#!/usr/bin/env node
/**
 * Copyright 2016 Trent Mick. All rights reserved.
 * Copyright 2016 Joyent Inc. All rights reserved.
 *
 * bunyan -- filter and pretty-print Bunyan log files (line-delimited JSON)
 *
 * See <https://github.com/trentm/node-bunyan>.
 *
 * -*- mode: js -*-
 * vim: expandtab:ts=4:sw=4
 */

var VERSION = '1.8.1';

var p = console.log;
var util = require('util');
var pathlib = require('path');
var vm = require('vm');
var http = require('http');
var fs = require('fs');
var warn = console.warn;
var child_process = require('child_process'),
    spawn = child_process.spawn,
    exec = child_process.exec,
    execFile = child_process.execFile;
var assert = require('assert');

try {
    var moment = require('moment');
} catch (e) {
    moment = null;
}


//---- globals and constants

var nodeVer = process.versions.node.split('.').map(Number);
var nodeSpawnSupportsStdio = (nodeVer[0] > 0 || nodeVer[1] >= 8);

// Internal debug logging via `console.warn`.
var _DEBUG = false;

// Output modes.
var OM_LONG = 1;
var OM_JSON = 2;
var OM_INSPECT = 3;
var OM_SIMPLE = 4;
var OM_SHORT = 5;
var OM_BUNYAN = 6;
var OM_FROM_NAME = {
    'long': OM_LONG,
    'paul': OM_LONG,  /* backward compat */
    'json': OM_JSON,
    'inspect': OM_INSPECT,
    'simple': OM_SIMPLE,
    'short': OM_SHORT,
    'bunyan': OM_BUNYAN
};


// Levels
var TRACE = 10;
var DEBUG = 20;
var INFO = 30;
var WARN = 40;
var ERROR = 50;
var FATAL = 60;

var levelFromName = {
    'trace': TRACE,
    'debug': DEBUG,
    'info': INFO,
    'warn': WARN,
    'error': ERROR,
    'fatal': FATAL
};
var nameFromLevel = {};
var upperNameFromLevel = {};
var upperPaddedNameFromLevel = {};
Object.keys(levelFromName).forEach(function (name) {
    var lvl = levelFromName[name];
    nameFromLevel[lvl] = name;
    upperNameFromLevel[lvl] = name.toUpperCase();
    upperPaddedNameFromLevel[lvl] = (
        name.length === 4 ? ' ' : '') + name.toUpperCase();
});


// Display time formats.
var TIME_UTC = 1;  // the default, bunyan's native format
var TIME_LOCAL = 2;

// Timezone formats: output format -> momentjs format string
var TIMEZONE_UTC_FORMATS = {
    long:  '[[]YYYY-MM-DD[T]HH:mm:ss.SSS[Z][]]',
    short: 'HH:mm:ss.SSS[Z]'
};
var TIMEZONE_LOCAL_FORMATS = {
    long:  '[[]YYYY-MM-DD[T]HH:mm:ss.SSSZ[]]',
    short: 'HH:mm:ss.SSS'
};


// The current raw input line being processed. Used for `uncaughtException`.
var currLine = null;

// Child dtrace process, if any. Used for signal-handling.
var child = null;

// Whether ANSI codes are being used. Used for signal-handling.
var usingAnsiCodes = false;

// Used to tell the 'uncaughtException' handler that '-c CODE' is being used.
var gUsingConditionOpts = false;

// Pager child process, and output stream to which to write.
var pager = null;
var stdout = process.stdout;

// Whether we are reading from stdin.
var readingStdin = false;



//---- support functions

function getVersion() {
    return VERSION;
}


var format = util.format;
if (!format) {
    /* BEGIN JSSTYLED */
    // If not node 0.6, then use its `util.format`:
    // <https://github.com/joyent/node/blob/master/lib/util.js#L22>:
    var inspect = util.inspect;
    var formatRegExp = /%[sdj%]/g;
    format = function format(f) {
        if (typeof f !== 'string') {
            var objects = [];
            for (var i = 0; i < arguments.length; i++) {
                objects.push(inspect(arguments[i]));
            }
            return objects.join(' ');
        }

        var i = 1;
        var args = arguments;
        var len = args.length;
        var str = String(f).replace(formatRegExp, function (x) {
            if (i >= len)
                return x;
            switch (x) {
                case '%s': return String(args[i++]);
                case '%d': return Number(args[i++]);
                case '%j': return JSON.stringify(args[i++]);
                case '%%': return '%';
                default:
                    return x;
            }
        });
        for (var x = args[i]; i < len; x = args[++i]) {
            if (x === null || typeof x !== 'object') {
                str += ' ' + x;
            } else {
                str += ' ' + inspect(x);
            }
        }
        return str;
    };
    /* END JSSTYLED */
}

function indent(s) {
    return '    ' + s.split(/\r?\n/).join('\n    ');
}

function objCopy(obj) {
    if (obj === null) {
        return null;
    } else if (Array.isArray(obj)) {
        return obj.slice();
    } else {
        var copy = {};
        Object.keys(obj).forEach(function (k) {
            copy[k] = obj[k];
        });
        return copy;
    }
}

function printHelp() {
    /* BEGIN JSSTYLED */
    p('Usage:');
    p('  bunyan [OPTIONS] [FILE ...]');
    p('  ... | bunyan [OPTIONS]');
    p('  bunyan [OPTIONS] -p PID');
    p('');
    p('Filter and pretty-print Bunyan log file content.');
    p('');
    p('General options:');
    p('  -h, --help    print this help info and exit');
    p('  --version     print version of this command and exit');
    p('');
    p('Runtime log snooping (via DTrace, only on supported platforms):');
    p('  -p PID        Process bunyan:log-* probes from the process');
    p('                with the given PID. Can be used multiple times,');
    p('                or specify all processes with "*", or a set of');
    p('                processes whose command & args match a pattern');
    p('                with "-p NAME".');
    p('');
    p('Filtering options:');
    p('  -l, --level LEVEL');
    p('                Only show messages at or above the specified level.');
    p('                You can specify level *names* or the internal numeric');
    p('                values.');
    p('  -c, --condition CONDITION');
    p('                Run each log message through the condition and');
    p('                only show those that return truish. E.g.:');
    p('                    -c \'this.pid == 123\'');
    p('                    -c \'this.level == DEBUG\'');
    p('                    -c \'this.msg.indexOf("boom") != -1\'');
    p('                "CONDITION" must be legal JS code. `this` holds');
    p('                the log record. The TRACE, DEBUG, ... FATAL values');
    p('                are defined to help with comparing `this.level`.');
    p('  --strict      Suppress all but legal Bunyan JSON log lines. By default');
    p('                non-JSON, and non-Bunyan lines are passed through.');
    p('');
    p('Output options:');
    p('  --pager       Pipe output into `less` (or $PAGER if set), if');
    p('                stdout is a TTY. This overrides $BUNYAN_NO_PAGER.');
    p('                Note: Paging is only supported on node >=0.8.');
    p('  --no-pager    Do not pipe output into a pager.');
    p('  --color       Colorize output. Defaults to try if output');
    p('                stream is a TTY.');
    p('  --no-color    Force no coloring (e.g. terminal doesn\'t support it)');
    p('  -o, --output MODE');
    p('                Specify an output mode/format. One of');
    p('                  long: (the default) pretty');
    p('                  json: JSON output, 2-space indent');
    p('                  json-N: JSON output, N-space indent, e.g. "json-4"');
    p('                  bunyan: 0 indented JSON, bunyan\'s native format');
    p('                  inspect: node.js `util.inspect` output');
    p('                  short: like "long", but more concise');
    p('  -j            shortcut for `-o json`');
    p('  -0            shortcut for `-o bunyan`');
    p('  -L, --time local');
    p('                Display time field in local time, rather than UTC.');
    p('');
    p('Environment Variables:');
    p('  BUNYAN_NO_COLOR    Set to a non-empty value to force no output ');
    p('                     coloring. See "--no-color".');
    p('  BUNYAN_NO_PAGER    Disable piping output to a pager. ');
    p('                     See "--no-pager".');
    p('');
    p('See <https://github.com/trentm/node-bunyan> for more complete docs.');
    p('Please report bugs to <https://github.com/trentm/node-bunyan/issues>.');
    /* END JSSTYLED */
}

/*
 * If the user specifies multiple input sources, we want to print out records
 * from all sources in a single, chronologically ordered stream.  To do this
 * efficiently, we first assume that all records within each source are ordered
 * already, so we need only keep track of the next record in each source and
 * the time of the last record emitted.  To avoid excess memory usage, we
 * pause() streams that are ahead of others.
 *
 * 'streams' is an object indexed by source name (file name) which specifies:
 *
 *    stream        Actual stream object, so that we can pause and resume it.
 *
 *    records       Array of log records we've read, but not yet emitted.  Each
 *                  record includes 'line' (the raw line), 'rec' (the JSON
 *                  record), and 'time' (the parsed time value).
 *
 *    done          Whether the stream has any more records to emit.
 */
var streams = {};

function gotRecord(file, line, rec, opts, stylize)
{
    var time = new Date(rec.time);

    streams[file]['records'].push({ line: line, rec: rec, time: time });
    emitNextRecord(opts, stylize);
}

function filterRecord(rec, opts)
{
    if (opts.level && rec.level < opts.level) {
        return false;
    }

    if (opts.condFuncs) {
        var recCopy = objCopy(rec);
        for (var i = 0; i < opts.condFuncs.length; i++) {
            var pass = opts.condFuncs[i].call(recCopy);
            if (!pass)
                return false;
        }
    } else if (opts.condVm) {
        for (var i = 0; i < opts.condVm.length; i++) {
            var pass = opts.condVm[i].runInNewContext(rec);
            if (!pass)
                return false;
        }
    }

    return true;
}

function emitNextRecord(opts, stylize)
{
    var ofile, ready, minfile, rec;

    for (;;) {
        /*
         * Take a first pass through the input streams to see if we have a
         * record from all of them.  If not, we'll pause any streams for
         * which we do already have a record (to avoid consuming excess
         * memory) and then wait until we have records from the others
         * before emitting the next record.
         *
         * As part of the same pass, we look for the earliest record
         * we have not yet emitted.
         */
        minfile = undefined;
        ready = true;
        for (ofile in streams) {

            if (streams[ofile].stream === null ||
                (!streams[ofile].done && streams[ofile].records.length === 0)) {
                ready = false;
                break;
            }

            if (streams[ofile].records.length > 0 &&
                (minfile === undefined ||
                    streams[minfile].records[0].time >
                        streams[ofile].records[0].time)) {
                minfile = ofile;
            }
        }

        if (!ready || minfile === undefined) {
            for (ofile in streams) {
                if (!streams[ofile].stream || streams[ofile].done)
                    continue;

                if (streams[ofile].records.length > 0) {
                    if (!streams[ofile].paused) {
                        streams[ofile].paused = true;
                        streams[ofile].stream.pause();
                    }
                } else if (streams[ofile].paused) {
                    streams[ofile].paused = false;
                    streams[ofile].stream.resume();
                }
            }

            return;
        }

        /*
         * Emit the next record for 'minfile', and invoke ourselves again to
         * make sure we emit as many records as we can right now.
         */
        rec = streams[minfile].records.shift();
        emitRecord(rec.rec, rec.line, opts, stylize);
    }
}

/**
 * Return a function for the given JS code that returns.
 *
 * If no 'return' in the given javascript snippet, then assume we are a single
 * statement and wrap in 'return (...)'. This is for convenience for short
 * '-c ...' snippets.
 */
function funcWithReturnFromSnippet(js) {
    // auto-"return"
    if (js.indexOf('return') === -1) {
        if (js.substring(js.length - 1) === ';') {
            js = js.substring(0, js.length - 1);
        }
        js = 'return (' + js + ')';
    }

    // Expose level definitions to condition func context
    var varDefs = [];
    Object.keys(upperNameFromLevel).forEach(function (lvl) {
        varDefs.push(format('var %s = %d;',
                upperNameFromLevel[lvl], lvl));
    });
    varDefs = varDefs.join('\n') + '\n';

    return (new Function(varDefs + js));
}

/**
 * Parse the command-line options and arguments into an object.
 *
 *    {
 *      'args': [...]       // arguments
 *      'help': true,       // true if '-h' option given
 *       // etc.
 *    }
 *
 * @return {Object} The parsed options. `.args` is the argument list.
 * @throws {Error} If there is an error parsing argv.
 */
function parseArgv(argv) {
    var parsed = {
        args: [],
        help: false,
        color: null,
        paginate: null,
        outputMode: OM_LONG,
        jsonIndent: 2,
        level: null,
        strict: false,
        pids: null,
        pidsType: null,
        timeFormat: TIME_UTC  // one of the TIME_ constants
    };

    // Turn '-iH' into '-i -H', except for argument-accepting options.
    var args = argv.slice(2);  // drop ['node', 'scriptname']
    var newArgs = [];
    var optTakesArg = {'d': true, 'o': true, 'c': true, 'l': true, 'p': true};
    for (var i = 0; i < args.length; i++) {
        if (args[i].charAt(0) === '-' && args[i].charAt(1) !== '-' &&
            args[i].length > 2)
        {
            var splitOpts = args[i].slice(1).split('');
            for (var j = 0; j < splitOpts.length; j++) {
                newArgs.push('-' + splitOpts[j]);
                if (optTakesArg[splitOpts[j]]) {
                    var optArg = splitOpts.slice(j+1).join('');
                    if (optArg.length) {
                        newArgs.push(optArg);
                    }
                    break;
                }
            }
        } else {
            newArgs.push(args[i]);
        }
    }
    args = newArgs;

    // Expose level definitions to condition vm context
    var condDefines = [];
    Object.keys(upperNameFromLevel).forEach(function (lvl) {
        condDefines.push(
            format('Object.prototype.%s = %s;', upperNameFromLevel[lvl], lvl));
    });
    condDefines = condDefines.join('\n') + '\n';

    var endOfOptions = false;
    while (args.length > 0) {
        var arg = args.shift();
        switch (arg) {
            case '--':
                endOfOptions = true;
                break;
            case '-h': // display help and exit
            case '--help':
                parsed.help = true;
                break;
            case '--version':
                parsed.version = true;
                break;
            case '--strict':
                parsed.strict = true;
                break;
            case '--color':
                parsed.color = true;
                break;
            case '--no-color':
                parsed.color = false;
                break;
            case '--pager':
                parsed.paginate = true;
                break;
            case '--no-pager':
                parsed.paginate = false;
                break;
            case '-o':
            case '--output':
                var name = args.shift();
                var idx = name.lastIndexOf('-');
                if (idx !== -1) {
                    var indentation = Number(name.slice(idx+1));
                    if (! isNaN(indentation)) {
                        parsed.jsonIndent = indentation;
                        name = name.slice(0, idx);
                    }
                }
                parsed.outputMode = OM_FROM_NAME[name];
                if (parsed.outputMode === undefined) {
                    throw new Error('unknown output mode: "'+name+'"');
                }
                break;
            case '-j': // output with JSON.stringify
                parsed.outputMode = OM_JSON;
                break;
            case '-0':
                parsed.outputMode = OM_BUNYAN;
                break;
            case '-L':
                parsed.timeFormat = TIME_LOCAL;
                if (!moment) {
                    throw new Error(
                        'could not find moment package required for "-L"');
                }
                break;
            case '--time':
                var timeArg = args.shift();
                switch (timeArg) {
                case 'utc':
                    parsed.timeFormat = TIME_UTC;
                    break
                case 'local':
                    parsed.timeFormat = TIME_LOCAL;
                    if (!moment) {
                        throw new Error('could not find moment package '
                            + 'required for "--time=local"');
                    }
                    break
                case undefined:
                    throw new Error('missing argument to "--time"');
                default:
                    throw new Error(format('invalid time format: "%s"',
                        timeArg));
                }
                break;
            case '-p':
                if (!parsed.pids) {
                    parsed.pids = [];
                }
                var pidArg = args.shift();
                var pid = +(pidArg);
                if (!isNaN(pid) || pidArg === '*') {
                    if (parsed.pidsType && parsed.pidsType !== 'num') {
                        throw new Error(format('cannot mix PID name and '
                            + 'number arguments: "%s"', pidArg));
                    }
                    parsed.pidsType = 'num';
                    if (!parsed.pids) {
                        parsed.pids = [];
                    }
                    parsed.pids.push(isNaN(pid) ? pidArg : pid);
                } else {
                    if (parsed.pidsType && parsed.pidsType !== 'name') {
                        throw new Error(format('cannot mix PID name and '
                            + 'number arguments: "%s"', pidArg));
                    }
                    parsed.pidsType = 'name';
                    parsed.pids = pidArg;
                }
                break;
            case '-l':
            case '--level':
                var levelArg = args.shift();
                var level = +(levelArg);
                if (isNaN(level)) {
                    level = +levelFromName[levelArg.toLowerCase()];
                }
                if (isNaN(level)) {
                    throw new Error('unknown level value: "'+levelArg+'"');
                }
                parsed.level = level;
                break;
            case '-c':
            case '--condition':
                gUsingConditionOpts = true;
                var condition = args.shift();
                if (Boolean(process.env.BUNYAN_EXEC &&
                    process.env.BUNYAN_EXEC === 'vm'))
                {
                    parsed.condVm = parsed.condVm || [];
                    var scriptName = 'bunyan-condition-'+parsed.condVm.length;
                    var code = condDefines + condition;
                    var script;
                    try {
                        script = vm.createScript(code, scriptName);
                    } catch (complErr) {
                        throw new Error(format('illegal CONDITION code: %s\n'
                            + '  CONDITION script:\n'
                            + '%s\n'
                            + '  Error:\n'
                            + '%s',
                            complErr, indent(code), indent(complErr.stack)));
                    }

                    // Ensure this is a reasonably safe CONDITION.
                    try {
                        script.runInNewContext(minValidRecord);
                    } catch (condErr) {
                        throw new Error(format(
                            /* JSSTYLED */
                            'CONDITION code cannot safely filter a minimal Bunyan log record\n'
                            + '  CONDITION script:\n'
                            + '%s\n'
                            + '  Minimal Bunyan log record:\n'
                            + '%s\n'
                            + '  Filter error:\n'
                            + '%s',
                            indent(code),
                            indent(JSON.stringify(minValidRecord, null, 2)),
                            indent(condErr.stack)
                            ));
                    }
                    parsed.condVm.push(script);
                } else  {
                    parsed.condFuncs = parsed.condFuncs || [];
                    parsed.condFuncs.push(funcWithReturnFromSnippet(condition));
                }
                break;
            default: // arguments
                if (!endOfOptions && arg.length > 0 && arg[0] === '-') {
                    throw new Error('unknown option "'+arg+'"');
                }
                parsed.args.push(arg);
                break;
        }
    }
    //TODO: '--' handling and error on a first arg that looks like an option.

    return parsed;
}


function isInteger(s) {
    return (s.search(/^-?[0-9]+$/) == 0);
}


// http://en.wikipedia.org/wiki/ANSI_escape_code#graphics
// Suggested colors (some are unreadable in common cases):
// - Good: cyan, yellow (limited use), bold, green, magenta, red
// - Bad: blue (not visible on cmd.exe), grey (same color as background on
//   Solarized Dark theme from <https://github.com/altercation/solarized>, see
//   issue #160)
var colors = {
    'bold' : [1, 22],
    'italic' : [3, 23],
    'underline' : [4, 24],
    'inverse' : [7, 27],
    'white' : [37, 39],
    'grey' : [90, 39],
    'black' : [30, 39],
    'blue' : [34, 39],
    'cyan' : [36, 39],
    'green' : [32, 39],
    'magenta' : [35, 39],
    'red' : [31, 39],
    'yellow' : [33, 39]
};

function stylizeWithColor(str, color) {
    if (!str)
        return '';
    var codes = colors[color];
    if (codes) {
        return '\033[' + codes[0] + 'm' + str +
                     '\033[' + codes[1] + 'm';
    } else {
        return str;
    }
}

function stylizeWithoutColor(str, color) {
    return str;
}


/**
 * Is this a valid Bunyan log record.
 */
function isValidRecord(rec) {
    if (rec.v == null ||
            rec.level == null ||
            rec.name == null ||
            rec.hostname == null ||
            rec.pid == null ||
            rec.time == null ||
            rec.msg == null) {
        // Not valid Bunyan log.
        return false;
    } else {
        return true;
    }
}
var minValidRecord = {
    v: 0,   //TODO: get this from bunyan.LOG_VERSION
    level: INFO,
    name: 'name',
    hostname: 'hostname',
    pid: 123,
    time: Date.now(),
    msg: 'msg'
};


/**
 * Parses the given log line and either emits it right away (for invalid
 * records) or enqueues it for emitting later when it's the next line to show.
 */
function handleLogLine(file, line, opts, stylize) {
    currLine = line; // intentionally global

    // Emit non-JSON lines immediately.
    var rec;
    if (!line) {
        if (!opts.strict) emit(line + '\n');
        return;
    } else if (line[0] !== '{') {
        if (!opts.strict) emit(line + '\n');  // not JSON
        return;
    } else {
        try {
            rec = JSON.parse(line);
        } catch (e) {
            if (!opts.strict) emit(line + '\n');
            return;
        }
    }

    if (!isValidRecord(rec)) {
        if (!opts.strict) emit(line + '\n');
        return;
    }

    if (!filterRecord(rec, opts))
        return;

    if (file === null)
        return emitRecord(rec, line, opts, stylize);

    return gotRecord(file, line, rec, opts, stylize);
}

/**
 * Print out a single result, considering input options.
 */
function emitRecord(rec, line, opts, stylize) {
    var short = false;

    switch (opts.outputMode) {
    case OM_SHORT:
        short = true;
        /* jsl:fall-thru */

    case OM_LONG:
        //    [time] LEVEL: name[/comp]/pid on hostname (src): msg* (extras...)
        //        msg*
        //        --
        //        long and multi-line extras
        //        ...
        // If 'msg' is single-line, then it goes in the top line.
        // If 'req', show the request.
        // If 'res', show the response.
        // If 'err' and 'err.stack' then show that.
        if (!isValidRecord(rec)) {
            return emit(line + '\n');
        }

        delete rec.v;

        // Time.
        var time;
        if (!short && opts.timeFormat === TIME_UTC) {
            // Fast default path: We assume the raw `rec.time` is a UTC time
            // in ISO 8601 format (per spec).
            time = '[' + rec.time + ']';
        } else if (!moment && opts.timeFormat === TIME_UTC) {
            // Don't require momentjs install, as long as not using TIME_LOCAL.
            time = rec.time.substr(11);
        } else {
            var tzFormat;
            var moTime = moment(rec.time);
            switch (opts.timeFormat) {
            case TIME_UTC:
                tzFormat = TIMEZONE_UTC_FORMATS[short ? 'short' : 'long'];
                moTime.utc();
                break;
            case TIME_LOCAL:
                tzFormat = TIMEZONE_LOCAL_FORMATS[short ? 'short' : 'long'];
                break;
            default:
                throw new Error('unexpected timeFormat: ' + opts.timeFormat);
            };
            time = moTime.format(tzFormat);
        }
        time = stylize(time, 'XXX');
        delete rec.time;

        var nameStr = rec.name;
        delete rec.name;

        if (rec.component) {
            nameStr += '/' + rec.component;
        }
        delete rec.component;

        if (!short)
            nameStr += '/' + rec.pid;
        delete rec.pid;

        var level = (upperPaddedNameFromLevel[rec.level] || 'LVL' + rec.level);
        if (opts.color) {
            var colorFromLevel = {
                10: 'white',    // TRACE
                20: 'yellow',   // DEBUG
                30: 'cyan',     // INFO
                40: 'magenta',  // WARN
                50: 'red',      // ERROR
                60: 'inverse',  // FATAL
            };
            level = stylize(level, colorFromLevel[rec.level]);
        }
        delete rec.level;

        var src = '';
        if (rec.src && rec.src.file) {
            var s = rec.src;
            if (s.func) {
                src = format(' (%s:%d in %s)', s.file, s.line, s.func);
            } else {
                src = format(' (%s:%d)', s.file, s.line);
            }
            src = stylize(src, 'green');
        }
        delete rec.src;

        var hostname = rec.hostname;
        delete rec.hostname;

        var extras = [];
        var details = [];

        if (rec.req_id) {
            extras.push('req_id=' + rec.req_id);
        }
        delete rec.req_id;

        var onelineMsg;
        if (rec.msg.indexOf('\n') !== -1) {
            onelineMsg = '';
            details.push(indent(stylize(rec.msg, 'cyan')));
        } else {
            onelineMsg = ' ' + stylize(rec.msg, 'cyan');
        }
        delete rec.msg;

        if (rec.req && typeof (rec.req) === 'object') {
            var req = rec.req;
            delete rec.req;
            var headers = req.headers;
            if (!headers) {
                headers = '';
            } else if (typeof (headers) === 'string') {
                headers = '\n' + headers;
            } else if (typeof (headers) === 'object') {
                headers = '\n' + Object.keys(headers).map(function (h) {
                    return h + ': ' + headers[h];
                }).join('\n');
            }
            var s = format('%s %s HTTP/%s%s', req.method,
                req.url,
                req.httpVersion || '1.1',
                headers
            );
            delete req.url;
            delete req.method;
            delete req.httpVersion;
            delete req.headers;
            if (req.body) {
                s += '\n\n' + (typeof (req.body) === 'object'
                    ? JSON.stringify(req.body, null, 2) : req.body);
                delete req.body;
            }
            if (req.trailers && Object.keys(req.trailers) > 0) {
                s += '\n' + Object.keys(req.trailers).map(function (t) {
                    return t + ': ' + req.trailers[t];
                }).join('\n');
            }
            delete req.trailers;
            details.push(indent(s));
            // E.g. for extra 'foo' field on 'req', add 'req.foo' at
            // top-level. This *does* have the potential to stomp on a
            // literal 'req.foo' key.
            Object.keys(req).forEach(function (k) {
                rec['req.' + k] = req[k];
            })
        }

        if (rec.client_req && typeof (rec.client_req) === 'object') {
            var client_req = rec.client_req;
            delete rec.client_req;
            var headers = client_req.headers;
            var hostHeaderLine = '';
            var s = '';
            if (client_req.address) {
                hostHeaderLine = '\nHost: ' + client_req.address;
                if (client_req.port)
                    hostHeaderLine += ':' + client_req.port;
            }
            delete client_req.headers;
            delete client_req.address;
            delete client_req.port;
            s += format('%s %s HTTP/%s%s%s', client_req.method,
                client_req.url,
                client_req.httpVersion || '1.1',
                hostHeaderLine,
                (headers ?
                    '\n' + Object.keys(headers).map(
                        function (h) {
                            return h + ': ' + headers[h];
                        }).join('\n') :
                    ''));
            delete client_req.method;
            delete client_req.url;
            delete client_req.httpVersion;
            if (client_req.body) {
                s += '\n\n' + (typeof (client_req.body) === 'object' ?
                    JSON.stringify(client_req.body, null, 2) :
                    client_req.body);
                delete client_req.body;
            }
            // E.g. for extra 'foo' field on 'client_req', add
            // 'client_req.foo' at top-level. This *does* have the potential
            // to stomp on a literal 'client_req.foo' key.
            Object.keys(client_req).forEach(function (k) {
                rec['client_req.' + k] = client_req[k];
            })
            details.push(indent(s));
        }

        function _res(res) {
            var s = '';
            if (res.statusCode !== undefined) {
                s += format('HTTP/1.1 %s %s\n', res.statusCode,
                    http.STATUS_CODES[res.statusCode]);
                delete res.statusCode;
            }
            // Handle `res.header` or `res.headers` as either a string or
            // and object of header key/value pairs. Prefer `res.header` if set
            // (TODO: Why? I don't recall. Typical of restify serializer?
            // Typical JSON.stringify of a core node HttpResponse?)
            var headerTypes = {string: true, object: true};
            var headers;
            if (res.header && headerTypes[typeof (res.header)]) {
                headers = res.header;
                delete res.header;
            } else if (res.headers && headerTypes[typeof (res.headers)]) {
                headers = res.headers;
                delete res.headers;
            }
            if (headers === undefined) {
                /* pass through */
            } else if (typeof (headers) === 'string') {
                s += headers.trimRight();
            } else {
                s += Object.keys(headers).map(
                    function (h) { return h + ': ' + headers[h]; }).join('\n');
            }
            if (res.body !== undefined) {
                var body = (typeof (res.body) === 'object'
                    ? JSON.stringify(res.body, null, 2) : res.body);
                if (body.length > 0) { s += '\n\n' + body };
                delete res.body;
            } else {
                s = s.trimRight();
            }
            if (res.trailer) {
                s += '\n' + res.trailer;
            }
            delete res.trailer;
            if (s) {
                details.push(indent(s));
            }
            // E.g. for extra 'foo' field on 'res', add 'res.foo' at
            // top-level. This *does* have the potential to stomp on a
            // literal 'res.foo' key.
            Object.keys(res).forEach(function (k) {
                rec['res.' + k] = res[k];
            });
        }

        if (rec.res && typeof (rec.res) === 'object') {
            _res(rec.res);
            delete rec.res;
        }
        if (rec.client_res && typeof (rec.client_res) === 'object') {
            _res(rec.client_res);
            delete rec.client_res;
        }

        if (rec.err && rec.err.stack) {
            var err = rec.err
            if (typeof (err.stack) !== 'string') {
                details.push(indent(err.stack.toString()));
            } else {
                details.push(indent(err.stack));
            }
            delete err.message;
            delete err.name;
            delete err.stack;
            // E.g. for extra 'foo' field on 'err', add 'err.foo' at
            // top-level. This *does* have the potential to stomp on a
            // literal 'err.foo' key.
            Object.keys(err).forEach(function (k) {
                rec['err.' + k] = err[k];
            })
            delete rec.err;
        }

        var leftover = Object.keys(rec);
        for (var i = 0; i < leftover.length; i++) {
            var key = leftover[i];
            var value = rec[key];
            var stringified = false;
            if (typeof (value) !== 'string') {
                value = JSON.stringify(value, null, 2);
                stringified = true;
            }
            if (value.indexOf('\n') !== -1 || value.length > 50) {
                details.push(indent(key + ': ' + value));
            } else if (!stringified && (value.indexOf(' ') != -1 ||
                value.length === 0))
            {
                extras.push(key + '=' + JSON.stringify(value));
            } else {
                extras.push(key + '=' + value);
            }
        }

        extras = stylize(
            (extras.length ? ' (' + extras.join(', ') + ')' : ''), 'XXX');
        details = stylize(
            (details.length ? details.join('\n    --\n') + '\n' : ''), 'XXX');
        if (!short)
            emit(format('%s %s: %s on %s%s:%s%s\n%s',
                time,
                level,
                nameStr,
                hostname || '<no-hostname>',
                src,
                onelineMsg,
                extras,
                details));
        else
            emit(format('%s %s %s:%s%s\n%s',
                time,
                level,
                nameStr,
                onelineMsg,
                extras,
                details));
        break;

    case OM_INSPECT:
        emit(util.inspect(rec, false, Infinity, true) + '\n');
        break;

    case OM_BUNYAN:
        emit(JSON.stringify(rec, null, 0) + '\n');
        break;

    case OM_JSON:
        emit(JSON.stringify(rec, null, opts.jsonIndent) + '\n');
        break;

    case OM_SIMPLE:
        /* JSSTYLED */
        // <http://logging.apache.org/log4j/1.2/apidocs/org/apache/log4j/SimpleLayout.html>
        if (!isValidRecord(rec)) {
            return emit(line + '\n');
        }
        emit(format('%s - %s\n',
            upperNameFromLevel[rec.level] || 'LVL' + rec.level,
            rec.msg));
        break;
    default:
        throw new Error('unknown output mode: '+opts.outputMode);
    }
}


var stdoutFlushed = true;
function emit(s) {
    try {
        stdoutFlushed = stdout.write(s);
    } catch (e) {
        // Handle any exceptions in stdout writing in `stdout.on('error', ...)`.
    }
}


/**
 * A hacked up version of 'process.exit' that will first drain stdout
 * before exiting. *WARNING: This doesn't stop event processing.* IOW,
 * callers have to be careful that code following this call isn't
 * accidentally executed.
 *
 * In node v0.6 "process.stdout and process.stderr are blocking when they
 * refer to regular files or TTY file descriptors." However, this hack might
 * still be necessary in a shell pipeline.
 */
function drainStdoutAndExit(code) {
    if (_DEBUG) warn('(drainStdoutAndExit(%d))', code);
    stdout.on('drain', function () {
        cleanupAndExit(code);
    });
    if (stdoutFlushed) {
        cleanupAndExit(code);
    }
}


/**
 * Process all input from stdin.
 *
 * @params opts {Object} Bunyan options object.
 * @param stylize {Function} Output stylize function to use.
 * @param callback {Function} `function ()`
 */
function processStdin(opts, stylize, callback) {
    readingStdin = true;
    var leftover = '';  // Left-over partial line from last chunk.
    var stdin = process.stdin;
    stdin.resume();
    stdin.setEncoding('utf8');
    stdin.on('data', function (chunk) {
        var lines = chunk.split(/\r\n|\n/);
        var length = lines.length;
        if (length === 1) {
            leftover += lines[0];
            return;
        }

        if (length > 1) {
            handleLogLine(null, leftover + lines[0], opts, stylize);
        }
        leftover = lines.pop();
        length -= 1;
        for (var i = 1; i < length; i++) {
            handleLogLine(null, lines[i], opts, stylize);
        }
    });
    stdin.on('end', function () {
        if (leftover) {
            handleLogLine(null, leftover, opts, stylize);
            leftover = '';
        }
        callback();
    });
}


/**
 * Process bunyan:log-* probes from the given pid.
 *
 * @params opts {Object} Bunyan options object.
 * @param stylize {Function} Output stylize function to use.
 * @param callback {Function} `function (code)`
 */
function processPids(opts, stylize, callback) {
    var leftover = '';  // Left-over partial line from last chunk.

    /**
     * Get the PIDs to dtrace.
     *
     * @param cb {Function} `function (errCode, pids)`
     */
    function getPids(cb) {
        if (opts.pidsType === 'num') {
            return cb(null, opts.pids);
        }
        if (process.platform === 'sunos') {
            execFile('/bin/pgrep', ['-lf', opts.pids],
                function (pidsErr, stdout, stderr) {
                    if (pidsErr) {
                        warn('bunyan: error getting PIDs for "%s": %s\n%s\n%s',
                            opts.pids, pidsErr.message, stdout, stderr);
                        return cb(1);
                    }
                    var pids = stdout.trim().split('\n')
                        .map(function (line) {
                            return line.trim().split(/\s+/)[0]
                        })
                        .filter(function (pid) {
                            return Number(pid) !== process.pid
                        });
                    if (pids.length === 0) {
                        warn('bunyan: error: no matching PIDs found for "%s"',
                            opts.pids);
                        return cb(2);
                    }
                    cb(null, pids);
                }
            );
        } else {
            var regex = opts.pids;
            if (regex && /[a-zA-Z0-9_]/.test(regex[0])) {
                // 'foo' -> '[f]oo' trick to exclude the 'grep' PID from its
                // own search.
                regex = '[' + regex[0] + ']' + regex.slice(1);
            }
            exec(format('ps -A -o pid,command | grep \'%s\'', regex),
                function (pidsErr, stdout, stderr) {
                    if (pidsErr) {
                        warn('bunyan: error getting PIDs for "%s": %s\n%s\n%s',
                            opts.pids, pidsErr.message, stdout, stderr);
                        return cb(1);
                    }
                    var pids = stdout.trim().split('\n')
                        .map(function (line) {
                            return line.trim().split(/\s+/)[0];
                        })
                        .filter(function (pid) {
                            return Number(pid) !== process.pid;
                        });
                    if (pids.length === 0) {
                        warn('bunyan: error: no matching PIDs found for "%s"',
                            opts.pids);
                        return cb(2);
                    }
                    cb(null, pids);
                }
            );
        }
    }

    getPids(function (errCode, pids) {
        if (errCode) {
            return callback(errCode);
        }

        var probes = pids.map(function (pid) {
            if (!opts.level)
                return format('bunyan%s:::log-*', pid);

            var rval = [], l;

            for (l in levelFromName) {
                if (levelFromName[l] >= opts.level)
                    rval.push(format('bunyan%s:::log-%s', pid, l));
            }

            if (rval.length != 0)
                return rval.join(',');

            warn('bunyan: error: level (%d) exceeds maximum logging level',
                opts.level);
            return drainStdoutAndExit(1);
        }).join(',');
        var argv = ['dtrace', '-Z', '-x', 'strsize=4k',
            '-x', 'switchrate=10hz', '-qn',
            format('%s{printf("%s", copyinstr(arg0))}', probes)];
        //console.log('dtrace argv: %s', argv);
        var dtrace = spawn(argv[0], argv.slice(1),
            // Share the stderr handle to have error output come
            // straight through. Only supported in v0.8+.
            {stdio: ['pipe', 'pipe', process.stderr]});
        dtrace.on('error', function (e) {
            if (e.syscall === 'spawn' && e.errno === 'ENOENT') {
                console.error('bunyan: error: could not spawn "dtrace" ' +
                    '("bunyan -p" is only supported on platforms with dtrace)');
            } else {
                console.error('bunyan: error: unexpected dtrace error: %s', e);
            }
            callback(1);
        })
        child = dtrace; // intentionally global

        function finish(code) {
            if (leftover) {
                handleLogLine(null, leftover, opts, stylize);
                leftover = '';
            }
            callback(code);
        }

        dtrace.stdout.setEncoding('utf8');
        dtrace.stdout.on('data', function (chunk) {
            var lines = chunk.split(/\r\n|\n/);
            var length = lines.length;
            if (length === 1) {
                leftover += lines[0];
                return;
            }
            if (length > 1) {
                handleLogLine(null, leftover + lines[0], opts, stylize);
            }
            leftover = lines.pop();
            length -= 1;
            for (var i = 1; i < length; i++) {
                handleLogLine(null, lines[i], opts, stylize);
            }
        });

        if (nodeSpawnSupportsStdio) {
            dtrace.on('exit', finish);
        } else {
            // Fallback (for < v0.8) to pipe the dtrace process' stderr to
            // this stderr. Wait for all of (1) process 'exit', (2) stderr
            // 'end', and (2) stdout 'end' before returning to ensure all
            // stderr is flushed (issue #54).
            var returnCode = null;
            var eventsRemaining = 3;
            function countdownToFinish(code) {
                returnCode = code;
                eventsRemaining--;
                if (eventsRemaining == 0) {
                    finish(returnCode);
                }
            }
            dtrace.stderr.pipe(process.stderr);
            dtrace.stderr.on('end', countdownToFinish);
            dtrace.stderr.on('end', countdownToFinish);
            dtrace.on('exit', countdownToFinish);
        }
    });
}


/**
 * Process all input from the given log file.
 *
 * @param file {String} Log file path to process.
 * @params opts {Object} Bunyan options object.
 * @param stylize {Function} Output stylize function to use.
 * @param callback {Function} `function ()`
 */
function processFile(file, opts, stylize, callback) {
    var stream = fs.createReadStream(file);
    if (/\.gz$/.test(file)) {
        stream = stream.pipe(require('zlib').createGunzip());
    }
    // Manually decode streams - lazy load here as per node/lib/fs.js
    var decoder = new (require('string_decoder').StringDecoder)('utf8');

    streams[file].stream = stream;

    stream.on('error', function (err) {
        streams[file].done = true;
        callback(err);
    });

    var leftover = '';  // Left-over partial line from last chunk.
    stream.on('data', function (data) {
        var chunk = decoder.write(data);
        if (!chunk.length) {
            return;
        }
        var lines = chunk.split(/\r\n|\n/);
        var length = lines.length;
        if (length === 1) {
            leftover += lines[0];
            return;
        }

        if (length > 1) {
            handleLogLine(file, leftover + lines[0], opts, stylize);
        }
        leftover = lines.pop();
        length -= 1;
        for (var i = 1; i < length; i++) {
            handleLogLine(file, lines[i], opts, stylize);
        }
    });

    stream.on('end', function () {
        streams[file].done = true;
        if (leftover) {
            handleLogLine(file, leftover, opts, stylize);
            leftover = '';
        } else {
            emitNextRecord(opts, stylize);
        }
        callback();
    });
}


/**
 * From node async module.
 */
/* BEGIN JSSTYLED */
function asyncForEach(arr, iterator, callback) {
    callback = callback || function () {};
    if (!arr.length) {
        return callback();
    }
    var completed = 0;
    arr.forEach(function (x) {
        iterator(x, function (err) {
            if (err) {
                callback(err);
                callback = function () {};
            }
            else {
                completed += 1;
                if (completed === arr.length) {
                    callback();
                }
            }
        });
    });
};
/* END JSSTYLED */



/**
 * Cleanup and exit properly.
 *
 * Warning: this doesn't stop processing, i.e. process exit might be delayed.
 * It is up to the caller to ensure that no subsequent bunyan processing
 * is done after calling this.
 *
 * @param code {Number} exit code.
 * @param signal {String} Optional signal name, if this was exitting because
 *    of a signal.
 */
var cleanedUp = false;
function cleanupAndExit(code, signal) {
    // Guard one call.
    if (cleanedUp) {
        return;
    }
    cleanedUp = true;
    if (_DEBUG) warn('(bunyan: cleanupAndExit)');

    // Clear possibly interrupted ANSI code (issue #59).
    if (usingAnsiCodes) {
        stdout.write('\033[0m');
    }

    // Kill possible dtrace child.
    if (child) {
        child.kill(signal);
    }

    if (pager) {
        // Let pager know that output is done, then wait for pager to exit.
        stdout.end();
        pager.on('exit', function (pagerCode) {
            if (_DEBUG)
                warn('(bunyan: pager exit -> process.exit(%s))',
                    pagerCode || code);
            process.exit(pagerCode || code);
        });
    } else {
        if (_DEBUG) warn('(bunyan: process.exit(%s))', code);
        process.exit(code);
    }
}



//---- mainline

process.on('SIGINT', function () {
    /**
     * Ignore SIGINT (Ctrl+C) if processing stdin -- we should process
     * remaining output from preceding process in the pipeline and
     * except *it* to close.
     */
    if (!readingStdin) {
        cleanupAndExit(1, 'SIGINT');
    }
});
process.on('SIGQUIT', function () { cleanupAndExit(1, 'SIGQUIT'); });
process.on('SIGTERM', function () { cleanupAndExit(1, 'SIGTERM'); });
process.on('SIGHUP', function () { cleanupAndExit(1, 'SIGHUP'); });

process.on('uncaughtException', function (err) {
    function _indent(s) {
        var lines = s.split(/\r?\n/);
        for (var i = 0; i < lines.length; i++) {
            lines[i] = '*     ' + lines[i];
        }
        return lines.join('\n');
    }

    var title = encodeURIComponent(format(
        'Bunyan %s crashed: %s', getVersion(), String(err)));
    var e = console.error;
    e('```');
    e('* The Bunyan CLI crashed!');
    e('*');
    if (err.name === 'ReferenceError' && gUsingConditionOpts) {
        /* BEGIN JSSTYLED */
        e('* This crash was due to a "ReferenceError", which is often the result of given');
        e('* `-c CONDITION` code that doesn\'t guard against undefined values. If that is');
        /* END JSSTYLED */
        e('* not the problem:');
        e('*');
    }
    e('* Please report this issue and include the details below:');
    e('*');
    e('*    https://github.com/trentm/node-bunyan/issues/new?title=%s', title);
    e('*');
    e('* * *');
    e('* platform:', process.platform);
    e('* node version:', process.version);
    e('* bunyan version:', getVersion());
    e('* argv: %j', process.argv);
    e('* log line: %j', currLine);
    e('* stack:');
    e(_indent(err.stack));
    e('```');
    process.exit(1);
});


function main(argv) {
    try {
        var opts = parseArgv(argv);
    } catch (e) {
        warn('bunyan: error: %s', e.message);
        return drainStdoutAndExit(1);
    }
    if (opts.help) {
        printHelp();
        return;
    }
    if (opts.version) {
        console.log('bunyan ' + getVersion());
        return;
    }
    if (opts.pid && opts.args.length > 0) {
        warn('bunyan: error: can\'t use both "-p PID" (%s) and file (%s) args',
            opts.pid, opts.args.join(' '));
        return drainStdoutAndExit(1);
    }
    if (opts.color === null) {
        if (process.env.BUNYAN_NO_COLOR &&
                process.env.BUNYAN_NO_COLOR.length > 0) {
            opts.color = false;
        } else {
            opts.color = process.stdout.isTTY;
        }
    }
    usingAnsiCodes = opts.color; // intentionally global
    var stylize = (opts.color ? stylizeWithColor : stylizeWithoutColor);

    // Pager.
    var paginate = (
        process.stdout.isTTY &&
        process.stdin.isTTY &&
        !opts.pids && // Don't page if following process output.
        opts.args.length > 0 && // Don't page if no file args to process.
        process.platform !== 'win32' &&
        (nodeVer[0] > 0 || nodeVer[1] >= 8) &&
        (opts.paginate === true ||
            (opts.paginate !== false &&
                (!process.env.BUNYAN_NO_PAGER ||
                    process.env.BUNYAN_NO_PAGER.length === 0))));
    if (paginate) {
        var pagerCmd = process.env.PAGER || 'less';
        /* JSSTYLED */
        assert.ok(pagerCmd.indexOf('"') === -1 && pagerCmd.indexOf("'") === -1,
            'cannot parse PAGER quotes yet');
        var argv = pagerCmd.split(/\s+/g);
        var env = objCopy(process.env);
        if (env.LESS === undefined) {
            // git's default is LESS=FRSX. I don't like the 'S' here because
            // lines are *typically* wide with bunyan output and scrolling
            // horizontally is a royal pain. Note a bug in Mac's `less -F`,
            // such that SIGWINCH can kill it. If that rears too much then
            // I'll remove 'F' from here.
            env.LESS = 'FRX';
        }
        if (_DEBUG) warn('(pager: argv=%j, env.LESS=%j)', argv, env.LESS);
        // `pager` and `stdout` intentionally global.
        pager = spawn(argv[0], argv.slice(1),
            // Share the stderr handle to have error output come
            // straight through. Only supported in v0.8+.
            {env: env, stdio: ['pipe', 1, 2]});
        stdout = pager.stdin;

        // Early termination of the pager: just stop.
        pager.on('exit', function (pagerCode) {
            if (_DEBUG) warn('(bunyan: pager exit)');
            pager = null;
            stdout.end()
            stdout = process.stdout;
            cleanupAndExit(pagerCode);
        });
    }

    // Stdout error handling. (Couldn't setup until `stdout` was determined.)
    stdout.on('error', function (err) {
        if (_DEBUG) warn('(stdout error event: %s)', err);
        if (err.code === 'EPIPE') {
            drainStdoutAndExit(0);
        } else if (err.toString() === 'Error: This socket is closed.') {
            // Could get this if the pager closes its stdin, but hasn't
            // exited yet.
            drainStdoutAndExit(1);
        } else {
            warn(err);
            drainStdoutAndExit(1);
        }
    });

    var retval = 0;
    if (opts.pids) {
        processPids(opts, stylize, function (code) {
            cleanupAndExit(code);
        });
    } else if (opts.args.length > 0) {
        var files = opts.args;
        files.forEach(function (file) {
            streams[file] = { stream: null, records: [], done: false }
        });
        asyncForEach(files,
            function (file, next) {
                processFile(file, opts, stylize, function (err) {
                    if (err) {
                        warn('bunyan: %s', err.message);
                        retval += 1;
                    }
                    next();
                });
            },
            function (err) {
                if (err) {
                    warn('bunyan: unexpected error: %s', err.stack || err);
                    return drainStdoutAndExit(1);
                }
                cleanupAndExit(retval);
            }
        );
    } else {
        processStdin(opts, stylize, function () {
            cleanupAndExit(retval);
        });
    }
}

if (require.main === module) {
    // HACK guard for <https://github.com/trentm/json/issues/24>.
    // We override the `process.stdout.end` guard that core node.js puts in
    // place. The real fix is that `.end()` shouldn't be called on stdout
    // in node core. Node v0.6.9 fixes that. Only guard for v0.6.0..v0.6.8.
    if ([0, 6, 0] <= nodeVer && nodeVer <= [0, 6, 8]) {
        var stdout = process.stdout;
        stdout.end = stdout.destroy = stdout.destroySoon = function () {
            /* pass */
        };
    }

    main(process.argv);
}
