#!/usr/bin/python

import os
import sys
import re
import getopt
import json
import subprocess

scriptname = os.path.basename(sys.argv[0])

cfg = dict()
cfg['abandon'] = False
cfg['code-review'] = ''
cfg['nodo'] = False
cfg['submit'] = False
cfg['verify'] = ''
cfg['verbose'] = 0

def verbose(s):
    if cfg['verbose'] > 0:
        sys.stderr.write(s)

class Enum(set):
    def __getattr__(self, name):
        if name in self:
            return name
        raise AttributeError

ArgType = Enum(['ID', 'COMMIT', 'CHANGE', 'QUERY'])

def get_arg_type(arg):
    if re.match('^I[0-9A-Fa-f]{40}$', arg):
        return ArgType.ID
    if re.match('^[0-9A-Fa-f]{40}$', arg):
        return ArgType.COMMIT
    if re.match('^[0-9]{1,8},[0-9]{1,4}$', arg) or re.match('^[0-9]{1,8}$', arg):
        return ArgType.CHANGE
    return ArgType.QUERY

def gerrit_list(host, query):
    argv = ['ssh', host, 'gerrit', 'query', '--format=JSON', query]
    verbose("exec: %s\n" % (' '.join(argv)))
    child = subprocess.Popen(argv, stdin=None, stdout=subprocess.PIPE, stderr=None)
    out, err = child.communicate()
    if child.returncode != 0:
        raise RuntimeError('Failed to execute %s\n' % (' '.join(argv)))
    res = []
    for line in out.split('\n'):
        if not line:
            continue
        try:
            j = json.loads(line)
            if 'id' in j:
                res.append(j)
        except:
            print "Failed to parse line: %s" % (line)
    return res

def gerrit_change_props(host, queryarg, id):
    argv = []
    argv.append('ssh')
    argv.append(host)
    argv.append('gerrit')
    argv.append('query')
    argv.append('--format=JSON')
    argv.append(queryarg)
    argv.append("%s" %(id))
    verbose("exec: %s\n" % (' '.join(argv)))
    child = subprocess.Popen(argv, stdin=None, stdout=subprocess.PIPE, stderr=None)
    out, err = child.communicate()
    if child.returncode != 0:
        sys.stderr.write('Failed to read manifest\n')
        sys.exit(1)
    lines = out.split('\n')
    props = json.loads(lines[0])
    return props

def gerrit_review(host, ids, args):
    argv = ['ssh', host, 'gerrit', 'review']
    argv.extend(ids)
    argv.extend(args)
    verbose("exec: %s\n" % (' '.join(argv)))
    if not cfg['nodo']:
        child = subprocess.Popen(argv, stdin=None, stdout=None, stderr=None)
        out, err = child.communicate()
        if child.returncode != 0:
            print "Error: Failed to review change %s" % (id)
            print "Command: %s" % (' '.join(argv))
            raise RuntimeError('Review failed')

def usage():
    print "Usage:"
    print "  %s [args] <host> <change-id> ..." % (scriptname)
    print "  %s [args] <host> <change-num[,patchset]> ..." % (scriptname)
    print "  %s [args] <host> <commit-hash> ..." % (scriptname)
    print "  %s [args] <host> <query>" % (scriptname)
    print "    --abandon           Abandon change"
    print "    --code-review <n>   Set code-review"
    print "    --cr <n>            Alias for --code-review"
    print "    --merge             Alias for --code-review=+2 --verify=+1 --submit"
    print "    --nodo              Do not make any changes on the server"
    print "    --submit            Submit change"
    print "    --verbose           Increase verbose level"
    print "    --verify <n>        Set verify"
    print ""
    print "Examples:"
    print "  %s --cr=+1 gerrit.example.com 12345" % (scriptname)
    print "  %s --merge gerrit.example.com status:open owner:superdev@example.com label:code-review=+1" % (scriptname)
    sys.exit(1)

optargs, argv = getopt.getopt(sys.argv[1:], 'ac:mnsv',
        ['abandon', 'code-review=', 'cr=', 'merge', 'nodo', 'submit', 'verbose', 'verify='])
for k, v in optargs:
    if k in ('-a', '--abandon'):
        cfg['abandon'] = True
    if k in ('-c', '--cr', '--code-review'):
        cfg['code-review'] = v
    if k in ('-m', '--merge'):
        cfg['code-review'] = '+2'
        cfg['verify'] = '+1'
        cfg['submit'] = True
    if k in ('-n', '--nodo'):
        cfg['nodo'] = True
    if k in ('-s', '--submit'):
        cfg['submit'] = True
    if k in ('-v', '--verbose'):
        cfg['verbose'] += 1
    if k in ('--verify'):
        cfg['verify'] = v

if len(argv) < 2:
    usage()

host = argv.pop(0)

if cfg['abandon']:
    if cfg['code-review'] or cfg['verify'] or cfg['submit']:
        print "Error: Cannot combine abandon with other actions"
        print ""
        usage()
else:
    if not (cfg['code-review'] or cfg['verify'] or cfg['submit']):
        print "Error: No actions specified"
        print ""
        usage()

argtype = get_arg_type(argv[0])
for arg in argv:
    t = get_arg_type(arg)
    if t != argtype:
        usage()

changes = []
if argtype == ArgType.ID:
    # Change-Id: use the current patch set
    for arg in argv:
        props = gerrit_change_props(host, '--current-patch-set', arg)
        change = "%s,%s" % (props['number'], props['currentPatchSet']['number'])
        changes.append(change)
elif argtype == ArgType.COMMIT:
    # Commit hash: find the patch set
    for arg in argv:
        props = gerrit_change_props(host, '--patch-sets', arg)
        change_num = props['number']
        patch_num = ''
        for ps in props['patchSets']:
            if ps['revision'] == arg:
                patch_num = ps['number']
                break
        if not patch_num:
            print "Error: Cannot find patch number for commit %s" % (arg)
            sys.exit(1)
        change = "%s,%s" % (change_num, patch_num)
        changes.append(change)
elif argtype == ArgType.CHANGE:
    # Change-Number: use the current patch set if not provided
    for arg in argv:
        if ',' in arg:
            change = arg
        else:
            props = gerrit_change_props(host, '--current-patch-set', arg)
            change = "%s,%s" % (arg, props['currentPatchSet']['number'])
        changes.append(change)
elif argtype == ArgType.QUERY:
    # Query: use the current patch set for each result
    res = gerrit_list(host, ' '.join(argv))
    for item in res:
        props = gerrit_change_props(host, '--current-patch-set', item['id'])
        change = "%s,%s" % (props['number'], props['currentPatchSet']['number'])
        changes.append(change)
else:
    print "Internal Error: Unhandled argument type."
    sys.exit(1)

# Handle code-review and verified
if cfg['code-review'] or cfg['verify']:
    args = []
    if cfg['code-review']:
        args.extend(['--code-review', cfg['code-review']])
    if cfg['verify']:
        args.extend(['--verified', cfg['verify']])
    gerrit_review(host, changes, args)

# Handle submit and abandon
if cfg['submit'] or cfg['verify']:
    args = []
    if cfg['submit']:
        args.append('--submit')
    if cfg['abandon']:
        args.append('--abandon')
    gerrit_review(host, changes, args)