#!/usr/bin/env python
#
# crashlytics.py -- summarise multiple `DiagnosticReports` `.crash` files
#
# Usage:
#
#   ./crashlytics.py ~/Library/Logs/DiagnosticReports/lmms_*
#
# Author: <follower@rancidbacon.com>
# Version: 0.1
# License: GPL3+
#
# See also:
#   * <https://developer.apple.com/library/content/technotes/tn2151/_index.html>
#   * <https://developer.apple.com/library/content/documentation/IDEs/Conceptual/AppDistributionGuide/AnalyzingCrashReports/AnalyzingCrashReports.html>
#   * <https://discussions.apple.com/thread/5070949?tstart=0> "Q: Can I decode the crash data?"
#   * <http://www.sealiesoftware.com/blog/archive/2008/09/22/objc_explain_So_you_crashed_in_objc_msgSend.html>
#   * <https://red-sweater.com/blog/860/crash-reporter-roundup>
#

import sys

class Backtrace(object):
    """
    """

    def __init__(self, lines):
        """
        """
        self.lines = lines


class CrashReport(object):
    """
    """

    def __init__(self, file_path):
        """
        """
        self.info = {}
        self.backtraces = []

        self.file_path = file_path

        self._file = open(file_path, "r")

        self._parse_header()

        self._skip_to_backtraces()

        # TODO: Don't be so hacky?
        if self.info["Crashed Thread"].startswith("0"):
            self.backtraces.append(self._parse_backtrace())

        # TODO: Parse other backtraces?
        # TODO: Parse end of file?


    def _parse_header(self):
        """
        Parses "Header" and "Exception Information" sections.
        """
        for line in self._file:
            #print line,

            line = line.rstrip()
            if line:
                key, value = line.split(":", 1)
                self.info[key] = value.lstrip()

                if key == "Report Version":
                    # TODO: Panic on unknown report version?
                    pass

                if key == "Exception Codes":
                    break


    def _skip_to_backtraces(self):
        """
        Skips the "Additional Diagnostic Information" section.
        """
        for line in self._file:
            #print line,
            if line.startswith("Thread 0"):
                # TODO: Push back?
                break


    def _parse_backtrace(self):
        """
        """
        lines = []
        for line in self._file:
            line = line.rstrip()

            #print line

            if not line:
                break

            lines.append(line)

        return Backtrace(lines)


if __name__ == "__main__":
    reports = []
    for crash_report_filename in sys.argv[1:]:
        #print crash_report_filename

        reports.append(CrashReport(crash_report_filename))

    #import pprint
    #pprint.pprint(reports[0].info)

    print "Total reports processed: ", len(reports)
    print

    from collections import defaultdict

    reports_by_type = defaultdict(list)
    for report in reports:
        reports_by_type[report.info["Exception Type"]].append(report)

    for exception_type, report_group in reports_by_type.items():
        print
        print exception_type, "| Occurrences: ", len(report_group)
        for report in report_group:
            print
            print "  ", report.info["Exception Codes"]
            for line_number in range(5):
                print "      ", report.backtraces[0].lines[line_number]