# -*- coding: utf-8 -*-
"""IPython Test Process Controller

This module runs one or more subprocesses which will actually run the IPython
test suite.

"""

# Copyright (c) IPython Development Team.
# Distributed under the terms of the Modified BSD License.


import argparse
import multiprocessing.pool
import os
import stat
import shutil
import signal
import sys
import subprocess
import time

from .iptest import (
    have, test_group_names as py_test_group_names, test_sections, StreamCapturer,
)
from IPython.utils.path import compress_user
from IPython.utils.py3compat import decode
from IPython.utils.sysinfo import get_sys_info
from IPython.utils.tempdir import TemporaryDirectory

class TestController:
    """Run tests in a subprocess
    """
    #: str, IPython test suite to be executed.
    section = None
    #: list, command line arguments to be executed
    cmd = None
    #: dict, extra environment variables to set for the subprocess
    env = None
    #: list, TemporaryDirectory instances to clear up when the process finishes
    dirs = None
    #: subprocess.Popen instance
    process = None
    #: str, process stdout+stderr
    stdout = None

    def __init__(self):
        self.cmd = []
        self.env = {}
        self.dirs = []

    def setUp(self):
        """Create temporary directories etc.
        
        This is only called when we know the test group will be run. Things
        created here may be cleaned up by self.cleanup().
        """
        pass

    def launch(self, buffer_output=False, capture_output=False):
        # print('*** ENV:', self.env)  # dbg
        # print('*** CMD:', self.cmd)  # dbg
        env = os.environ.copy()
        env.update(self.env)
        if buffer_output:
            capture_output = True
        self.stdout_capturer = c = StreamCapturer(echo=not buffer_output)
        c.start()
        stdout = c.writefd if capture_output else None
        stderr = subprocess.STDOUT if capture_output else None
        self.process = subprocess.Popen(self.cmd, stdout=stdout,
                stderr=stderr, env=env)

    def wait(self):
        self.process.wait()
        self.stdout_capturer.halt()
        self.stdout = self.stdout_capturer.get_buffer()
        return self.process.returncode

    def cleanup_process(self):
        """Cleanup on exit by killing any leftover processes."""
        subp = self.process
        if subp is None or (subp.poll() is not None):
            return  # Process doesn't exist, or is already dead.

        try:
            print('Cleaning up stale PID: %d' % subp.pid)
            subp.kill()
        except: # (OSError, WindowsError) ?
            # This is just a best effort, if we fail or the process was
            # really gone, ignore it.
            pass
        else:
            for i in range(10):
                if subp.poll() is None:
                    time.sleep(0.1)
                else:
                    break

        if subp.poll() is None:
            # The process did not die...
            print('... failed. Manual cleanup may be required.')

    def cleanup(self):
        "Kill process if it's still alive, and clean up temporary directories"
        self.cleanup_process()
        for td in self.dirs:
            td.cleanup()

    __del__ = cleanup


class PyTestController(TestController):
    """Run Python tests using IPython.testing.iptest"""
    #: str, Python command to execute in subprocess
    pycmd = None

    def __init__(self, section, options):
        """Create new test runner."""
        TestController.__init__(self)
        self.section = section
        # pycmd is put into cmd[2] in PyTestController.launch()
        self.cmd = [sys.executable, '-c', None, section]
        self.pycmd = "from IPython.testing.iptest import run_iptest; run_iptest()"
        self.options = options

    def setup(self):
        ipydir = TemporaryDirectory()
        self.dirs.append(ipydir)
        self.env['IPYTHONDIR'] = ipydir.name
        self.workingdir = workingdir = TemporaryDirectory()
        self.dirs.append(workingdir)
        self.env['IPTEST_WORKING_DIR'] = workingdir.name
        # This means we won't get odd effects from our own matplotlib config
        self.env['MPLCONFIGDIR'] = workingdir.name
        # For security reasons (http://bugs.python.org/issue16202), use
        # a temporary directory to which other users have no access.
        self.env['TMPDIR'] = workingdir.name

        # Add a non-accessible directory to PATH (see gh-7053)
        noaccess = os.path.join(self.workingdir.name, "_no_access_")
        self.noaccess = noaccess
        os.mkdir(noaccess, 0)

        PATH = os.environ.get('PATH', '')
        if PATH:
            PATH = noaccess + os.pathsep + PATH
        else:
            PATH = noaccess
        self.env['PATH'] = PATH

        # From options:
        if self.options.xunit:
            self.add_xunit()
        if self.options.coverage:
            self.add_coverage()
        self.env['IPTEST_SUBPROC_STREAMS'] = self.options.subproc_streams
        self.cmd.extend(self.options.extra_args)

    def cleanup(self):
        """
        Make the non-accessible directory created in setup() accessible
        again, otherwise deleting the workingdir will fail.
        """
        os.chmod(self.noaccess, stat.S_IRWXU)
        TestController.cleanup(self)

    @property
    def will_run(self):
        try:
            return test_sections[self.section].will_run
        except KeyError:
            return True

    def add_xunit(self):
        xunit_file = os.path.abspath(self.section + '.xunit.xml')
        self.cmd.extend(['--with-xunit', '--xunit-file', xunit_file])

    def add_coverage(self):
        try:
            sources = test_sections[self.section].includes
        except KeyError:
            sources = ['IPython']

        coverage_rc = ("[run]\n"
                       "data_file = {data_file}\n"
                       "source =\n"
                       "  {source}\n"
                      ).format(data_file=os.path.abspath('.coverage.'+self.section),
                               source="\n  ".join(sources))
        config_file = os.path.join(self.workingdir.name, '.coveragerc')
        with open(config_file, 'w') as f:
            f.write(coverage_rc)

        self.env['COVERAGE_PROCESS_START'] = config_file
        self.pycmd = "import coverage; coverage.process_startup(); " + self.pycmd

    def launch(self, buffer_output=False):
        self.cmd[2] = self.pycmd
        super(PyTestController, self).launch(buffer_output=buffer_output)


def prepare_controllers(options):
    """Returns two lists of TestController instances, those to run, and those
    not to run."""
    testgroups = options.testgroups
    if not testgroups:
        testgroups = py_test_group_names

    controllers = [PyTestController(name, options) for name in testgroups]

    to_run = [c for c in controllers if c.will_run]
    not_run = [c for c in controllers if not c.will_run]
    return to_run, not_run

def do_run(controller, buffer_output=True):
    """Setup and run a test controller.
    
    If buffer_output is True, no output is displayed, to avoid it appearing
    interleaved. In this case, the caller is responsible for displaying test
    output on failure.
    
    Returns
    -------
    controller : TestController
      The same controller as passed in, as a convenience for using map() type
      APIs.
    exitcode : int
      The exit code of the test subprocess. Non-zero indicates failure.
    """
    try:
        try:
            controller.setup()
            controller.launch(buffer_output=buffer_output)
        except Exception:
            import traceback
            traceback.print_exc()
            return controller, 1  # signal failure

        exitcode = controller.wait()
        return controller, exitcode

    except KeyboardInterrupt:
        return controller, -signal.SIGINT
    finally:
        controller.cleanup()

def report():
    """Return a string with a summary report of test-related variables."""
    inf = get_sys_info()
    out = []
    def _add(name, value):
        out.append((name, value))

    _add('IPython version', inf['ipython_version'])
    _add('IPython commit', "{} ({})".format(inf['commit_hash'], inf['commit_source']))
    _add('IPython package', compress_user(inf['ipython_path']))
    _add('Python version', inf['sys_version'].replace('\n',''))
    _add('sys.executable', compress_user(inf['sys_executable']))
    _add('Platform', inf['platform'])

    width = max(len(n) for (n,v) in out)
    out = ["{:<{width}}: {}\n".format(n, v, width=width) for (n,v) in out]

    avail = []
    not_avail = []

    for k, is_avail in have.items():
        if is_avail:
            avail.append(k)
        else:
            not_avail.append(k)

    if avail:
        out.append('\nTools and libraries available at test time:\n')
        avail.sort()
        out.append('   ' + ' '.join(avail)+'\n')

    if not_avail:
        out.append('\nTools and libraries NOT available at test time:\n')
        not_avail.sort()
        out.append('   ' + ' '.join(not_avail)+'\n')

    return ''.join(out)

def run_iptestall(options):
    """Run the entire IPython test suite by calling nose and trial.

    This function constructs :class:`IPTester` instances for all IPython
    modules and package and then runs each of them.  This causes the modules
    and packages of IPython to be tested each in their own subprocess using
    nose.

    Parameters
    ----------

    All parameters are passed as attributes of the options object.

    testgroups : list of str
      Run only these sections of the test suite. If empty, run all the available
      sections.

    fast : int or None
      Run the test suite in parallel, using n simultaneous processes. If None
      is passed, one process is used per CPU core. Default 1 (i.e. sequential)

    inc_slow : bool
      Include slow tests. By default, these tests aren't run.

    url : unicode
      Address:port to use when running the JS tests.

    xunit : bool
      Produce Xunit XML output. This is written to multiple foo.xunit.xml files.

    coverage : bool or str
      Measure code coverage from tests. True will store the raw coverage data,
      or pass 'html' or 'xml' to get reports.

    extra_args : list
      Extra arguments to pass to the test subprocesses, e.g. '-v'
    """
    to_run, not_run = prepare_controllers(options)

    def justify(ltext, rtext, width=70, fill='-'):
        ltext += ' '
        rtext = (' ' + rtext).rjust(width - len(ltext), fill)
        return ltext + rtext

    # Run all test runners, tracking execution time
    failed = []
    t_start = time.time()

    print()
    if options.fast == 1:
        # This actually means sequential, i.e. with 1 job
        for controller in to_run:
            print('Test group:', controller.section)
            sys.stdout.flush()  # Show in correct order when output is piped
            controller, res = do_run(controller, buffer_output=False)
            if res:
                failed.append(controller)
                if res == -signal.SIGINT:
                    print("Interrupted")
                    break
            print()

    else:
        # Run tests concurrently
        try:
            pool = multiprocessing.pool.ThreadPool(options.fast)
            for (controller, res) in pool.imap_unordered(do_run, to_run):
                res_string = 'OK' if res == 0 else 'FAILED'
                print(justify('Test group: ' + controller.section, res_string))
                if res:
                    print(decode(controller.stdout))
                    failed.append(controller)
                    if res == -signal.SIGINT:
                        print("Interrupted")
                        break
        except KeyboardInterrupt:
            return

    for controller in not_run:
        print(justify('Test group: ' + controller.section, 'NOT RUN'))

    t_end = time.time()
    t_tests = t_end - t_start
    nrunners = len(to_run)
    nfail = len(failed)
    # summarize results
    print('_'*70)
    print('Test suite completed for system with the following information:')
    print(report())
    took = "Took %.3fs." % t_tests
    print('Status: ', end='')
    if not failed:
        print('OK (%d test groups).' % nrunners, took)
    else:
        # If anything went wrong, point out what command to rerun manually to
        # see the actual errors and individual summary
        failed_sections = [c.section for c in failed]
        print('ERROR - {} out of {} test groups failed ({}).'.format(nfail,
                                  nrunners, ', '.join(failed_sections)), took)
        print()
        print('You may wish to rerun these, with:')
        print('  iptest', *failed_sections)
        print()

    if options.coverage:
        from coverage import coverage, CoverageException
        cov = coverage(data_file='.coverage')
        cov.combine()
        cov.save()

        # Coverage HTML report
        if options.coverage == 'html':
            html_dir = 'ipy_htmlcov'
            shutil.rmtree(html_dir, ignore_errors=True)
            print("Writing HTML coverage report to %s/ ... " % html_dir, end="")
            sys.stdout.flush()

            # Custom HTML reporter to clean up module names.
            from coverage.html import HtmlReporter
            class CustomHtmlReporter(HtmlReporter):
                def find_code_units(self, morfs):
                    super(CustomHtmlReporter, self).find_code_units(morfs)
                    for cu in self.code_units:
                        nameparts = cu.name.split(os.sep)
                        if 'IPython' not in nameparts:
                            continue
                        ix = nameparts.index('IPython')
                        cu.name = '.'.join(nameparts[ix:])

            # Reimplement the html_report method with our custom reporter
            cov.get_data()
            cov.config.from_args(omit='*{0}tests{0}*'.format(os.sep), html_dir=html_dir,
                                 html_title='IPython test coverage',
                                )
            reporter = CustomHtmlReporter(cov, cov.config)
            reporter.report(None)
            print('done.')

        # Coverage XML report
        elif options.coverage == 'xml':
            try:
                cov.xml_report(outfile='ipy_coverage.xml')
            except CoverageException as e:
                print('Generating coverage report failed. Are you running javascript tests only?')
                import traceback
                traceback.print_exc()

    if failed:
        # Ensure that our exit code indicates failure
        sys.exit(1)

argparser = argparse.ArgumentParser(description='Run IPython test suite')
argparser.add_argument('testgroups', nargs='*',
                    help='Run specified groups of tests. If omitted, run '
                    'all tests.')
argparser.add_argument('--all', action='store_true',
                    help='Include slow tests not run by default.')
argparser.add_argument('-j', '--fast', nargs='?', const=None, default=1, type=int,
                    help='Run test sections in parallel. This starts as many '
                    'processes as you have cores, or you can specify a number.')
argparser.add_argument('--xunit', action='store_true',
                    help='Produce Xunit XML results')
argparser.add_argument('--coverage', nargs='?', const=True, default=False,
                    help="Measure test coverage. Specify 'html' or "
                    "'xml' to get reports.")
argparser.add_argument('--subproc-streams', default='capture',
                    help="What to do with stdout/stderr from subprocesses. "
                    "'capture' (default), 'show' and 'discard' are the options.")

def default_options():
    """Get an argparse Namespace object with the default arguments, to pass to
    :func:`run_iptestall`.
    """
    options = argparser.parse_args([])
    options.extra_args = []
    return options

def main():
    # iptest doesn't work correctly if the working directory is the
    # root of the IPython source tree. Tell the user to avoid
    # frustration.
    if os.path.exists(os.path.join(os.getcwd(),
                                   'IPython', 'testing', '__main__.py')):
        print("Don't run iptest from the IPython source directory",
              file=sys.stderr)
        sys.exit(1)
    # Arguments after -- should be passed through to nose. Argparse treats
    # everything after -- as regular positional arguments, so we separate them
    # first.
    try:
        ix = sys.argv.index('--')
    except ValueError:
        to_parse = sys.argv[1:]
        extra_args = []
    else:
        to_parse = sys.argv[1:ix]
        extra_args = sys.argv[ix+1:]

    options = argparser.parse_args(to_parse)
    options.extra_args = extra_args

    run_iptestall(options)


if __name__ == '__main__':
    main()
