
import multiprocessing  # pragma: no cover

# Used for debugging output in cmdline, since we can't do debug output here.
files_loaded = []  # pragma: no cover

# Set the defaults in a re-usable way
default_args = argparse.Namespace(  # pragma: no cover
    targets=["."],  # Not in configs
    processes=multiprocessing.cpu_count(),
    initializer="",
    finalizer="",
    maxtasksperchild=None,
    termcolor=None,
    notermcolor=None,
    disable_windows=False,
    allow_stdout=False,
    quiet_stdout=False,
    no_skip_report=False,
    no_tracebacks=False,
    help=False,  # Not in configs
    version=False,
    logging=False,
    debug=0,
    verbose=1,
    disable_unidecode=False,
    failfast=False,
    config=None,  # Not in configs
    file_pattern="test*.py",
    test_pattern="*",
    junit_report="",
    run_coverage=False,
    cov_config_file=True,  # A string with a special boolean default
    quiet_coverage=False,
    clear_omit=False,
    omit_patterns=None,
    include_patterns=None,
    minimum_coverage=None,
    completion_file=False,
    completions=False,
    options=False,
    # These are not really options, they are added later for convenience
    parser=None,
    store_opt=None,
    # not implemented, but unittest stub in place
    warnings="",
)


class StoreOpt(object):  # pragma: no cover
    """
    Helper class for storing lists of the options themselves to hand out to the
    shell completion scripts.
    """

    def __init__(self):
        self.options = []
        self.actions = []

    def __call__(self, action):
        self.actions.append(action)
        self.options.extend(action.option_strings[0:2])


def parseArguments(argv=None):  # pragma: no cover
    """
    I parse arguments in sys.argv and return the args object.  The parser
    itself is available as args.parser.

    Adds the following members to args:
        parser    = the parser object
        store_opt = the StoreOpt object
    """
    store_opt = StoreOpt()
    parser = argparse.ArgumentParser(
        prog="green",
        usage="%(prog)s [options] [target [target2 ...]]",
        add_help=False,
        description=dedent(
            """
                Green is a clean, colorful, fast test runner for Python unit tests.
                """.rstrip()
        ),
        epilog=dedent(
            """
                ENABLING SHELL COMPLETION

                  To enable bash- or zsh-completion, add the line below to the end of your
                  .bashrc or .zshrc file (or equivalent config file):

                    which green >& /dev/null && source "$( green --completion-file )"

                  Warning!  Generating a completion list actually discovers and loads tests
                  -- this can be very slow if you run it in huge directories!

                SETUP.PY RUNNER

                  To run green as a setup.py command, simply add green to the 'setup_requires'
                  section in the setup.py file, and specify a target as the 'test_suite'
                  parameter if you do not want green to load all the tests:

                     setup(
                         setup_requires = ['green'],
                         install_requires = 'myproject.tests'
                     )

                  Then simply run green as any other setup.py command (it accepts the same
                  parameters as the 'green' executable):

                     python setup.py green
                     python setup.py green -r   # to run with coverage, etc.


                CONFIG FILES

                  For documentation on config files, please see
                  https://github.com/CleanCut/green#config-files
                """.rstrip()
        ),
        formatter_class=argparse.RawDescriptionHelpFormatter,
    )

    target_args = parser.add_argument_group("Target Specification")
    target_args.add_argument(
        "targets",
        action="store",
        nargs="*",
        metavar="target",
        help=(
            """Targets to test.  Any number of targets may be specified.  If
        blank, then discover all testcases in the current directory tree.  Can
        be a directory (or package), file (or module), or fully-qualified
        'dotted name' like proj.tests.test_things.TestStuff.  If a directory
        (or package) is specified, then we will attempt to discover all tests
        under the directory (even if the directory is a package and the tests
        would not be accessible through the package's scope).  In all other
        cases, only tests accessible from introspection of the object will
        be loaded."""
        ),
        default=argparse.SUPPRESS,
    )

    concurrency_args = parser.add_argument_group("Concurrency Options")
    store_opt(
        concurrency_args.add_argument(
            "-s",
            "--processes",
            action="store",
            type=int,
            metavar="NUM",
            help="Number of processes to use to run tests.  Note that your "
            "tests need to be written to avoid using the same resources (temp "
            "files, sockets, ports, etc.) for the multi-process mode to work "
            "well (--initializer and --finalizer can help provision "
            "per-process resources). Default is to run the same number of "
            "processes as your machine has logical CPUs. Note that for a "
            "small number of trivial tests, running everything in a single "
            "process may be faster than the overhead of initializing all the "
            "processes.",
            default=argparse.SUPPRESS,
        )
    )
    store_opt(
        concurrency_args.add_argument(
            "-i",
            "--initializer",
            action="store",
            metavar="DOTTED_FUNCTION",
            help="Python function to run inside of a single worker process "
            "before it starts running tests.  This is the way to provision "
            "external resources that each concurrent worker process needs to "
            "have exclusive access to. Specify the function in dotted "
            "notation in a way that will be importable from the location you "
            "are running green from.",
            default=argparse.SUPPRESS,
        )
    )
    store_opt(
        concurrency_args.add_argument(
            "-z",
            "--finalizer",
            action="store",
            metavar="DOTTED_FUNCTION",
            help="Same as --initializer, only run at the end of a worker "
            "process's lifetime.  Used to unprovision resources provisioned by "
            "the initializer.",
            default=argparse.SUPPRESS,
        )
    )
    store_opt(
        concurrency_args.add_argument(
            "-X",
            "--maxtasksperchild",
            action="store",
            metavar="NUM",
            type=int,
            help="Passed directly as the `maxtasksperchild` argument to an internal "
            '`multiprocessing.pool.Pool`. A "task" in this context usually corresponds to a test '
            "suite consisting of all the tests in a single file.  This option slows down testing, "
            "but has the benefit of guaranteeing a new Python process for each test suite.",
            default=argparse.SUPPRESS,
        )
    )

    format_args = parser.add_argument_group("Format Options")
    store_opt(
        format_args.add_argument(
            "-t",
            "--termcolor",
            action="store_true",
            help="Force terminal colors on.  Default is to autodetect.",
            default=argparse.SUPPRESS,
        )
    )
    store_opt(
        format_args.add_argument(
            "-T",
            "--notermcolor",
            action="store_true",
            help="Force terminal colors off.  Default is to autodetect.",
            default=argparse.SUPPRESS,
        )
    )
    store_opt(
        format_args.add_argument(
            "-W",
            "--disable-windows",
            action="store_true",
            help="Disable Windows support by turning off Colorama",
            default=argparse.SUPPRESS,
        )
    )

    out_args = parser.add_argument_group("Output Options")
    store_opt(
        out_args.add_argument(
            "-a",
            "--allow-stdout",
            action="store_true",
            help=(
                "Instead of capturing the stdout and stderr and presenting it "
                "in the summary of results, let it come through. Note that "
                "output from sources other than tests (like module/class setup "
                "or teardown) is never captured."
            ),
            default=argparse.SUPPRESS,
        )
    )
    store_opt(
        out_args.add_argument(
            "-q",
            "--quiet-stdout",
            action="store_true",
            help=(
                "Instead of capturing the stdout and stderr and presenting it "
                "in the summary of results, discard it completly for successful "
                "tests. --allow-stdout option overrides it."
            ),
            default=argparse.SUPPRESS,
        )
    )
    store_opt(
        out_args.add_argument(
            "-k",
            "--no-skip-report",
            action="store_true",
            help=(
                "Don't print the report of skipped tests "
                "after testing is done.  Skips will still show up in the progress "
                "report and summary count."
            ),
            default=argparse.SUPPRESS,
        )
    )
    store_opt(
        out_args.add_argument(
            "-e",
            "--no-tracebacks",
            action="store_true",
            help=("Don't print tracebacks for failures and " "errors."),
            default=argparse.SUPPRESS,
        )
    )
    store_opt(
        out_args.add_argument(
            "-h",
            "--help",
            action="store_true",
            help="Show this help message and exit.",
            default=argparse.SUPPRESS,
        )
    )
    store_opt(
        out_args.add_argument(
            "-V",
            "--version",
            action="store_true",
            help="Print the version of Green and Python and exit.",
            default=argparse.SUPPRESS,
        )
    )
    store_opt(
        out_args.add_argument(
            "-l",
            "--logging",
            action="store_true",
            help="Don't configure the root logger to redirect to /dev/null, "
            "enabling internal debugging output, as well as any output test (or "
            "tested) code may be sending via the root logger.",
            default=argparse.SUPPRESS,
        )
    )
    store_opt(
        out_args.add_argument(
            "-d",
            "--debug",
            action="count",
            help=(
                "Enable internal debugging statements.  Implies --logging.  Can "
                "be specified up to three times for more debug output."
            ),
            default=argparse.SUPPRESS,
        )
    )
    store_opt(
        out_args.add_argument(
            "-v",
            "--verbose",
            action="count",
            help=(
                "Verbose. Can be specified up to three times for more "
                "verbosity. Recommended levels are -v and -vv."
            ),
            default=argparse.SUPPRESS,
        )
    )
    store_opt(
        out_args.add_argument(
            "-U",
            "--disable-unidecode",
            action="store_true",
            help=(
                "Disable unidecode which converts test output from unicode to"
                "ascii by default on Windows to avoid hard-to-debug crashes."
            ),
            default=argparse.SUPPRESS,
        )
    )

    other_args = parser.add_argument_group("Other Options")
    store_opt(
        other_args.add_argument(
            "-f",
            "--failfast",
            action="store_true",
            help=("Stop execution at the first test that fails or errors."),
            default=argparse.SUPPRESS,
        )
    )
    store_opt(
        other_args.add_argument(
            "-c",
            "--config",
            action="store",
            metavar="FILE",
            help="Use this config file to override any values from "
            "the config file specified by environment variable GREEN_CONFIG, "
            "~/.green, and .green in the current working directory.",
            default=argparse.SUPPRESS,
        )
    )
    store_opt(
        other_args.add_argument(
            "-p",
            "--file-pattern",
            action="store",
            metavar="PATTERN",
            help="Pattern to match test files. Default is test*.py",
            default=argparse.SUPPRESS,
        )
    )
    store_opt(
        other_args.add_argument(
            "-n",
            "--test-pattern",
            action="store",
            metavar="PATTERN",
            help="Pattern to match test method names after "
            "'test'.  Default is '*', meaning match methods named 'test*'.",
            default=argparse.SUPPRESS,
        )
    )
    store_opt(
        other_args.add_argument(
            "-j",
            "--junit-report",
            action="store",
            metavar="FILENAME",
            help=("Generate a JUnit XML report."),
            default=argparse.SUPPRESS,
        )
    )

    cov_args = parser.add_argument_group(
        "Coverage Options ({})".format(coverage_version)
    )
    store_opt(
        cov_args.add_argument(
            "-r",
            "--run-coverage",
            action="store_true",
            help=("Produce coverage output."),
            default=argparse.SUPPRESS,
        )
    )
    store_opt(
        cov_args.add_argument(
            "-g",
            "--cov-config-file",
            action="store",
            metavar="FILE",
            help=(
                "Specify a coverage config file. "
                "Implies --run-coverage See the coverage documentation "
                "at https://coverage.readthedocs.io/en/v4.5.x/config.html "
                "for coverage config file syntax. The [run] and [report] sections "
                "are most relevant."
            ),
            default=argparse.SUPPRESS,
        )
    ),
    store_opt(
        cov_args.add_argument(
            "-R",
            "--quiet-coverage",
            action="store_true",
            help=(
                "Do not print coverage report to stdout (coverage files will "
                "still be created). Implies --run-coverage"
            ),
            default=argparse.SUPPRESS,
        )
    )
    store_opt(
        cov_args.add_argument(
            "-O",
            "--clear-omit",
            action="store_true",
            help=(
                "Green tries really hard to set up a good list of patterns of "
                "files to omit from coverage reports.  If the default list "
                "catches files that you DO want to cover you can specify this "
                "flag to leave the default list empty to start with.  You can "
                "then add patterns back in with --omit-patterns. The default "
                "list is something like '*/test*,*/mock*,*(temp dir)*,*(python "
                "system packages)*' -- only longer."
            ),
            default=argparse.SUPPRESS,
        )
    )
    store_opt(
        cov_args.add_argument(
            "-u",
            "--include-patterns",
            action="store",
            metavar="PATTERN",
            help=(
                "Comma-separated file-patterns to include in coverage.  This "
                "implies that anything that does not match the include pattern is "
                "omitted from coverage reporting."
            ),
            default=argparse.SUPPRESS,
        )
    )
    store_opt(
        cov_args.add_argument(
            "-o",
            "--omit-patterns",
            action="store",
            metavar="PATTERN",
            help=(
                "Comma-separated file-patterns to omit from coverage.  For "
                "example, if coverage reported a file mypackage/foo/bar you could "
                "omit it from coverage with 'mypackage*', '*/foo/*', or '*bar'"
            ),
            default=argparse.SUPPRESS,
        )
    )
    store_opt(
        cov_args.add_argument(
            "-m",
            "--minimum-coverage",
            action="store",
            metavar="X",
            type=int,
            help=(
                "Integer. A minimum coverage value.  If "
                "not met, then we will print a message and exit with a nonzero "
                "status. Implies --run-coverage"
            ),
            default=argparse.SUPPRESS,
        )
    )

    integration_args = parser.add_argument_group("Integration Options")
    store_opt(
        integration_args.add_argument(
            "--completion-file",
            action="store_true",
            help=(
                "Location of the bash- and zsh-completion "
                "file.  To enable bash- or zsh-completion, see ENABLING SHELL "
                "COMPLETION below."
            ),
            default=argparse.SUPPRESS,
        )
    )
    store_opt(
        integration_args.add_argument(
            "--completions",
            action="store_true",
            help=(
                "Output possible completions of the given target.  Used by "
                "bash- and zsh-completion."
            ),
            default=argparse.SUPPRESS,
        )
    )
    store_opt(
        integration_args.add_argument(
            "--options",
            action="store_true",
            help="Output all options.  Used by bash- and zsh-completion.",
            default=argparse.SUPPRESS,
        )
    )

    args = parser.parse_args(argv)

    # Add additional members
    args.parser = parser
    args.store_opt = store_opt

    return args


class ConfigFile(object):  # pragma: no cover
    """
    Filehandle wrapper that adds a "[green]" section to the start of a config
    file so that users don't actually have to manually add a [green] section.

    Works with configparser versions from both Python 2 and 3
    """

    def __init__(self, filepath):
        self.first = True
        with open(filepath) as f:
            self.lines = f.readlines()

    # Python 2.7 (Older dot versions)
    def readline(self):
        try:
            return self.__next__()
        except StopIteration:
            return ""

    # Python 2.7 (Newer dot versions)
    def next(self):
        return self.__next__()

    # Python 3
    def __iter__(self):
        return self

    def __next__(self):
        if self.first:
            self.first = False
            return "[green]\n"
        if self.lines:
            return self.lines.pop(0)
        raise StopIteration


# Since this must be imported before coverage is started, we get erroneous
# reports of not covering this function during our internal coverage tests.
def getConfig(filepath=None):  # pragma: no cover
    """
    Get the Green config file settings.

    All available config files are read.  If settings are in multiple configs,
    the last value encountered wins.  Values specified on the command-line take
    precedence over all config file settings.

    Returns: A ConfigParser object.
    """
    parser = configparser.ConfigParser()

    filepaths = []
    # Lowest priority goes first in the list
    home = os.getenv("HOME")
    if home:
        default_filepath = os.path.join(home, ".green")
        if os.path.isfile(default_filepath):
            filepaths.append(default_filepath)

    # Low priority
    env_filepath = os.getenv("GREEN_CONFIG")
    if env_filepath and os.path.isfile(env_filepath):
        filepaths.append(env_filepath)

    # Medium priority
    for cfg_file in ("setup.cfg", ".green"):
        cwd_filepath = os.path.join(os.getcwd(), cfg_file)
        if os.path.isfile(cwd_filepath):
            filepaths.append(cwd_filepath)

    # High priority
    if filepath and os.path.isfile(filepath):
        filepaths.append(filepath)

    if filepaths:
        global files_loaded
        files_loaded = filepaths
        # Python 3 has parser.read_file(iterator) while Python2 has
        # parser.readfp(obj_with_readline)
        read_func = getattr(parser, "read_file", getattr(parser, "readfp"))
        for filepath in filepaths:
            # Users are expected to put a [green] section
            # only if they use setup.cfg
            if filepath.endswith("setup.cfg"):
                with open(filepath) as f:
                    read_func(f)
            else:
                read_func(ConfigFile(filepath))

    return parser


# Since this must be imported before coverage is started, we get erroneous
# reports of not covering this function during our internal coverage tests.
def mergeConfig(args, testing=False):  # pragma: no cover
    """
    I take in a namespace created by the ArgumentParser in cmdline.main() and
    merge in options from configuration files.  The config items only replace
    argument items that are set to default value.

    Returns: I return a new argparse.Namespace, adding members:
        shouldExit       = default False
        exitCode         = default 0
        include patterns = include-patterns setting converted to list.
        omit_patterns    = omit-patterns settings converted to list and
                           extended, taking clear-omit into account.
        cov              = coverage object default None
    """
    config = getConfig(getattr(args, "config", default_args.config))
    new_args = copy.deepcopy(default_args)  # Default by default!

    for name, default_value in dict(default_args._get_kwargs()).items():
        # Config options overwrite default options
        config_getter = None
        if name in [
            "termcolor",
            "notermcolor",
            "allow_stdout",
            "quiet_stdout",
            "help",
            "logging",
            "version",
            "disable_unidecode",
            "failfast",
            "run_coverage",
            "options",
            "completions",
            "completion_file",
            "clear_omit",
            "no_skip_report",
            "no_tracebacks",
            "disable_windows",
            "quiet_coverage",
        ]:
            config_getter = config.getboolean
        elif name in [
            "processes",
            "debug",
            "verbose",
            "minimum_coverage",
            "maxtasksperchild",
        ]:
            config_getter = config.getint
        elif name in [
            "file_pattern",
            "finalizer",
            "initializer",
            "cov_config_file",
            "include_patterns",
            "omit_patterns",
            "warnings",
            "test_pattern",
            "junit_report",
        ]:
            config_getter = config.get
        elif name in ["targets", "help", "config"]:
            pass  # Some options only make sense coming on the command-line.
        elif name in ["store_opt", "parser"]:
            pass  # These are convenience objects, not actual settings
        else:
            raise NotImplementedError(name)

        if config_getter:
            try:
                config_value = config_getter("green", name.replace("_", "-"))
                setattr(new_args, name, config_value)
            except (configparser.NoSectionError, configparser.NoOptionError):
                pass

        # Command-line values overwrite defaults and config values when
        # specified
        args_value = getattr(args, name, "unspecified")
        if args_value != "unspecified":
            setattr(new_args, name, args_value)

    new_args.shouldExit = False
    new_args.exitCode = 0
    new_args.cov = None

    # Help?
    if new_args.help:  # pragma: no cover
        new_args.parser.print_help()
        new_args.shouldExit = True
        return new_args

    # Did we just print the version?
    if new_args.version:
        from green.version import pretty_version

        sys.stdout.write(pretty_version() + "\n")
        new_args.shouldExit = True
        return new_args

    # Handle logging options
    if new_args.debug:
        logging.basicConfig(
            level=logging.DEBUG,
            format="%(asctime)s %(levelname)9s %(message)s",
            datefmt="%Y-%m-%d %H:%M:%S",
        )
    elif not new_args.logging:
        logging.basicConfig(filename=os.devnull)

    # Disable termcolor?
    if new_args.notermcolor:
        new_args.termcolor = False

    # Coverage.  We must enable it here because we cannot cover module-level
    # code after it is imported, and this is the earliest place we can turn on
    # coverage.
    omit_patterns = [
        "*/argparse*",
        "*/colorama*",
        "*/django/*",
        "*/distutils*",  # Gets pulled in on Travis-CI CPython
        "*/extras*",  # pulled in by testtools
        "*/linecache2*",  # pulled in by testtools
        "*/mimeparse*",  # pulled in by testtools
        "*/mock*",
        "*/pbr*",  # pulled in by testtools
        "*/pkg_resources*",  # pulled in by django
        "*/pypy*",
        "*/pytz*",  # pulled in by django
        "*/six*",  # pulled in by testtools
        "*/termstyle*",
        "*/test*",
        "*/traceback2*",  # pulled in by testtools
        "*/unittest2*",  # pulled in by testtools
        "*Python.framework*",  # OS X system python
        "*site-packages*",  # System python for other OS's
        "*/dist-packages*",  # Resolves issue #259
        tempfile.gettempdir() + "*",
    ]
    if new_args.clear_omit:
        omit_patterns = []

    if new_args.omit_patterns:
        omit_patterns.extend(new_args.omit_patterns.split(","))
    new_args.omit_patterns = omit_patterns

    if new_args.include_patterns:
        new_args.include_patterns = new_args.include_patterns.split(",")
    else:
        new_args.include_patterns = []

    if new_args.quiet_coverage or (type(new_args.cov_config_file) == str):
        new_args.run_coverage = True

    if new_args.minimum_coverage != None:
        new_args.run_coverage = True

    if new_args.run_coverage:
        if not testing:
            cov = coverage.coverage(
                data_file=".coverage",
                omit=omit_patterns,
                include=new_args.include_patterns,
                config_file=new_args.cov_config_file,
            )
            cov.start()
        new_args.cov = cov

    return new_args
