import StringIO
import difflib
import errno
import gettext
import imp
import os
import shutil
import stat
import subprocess
import sys
import tempfile
import unittest
import urllib

import __init__

from mercurial import commands
from mercurial import context
from mercurial import hg
from mercurial import i18n
from mercurial import node
from mercurial import ui
from mercurial import extensions

from hgsubversion import util

# Documentation for Subprocess.Popen() says:
#   "Note that on Windows, you cannot set close_fds to true and
#   also redirect the standard handles by setting stdin, stdout or
#   stderr."
canCloseFds='win32' not in sys.platform

if not 'win32' in sys.platform:
    def kill_process(popen_obj):
        os.kill(popen_obj.pid, 9)
else:
    import ctypes
    from ctypes.wintypes import BOOL, DWORD, HANDLE, UINT

    def win_status_check(result, func, args):
        if result == 0:
            raise ctypes.WinError()
        return args

    def WINAPI(returns, func, *params):
        assert len(params) % 2 == 0

        func.argtypes = tuple(params[0::2])
        func.resvalue = returns
        func.errcheck = win_status_check

        return func

    # dwDesiredAccess
    PROCESS_TERMINATE = 0x0001

    OpenProcess = WINAPI(HANDLE, ctypes.windll.kernel32.OpenProcess,
        DWORD, 'dwDesiredAccess',
        BOOL, 'bInheritHandle',
        DWORD, 'dwProcessId',
    )

    CloseHandle =  WINAPI(BOOL, ctypes.windll.kernel32.CloseHandle,
        HANDLE, 'hObject'
    )

    TerminateProcess = WINAPI(BOOL, ctypes.windll.kernel32.TerminateProcess,
        HANDLE, 'hProcess',
        UINT, 'uExitCode'
    )

    def kill_process(popen_obj):
        phnd = OpenProcess(PROCESS_TERMINATE, False, popen_obj.pid)
        TerminateProcess(phnd, 1)
        CloseHandle(phnd)

# Fixtures that need to be pulled at a subdirectory of the repo path
subdir = {'truncatedhistory.svndump': '/project2',
          'fetch_missing_files_subdir.svndump': '/foo',
          'empty_dir_in_trunk_not_repo_root.svndump': '/project',
          'project_root_not_repo_root.svndump': '/dummyproj',
          'project_name_with_space.svndump': '/project name',
          }

FIXTURES = os.path.join(os.path.abspath(os.path.dirname(__file__)),
                        'fixtures')

def filtermanifest(manifest):
    return filter(lambda x: x not in ('.hgtags', '.hgsvnexternals', ),
                  manifest)

def fileurl(path):
    path = os.path.abspath(path).replace(os.sep, '/')
    drive, path = os.path.splitdrive(path)
    if drive:
        drive = '/' + drive
    url = 'file://%s%s' % (drive, path)
    return url

def testui(stupid=False, layout='auto'):
    u = ui.ui()
    bools = {True: 'true', False: 'false'}
    u.setconfig('ui', 'quiet', bools[True])
    u.setconfig('hgsubversion', 'stupid', bools[stupid])
    u.setconfig('hgsubversion', 'layout', layout)
    return u

def load_svndump_fixture(path, fixture_name):
    '''Loads an svnadmin dump into a fresh repo at path, which should not
    already exist.
    '''
    if os.path.exists(path): rmtree(path)
    subprocess.call(['svnadmin', 'create', path,],
                    stdout=subprocess.PIPE, stderr=subprocess.STDOUT)
    inp = open(os.path.join(FIXTURES, fixture_name))
    proc = subprocess.Popen(['svnadmin', 'load', path,], stdin=inp,
                            stdout=subprocess.PIPE, stderr=subprocess.STDOUT)
    proc.communicate()

def load_fixture_and_fetch(fixture_name, repo_path, wc_path, stupid=False, subdir='',
                           noupdate=True, layout='auto'):
    load_svndump_fixture(repo_path, fixture_name)
    if subdir:
        repo_path += '/' + subdir
    _ui = testui(stupid=stupid, layout=layout)
    commands.clone(_ui, fileurl(repo_path), wc_path, noupdate=noupdate)
    return hg.repository(testui(), wc_path)

def rmtree(path):
    # Read-only files cannot be removed under Windows
    for root, dirs, files in os.walk(path):
        for f in files:
            f = os.path.join(root, f)
            try:
                s = os.stat(f)
            except OSError, e:
                if e.errno == errno.ENOENT:
                    continue
                raise
            if (s.st_mode & stat.S_IWRITE) == 0:
                os.chmod(f, s.st_mode | stat.S_IWRITE)
    shutil.rmtree(path)


class TestBase(unittest.TestCase):
    def setUp(self):
        self.oldenv = dict([(k, os.environ.get(k, None), ) for k in
                           ('LANG', 'LC_ALL', 'HGRCPATH', )])
        self.oldt = i18n.t
        os.environ['LANG'] = os.environ['LC_ALL'] = 'C'
        i18n.t = gettext.translation('hg', i18n.localedir, fallback=True)

        self.oldwd = os.getcwd()
        self.tmpdir = tempfile.mkdtemp(
            'svnwrap_test', dir=os.environ.get('HGSUBVERSION_TEST_TEMP', None))
        self.hgrc = os.path.join(self.tmpdir, '.hgrc')
        os.environ['HGRCPATH'] = self.hgrc
        rc = open(self.hgrc, 'w')
        for l in '[extensions]', 'hgsubversion=':
            print >> rc, l

        self.repo_path = '%s/testrepo' % self.tmpdir
        self.wc_path = '%s/testrepo_wc' % self.tmpdir

        # Previously, we had a MockUI class that wrapped ui, and giving access
        # to the stream. The ui.pushbuffer() and ui.popbuffer() can be used
        # instead. Using the regular UI class, with all stderr redirected to
        # stdout ensures that the test setup is much more similar to usage
        # setups.
        self.patch = (ui.ui.write_err, ui.ui.write)
        setattr(ui.ui, self.patch[0].func_name, self.patch[1])

    def tearDown(self):
        for var, val in self.oldenv.iteritems():
            if val is None:
                del os.environ[var]
            else:
                os.environ[var] = val
        i18n.t = self.oldt
        rmtree(self.tmpdir)
        os.chdir(self.oldwd)
        setattr(ui.ui, self.patch[0].func_name, self.patch[0])

    def assertStringEqual(self, l, r):
        try:
            self.assertEqual(l, r, 'failed string equality check, see stdout for details')
        except:
            add_nl = lambda li: map(lambda x: x+'\n', li)
            print 'failed expectation:'
            print ''.join(difflib.unified_diff(
                add_nl(l.splitlines()), add_nl(r.splitlines()),
                fromfile='expected', tofile='got'))
            raise

    def ui(self, stupid=False, layout='auto'):
        return testui(stupid, layout)

    def _load_fixture_and_fetch(self, fixture_name, subdir=None, stupid=False, layout='auto'):
        if layout == 'single':
            if subdir is None:
                subdir = 'trunk'
        elif subdir is None:
            subdir = ''
        return load_fixture_and_fetch(fixture_name, self.repo_path,
                                      self.wc_path, subdir=subdir,
                                      stupid=stupid, layout=layout)

    # define this as a property so that it reloads anytime we need it
    @property
    def repo(self):
        return hg.repository(testui(), self.wc_path)

    def pushrevisions(self, stupid=False, expected_extra_back=0):
        before = len(self.repo)
        self.repo.ui.setconfig('hgsubversion', 'stupid', str(stupid))
        commands.push(self.repo.ui, self.repo)
        after = len(self.repo)
        self.assertEqual(expected_extra_back, after - before)

    def svnls(self, path, rev='HEAD'):
        path = self.repo_path + '/' + path
        path = util.normalize_url(fileurl(path))
        args = ['svn', 'ls', '-r', rev, '-R', path]
        p = subprocess.Popen(args,
                             stdout=subprocess.PIPE,
                             stderr=subprocess.STDOUT)
        stdout, stderr = p.communicate()
        if p.returncode:
            raise Exception('svn ls failed on %s: %r' % (path, stderr))
        entries = [e.strip('/') for e in stdout.splitlines()]
        entries.sort()
        return entries

    def commitchanges(self, changes, parent='tip', message='automated test'):
        """Commit changes to mercurial directory

        'changes' is a sequence of tuples (source, dest, data). It can look
        like:
        - (source, source, data) to set source content to data
        - (source, dest, None) to set dest content to source one, and mark it as
        copied from source.
        - (source, dest, data) to set dest content to data, and mark it as copied
        from source.
        - (source, None, None) to remove source.
        """
        repo = self.repo
        parentctx = repo[parent]

        changed, removed = [], []
        for source, dest, newdata in changes:
            if dest is None:
                removed.append(source)
            else:
                changed.append(dest)

        def filectxfn(repo, memctx, path):
            if path in removed:
                raise IOError(errno.ENOENT,
                              "File \"%s\" no longer exists" % path)
            entry = [e for e in changes if path == e[1]][0]
            source, dest, newdata = entry
            if newdata is None:
                newdata = parentctx[source].data()
            copied = None
            if source != dest:
                copied = source
            return context.memfilectx(path=dest,
                                      data=newdata,
                                      islink=False,
                                      isexec=False,
                                      copied=copied)

        ctx = context.memctx(repo,
                             (parentctx.node(), node.nullid),
                             message,
                             changed + removed,
                             filectxfn,
                             'an_author',
                             '2008-10-07 20:59:48 -0500')
        nodeid = repo.commitctx(ctx)
        repo = self.repo
        hg.clean(repo, nodeid)
        return nodeid

    def assertchanges(self, changes, ctx):
        """Assert that all 'changes' (as in defined in commitchanged())
        went into ctx.
        """
        for source, dest, data in changes:
            if dest is None:
                self.assertTrue(source not in ctx)
                continue
            self.assertTrue(dest in ctx)
            if data is None:
                data = ctx.parents()[0][source].data()
            self.assertEqual(ctx[dest].data(), data)
            if dest != source:
                copy = ctx[dest].renamed()
                self.assertEqual(copy[0], source)

    def draw(self, repo):
        """Helper function displaying a repository graph, especially
        useful when debugging comprehensive tests.
        """
        # Could be more elegant, but it works with stock hg
        _ui = ui.ui()
        _ui.setconfig('extensions', 'graphlog', '')
        extensions.loadall(_ui)
        graphlog = extensions.find('graphlog')
        templ = """\
changeset: {rev}:{node|short}
branch:    {branches}
tags:      {tags}
summary:   {desc|firstline}
files:     {files}

"""
        graphlog.graphlog(_ui, repo, rev=None, template=templ)