UNIXUtilities.swift

//
//  NSTaskWrapper.swift
//
//  Created by Joel Rennich on 3/29/16.
//  Copyright © 2018 Orchard & Grove Inc. All rights reserved.
//

// v. 1.4.1

import Foundation
import SystemConfiguration
import IOKit


/// A simple wrapper around NSTask
///
/// - Parameters:
///   - command: The `String` of the command to run. A full path to the binary is not required. Arguments can be in the main string.
///   - arguments: An optional `Array` of `String` values that represent the arguments given to the command. Defaults to 'nil'.
///   - waitForTermination: An optional `Bool` Should the the output be delayed until the task exits. Deafults to 'true'.
/// - Returns: The combined result of standard output and standard error from the command.
public func cliTask(_ command: String, arguments: [String]? = nil, waitForTermination: Bool = true) -> String {

    var commandLaunchPath: String
    var commandPieces: [String]
    
    if arguments == nil {
        // turn the command into an array and get the first element as the launch path
        commandPieces = command.components(separatedBy: " ")
        // loop through the components and see if any end in \
        if command.contains("\\") {

            // we need to rebuild the string with the right components
            var x = 0
            for line in commandPieces {
                if line.last == "\\" {
                    commandPieces[x] = commandPieces[x].replacingOccurrences(of: "\\", with: " ") + commandPieces.remove(at: x+1)
                    x -= 1
                }
                x += 1
            }
        }
        commandLaunchPath = commandPieces.remove(at: 0)
    } else {
        commandLaunchPath = command
        commandPieces = arguments!
        //TCSLogWithMark(commandLaunchPath + " " + arguments!.joinWithSeparator(" "))
    }

    // make sure the launch path is the full path -- think we're going down a rabbit hole here

    if !commandLaunchPath.contains("/") {
        let realPath = which(commandLaunchPath)
        commandLaunchPath = realPath
    }

    // set up the NSTask instance and an NSPipe for the result

    let myTask = Process()
    let outputPipe = Pipe()
    let myInputPipe = Pipe()
    let myErrorPipe = Pipe()
    var outputString = ""
    // Setup and Launch!

    myTask.launchPath = commandLaunchPath
    myTask.arguments = commandPieces
    myTask.standardOutput = outputPipe
    myTask.standardInput = myInputPipe
    myTask.standardError = myErrorPipe

    myTask.launch()
    
    while (true) {
        let data = outputPipe.fileHandleForReading.readData(ofLength: 1024)

        if data.count <= 0 {
            break
        }

        if let str = String(data: data, encoding: .utf8) {
            outputString += str
        }
    }

    if waitForTermination == true {
        myTask.waitUntilExit()
    }

    let error = myErrorPipe.fileHandleForReading.readDataToEndOfFile()
    let outputError = NSString(data: error, encoding: String.Encoding.utf8.rawValue)! as String
    
    return outputString + outputError
}

public func cliTask(_ command: String,
                    arguments: [String]? = nil,
                    completion: @escaping ((String) -> Void)) {

    var commandLaunchPath: String
    var commandPieces: [String]

    if arguments == nil {
        // turn the command into an array and get the first element as the launch path
        commandPieces = command.components(separatedBy: " ")
        // loop through the components and see if any end in \
        if command.contains("\\") {

            // we need to rebuild the string with the right components
            var x = 0
            for line in commandPieces {
                if line.last == "\\" {
                    commandPieces[x] = commandPieces[x].replacingOccurrences(of: "\\", with: " ") + commandPieces.remove(at: x+1)
                    x -= 1
                }
                x += 1
            }
        }
        commandLaunchPath = commandPieces.remove(at: 0)
    } else {
        commandLaunchPath = command
        commandPieces = arguments!
        //TCSLogWithMark(commandLaunchPath + " " + arguments!.joinWithSeparator(" "))
    }

    // make sure the launch path is the full path -- think we're going down a rabbit hole here

    if !commandLaunchPath.contains("/") {
        let realPath = which(commandLaunchPath)
        commandLaunchPath = realPath
    }

    // set up the NSTask instance and an NSPipe for the result

    let myTask = Process()

    let myPipe = Pipe()
    let myInputPipe = Pipe()
    let myErrorPipe = Pipe()

    // Setup and Launch!

    myTask.launchPath = commandLaunchPath
    myTask.arguments = commandPieces
    myTask.standardOutput = myPipe
    myTask.standardInput = myInputPipe
    myTask.standardError = myErrorPipe

    myTask.terminationHandler = { process in
        let data = myPipe.fileHandleForReading.readDataToEndOfFile()
        let error = myErrorPipe.fileHandleForReading.readDataToEndOfFile()
        let outputError = NSString(data: error, encoding: String.Encoding.utf8.rawValue)! as String
        let output = NSString(data: data, encoding: String.Encoding.utf8.rawValue)! as String
        completion(output + outputError)
    }

    myTask.launch()
}

/// A simple wrapper around NSTask that also doesn't wait for the `Task` termination signal.
///
/// - Parameter command: The `String` of the command to run. A full path to the binary is not required.
/// - Returns: The combined result of standard output and standard error from the command.
@available(*, deprecated)
public func cliTaskNoTerm(_ command: String) -> String {

    // This is here because klist -v won't actually trigger the NSTask termination

    // turn the command into an array and get the first element as the launch path

    var commandPieces = command.components(separatedBy: " ")

    // loop through the components and see if any end in \

    if command.contains("\\") {

        // we need to rebuild the string with the right components
        var x = 0

        for line in commandPieces {
            if line.last == "\\" {
                commandPieces[x] = commandPieces[x].replacingOccurrences(of: "\\", with: " ") + commandPieces.remove(at: x+1)
                x -= 1
            }
            x += 1
        }
    }

    var commandLaunchPath = commandPieces.remove(at: 0)

    // make sure the launch path is the full path -- think we're going down a rabbit hole here

    if !commandLaunchPath.contains("/") {
        let realPath = which(commandLaunchPath)
        commandLaunchPath = realPath
    }

    // set up the NSTask instance and an NSPipe for the result

    let myTask = Process()
    let myPipe = Pipe()
    let myInputPipe = Pipe()
    let myErrorPipe = Pipe()

    // Setup and Launch!

    myTask.launchPath = commandLaunchPath
    myTask.arguments = commandPieces
    myTask.standardOutput = myPipe
    myTask.standardInput = myInputPipe
    myTask.standardError = myErrorPipe

    myTask.launch()

    let data = myPipe.fileHandleForReading.readDataToEndOfFile()
    let output = NSString(data: data, encoding: String.Encoding.utf8.rawValue)! as String

    return output
}

/// Find the short name of the current console user.
///
/// - Returns: The current, logged in, user's short name as a `String`.
public func getConsoleUser() -> String {
    var uid: uid_t = 0
    var gid: gid_t = 0
    var userName = ""

    // use SCDynamicStore to find out who the console user is

    let theResult = SCDynamicStoreCopyConsoleUser( nil, &uid, &gid)
    userName = theResult! as String
    return userName
}


/// Finds the serial number of the Mac.
///
/// - Returns: The serial number of the Mac as a `String`.
public func getSerial() -> String {
    let platformExpert: io_service_t = IOServiceGetMatchingService(kIOMasterPortDefault, IOServiceMatching("IOPlatformExpertDevice"))
    let platformSerialNumberKey = kIOPlatformSerialNumberKey
    let serialNumberAsCFString = IORegistryEntryCreateCFProperty(platformExpert, platformSerialNumberKey as CFString, kCFAllocatorDefault, 0)
    let serialNumber = serialNumberAsCFString?.takeUnretainedValue() as! String
    return serialNumber

}

/// Finds the MAC address of the primary ethernet connection.
///
/// - Returns: First MAC address of Mac as a `String`.
public func getMAC() -> String {

    let myMACOutput = cliTask("/sbin/ifconfig -a").components(separatedBy: "\n")
    var myMac = ""

    for line in myMACOutput {
        if line.contains("ether") {
            myMac = line.replacingOccurrences(of: "ether", with: "").trimmingCharacters(in: CharacterSet.whitespaces)
            break
        }
    }
    return myMac
}

// private function to get the path to the binary if the full path isn't given

/// Private function to get the path to a binary if the full path isn't given
///
/// - Parameter command: A `String` of the UNIX command to find the qualified path to.
/// - Returns: A fully qualified path to any UNIX binary on the system from the which database.
private func which(_ command: String) -> String {
    let task = Process()
    task.launchPath = "/usr/bin/which"
    task.arguments = [command]

    let whichPipe = Pipe()
    task.standardOutput = whichPipe
    task.launch()

    let data = whichPipe.fileHandleForReading.readDataToEndOfFile()
    let output = NSString(data: data, encoding: String.Encoding.utf8.rawValue)! as String
    
    if output == "" {
        NSLog("Binary doesn't exist")
    }
    return output.components(separatedBy: "\n").first!
}