import socket
import time
from subprocess import check_call

from genshi.builder import tag

from trac.core import implements, Component
from trac.ticket.api import ITicketActionController
from trac.ticket.default_workflow import ConfigurableTicketWorkflow
from trac.web.chrome import add_warning

from BranchActor import BranchActor
from RebranchActor import RebranchActor
from MergeActor import MergeActor
from CheckMergeActor import CheckMergeActor
from action_logic import is_branchable, is_rebranchable, is_mergeable, is_checkmergeable

class MergebotActionController(Component):
    """Support branching and merging operations for tickets.
    """
    implements(ITicketActionController)

    # ITicketActionController
    def get_ticket_actions(self, req, ticket):
        controller = ConfigurableTicketWorkflow(self.env)
        mergebot_operations = self._get_available_operations(req, ticket)
        if mergebot_operations:
            actions_we_handle = controller.get_actions_by_operation_for_req(req,
                ticket, 'mergebot')
        else:
            actions_we_handle = []
        return actions_we_handle

    def get_all_status(self):
        return []

    def render_ticket_action_control(self, req, ticket, action):
        actions = ConfigurableTicketWorkflow(self.env).actions
        label = actions[action]['name']
        hint = ''

        control_id = action + '_mergebot_op'
        mergebot_operations = self._get_available_operations(req, ticket)

        # TODO: allow the configuration to specify a sub-set of permitted
        # mergebot actions
        #self.config.get('ticket-workflow', action + '.mergebot')

        self.env.log.debug('render_ticket_action_control ops: %s', mergebot_operations)
        selected_value = req.args.get(control_id) or mergebot_operations[0]
        control = tag.select([tag.option(option, selected=(option == selected_value or None)) for option in mergebot_operations], name=control_id, id=control_id)

        return (label, control, hint)


    def get_ticket_changes(self, req, ticket, action):
        control_id = action + '_mergebot_op'
        selected_value = req.args.get(control_id)
        add_warning(req, 'Mergebot operation %s will be triggered' % selected_value)
        return {}

    def daemon_address(self):
        host = self.env.config.get('mergebot', 'listen.ip')
        port = self.env.config.getint('mergebot', 'listen.port')
        return (host, port)

    def start_daemon(self):
        check_call(['mergebotdaemon', self.env.path])
        time.sleep(1) # bleh

    def _daemon_cmd(self, cmd):
        self.log.debug('Sending mergebotdaemon: %r' % cmd)
        try:
            info_socket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
            info_socket.connect(self.daemon_address())
        except socket.error, e:
            # if we're refused, try starting the daemon and re-try
            if e and e[0] == 111:
                self.log.debug('connection to mergebotdaemon refused, trying to start mergebotdaemon')
                self.start_daemon()
            self.log.debug('Resending mergebotdaemon: %r' % cmd)
            info_socket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
            info_socket.connect(self.daemon_address())
        info_socket.sendall(cmd)
        self.log.debug('Reading mergebotdaemon response')
        raw = info_socket.recv(4096)
        info_socket.close()
        self.log.debug('Reading mergebotdaemon response was %r' % raw)
        return raw

    def apply_action_side_effects(self, req, ticket, action):
        self.log.info('applying mergebot side effect for ticket %s on action %s' % (ticket.id, action))
        control_id = action + '_mergebot_op'
        selected_value = req.args.get(control_id)

        result = self._daemon_cmd('ADD %s %s %s %s %s\n\QUIT\n' % (ticket.id, selected_value, ticket['component'], ticket['version'], req.authname or 'anonymous'))
        if 'OK' not in result:
            add_warning(req, result) # adding warnings in this method doesn't seem to work

    def _get_available_operations(self, req, ticket):
        mergebot_ops = []
        if req.perm.has_permission("MERGEBOT_BRANCH"):
            if is_branchable(ticket):
                mergebot_ops.append('branch')
            if is_rebranchable(ticket):
                mergebot_ops.append('rebranch')
        if is_checkmergeable(ticket) and req.perm.has_permission('MERGEBOT_VIEW'):
            mergebot_ops.append('checkmerge')
        if ticket['version'].startswith("#"):
            may_merge = req.perm.has_permission("MERGEBOT_MERGE_TICKET")
        else:
            may_merge = req.perm.has_permission("MERGEBOT_MERGE_RELEASE")
        if may_merge and is_mergeable(ticket):
            mergebot_ops.append('merge')
        return mergebot_ops