#!/usr/bin/env python
# -*- coding: utf-8 -*-
#
# Copyright (C) 2013 Gauvain Pocentek <gauvain@pocentek.net>
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU Lesser General Public License as published by
# the Free Software Foundation, either version 3 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 Lesser General Public License for more details.
#
# You should have received a copy of the GNU Lesser General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.

import os
import sys
import re

try:
    from ConfigParser import ConfigParser
except:
    from configparser import ConfigParser

from inspect import getmro, getmembers, isclass

import gitlab

camel_re = re.compile('(.)([A-Z])')

def die(msg):
    sys.stderr.write(msg + "\n")
    sys.exit(1)

def whatToCls(what):
    return "".join([s.capitalize() for s in what.split("-")])

def clsToWhat(cls):
   return camel_re.sub(r'\1-\2', cls.__name__).lower()

def actionHelpList(cls):
    l = []
    for action in 'list', 'get', 'create', 'update', 'delete':
        attr = 'can' + action.capitalize()
        try:
            y = cls.__dict__[attr]
        except:
            y = gitlab.GitlabObject.__dict__[attr]
        if not y:
            continue

        detail = ''
        if action == 'list':
            detail = " ".join(["--%s=ARG" % x.replace('_', '-') for x in cls.requiredListAttrs])
            if detail:
                detail += " "
            detail += "--page=ARG --per-page=ARG"
        elif action in ['get', 'delete']:
            if cls not in [gitlab.CurrentUser]:
                detail = "--id=ARG "
                detail += " ".join(["--%s=ARG" % x.replace('_', '-') for x in cls.requiredGetAttrs])
        elif action == 'create':
            detail = " ".join(["--%s=ARG" % x.replace('_', '-') for x in cls.requiredCreateAttrs])
            if detail:
                detail += " "
            detail += " ".join(["[--%s=ARG]" % x.replace('_', '-') for x in cls.optionalCreateAttrs])
        elif action == 'update':
            detail = " ".join(["[--%s=ARG]" % x.replace('_', '-') for x in cls.requiredCreateAttrs])
            if detail:
                detail += " "
            detail += " ".join(["[--%s=ARG]" % x.replace('_', '-') for x in cls.optionalCreateAttrs])
        l.append("%s %s" % (action, detail))

    return (l)

def usage():
    print("usage: gitlab [--help] [--gitlab=GITLAB] [--fancy] what action [options]")
    print("")
    print("--gitlab=GITLAB: Specifies which python-gitlab.cfg configuration section should be used.")
    print("                 If not defined, the default selection will be used.")
    print("--fancy        : More verbose output.")
    print("--help         : Displays this message.")
    print("")
    print("Available `options` depend on which what/action couple is used.")
    print("If `action` is \"help\", available actions and options will be listed for `what`.")
    print("")
    print("Available `what` values are:")

    classes = []
    for name, o in getmembers(gitlab):
        if not isclass(o):
            continue
        if gitlab.GitlabObject in getmro(o) and o != gitlab.GitlabObject:
            classes.append(o)

    def s(a, b):
        if a.__name__ < b.__name__:
            return -1
        elif a.__name__ > b.__name__:
            return 1

    classes.sort(cmp=s)
    for cls in classes:
        print(" %s" % clsToWhat(cls))


gitlab_id = None
verbose = False

args = []
d = {}
for arg in sys.argv[1:]:
    if arg.startswith('--'):
        arg = arg[2:]

        if arg == 'help':
            usage()
            sys.exit(0)
        elif arg == 'fancy':
            verbose = True
            continue

        k, v = arg.split('=', 1)
        k = k.strip().replace('_', '-')
        v = v.strip()

        if k == 'gitlab':
            gitlab_id = v
        else:
            d[k] = v
    else:
        args.append(arg)

# read the config
config = ConfigParser()
config.read(['/etc/python-gitlab.cfg',
             os.path.expanduser('~/.python-gitlab.cfg')])

if gitlab_id is None:
    try:
        gitlab_id = config.get('global', 'default')
    except:
        die("Impossible to get the gitlab id (not specified in config file)")

try:
    gitlab_url = config.get(gitlab_id, 'url')
    gitlab_token = config.get(gitlab_id, 'private_token')
except:
    die("Impossible to get gitlab informations from configuration (%s)" % gitlab_id)

try:
    what = args.pop(0)
    action = args.pop(0)
except:
    die("Missing arguments")

if action not in ['get', 'list', 'update', 'create', 'delete', 'help']:
    die("Unknown action: %s. Use \"gitlab %s help\" to get details." % (action, what))

try:
    cls = gitlab.__dict__[whatToCls(what)]
except:
    die("Unknown object: %s" % what)

if gitlab.GitlabObject not in getmro(cls):
    die("Unknown object: %s" % what)

if action == "help":
    print("%s options:" % what)
    for item in actionHelpList(cls):
        print(" %s %s" % (what, item))

    sys.exit(0)

try:
    gl = gitlab.Gitlab(gitlab_url, private_token=gitlab_token)
    gl.auth()
except:
    die("Could not connect to GitLab (%s)" % gitlab_url)

if action == "create":
    if not cls.canCreate:
        die("%s objects can't be created" % what)

    try:
        o = cls(gl, d)
        o.save()
    except Exception as e:
        die("Impossible to create object (%s)" % str(e))

    if verbose:
        o.pretty_print()
    else:
        o.short_print()

    sys.exit(0)

elif action == "list":
    if not cls.canList:
        die("%s objects can't be listed" % what)

    try:
        l = cls.list(gl, **d)
    except Exception as e:
        die("Impossible to list objects (%s)" % str(e))

    for o in l:
        if verbose:
            o.pretty_print()
        else:
            o.short_print()
        print("")

    sys.exit(0)

elif action == "get":
    if not cls.canGet:
        die("%s objects can't be retrieved" % what)

    id = None
    if cls not in [gitlab.CurrentUser]:
        try:
            id = d.pop('id')
        except:
            die("Missing --id argument")

    try:
        o = cls(gl, id, **d)
    except Exception as e:
        die("Impossible to get object (%s)" % str(e))

    if verbose:
        o.pretty_print()
    else:
        o.short_print()

    sys.exit(0)

elif action == "delete":
    if not cls.canDelete:
        die("%s objects can't be deleted" % what)

    try:
        id = d.pop('id')
    except:
        die("Missing --id argument")

    try:
        o = cls(gl, id, **d)
    except Exception as e:
        die("Impossible to get object (%s)" % id, str(e))

    try:
        o.delete()
    except Exception as e:
        die("Impossible to destroy object (%s)" % str(e))

    sys.exit(0)

elif action == "update":
    if not cls.canDelete:
        die("%s objects can't be updated" % what)

    try:
        id = d.pop('id')
    except:
        die("Missing --id argument")

    try:
        o = cls(gl, id, **d)
    except Exception as e:
        die("Impossible to get object (%s)" % str(e))

    try:
        for k, v in d.items():
            o.__dict__[k] = v
        o.save()
    except Exception as e:
        die("Impossible to update object (%s)" % str(e))

    sys.exit(0)