import test_util

import os
import pickle
import unittest

from mercurial import context
from mercurial import extensions
from mercurial import hg
from mercurial import ui

from hgsubversion import svncommands
from hgsubversion import svnmeta

# These test repositories have harmless skew in rebuildmeta for the
# last-pulled-rev because the last rev in svn causes absolutely no
# changes in hg.
expect_youngest_skew = [('file_mixed_with_branches.svndump', False, False),
                        ('file_mixed_with_branches.svndump', True, False),
                        ('unrelatedbranch.svndump', False, False),
                        ('unrelatedbranch.svndump', True, False),
                        ]



def _do_case(self, name, stupid, single):
    subdir = test_util.subdir.get(name, '')
    layout = 'auto'
    if single:
        layout = 'single'
    repo, repo_path = self.load_and_fetch(name, subdir=subdir, stupid=stupid,
                                          layout=layout)
    assert len(self.repo) > 0
    wc2_path = self.wc_path + '_clone'
    u = ui.ui()
    src, dest = test_util.hgclone(u, self.wc_path, wc2_path, update=False)
    src = getattr(src, 'local', lambda: src)()
    dest = getattr(dest, 'local', lambda: dest)()

    # insert a wrapper that prevents calling changectx.children()
    def failfn(orig, ctx):
        self.fail('calling %s is forbidden; it can cause massive slowdowns '
                  'when rebuilding large repositories' % orig)

    origchildren = getattr(context.changectx, 'children')
    extensions.wrapfunction(context.changectx, 'children', failfn)

    try:
        svncommands.rebuildmeta(u, dest,
                                args=[test_util.fileurl(repo_path +
                                                        subdir), ])
    finally:
        # remove the wrapper
        context.changectx.children = origchildren

    self._run_assertions(name, stupid, single, src, dest, u)

    wc3_path = self.wc_path + '_partial'
    src, dest = test_util.hgclone(u,
                                  self.wc_path,
                                  wc3_path,
                                  update=False,
                                  rev=[0])
    srcrepo = getattr(src, 'local', lambda: src)()
    dest = getattr(dest, 'local', lambda: dest)()

    # insert a wrapper that prevents calling changectx.children()
    extensions.wrapfunction(context.changectx, 'children', failfn)

    try:
        svncommands.rebuildmeta(u, dest,
                                args=[test_util.fileurl(repo_path +
                                                        subdir), ])
    finally:
        # remove the wrapper
        context.changectx.children = origchildren

    dest.pull(src)

    # insert a wrapper that prevents calling changectx.children()
    extensions.wrapfunction(context.changectx, 'children', failfn)
    try:
        svncommands.updatemeta(u, dest,
                               args=[test_util.fileurl(repo_path +
                                                        subdir), ])
    finally:
        # remove the wrapper
        context.changectx.children = origchildren

    self._run_assertions(name, stupid, single, srcrepo, dest, u)


def _run_assertions(self, name, stupid, single, src, dest, u):

    self.assertTrue(os.path.isdir(os.path.join(src.path, 'svn')),
                    'no .hg/svn directory in the source!')
    self.assertTrue(os.path.isdir(os.path.join(src.path, 'svn')),
                    'no .hg/svn directory in the destination!')
    dest = hg.repository(u, os.path.dirname(dest.path))
    for tf in ('lastpulled', 'rev_map', 'uuid', 'tagmap', 'layout', 'subdir',):

        stf = os.path.join(src.path, 'svn', tf)
        self.assertTrue(os.path.isfile(stf), '%r is missing!' % stf)
        dtf = os.path.join(dest.path, 'svn', tf)
        self.assertTrue(os.path.isfile(dtf), '%r is missing!' % tf)
        old, new = open(stf).read(), open(dtf).read()
        if tf == 'lastpulled' and (name,
                                   stupid, single) in expect_youngest_skew:
            self.assertNotEqual(old, new,
                                'rebuildmeta unexpected match on youngest rev!')
            continue
        self.assertMultiLineEqual(old, new, tf + ' differs')
        self.assertEqual(src.branchtags(), dest.branchtags())
    srcbi = pickle.load(open(os.path.join(src.path, 'svn', 'branch_info')))
    destbi = pickle.load(open(os.path.join(dest.path, 'svn', 'branch_info')))
    self.assertEqual(sorted(srcbi.keys()), sorted(destbi.keys()))
    revkeys = svnmeta.SVNMeta(dest).revmap.keys()
    for branch in destbi:
        srcinfo = srcbi[branch]
        destinfo = destbi[branch]
        if srcinfo[:2] == (None, 0) or destinfo[:2] == (None, 0):
            self.assertTrue(srcinfo[2] <= destinfo[2],
                            'Latest revision for %s decreased from %d to %d!'
                            % (branch or 'default', srcinfo[2], destinfo[2]))
            self.assertEqual(srcinfo[0], destinfo[0])
        else:
            pr = sorted(filter(lambda x: x[1] == srcinfo[0] and x[0] <= srcinfo[1],
                        revkeys), reverse=True)[0][0]
            self.assertEqual(pr, destinfo[1])
            self.assertEqual(srcinfo[2], destinfo[2])


def buildmethod(case, name, stupid, single):
    m = lambda self: self._do_case(case, stupid, single)
    m.__name__ = name
    m.__doc__ = ('Test rebuildmeta on %s with %s replay. (%s)' %
                 (case,
                  (stupid and 'stupid') or 'real',
                  (single and 'single') or 'standard',
                  )
                 )
    return m


skip = set([
    'project_root_not_repo_root.svndump',
    'corrupt.svndump',
])

attrs = {'_do_case': _do_case,
         '_run_assertions': _run_assertions,
         }
for case in [f for f in os.listdir(test_util.FIXTURES) if f.endswith('.svndump')]:
    # this fixture results in an empty repository, don't use it
    if case in skip:
        continue
    bname = 'test_' + case[:-len('.svndump')]
    attrs[bname] = buildmethod(case, bname, False, False)
    name = bname + '_stupid'
    attrs[name] = buildmethod(case, name, True, False)
    name = bname + '_single'
    attrs[name] = buildmethod(case, name, False, True)

RebuildMetaTests = type('RebuildMetaTests', (test_util.TestBase,), attrs)


def suite():
    all_tests = [unittest.TestLoader().loadTestsFromTestCase(RebuildMetaTests),
          ]
    return unittest.TestSuite(all_tests)