# Copyright (C) 2004, 2005 by Martin Pool
# Copyright (C) 2005 by Canonical Ltd

# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.

# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.

# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

# TODO: Check ancestries are correct for every revision: includes
# every committed so far, and in a reasonable order.

# TODO: Also check non-mainline revisions mentioned as parents.

# TODO: Check for extra files in the control directory.

# TODO: Check revision, inventory and entry objects have all 
# required fields.


import bzrlib.ui
from bzrlib.trace import note, warning
from bzrlib.osutils import rename, sha_string, fingerprint_file
from bzrlib.trace import mutter
from bzrlib.errors import BzrCheckError, NoSuchRevision
from bzrlib.inventory import ROOT_ID
from bzrlib.branch import gen_root_id


class Check(object):
    """Check a branch"""
    def __init__(self, branch):
        self.branch = branch
        branch.lock_read()
        try:
            branch.weave_store.enable_cache = True
            branch.control_weaves.enable_cache = True
            self.run()
        finally:
            branch.unlock()
            branch.weave_store.enable_cache = False
            branch.control_weaves.enable_cache = False


    def run(self):
        branch = self.branch


        self.checked_text_cnt = 0
        self.checked_rev_cnt = 0
        self.repeated_text_cnt = 0
        self.missing_inventory_sha_cnt = 0
        self.missing_revision_cnt = 0
        # maps (file-id, version) -> sha1
        self.checked_texts = {}

        history = branch.revision_history()
        revno = 0
        revcount = len(history)

        last_rev_id = None
        self.progress = bzrlib.ui.ui_factory.progress_bar()
        for rev_id in history:
            self.progress.update('checking revision', revno, revcount)
            revno += 1
            self.check_one_rev(rev_id, last_rev_id)
            last_rev_id = rev_id
        self.progress.clear()
        self.report_results()


    def report_results(self):
        note('checked branch %s format %d',
             self.branch.base, 
             self.branch._branch_format)

        note('%6d revisions', self.checked_rev_cnt)
        note('%6d unique file texts', self.checked_text_cnt)
        note('%6d repeated file texts', self.repeated_text_cnt)
        if self.missing_inventory_sha_cnt:
            note('%d revisions are missing inventory_sha1',
                 self.missing_inventory_sha_cnt)
        if self.missing_revision_cnt:
            note('%d revisions are mentioned but not present',
                 self.missing_revision_cnt)


    def check_one_rev(self, rev_id, last_rev_id):
        """Check one revision.

        rev_id - the one to check

        last_rev_id - the previous one on the mainline, if any.
        """

        # mutter('    revision {%s}' % rev_id)
        branch = self.branch
        rev = branch.get_revision(rev_id)
        if rev.revision_id != rev_id:
            raise BzrCheckError('wrong internal revision id in revision {%s}'
                                % rev_id)

        # check the previous history entry is a parent of this entry
        if rev.parent_ids:
            if last_rev_id is None:
                raise BzrCheckError("revision {%s} has %d parents, but is the "
                                    "start of the branch"
                                    % (rev_id, len(rev.parent_ids)))
            for parent_id in rev.parent_ids:
                if parent_id == last_rev_id:
                    break
            else:
                raise BzrCheckError("previous revision {%s} not listed among "
                                    "parents of {%s}"
                                    % (last_rev_id, rev_id))
        elif last_rev_id:
            raise BzrCheckError("revision {%s} has no parents listed "
                                "but preceded by {%s}"
                                % (rev_id, last_rev_id))

        if rev.inventory_sha1:
            inv_sha1 = branch.get_inventory_sha1(rev_id)
            if inv_sha1 != rev.inventory_sha1:
                raise BzrCheckError('Inventory sha1 hash doesn\'t match'
                    ' value in revision {%s}' % rev_id)
        else:
            missing_inventory_sha_cnt += 1
            mutter("no inventory_sha1 on revision {%s}" % rev_id)
        self._check_revision_tree(rev_id)
        self.checked_rev_cnt += 1

    def _check_revision_tree(self, rev_id):
        tree = self.branch.revision_tree(rev_id)
        inv = tree.inventory
        seen_ids = {}
        for file_id in inv:
            if file_id in seen_ids:
                raise BzrCheckError('duplicated file_id {%s} '
                                    'in inventory for revision {%s}'
                                    % (file_id, rev_id))
            seen_ids[file_id] = True
        for file_id in inv:
            ie = inv[file_id]
            ie.check(self, rev_id, inv, tree)
        seen_names = {}
        for path, ie in inv.iter_entries():
            if path in seen_names:
                raise BzrCheckError('duplicated path %s '
                                    'in inventory for revision {%s}'
                                    % (path, rev_id))
            seen_names[path] = True


def check(branch):
    """Run consistency checks on a branch."""
    Check(branch)