from twisted.internet import protocol, reactor
from twisted.python import log
import sys

import api
import logwatch_config as config

class TailProcessProtocol (protocol.ProcessProtocol) :
    def __init__ (self, module, name, filters) :
        self.module = module
        self.name = name
        self.filters = filters

        self.buf = ""

    def errReceived (self, data) :
        self.module.error("tail for %s: %s" % (self.name, data))

    def outReceived (self, data) :
        data = self.buf + data
        
        while "\n" in data :
            line, data = data.split("\n", 1)
            
            log.msg("Matching line `%s'..." % line)

            for filter in self.filters :
                out = filter.test(line)

                if out :
                    log.msg("\t%s: %s" % (filter.event_type, out))
                    self.module.sendEvent(filter.event_type, out)

        self.buf = data

    def processEnded (self, reason) :
        msg = "tail process for %s quit: %s" % (self.name, reason.getErrorMessage())

        log.err(msg)
        self.module.error(msg)

class LogWatchModule (api.Module) :
    name = "logs"
    version = 0x0001
    
    event_types = [
        "error",
        "sudo",
        "ssh",
    ]
    
    log_files = config.log_files

    log_objs = None

    def handleConnect (self) :
        log.msg("Spawning tail processes...")
        
        self.log_objs = dict()

        for name, file, filters in self.log_files :
            log.msg("\t%s - %s..." % (name, file))

            p = self.log_objs[name] = TailProcessProtocol(self, name, filters)

            reactor.spawnProcess(p, "/usr/bin/tail", ["tail", "-n0", "--follow=name", file])
    
    def error (self, msg) :
        self.sendEvent("error", msg)

if __name__ == '__main__' :
    LogWatchModule().run()