#!/usr/bin/env python3
# -*- coding: utf-8 -*-"
# Copyright 2021 The Chromium OS Authors. All rights reserved.
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.

"""Calculate initial revert list, and mark patches in rebase database accordingly"""

from __future__ import print_function
import sqlite3
import re
import time
from common import rebasedb


def NOW():
    """Return current time"""
    return int(time.time())


def mark_disposition(db, sha, disposition, reason, revert_sha):
    """Mark sha for given disposition.

    If available, add revert_sha into dsha.
    """

    c = db.cursor()

    print('    Marking %s for %s (%s)' % (sha, disposition, reason))

    cmd = 'UPDATE commits SET disposition="%s", reason="%s", updated="%d"' % (
        disposition, reason, NOW())
    if revert_sha:
        cmd += ', dsha="%s"' % revert_sha
    cmd += ' where sha="%s"' % sha

    print('  SQL: %s' % cmd)

    c.execute(cmd)


# date:
#         git show --format="%ct" -s ${sha}
# subject:
#        git show --format="%s" -s ${sha}
# file list:
#        git show --name-only --format="" ${sha}

# Insert a row of data
# c.execute("INSERT INTO commits VALUES (1489758183,sha,subject)")
# c.execute("INSERT INTO files VALUES (sha,filename)")
# sha and filename must be in ' '

rp = re.compile(r'Revert "(.*)"')

def handle_reverts():
    """Calculate initial revert list"""

    conn = sqlite3.connect(rebasedb)

    c = conn.cursor()
    c2 = conn.cursor()

    c.execute('select committed, sha, disposition, subject from commits')

    for (committed, sha, disposition, desc) in c.fetchall():
        # If the patch has already been dropped, don't bother any further
        if disposition == 'drop':
            continue
        m = rp.search(desc)
        if m:
            ndesc = m.group(1)
            print("Found revert : '%s' (%s)" % (desc.replace("'", "''"), sha))
            ndesc = ndesc.replace("'", "''")
            c2.execute("select committed, sha from commits where subject is '%s'" %
                       ndesc)
            # Search for commit closest to the revert in the past
            # (There may be multiple if the revert was repeated)
            revert_committed = None
            revert_sha = None
            for (_committed, _sha,) in c2.fetchall():
                if _committed < committed:
                    if not revert_sha or revert_committed < _committed:
                        revert_committed = _committed
                        revert_sha = _sha

            # <sha> is the revert of <revert_sha>. Mark both as reverted.
            if revert_sha:
                mark_disposition(conn, revert_sha, 'drop', 'reverted', sha)
                mark_disposition(conn, sha, 'drop', 'reverted', revert_sha)
                # Now check if we can find a FIXUP: of <revert_sha>. It must
                # have been committed between <revert_sha> and <sha>.
                fdesc = 'FIXUP: %s' % ndesc
                c2.execute(
                    "select committed, sha from commits where subject is '%s'" %
                    fdesc)
                for (_committed, _sha,) in c2.fetchall():
                    if revert_committed <= _committed <= committed:
                        mark_disposition(conn, _sha, 'drop', 'fixup/reverted',
                                         revert_sha)
            else:
                mark_disposition(conn, sha, 'pick', 'revisit', None)
                print('    No matching commit found')

    conn.commit()
    conn.close()


if __name__ == '__main__':
    handle_reverts()