# encoding: utf-8
import re
import sys
from datetime import datetime

class GenericParser(object):
    def __init__(self, fh, errors_only=False): # siia võid anda sys.stdin, gzip.open, open vms file handle tüüpi obj
        self.fh = fh
        self.errors_only = errors_only

    def __iter__(self):
        multiline_message = ""
        log_entry = None
        byte_count = 0
        line_count = 0
        event_count = 0
        for line in self.fh:
            byte_count += len(line) # loenda baite
            line_count += 1

            if not line.strip(): # jäta vahele tühjad read
                continue
            m = re.match(self.RE_LOG_ENTRY, line)
            if m:
                if log_entry:
                    if self.errors_only and not self.is_serious(log_entry):
                        continue
                    stack_trace = "\n".join(multiline_message.split("\n")[1:])
                    event_count += 1
                    row = \
                        datetime.strptime(log_entry.get("timestamp"), self.TIMESTAMP_FORMAT), \
                        log_entry, stack_trace, byte_count, line_count, event_count
                    # See teeb funktsioonist generaatori/iteraatori
                    yield row
                multiline_message = line
                log_entry = m.groupdict()
            else:
                multiline_message += line

class JavaLogParser(GenericParser):
    TIMESTAMP_FORMAT = "%Y-%m-%d %H:%M:%S.%f"
    RE_LOG_ENTRY = "(?P<timestamp>.+?) (?P<severity>[A-Z]+) 1 --- \[(?P<thread>.+)\](?P<class>.+) +: (?P<message>.+)"

    def is_serious(self, log_entry):
        return log_entry.get("severity") == "ERROR"

class ApacheLogParser(GenericParser):
    RE_LOG_ENTRY = "(?P<remote_addr>.+?) - (?P<username>.+?) \[(?P<timestamp>.+?) \+\d\d\d\d\] \"(?P<verb>[A-Z]+) (?P<path>.+) HTTP/1.[01]\" (?P<status>\d+) (?P<size>\d+) \"(?P<referrer>.+?)\" \"(?P<user_agent>.+?)\""
    TIMESTAMP_FORMAT = "%d/%b/%Y:%H:%M:%S"

    def is_serious(self, log_entry):
        return int(log_entry.get("status")) >= 400