""" version info, help messages, tracing configuration.  """
from __future__ import absolute_import, division, print_function

import py
import pytest
from _pytest.config import PrintHelp
import os
import sys
from argparse import Action


class HelpAction(Action):
    """This is an argparse Action that will raise an exception in
    order to skip the rest of the argument parsing when --help is passed.
    This prevents argparse from quitting due to missing required arguments
    when any are defined, for example by ``pytest_addoption``.
    This is similar to the way that the builtin argparse --help option is
    implemented by raising SystemExit.
    """

    def __init__(self, option_strings, dest=None, default=False, help=None):
        super(HelpAction, self).__init__(
            option_strings=option_strings,
            dest=dest,
            const=True,
            default=default,
            nargs=0,
            help=help,
        )

    def __call__(self, parser, namespace, values, option_string=None):
        setattr(namespace, self.dest, self.const)

        # We should only skip the rest of the parsing after preparse is done
        if getattr(parser._parser, "after_preparse", False):
            raise PrintHelp


def pytest_addoption(parser):
    group = parser.getgroup("debugconfig")
    group.addoption(
        "--version",
        action="store_true",
        help="display pytest lib version and import information.",
    )
    group._addoption(
        "-h",
        "--help",
        action=HelpAction,
        dest="help",
        help="show help message and configuration info",
    )
    group._addoption(
        "-p",
        action="append",
        dest="plugins",
        default=[],
        metavar="name",
        help="early-load given plugin (multi-allowed). "
        "To avoid loading of plugins, use the `no:` prefix, e.g. "
        "`no:doctest`.",
    )
    group.addoption(
        "--traceconfig",
        "--trace-config",
        action="store_true",
        default=False,
        help="trace considerations of conftest.py files.",
    ),
    group.addoption(
        "--debug",
        action="store_true",
        dest="debug",
        default=False,
        help="store internal tracing debug information in 'pytestdebug.log'.",
    )
    group._addoption(
        "-o",
        "--override-ini",
        dest="override_ini",
        action="append",
        help='override ini option with "option=value" style, e.g. `-o xfail_strict=True -o cache_dir=cache`.',
    )


@pytest.hookimpl(hookwrapper=True)
def pytest_cmdline_parse():
    outcome = yield
    config = outcome.get_result()
    if config.option.debug:
        path = os.path.abspath("pytestdebug.log")
        debugfile = open(path, "w")
        debugfile.write(
            "versions pytest-%s, py-%s, "
            "python-%s\ncwd=%s\nargs=%s\n\n"
            % (
                pytest.__version__,
                py.__version__,
                ".".join(map(str, sys.version_info)),
                os.getcwd(),
                config._origargs,
            )
        )
        config.trace.root.setwriter(debugfile.write)
        undo_tracing = config.pluginmanager.enable_tracing()
        sys.stderr.write("writing pytestdebug information to %s\n" % path)

        def unset_tracing():
            debugfile.close()
            sys.stderr.write("wrote pytestdebug information to %s\n" % debugfile.name)
            config.trace.root.setwriter(None)
            undo_tracing()

        config.add_cleanup(unset_tracing)


def pytest_cmdline_main(config):
    if config.option.version:
        p = py.path.local(pytest.__file__)
        sys.stderr.write(
            "This is pytest version %s, imported from %s\n" % (pytest.__version__, p)
        )
        plugininfo = getpluginversioninfo(config)
        if plugininfo:
            for line in plugininfo:
                sys.stderr.write(line + "\n")
        return 0
    elif config.option.help:
        config._do_configure()
        showhelp(config)
        config._ensure_unconfigure()
        return 0


def showhelp(config):
    reporter = config.pluginmanager.get_plugin("terminalreporter")
    tw = reporter._tw
    tw.write(config._parser.optparser.format_help())
    tw.line()
    tw.line()
    tw.line(
        "[pytest] ini-options in the first " "pytest.ini|tox.ini|setup.cfg file found:"
    )
    tw.line()

    for name in config._parser._ininames:
        help, type, default = config._parser._inidict[name]
        if type is None:
            type = "string"
        spec = "%s (%s)" % (name, type)
        line = "  %-24s %s" % (spec, help)
        tw.line(line[:tw.fullwidth])

    tw.line()
    tw.line("environment variables:")
    vars = [
        ("PYTEST_ADDOPTS", "extra command line options"),
        ("PYTEST_PLUGINS", "comma-separated plugins to load during startup"),
        ("PYTEST_DEBUG", "set to enable debug tracing of pytest's internals"),
    ]
    for name, help in vars:
        tw.line("  %-24s %s" % (name, help))
    tw.line()
    tw.line()

    tw.line("to see available markers type: pytest --markers")
    tw.line("to see available fixtures type: pytest --fixtures")
    tw.line(
        "(shown according to specified file_or_dir or current dir "
        "if not specified; fixtures with leading '_' are only shown "
        "with the '-v' option"
    )

    for warningreport in reporter.stats.get("warnings", []):
        tw.line("warning : " + warningreport.message, red=True)
    return


conftest_options = [("pytest_plugins", "list of plugin names to load")]


def getpluginversioninfo(config):
    lines = []
    plugininfo = config.pluginmanager.list_plugin_distinfo()
    if plugininfo:
        lines.append("setuptools registered plugins:")
        for plugin, dist in plugininfo:
            loc = getattr(plugin, "__file__", repr(plugin))
            content = "%s-%s at %s" % (dist.project_name, dist.version, loc)
            lines.append("  " + content)
    return lines


def pytest_report_header(config):
    lines = []
    if config.option.debug or config.option.traceconfig:
        lines.append("using: pytest-%s pylib-%s" % (pytest.__version__, py.__version__))

        verinfo = getpluginversioninfo(config)
        if verinfo:
            lines.extend(verinfo)

    if config.option.traceconfig:
        lines.append("active plugins:")
        items = config.pluginmanager.list_name_plugin()
        for name, plugin in items:
            if hasattr(plugin, "__file__"):
                r = plugin.__file__
            else:
                r = repr(plugin)
            lines.append("    %-20s: %s" % (name, r))
    return lines
