#!/usr/bin/env python 
#
# bug-bugzilla: a command-line script to post bugs to a Bugzilla instance
#
# Authors: Christian Reis <kiko@async.com.br>
#          Eric S. Raymond <esr@thyrsus.com>
#
# This is version 0.5.
# 
# For a usage hint run bug-bugzilla --help
#
# TODO: use RDF output to pick up valid options, as in
#   http://www.async.com.br/~kiko/mybugzilla/config.cgi?ctype=rdf

import sys

def error(m):
    sys.stderr.write("bug-bugzilla: %s\n" % m)
    sys.stderr.flush()
    sys.exit(1)

if sys.version[:6] < '2.3.0':
    error("you must upgrade to Python 2.3 or higher to use this script.")

import urllib, re, os, netrc, email.Parser, optparse

# Set up some aliases -- partly to hide the less friendly fieldnames
# behind the names actually used for them in the stock web page presentation,
# and partly to provide a place for mappings if the Bugzilla fieldnames
# ever change.
field_aliases = (('hardware', 'rep_platform'),
                 ('os', 'op_sys'),
                 ('summary', 'short_desc'),
                 ('description', 'comment'),
                 ('depends-on', 'dependson'),
                 ('status', 'bug_status'),
                 ('severity', 'bug_severity'),
                 ('URL', 'bug_file_loc'),)

def header_to_field(hdr):
    hdr = hdr.lower().replace("-", "_")
    for (alias, name) in field_aliases:
        if hdr == alias:
            hdr = name
            break
    return hdr

def field_to_header(hdr):
    hdr = "-".join(map(lambda x: x.capitalize(), hdr.split("_")))
    for (alias, name) in field_aliases:
        if hdr == name:
            hdr = alias
            break
    return hdr

def setup_parser():
    # Take override values from the command line
    parser = optparse.OptionParser(usage="usage: %prog [options] bugzilla-url")
    parser.add_option('-b', '--status', dest='bug_status',
                      help='Set the Status field.')
    parser.add_option('-u', '--url', dest='bug_file_loc',
                      help='Set the URL field.')
    parser.add_option('-p', '--product', dest='product',
                      help='Set the Product field.')
    parser.add_option('-v', '--version', dest='version',
                      help='Set the Version field.')
    parser.add_option('-c', '--component', dest='component',
                      help='Set the Component field.')
    parser.add_option('-s', '--summary', dest='short_desc',
                      help='Set the Summary field.')
    parser.add_option('-H', '--hardware', dest='rep_platform',
                      help='Set the Hardware field.')
    parser.add_option('-o', '--os', dest='op_sys',
                      help='Set the Operating-system field.')
    parser.add_option('-r', '--priority', dest='priority',
                      help='Set the Priority field.')
    parser.add_option('-x', '--severity', dest='bug_severity',
                      help='Set the Severity field.')
    parser.add_option('-d', '--description', dest='comment',
                      help='Set the Description field.')
    parser.add_option('-a', '--assigned-to', dest='assigned_to',
                      help='Set the Assigned-To field.')
    parser.add_option('-C', '--cc', dest='cc',
                      help='Set the Cc field.')
    parser.add_option('-k', '--keywords', dest='keywords',
                      help='Set the Keywords field.')
    parser.add_option('-D', '--depends-on', dest='dependson',
                      help='Set the Depends-On field.')
    parser.add_option('-B', '--blocked', dest='blocked',
                      help='Set the Blocked field.')
    parser.add_option('-n', '--no-stdin', dest='read',
                      default=True, action='store_false',
                      help='Suppress reading fields from stdin.')
    return parser

# Fetch user's credential for access to this Bugzilla instance.
def get_credentials(bugzilla):
    # Work around a quirk in the Python implementation.
    # The URL has to be quoted, otherwise the parser barfs on the colon.
    # But the parser doesn't strip the quotes.
    authenticate_on = '"' + bugzilla + '"'
    try:
        credentials = netrc.netrc()
    except netrc.NetrcParseError, e:
        error("ill-formed .netrc: %s:%s %s" % (e.filename, e.lineno, e.msg))
    except IOError, e:
        error("missing .netrc file %s" % str(e).split()[-1])
    ret = credentials.authenticators(authenticate_on)
    if not ret:
        # Apparently, an invalid machine URL will cause credentials == None
        error("no credentials for Bugzilla instance at %s" % bugzilla)
    return ret

def process_options(options):
    data = {}
    # Initialize bug report fields from message on standard input
    if options.read:
        message_parser = email.Parser.Parser()
        message = message_parser.parse(sys.stdin)
        for (key, value) in message.items():
            data.update({header_to_field(key) : value})
        if not 'comment' in data:
            data['comment'] = message.get_payload() 

    # Merge in options from the command line; they override what's on stdin.
    for (key, value) in options.__dict__.items():
        if key != 'read' and value != None:
            data[key] = value
    return data

def ensure_defaults(data):
    # Provide some defaults if the user did not supply them.
    if 'op_sys' not in data:
        if sys.platform.startswith('linux'):
            data['op_sys'] = 'Linux'
    if 'rep_platform' not in data:
        data['rep_platform'] = 'PC'
    if 'bug_status' not in data:
        data['bug_status'] = 'NEW'
    if 'bug_severity' not in data:
        data['bug_severity'] = 'normal'
    if 'bug_file_loc' not in data:
        data['bug_file_loc'] = 'http://'        # Yes, Bugzilla needs this
    if 'priority' not in data:
        data['priority'] = 'P2'

def validate_fields(data):
    # Fields for validation
    required_fields = (
        "bug_status", "bug_file_loc", "product", "version", "component",
        "short_desc", "rep_platform", "op_sys", "priority", "bug_severity",
        "comment",
    )
    legal_fields = required_fields + (
        "assigned_to", "cc", "keywords", "dependson", "blocked",
    )
    my_fields = data.keys()
    for field in my_fields:
        if field not in legal_fields:
            error("invalid field: %s" % field_to_header(field))
    for field in required_fields:
        if field not in my_fields:
            error("required field missing: %s" % field_to_header(field))
    
    if not data['short_desc']:
        error("summary for bug submission must not be empty")
    
    if not data['comment']:
        error("comment for bug submission must not be empty")

#
# POST-specific functions
#

def submit_bug_POST(bugzilla, data):
    # Move the request over the wire
    postdata = urllib.urlencode(data)
    url = urllib.urlopen("%s/post_bug.cgi" % bugzilla, postdata)
    ret = url.read()
    check_result_POST(ret, data)

def check_result_POST(ret, data):
    # XXX We can move pre-validation out of here as soon as we pick up
    # the valid options from config.cgi -- it will become a simple
    # assertion and ID-grabbing step.
    #
    # XXX: We use get() here which may return None, but since the user
    # might not have provided these options, we don't want to die on
    # them.
    version = data.get('version')
    product = data.get('product')
    component = data.get('component')
    priority = data.get('priority')
    severity = data.get('bug_severity')
    status = data.get('bug_status')
    assignee = data.get('assigned_to')
    platform = data.get('rep_platform')
    opsys = data.get('op_sys')
    keywords = data.get('keywords')
    deps = data.get('dependson', '') + " " + data.get('blocked', '') 
    deps = deps.replace(" ", ", ")
    # XXX: we should really not be using plain find() here, as it can
    # match the bug content inadvertedly
    if ret.find("A legal Version was not") != -1:
        error("version %r does not exist for component %s:%s" % 
                (version, product, component))
    if ret.find("A legal Priority was not") != -1:
        error("priority %r does not exist in "
              "this Bugzilla instance" % priority)
    if ret.find("A legal Severity was not") != -1:
        error("severity %r does not exist in "
              "this Bugzilla instance" % severity)
    if ret.find("A legal Status was not") != -1:
        error("status %r is not a valid creation status in "
              "this Bugzilla instance" % status)
    if ret.find("A legal Platform was not") != -1:
        error("platform %r is not a valid platform in "
              "this Bugzilla instance" % platform)
    if ret.find("A legal OS/Version was not") != -1:
        error("%r is not a valid OS in "
              "this Bugzilla instance" % opsys)
    if ret.find("Invalid Username") != -1:
        error("invalid credentials submitted")
    if ret.find("Component Needed") != -1:
        error("the component %r does not exist in "
              "this Bugzilla instance" % component)
    if ret.find("Unknown Keyword") != -1:
        error("keyword(s) %r not registered in "
              "this Bugzilla instance" % keywords)
    if ret.find("The product name") != -1:
        error("Product %r does not exist in this "
              "Bugzilla instance" % product)
    # XXX: this should be smarter
    if ret.find("does not exist") != -1:
        error("Could not mark dependencies for bugs %s: one or "
              "more bugs didn't exist in this Bugzilla instance" % deps)
    if ret.find("Match Failed") != -1:
        # XXX: invalid CC hits on this error too
        error("the bug assignee %r isn't registered in " 
              "this Bugzilla instance" % assignee)
    # If all is well, return bug number posted
    m = re.search("Bug ([0-9]+) Submitted", ret)
    if not m:
        print ret
        error("Internal error: bug id not found; please report a bug")
    id = m.group(1)
    print "Bug %s posted." % id

#
#
#

if __name__ == "__main__":
    parser = setup_parser()

    # Parser will print help and exit here if we specified --help
    (options, args) = parser.parse_args()

    if len(args) != 1:
        parser.error("missing Bugzilla host URL")

    bugzilla = args[0]
    data = process_options(options)

    login, account, password = get_credentials(bugzilla)
    if "@" not in login:   # no use even trying to submit
        error("login %r is invalid (it should be an email address)" % login)

    ensure_defaults(data)
    validate_fields(data)

    # Attach authentication information
    data.update({'Bugzilla_login'    : login,
                 'Bugzilla_password' : password,
                 'GoAheadAndLogIn'   : 1,
                 'form_name'         : 'enter_bug'})

    submit_bug_POST(bugzilla, data)