#!/usr/bin/env python

import getopt
import json
import os
import struct
import sys

OP_OPEN, OP_CLOSE, OP_WRITE, OP_EXEC = 1, 2, 3, 4
TYPE_INPUT, TYPE_OUTPUT, TYPE_INTERACT = 1, 2, 3

COLOR_INTERACT = "\033[36m"
COLOR_INPUT = "\033[33m"
COLOR_RESET = "\033[0m"


def playlog(fd, settings):
    thelog = {}
    thelog["version"] = 1
    thelog["width"] = 80
    thelog["height"] = 24
    thelog["duration"] = 0.0
    thelog["command"] = "/bin/bash"
    thelog["title"] = "Cowrie Recording"
    theenv = {}
    theenv["TERM"] = "xterm256-color"
    theenv["SHELL"] = "/bin/bash"
    thelog["env"] = theenv
    stdout = []
    thelog["stdout"] = stdout

    ssize = struct.calcsize("<iLiiLL")

    currtty, prevtime, prefdir = 0, 0, 0
    sleeptime = 0.0

    color = None

    while 1:
        try:
            (op, tty, length, dir, sec, usec) = struct.unpack("<iLiiLL", fd.read(ssize))
            data = fd.read(length)
        except struct.error:
            break

        if currtty == 0:
            currtty = tty

        if str(tty) == str(currtty) and op == OP_WRITE:
            # the first stream seen is considered 'output'
            if prefdir == 0:
                prefdir = dir
            if dir == TYPE_INTERACT:
                color = COLOR_INTERACT
            elif dir == TYPE_INPUT:
                color = COLOR_INPUT
            if dir == prefdir:
                curtime = float(sec) + float(usec) / 1000000
                if prevtime != 0:
                    sleeptime = curtime - prevtime
                prevtime = curtime
                if settings["colorify"] and color:
                    sys.stdout.write(color)

                # rtrox: While playback works properly
                #        with the asciinema client, upload
                #        causes mangling of the data due to
                #        newlines being misinterpreted without
                #        carriage returns.
                data = data.replace(b"\n", b"\r\n").decode("UTF-8")

                thedata = [sleeptime, data]
                thelog["duration"] += sleeptime
                stdout.append(thedata)

                if settings["colorify"] and color:
                    sys.stdout.write(COLOR_RESET)
                    color = None

        elif str(tty) == str(currtty) and op == OP_CLOSE:
            break

    if settings["output"] == "":
        json.dump(thelog, sys.stdout, indent=4)
    else:
        with open(settings["output"], "w") as outfp:
            json.dump(thelog, outfp, indent=4)


def help(verbose=False):
    print(
        "usage: %s [-c] [-o output] <tty-log-file> <tty-log-file>..."
        % os.path.basename(sys.argv[0])
    )

    if verbose:
        print(
            "  -c             colorify the output based on what streams are being received"
        )
        print("  -h             display this help")
        print("  -o             write to the specified output file")


if __name__ == "__main__":
    settings = {"colorify": 0, "output": ""}

    try:
        optlist, args = getopt.getopt(sys.argv[1:], "hco:")
    except getopt.GetoptError as error:
        sys.stderr.write(f"{sys.argv[0]}: {error}\n")
        help()
        sys.exit(1)

    for o, a in optlist:
        if o == "-h":
            help()
        if o == "-c":
            settings["colorify"] = True
        if o == "-o":
            settings["output"] = a

    if len(args) < 1:
        help()
        sys.exit(2)

    for logfile in args:
        try:
            logfd = open(logfile, "rb")
            playlog(logfd, settings)
        except OSError as e:
            sys.stderr.write(f"{sys.argv[0]}: {e}\n")