# Copyright 2001-2007 by Vinay Sajip. All Rights Reserved.
#
# Permission to use, copy, modify, and distribute this software and its
# documentation for any purpose and without fee is hereby granted,
# provided that the above copyright notice appear in all copies and that
# both that copyright notice and this permission notice appear in
# supporting documentation, and that the name of Vinay Sajip
# not be used in advertising or publicity pertaining to distribution
# of the software without specific, written prior permission.
# VINAY SAJIP DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING
# ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL
# VINAY SAJIP BE LIABLE FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR
# ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER
# IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
# OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.

"""
Additional handlers for the logging package for Python. The core package is
based on PEP 282 and comments thereto in comp.lang.python, and influenced by
Apache's log4j system.

Should work under Python versions >= 1.5.2, except that source line
information is not available unless 'sys._getframe()' is.

Copyright (C) 2001-2007 Vinay Sajip. All Rights Reserved.

To use, simply 'import logging' and log away!
"""

from __pyjamas__ import debugger
from pyjamas.HTTPRequest import HTTPRequest
import logging
import urllib

try:
    import codecs
except ImportError:
    codecs = None

#
# Some constants...
#

DEFAULT_TCP_LOGGING_PORT    = 9020
DEFAULT_UDP_LOGGING_PORT    = 9021
DEFAULT_HTTP_LOGGING_PORT   = 9022
DEFAULT_SOAP_LOGGING_PORT   = 9023
SYSLOG_UDP_PORT             = 514

_MIDNIGHT = 24 * 60 * 60  # number of seconds in a day


class HTTPHandler(logging.Handler):
    """
    A class which sends records to a Web server, using either GET or
    POST semantics.
    """
    def __init__(self, host, url, method="GET"):
        """
        Initialize the instance with the host, the request URL, and the method
        ("GET" or "POST")
        """
        logging.Handler.__init__(self)
        method = method.upper()
        if method not in ["GET", "POST"]:
            raise ValueError, "method must be GET or POST"
        self.host = host
        self.url = url
        self.method = method
        self.httpRequest = HTTPRequest()

    def onCompletion(self, response):
        pass

    def onError(self, repsonse, status):
        pass

    def mapLogRecord(self, record):
        """
        Default implementation of mapping the log record into a dict
        that is sent as the CGI data. Overwrite in your class.
        Contributed by Franz  Glasner.
        """
        return record.toDict()

    def emit(self, record):
        """
        Emit a record.

        Send the record to the Web server as an URL-encoded dictionary
        """
        try:
            host = self.host
            url = self.url
            data = urllib.urlencode(self.mapLogRecord(record))
            if self.method == "GET":
                if (url.find('?') >= 0):
                    sep = '&'
                else:
                    sep = '?'
                url = url + "%c%s" % (sep, data)
            # support multiple hosts on one IP address...
            # need to strip optional :port from host, if present
            i = host.find(":")
            if i >= 0:
                host = host[:i]
            headers = {}
            headers["Host"] = host
            if self.method == "POST":
                self.httpRequest.asyncPost(url, data, self, 
                    content_type="application/x-www-form-urlencoded",
                    headers=headers)
            else:
                self.httpRequest.asyncGet(url, self)
        except:
            self.handleError(record)

class BufferingHandler(logging.Handler):
    """
  A handler class which buffers logging records in memory. Whenever each
  record is added to the buffer, a check is made to see if the buffer should
  be flushed. If it should, then flush() is expected to do what's needed.
    """
    def __init__(self, capacity):
        """
        Initialize the handler with the buffer size.
        """
        logging.Handler.__init__(self)
        self.capacity = capacity
        self.buffer = []

    def shouldFlush(self, record):
        """
        Should the handler flush its buffer?

        Returns true if the buffer is up to capacity. This method can be
        overridden to implement custom flushing strategies.
        """
        return (len(self.buffer) >= self.capacity)

    def emit(self, record):
        """
        Emit a record.

        Append the record. If shouldFlush() tells us to, call flush() to process
        the buffer.
        """
        self.buffer.append(record)
        if self.shouldFlush(record):
            self.flush()

    def flush(self):
        """
        Override to implement custom flushing behaviour.

        This version just zaps the buffer to empty.
        """
        self.buffer = []

    def close(self):
        """
        Close the handler.

        This version just flushes and chains to the parent class' close().
        """
        self.flush()
        logging.Handler.close(self)

class MemoryHandler(BufferingHandler):
    """
    A handler class which buffers logging records in memory, periodically
    flushing them to a target handler. Flushing occurs whenever the buffer
    is full, or when an event of a certain severity or greater is seen.
    """
    def __init__(self, capacity, flushLevel=logging.ERROR, target=None):
        """
        Initialize the handler with the buffer size, the level at which
        flushing should occur and an optional target.

        Note that without a target being set either here or via setTarget(),
        a MemoryHandler is no use to anyone!
        """
        BufferingHandler.__init__(self, capacity)
        self.flushLevel = flushLevel
        self.target = target

    def shouldFlush(self, record):
        """
        Check for buffer full or a record at the flushLevel or higher.
        """
        return (len(self.buffer) >= self.capacity) or \
                (record.levelno >= self.flushLevel)

    def setTarget(self, target):
        """
        Set the target handler for this handler.
        """
        self.target = target

    def flush(self):
        """
        For a MemoryHandler, flushing means just sending the buffered
        records to the target, if there is one. Override if you want
        different behaviour.
        """
        if self.target:
            for record in self.buffer:
                self.target.handle(record)
            self.buffer = []

    def close(self):
        """
        Flush, set the target to None and lose the buffer.
        """
        self.flush()
        self.target = None
        BufferingHandler.close(self)
