/**
 * Returns true if the value is in the array.
 *
 * @param {Array} arr
 * @param {*} val
 * @returns {boolean}
 */

function checkValIn(arr, val) { 
  return arr.indexOf(val) > -1; 
}

var arr_cvi = [1, 2, 3, 4];
Logger.log(checkValIn(arr_cvi, 5)); // false

/**
 * Returns an array with no duplicate values.
 *
 * @param {Array} arr 
 * @returns {Array}
 */

function rmDuplicatesFrom(arr) {
  var check  = {};
  var result = [];
  var j = 0;
  for(var i = 0; i < arr.length; i++) {
    var item = arr[i];
    if(check[item] !== 1) {
      check[item] = 1;
      result[j++] = item;
    }
  }
  return result;
}

var arr_rdf = [1, 2, 3, 1, 2, 3, 4,];
Logger.log(rmDuplicatesFrom(arr_rdf)); // [1, 2, 3, 4]

/**
 * Returns an array with no empty elements.
 *
 * @param {*} x
 * @returns {Array}
 */

function rmEmptyEl(x) {
  return (x !== (undefined || ''));
}

var arr_rev = ["a",,"b",,,"c"];
Logger.log(arr_rev.filter(rmEmptyEl)); // ["a", "b", "c"]

/**
 * Returns an array of objects. Objects have two properties, count and value.
 *
 * @param {Array} arr
 * @property {value} a value found in the array
 * @property {count} count of the value in the array
 * @returns {Object[]}
 */

function countOfValIn(arr) {
  var result = [];
  var copy = arr.slice(0);
  for (var i = 0; i < arr.length; i++) {
    var myCount = 0;  
    for (var w = 0; w < copy.length; w++) {
      if (arr[i] == copy[w]) {
        myCount++;
        delete copy[w];
      }
    }
    if (myCount > 0) {
      var obj   = {};
      obj.value = arr[i];
      obj.count = myCount;
      result.push(obj);
    }
  }
  return result;
}

var arr_covi  = ["a", "b", "c", "a", "b", "c", "a"];
Logger.log(countOfValIn(arr_covi)); // [{count=3.0, value=a}, {count=2.0, value=b}, {count=2.0, value=c}]

/**
 * Returns an array of the elements in both arrays.
 *
 * @param {Array} arrA
 * @param {Array} arrB
 * @returns {Array}
 */

function intersectOf(arrA, arrB) {
  var a = 0;
  var b = 0;
  var result = [];
  while( a < arrA.length && b < arrB.length ) {
    if (arrA[a] < arrB[b] ) { a++; }
    else if (arrA[a] > arrB[b] ) { b++; }
    else {
      result.push(arrA[a]);
      a++;
      b++;
    }
  }
  return result;
}

var arrA_io = [1, 2, 3];
var arrB_io = [3, 4, 5];
Logger.log(intersectOf(arrA_io, arrB_io)); // [3]

/**
 * Returns true if both arrays have the same elements in the same order.
 *
 * @param {Array} arrA
 * @param {Array} arrB
 * @returns {boolean}
 */

function compareArr(arrA, arrB) {
  if(arrA.length !== arrB.length) return false;
  for(var i = arrA.length; i--;) {
    if(arrA[i] !== arrB[i]) return false;
  }
  return true;
}

var arrA_ca = [1, 2, 3, 4, 5];
var arrB_ca = [1, 2, 3, 4, 5];
var arrC_ca = ["a", "b", "c", "d", "e"];
Logger.log(compareArr(arrA_ca, arrB_ca)); // true
Logger.log(compareArr(arrA_ca, arrC_ca)); // false

/**
 * Returns a string of array values. 
 * Elements are separated by a delimiter and a space.
 *
 * @param {Array} arr
 * @param {string} delim
 * @returns {string}
 */

function delimStrFromArr(arr, delim) {
  var _arr = rmDuplicatesFrom(arr).sort();
  var result  = "";
  for (var i = 0; i < _arr.length; i++) {
    result += _arr[i] + delim + " ";
  }
  result = result.slice(0, -2);
  return result;
}

var arr_da = ["[email protected]", "[email protected]", "[email protected]"];
Logger.log(delimStrFromArr(arr_da, ",")); // "[email protected], [email protected], [email protected]"

/**
 * Returns a string of array values.
 * Elements are separated by a delimiter and a space, each followed by a modification.
 *
 * @param {Array} arr
 * @param {string} delim
 * @param {string} mod Modification to append to each item in the array.
 * @returns {string}
 */

function delimStrFromArrMod(arr, delim, mod) {
  var _arr = rmDuplicatesFrom(arr).sort();
  var result  = "";
  for (var i = 0; i < _arr.length; i++) {
    result += _arr[i] + mod + delim + " "; 
  }
  result = result.slice(0, -2);
  return result;
}

var arr_clfd = ["x", "z", "y"];
Logger.log(delimStrFromArrMod(arr_clfd, ",", "@example.com")); // "[email protected], [email protected], [email protected]"

/**
 * Returns an array containing all values in a two-dimensional array.
 *
 * @param {Array[]} twoDArr
 * @returns {Array} 
 */

function flattenTwoDArr(twoDArr) {
  var result = twoDArr.reduce(function(a, b) {
    return a.concat(b);
  });
  return result;
}

var sheet_fma = SpreadsheetApp.getActiveSpreadsheet().getSheetByName("Sheet1");
var val_fma   = sheet_fma.getRange("G2:H5").getValues();
Logger.log(flattenTwoDArr(val_fma).sort()); // [1, 2, 3, 4, 5, 6, 7, 8]

var ex_arrObj = [
{a: 1000, b: 1, c: 5}, 
{a: 10000, b: 2, c: 5000}, 
{a: 10, b: 2, c: 500},
{a: 1, b: 1, c: 50}
]

/**
 * Returns an array of objects sorted by a single property value.
 *
 * @param {string} prop
 * @returns {Object[]}
 */

function dynSort(prop) {
  var sortOrder = 1;
  if(prop[0] === "-") {
    sortOrder = -1;
    prop = prop.substr(1);
  }
  return function (a,b) {
    var result = (a[prop] < b[prop]) ? -1 : (a[prop] > b[prop]) ? 1 : 0;
    return result * sortOrder;
  };
}

Logger.log(ex_arrObj.sort(dynSort("a"))); 
// [{a=1.0, b=1.0, c=50.0}, {a=10.0, b=2.0, c=500.0}, {a=1000.0, b=1.0, c=5.0}, {a=10000.0, b=2.0, c=5000.0}]

/**
 * Returns an array of objects sorted by multiple property values.
 * @param {...string}
 * @returns {Object[]}
 */

function dynSortM() {
  var props = arguments;
  return function (obj1, obj2) {
    var i = 0, result = 0, numberOfProperties = props.length;
    while(result === 0 && i < numberOfProperties) {
      result = dynSort(props[i])(obj1, obj2);
      i++;
    }
    return result;
  };
}

Logger.log(ex_/rrObj.sort(dynSortM("b", "c"))); 
// [{a=1000.0, b=1.0, c=5.0}, {a=1.0, b=1.0, c=50.0}, {a=10.0, b=2.0, c=500.0}, {a=10000.0, b=2.0, c=5000.0}]

/**
 * Returns the first object in an array of objects with the key value pair.
 *
 * @param {Object[]} arrObj
 * @param {string} pQuery
 * @param {string} val
 * @returns {Object}
 */

function findObjIn(arrObj, pQuery, val) {
  for (var i = 0; i < arrObj.length; i++) {
    var obj = arrObj[i];
    for (var prop in obj) {
      if (obj.hasOwnProperty(pQuery) && prop == pQuery && obj[prop] == val) {
        return obj;
      }
    }
  }
}

Logger.log(findObjIn(ex_arrObj,"a",1000)); // {a=1000.0, b=1.0, c=5.0}

/**
 * Returns a value from the first matching object in the array.
 *
 * @param {Object[]} arrObj
 * @param {string} pQuery
 * @param {string} val
 * @param {string} pReturn
 * @returns {*}
 */

function findObjValIn(arrObj, pQuery, val, pReturn) {
  for (var i = 0; i < arrObj.length; i++) {
    var obj = arrObj[i];
    for (var prop in obj) {
      if (obj.hasOwnProperty(pQuery) && prop == pQuery && obj[prop] == val) {
        return obj[pReturn];
      }
    }
  }
}

Logger.log(findObjValIn(ex_arrObj, "c", 500, "a")); // 10

/**
 * Returns the object with the oldest Timestamp value.
 *
 * @param {Object[]} arrObj
 * @returns {Object}
 */

function earliestTS(arrObj){
  if (arrObj.length >= 2) {
    var sorted = arrObj.sort(function(a,b){
      return new Date(a.Timestamp) - new Date(b.Timestamp);
    });
    return sorted[0];
  } else {
    return arrObj[0];
  }
}

var sheet_fe  = SpreadsheetApp.getActiveSpreadsheet().getSheetByName("Sheet1");
var arrObj_fe = arrObjFromRange(sheet_fe, "J1:K4");
Logger.log(earliestTS(arrObj_fe)); // {Timestamp=Sun Feb 19 19:43:40 GMT-06:00 2017, Multiple Choice=A}

/**
 * Returns the object with the latest Timestamp value.
 *
 * @param {Object[]} arrObj
 * @returns {Object}
 */

function latestTS(arrObj) {
  if (arrObj.length >= 2) {
    var sorted = arrObj.sort(function(a,b){
      return new Date(b.Timestamp) - new Date(a.Timestamp);
    });
    return sorted[0];
  } else {
    return arrObj[0];
  }
} 

var sheet_le  = SpreadsheetApp.getActiveSpreadsheet().getSheetByName("Sheet1");
var arrObj_le = arrObjFromRange(sheet_le, "J1:K4");
Logger.log(latestTS(arrObj_le)); // {Timestamp=Wed Feb 22 19:45:07 GMT-06:00 2017, Multiple Choice=C}

/**
 * Returns an array of objects containing matching objects.
 *
 * @param {Object} arrObj
 * @param {string} pQuery
 * @param {string[]} arrVal
 * @returns {Object[]}
 */

function filterObjIn(arrObj, pQuery, arrVal) {
  var result = [];
  for (var i = 0; i < arrVal.length; i++) {
    var val = arrVal[i]; 
    for (var j = 0; j < arrObj.length; j++) {
      if (arrObj[j][pQuery] == val) result.push(arrObj[j]);
    }
  } 
  return result;
}

Logger.log(filterObjIn(ex_arrObj, "a", [10])); // [{a=10.0, b=2.0, c=500.0}]
Logger.log(filterObjIn(ex_arrObj, "c", [5, 500])); // [{a=1000.0, b=1.0, c=5.0}, {a=10.0, b=2.0, c=500.0}]

/**
 * Returns an array of objects, with an additional property value added to each matching object.
 *
 * @param {Object[]} arrObj
 * @param {string[]} arrProp
 * @param {string} newProp 
 * @returns {Object[]}
 */

function unifyPropForArrObj(arrObj, arrProp, newProp){
  for (var i = 0; i < arrObj.length; i++){
    var obj = arrObj[i];
    for (var h = 0; h < arrProp.length; h++) {
      for (var prop in obj) {
        if (obj.hasOwnProperty(prop) && prop == arrProp[h] && obj[prop] !== ""){
              obj[newProp] = obj[prop];
        }
      }
    }
  }
  return arrObj;
}

var arrObj_upfao  = [
  {x: 123},
  {y: 234},
  {z: 345},
];

Logger.log(unifyPropForArrObj(arrObj_upfao, ["x","y","z"], "new"));
// [{new=123.0, x=123.0}, {new=234.0, y=234.0}, {new=345.0, z=345.0}]

/**
 * Returns an array of matching properties. 
 *
 * @requires intersectOf() 
 * @param {Object} obj
 * @param {string[]} props
 * @returns {Array}
 */

function filterValIn(obj, props) {
  var result = [];
  var keys   = intersectOf(Object.keys(obj), props);
  for (var i = 0; i < keys.length; i++) {
    var key = keys[i];
    for (var prop in obj) {
      if (obj.hasOwnProperty(key)) {
        result.push(obj[key]);
        break;
      }
    }
  }
  return result;
}

var obj_fvi = { 
 a: 1, 
 b: 2, 
 c: 3
};

var arr_fvi = ["a", "b", "d"];
Logger.log(filterValIn(obj_fvi, arr_fvi)); // [1, 2]

/**
 * Returns an object with the values of the argument objects.
 * If multiple objects have the same property value, the last value set is retained. 
 * @param {...Object}
 * @returns {Object}
 */

function mergeObjs() {
  var obj = arguments[0];
  for (i = 1; i < arguments.length; i++) {
    var src = arguments[i]; 
    for (var key in src) {
      if (src.hasOwnProperty(key)) obj[key] = src[key];
    }
  } 
  return obj;
} 

var objA_mo = {
 a: 1, 
 b: 2, 
 c: 3
}; 

var objB_mo = {
 c: 4,
 d: 5, 
 e: 6, 
 f: 7
}; 

Logger.log(mergeObjs(objA_mo, objB_mo)); // {a=1.0, b=2.0, c=4.0, d=5.0, e=6.0, f=7.0}

/**
 * Returns a string of today's date formatted "month-day-year".
 *
 * @returns {string}
 */

function fmatD() {
  var n = new Date();
  var d = [ n.getMonth() + 1, n.getDate(), n.getYear() ];
    return d.join("-");
}

Logger.log(fmatD()); // "4-24-2017"

/**
 * Returns a string of the current time formatted "hour:minute:second".
 *
 * @returns {string}
 */

function fmat24T(){
  var n  = new Date();
  var t = [ n.getHours(), n.getMinutes(), n.getSeconds() ];
    for ( var i = 1; i < 3; i++ ) {
      if ( t[i] < 10 ) {
        t[i] = "0" + t[i];
      }
      return t.join(":");
    }
}

Logger.log(fmat24T()); // "20:43:40"

/**
 * Returns a string of today's date and the current time formatted "month-day-year hour:minute:second AM/PM"
 *
 * @returns {string}
 */

function fmat12DT() {
  var n = new Date();
  var d = [ n.getMonth() + 1, n.getDate(), n.getYear() ];
    var t = [ n.getHours(), n.getMinutes(), n.getSeconds() ];
    var s = ( t[0] < 12 ) ? "AM" : "PM";
  t[0]  = ( t[0] <= 12 ) ? t[0] : t[0] - 12;
  for ( var i = 1; i < 3; i++ ) {
    if ( t[i] < 10 ) {
      t[i] = "0" + t[i];
    }
  }
  return d.join("/") + " " + t.join(":") + " " + s;
}

Logger.log(fmat12DT()); // "4-24-2017 8:43:40 PM"

/**
 * Returns a new date object from a string formatted year-month-date. 
 *
 * @param {string} str
 * @returns {Date}
 */

function dateObjectFromString(str) {
  var split  = str.split("-");
  var months = ["January", "February", "March", "April", "May", "June",
    "July", "August", "September", "October", "November", "December"
    ];
  return new Date (months[(split[1] - 1)] + " " + split[2] + ", " + split[0]);
}

Logger.log(dateObjectFromString("2017-04-24")); // Mon Apr 24 00:00:00 GMT-05:00 2017

/**
 * Returns a value associated with a date range.
 *
 * @param {Object[]} arrObj
 * @param {string=new Date()} optDate - Date to match.
 * @namespace
 * @property {string} start           - Starting date.
 * @property {string} end             - Ending date.
 * @property {*} value                - The value to return for a matching date.
 * @returns {*}
 */

function matchDateRange(arrObj, optDate) {
  var date = new Date();
  if (optDate !== undefined) {
    date = new Date(optDate);
  }
  for (i = 0; i < arrObj.length; i++) {
    var start = new Date(arrObj[i].start);
    var end   = new Date(arrObj[i].end);
    if (date >= start && date <= end ) {
      return arrObj[i].value;
    }
  }
}

var quarterDates = [
  {start: "08/01/2016", end: "10/28/2016", value: 1},
  {start: "11/02/2016", end: "01/09/2017", value: 2},
  {start: "01/15/2017", end: "03/19/2017", value: 3},
  {start: "03/21/2017", end: "06/15/2017", value: 4},
  {start: "06/16/2017", end: "07/30/2017", value: "summer vacation"}
];

Logger.log(matchDateRange(quarterDates)); // "summer vacation" (06/25/2017)
Logger.log(matchDateRange(quarterDates, "08/02/2016")); // 1 

// -- Create or Verify Folder Path

/**
 * Returns a folder at the end of a folder path.
 * The folder is created if it does not exist already.
 *
 * @param {string} path
 * @returns {Folder}
 */

function createVerifyPath(path) {
  var split = path.split('/');
  var fldr;
  for (i = 0; i < split.length; i++) {
    var fi = DriveApp.getRootFolder().getFoldersByName(split[i]);
    if (i === 0) {
      if(!(fi.hasNext())) {
        DriveApp.createFolder(split[i]);
        fi = DriveApp.getFoldersByName(split[i]);
      } 
      fldr = fi.next();
    } else if (i >= 1) {
      fi = fldr.getFoldersByName(split[i]);
      if(!(fi.hasNext())) {
        fldr.createFolder(split[i]);
        fi = DriveApp.getFoldersByName(split[i]);
      } 
      fldr = fi.next();
    }
  } 
  return fldr;
}

Logger.log(createVerifyPath("google-apps-script-cheat-sheet-demo/folders/A/B/C")); // C

/**
 * Returns the last folder in a folder path.
 *
 * @param path
 * @returns {Folder}
 */

function lastFolderIn(path) {
  var fi;
  var split = path.split('/');
  var fldr;
  for (i = 0; i < split.length; i++) {
    if (i === 0) {
      fi = DriveApp.getRootFolder().getFoldersByName(split[i]);
      if (fi.hasNext()) {
        fldr = fi.next();
      } 
    } else if (i >= 1) {
        fi = fldr.getFoldersByName(split[i]);
        if (fi.hasNext()) {
          fldr = fi.next();
        } 
    }
  } 
  return fldr;
}

// Logger.log(lastFolderIn("google-apps-script-cheat-sheet-demo/folders/A/B")); // B
// Logger.log(lastFolderIn("google-apps-script-cheat-sheet-demo/folders/A/B/C/D/E/F/G")); // C

/**
 * Returns an array of all folders in a folder.
 *
 * @param {Folder} fldr
 * @returns {Folder[]}
 */

function foldersIn(fldr) {
  var fi  = fldr.getFolders();
  var arr = [];
  while (fi.hasNext()) {
    var _fldr = fi.next();
    arr.push(_fldr);
  } 
  return arr;
}

Logger.log(foldersIn(lastFolderIn("google-apps-script-cheat-sheet-demo/folders/"))); // [A]

/**
 * Returns an array of all folders in the root of the user's Drive.
 *
 * @returns {Folder[]}
 */

function rootFolders() {
  var rf  = DriveApp.getRootFolder();
  var fi  = rf.getFolders();
  var arr = [];
  while (fi.hasNext()) {
    var fldr = fi.next();
    arr.push(fldr);
  } 
  return arr;
}

Logger.log(rootFolders());

/**
 * Returns an array of all folders in the user's Drive.
 *
 * @returns {Folder[]}
 */

function allFolders() {
  var fi  = DriveApp.getFolders();
  var arr = [];
  while (fi.hasNext()) {
    var fldr = fi.next();
    arr.push(fldr);
  } 
  return arr;
}

Logger.log(allFolders());

/**
 * Returns an array of folder names.
 *
 * @param {Folders[]}
 * @returns {string[]}
 */

function folderNames(fldrs) {
  var arr = [];
  for (var i = 0; i < fldrs.length; i++) {
    var name = fldrs[i].getName();
    arr.push(name);
  }
  return arr;
}

var arr_fn  = foldersIn(lastFolderIn("google-apps-script-cheat-sheet-demo/folders/A/B"));
Logger.log(folderNames(arr_fn)); // [C]

/**
 * Returns a folder.
 *
 * @requires foldersIn() 
 * @requires folderNames() 
 * @requires checkValIn()
 * @param {Folder} fldr
 * @param {string} name
 * @returns {Folder}
 */

function findFolderIn(fldr, name) {
  var fldrs = foldersIn(fldr);
  var names = folderNames(fldrs);
  if (checkValIn(names, name)) {
    var _fldr = fldr.getFoldersByName(name).next();
    return _fldr;
  }
}

var fldr_ffi = lastFolderIn("google-apps-script-cheat-sheet-demo/folders");
Logger.log(findFolderIn(fldr_ffi, "A")); // A

/**
 * Returns a folder at the root of the user's Drive.
 *
 * @requires rootFolders()
 * @requires folderNames()
 * @requires checkValIn()
 * @param {string} name
 * @returns {Folder}
 */

function findFolderAtRoot(name) {
  var rf    = DriveApp.getRootFolder();
  var fldrs = rootFolders();
  var names = folderNames(fldrs);
  if (checkValIn(names, name)) {
    var fldr = rf.getFoldersByName(name).next();
    return fldr;
  }
}

Logger.log(findFolderAtRoot("google-apps-script-cheat-sheet-demo")); // google-apps-script-cheat-sheet-demo

/**
 * Returns the first matching folder in Drive.
 *
 * @param {string} name
 * @returns {Folder}
 */

function findFolderInDrive(name) {
  var fi = DriveApp.getFoldersByName(name);
  while (fi.hasNext()){
    var fldr = fi.next();
    return fldr;
  }
}

Logger.log(findFolderInDrive("folders")); // folders

/**
 * Returns a folder. 
 * Creates folders within a folder if they don't already exist.
 *
 * @requires foldersIn()
 * @requires folderNames()
 * @requires checkValIn()
 * @param {Folder} fldr
 * @param {string[]} names
 * @returns {Folder}
 */

function createVerifyFoldersIn(fldr, names) {
  var fldrs  = foldersIn(fldr);
  var _names = folderNames(fldrs);
  for (i = 0; i < names.length; i++) {
    if (!(checkValIn(_names, names[i]))) {
      fldr.createFolder(names[i]);
    }
  }
  return fldr;
}

var fldr_cvfi = lastFolderIn("google-apps-script-cheat-sheet-demo/folders");
Logger.log(createVerifyFoldersIn(fldr_cvfi, ["X", "Y", "Z"])); // folders
Logger.log(foldersIn(fldr_cvfi)); // [A,X,Y,Z]

/**
 * Returns an array of files found at the top level of a folder.
 *
 * @param {Folder} fldr
 * @returns {File[]}
 */

function filesIn(fldr) {
  var fi  = fldr.getFiles();
  var arr = [];
  while (fi.hasNext()) {
    var file = fi.next();
    arr.push(file);
  } 
  return arr;
}

var fldr_fin = lastFolderIn("google-apps-script-cheat-sheet-demo/files");
Logger.log(filesIn(fldr_fin)); // [example-file]

/**
 * Returns an array of all files at the root of a user's Drive.
 *
 * @returns {File[]}
 */

function rootFiles() {
  var rf = DriveApp.getRootFolder();
  var fi = rf.getFiles();
  var arr = [];
  while (fi.hasNext()) {
    var file = fi.next();
    arr.push(file);
  } 
  return arr;
}

Logger.log(rootFiles());

/**
 * Returns an array of all files in the user's Drive.
 *
 * @returns {File[]}
 */

function allFiles() {
  var fi = DriveApp.getFiles();
  var arr  = [];
  while (fi.hasNext()) {
    var file = fi.next();
    arr.push(file);
  } 
  return arr;
}

Logger.log(allFiles());

/**
 *  Returns an array of file names.
 *
 * @param {File[]} files
 * @returns {string[]}
 */

function fileNames(files) {
  var arr = [];
  for (var i = 0; i < files.length; i++) {
    var name = files[i].getName();
    arr.push(name);
  }
  return arr;
}

var fldr_fnam = lastFolderIn("google-apps-script-cheat-sheet-demo/files");
var arr_fnam  = filesIn(fldr_fnam);
Logger.log(fileNames(arr_fnam)); // [example-file]

/**
 * Returns a file found at the top level of a folder. 
 *
 * @requires filesIn()
 * @requires fileNames()
 * @requires checkValIn()
 * @param {Folder} fldr
 * @param {string} name
 * @returns {File}
 */

function findFileIn(fldr, name) {
  var files = filesIn(fldr);
  var names = fileNames(files);
  if (checkValIn(names, name)) {
    var file = fldr.getFilesByName(name).next();
    return file;
  }
}

var fldr_ffi = lastFolderIn("google-apps-script-cheat-sheet-demo/files");
Logger.log(findFileIn(fldr_ffi, "example-file")); // example-file

/**
 * Returns a file found at the root of a user's Drive.
 *
 * @requires rootFiles()
 * @requires fileNames()
 * @requires checkValIn()
 * @param {string} name
 * @returns {File}
 */

function findFileAtRoot(name) {
  var rf    = DriveApp.getRootFolder();
  var files = rootFiles();
  var names = fileNames(files);
  if (checkValIn(names, name)) {
    var file = rf.getFilesByName(name).next();
    return file;
  }
}

/**
 * Returns the first matching file found in the user's Drive.
 *
 * @param {string} name
 * @returns {File}
 */

function findFileInDrive(name) {
  var fi = DriveApp.getFilesByName(name);
  while (fi.hasNext()){
    var file = fi.next();
    return file;
  }
}

Logger.log(findFileInDrive("example-file")); // example-file

/**
 * Returns the file found at the end of a path.
 *
 * @param {string} path
 * @returns {File}
 */

function findFileAtPath(path) {
  var fi;
  var split = path.split('/');
  var file  = split[split.length -1];
  var fldr;
  for (i = 0; i < split.length - 1; i++) {
    if (i === 0) {
      fi = DriveApp.getRootFolder().getFoldersByName(split[i]);
      if (fi.hasNext()) {
        fldr = fi.next();
      } else { 
        return null;
      }
    } else if (i >= 1) {
        fi = fldr.getFoldersByName(split[i]);
        if (fi.hasNext()) {
          fldr = fi.next();
        } else { 
          return null;
        }
    }
  } 
  return findFileIn(fldr, file);
} 

Logger.log(findFileAtPath("google-apps-script-cheat-sheet-demo/files/example-file"));

/**
 * Returns the copied file.
 *
 * @requires findFileIn()
 * @param {File} file
 * @param {Folder} fldr
 * @returns {File}
 */

function copyFile(file, fldr) {
  var name = file.getName();
  var dest = findFileIn(fldr, name);
  if (dest === undefined) file.makeCopy(name, fldr);
  return findFileIn(fldr, name);
}

var fldr_cf = createVerifyPath("google-apps-script-cheat-sheet-demo/files/copied");
var file_cf = findFileInDrive("example-file");
Logger.log(copyFile(file_cf, fldr_cf)); // example-file

/**
 * Returns the copied file from its new destination.
 *
 * @requires findFileIn()
 * @param {File} file
 * @param {Folder}  fldr
 * @returns {File}
 */

function moveFile(file, fldr) {
  var name = file.getName();
  var dest = findFileIn(fldr, name);
  if (dest === undefined) file.makeCopy(name, fldr);
  var _file = findFileIn(fldr, name);
  if (_file !== undefined) file.setTrashed(true);
  return _file;
}

var fldr_mf1 = lastFolderIn("google-apps-script-cheat-sheet-demo/files/copied");
var file_mf  = findFileIn(fldr_mf1, "example-file");
var fldr_mf2 = createVerifyPath("google-apps-script-cheat-sheet-demo/files/moved");
Logger.log(moveFile(file_mf, fldr_mf2)); // example-file

/**
 * Returns a renamed file or a folder.
 *
 * @param {File || Folder} file_fldr
 * @param {string} name
 * @returns {File || Folder}
 */

function renameFileFldr(file_fldr, name) {
  file_fldr.setName(name);
  return file_fldr;
} 

var fldr_rf = lastFolderIn("google-apps-script-cheat-sheet-demo/files/moved");
var file_rf = findFileIn(fldr_rf, "example-file");
Logger.log(renameFileFldr(file_rf, "modified-example-file")); // modified-example-file

/**
 * Returns the parent folder or a file or a folder.
 *
 * @param {File || Folder} file_fldr
 * @returns {Folder}
 */

function parentFolderOf(file_fldr) {
  var fi = file_fldr.getParents();
  return fi.next();
}

var file_pfo = findFileInDrive("example-file");
Logger.log(parentFolderOf(file_pfo)); // files

function jsonExFile() {
  var fldr = createVerifyPath("google-apps-script-cheat-sheet-demo/json");
  var file = findFileIn(fldr, "example-json");
  var json = jsonFromUrl("https://raw.githubusercontent.com/jcodesmn/google-apps-script-cheat-sheet/dev/example.json");
  var text = JSON.stringify(json);
  if (!(file)){fldr.createFile("example-json");}
  file.setContent(text);
  return findFileIn(fldr, "example-json");
}

jsonExFile();

/**
 * Returns an object from a URL.
 *
 * @param {string} url
 * @returns {Object}
 */

function objFromUrl(url) {
  var rsp  = UrlFetchApp.fetch(url);
  var data = rsp.getContentText();
  return JSON.parse(data);
} 

var obj_ofu = objFromUrl("https://raw.githubusercontent.com/jcodesmn/google-apps-script-cheat-sheet/dev/example.json");
Logger.log(JSON.stringify(obj_ofu));

/**
 * Returns an object from a file in Drive.
 *
 * @param {File} file
 * @returns {Object}
 */

function objFromFile(file) {
  var data = file.getBlob().getDataAsString();
  return JSON.parse(data);
} 

var file_off = findFileAtPath("google-apps-script-cheat-sheet-demo/json/example-json");
var obj_off  = objFromFile(file_off);
Logger.log(JSON.stringify(obj_off));

/**
 * Returns an object from a URL or from a file in Drive.
 *
 * @param {string || File} input
 * @returns {Object}
 */

function objFromUrlOrFile(input) {
  var regExp = new RegExp("^(http|https)://");
  var test   = regExp.test(input);
  if (test) {
    return objFromUrl(input);
  } else {
    var file = findFileAtPath(input); 
    return objFromFile(file);
  }
}

Logger.log(JSON.stringify(objFromUrlOrFile("https://raw.githubusercontent.com/jcodesmn/google-apps-script-cheat-sheet/dev/example.json")));
Logger.log(JSON.stringify(objFromUrlOrFile("google-apps-script-cheat-sheet-demo/json/example-json")));

/**
 * Returns a spreadsheet. 
 * This creates the spreadsheet if it does not already exist.
 *
 * @requires filesIn()
 * @requires fileNames()
 * @requires checkValIn
 * @requires moveFile()
 * @requires findFileIn()
 * @requires openFileAsSpreadsheet()
 * @param {Folder} fldr
 * @param {string} name
 * @returns {Spreadsheet}
 */

function createVerifySSIn(fldr, name) {
  var files = filesIn(fldr);
  var names = fileNames(files);
  if (!(checkValIn(names, name))) {
    var ss   = SpreadsheetApp.create(name).getId();
    var file = DriveApp.getFileById(ss);
    moveFile(file, fldr);
  }
  return openFileAsSpreadsheet(findFileIn(fldr, name));
}

var fldr_cvssi = createVerifyPath("google-apps-script-cheat-sheet-demo/sheets");
Logger.log(createVerifySSIn(fldr_cvssi, "example-sheet")); // example-sheet

/**
 * Returns a spreadsheet. 
 * This creates the spreadsheet if it does not already exist.
 *
 * @requires rootFiles()
 * @requires fileNames()
 * @requires checkValIn() 
 * @requires findFileAtRoot() 
 * @requires openFileAsSpreadsheet() 
 * @param {string} name
 * @returns {Spreadsheet}
 */

function createVerifySSAtRoot(name) {
  var files = rootFiles();
  var names = fileNames(files);
  if (!(checkValIn(names, name))) {
    var ss = SpreadsheetApp.create(name);
  }
  return openFileAsSpreadsheet(findFileAtRoot(name));
}

/**
 * Returns the Id of the active spreadsheet.
 *
 * @returns {string}
 */

function ssId() {
  var _id = SpreadsheetApp.getActiveSpreadsheet().getId();
  return _id;
}

Logger.log(ssId());

/**
 * Returns the column number as a alphabetical column value.
 * Columns are indexed from 1, not from 0.
 * "CZ" (104) is the highest supported value.
 *
 * @param {number} number
 * @returns {string}
 */

function numCol(number) {
  var num = number - 1, chr;
  if (num <= 25) {
    chr = String.fromCharCode(97 + num).toUpperCase();
    return chr;
  } else if (num >= 26 && num <= 51) {
    num -= 26;
    chr = String.fromCharCode(97 + num).toUpperCase();
    return "A" + chr;
  } else if (num >= 52 && num <= 77) {
    num -= 52;
    chr = String.fromCharCode(97 + num).toUpperCase();
    return "B" + chr;
  } else if (num >= 78 && num <= 103) {
    num -= 78;
    chr = String.fromCharCode(97 + num).toUpperCase();
    return "C" + chr;
  }
}

function ex_nc() {
 for (var i = 1; i <= 104; i++) {
   var j = numCol(i);
   Logger.log(i + " - " + j);
 }
}

ex_nc(); // 1 - A ... CZ - 104

/**
 * Returns an alphabetical column value as a number.
 *
 * @param {string} column
 * @returns {number}
 */

function colNum(column) {
  var col = column.toUpperCase(), chr0, chr1;
  if (col.length === 1)  {
    chr0 = col.charCodeAt(0) - 64;
    return chr0;
  } else if (col.length === 2) {
    chr0 = (col.charCodeAt(0) - 64) * 26;
    chr1 = col.charCodeAt(1) - 64;
    return chr0 + chr1;
  }
}

function ex_cn() {
 for (var i = 0; i <= 25; i++) {
   var abc = String.fromCharCode(97 + i).toUpperCase();
   Logger.log(abc + " - " + colNum(abc));
 }
 for (var i = 26; i <= 51; i++) {
   var abc = "A" + String.fromCharCode(97 - 26 + i).toUpperCase();
   Logger.log(abc + " - " + colNum(abc));
 }
}

ex_cn(); // A - 1 ... AZ - 52

/**
 * Replicating import range in Google Apps Script.
 * Requires a trigger to function.
 * importRange : From spreadsheet : On edit
 *
 */

function importRange(){
  var get = sheet_gs.getRange("A2:A5").getValues();
  var set = sheet_gs.getRange("B2:B5").setValues(get);
}

/**
 * Returns true or false given truthy or falsy values.
 * true: 1, t*, T*, y*, Y*
 * false: 0, !t, || !y
 *
 * @param {string} input
 * @returns {boolean}
 */

function checkTF(input) {
  if (isNaN(input)) {
    var first_letter = input.charAt(0).toLowerCase();
    if (first_letter === 't' || first_letter === 'y') {
      return true;
    } else {
      return false;
    }
  } else {
    if (input === 1) {
      return true;
    } else { 
      return false;
    }
  }
}

Logger.log(checkTF("No")); // false
Logger.log(checkTF("Yes")); // true

/**
 * Returns an array of the sheet names for a spreadsheet.
 *
 * @param {Spreadsheet} ss
 * @returns {string[]}
 */

function arrSheetNames(ss) {
  var sheets = ss.getSheets();
  var arr    = [];
  for (var i = 0; i < sheets.length; i++) {
    arr.push(sheets[i].getName());
  } 
  return arr;
} 

var ss_asn = SpreadsheetApp.getActiveSpreadsheet();
Logger.log(arrSheetNames(ss_asn)); // ["Sheet1", "Sheet2", "Sheet3"]

/**
 * Returns an object from a range.
 * The top row of the range is assumed to be the header row.
 * Values in the header row become the object properties.
 *
 * @param {Sheet} sheet
 * @param {string} a1Notation
 * @returns {Object}
 */

function objFromRange(sheet, a1Notation) {
  var range  = sheet.getRange(a1Notation);
  var height = range.getHeight();
  var width  = range.getWidth();
  var values = range.getValues();
  var obj    = {};
  for (var i = 0; i < values.length; i++) {
    obj[values[i][0]] = values[i][1];
  } 
  return obj;
}

var sheet_ofr = SpreadsheetApp.getActiveSpreadsheet().getSheetByName("Sheet1");
Logger.log(objFromRange(sheet_ofr, "D2:E5")); // {A=Alpha, B=Bravo, C=Charlie, D=Delta}

/**
 * Returns an array of values for the top row of a range object.
 *
 * @param {Range} rangeObj
 * @returns {Array}
 */

function headerVal(rangeObj){
  var vals = rangeObj.getValues();
  var arr  = [];
  for (var i = 0; i < vals[0].length; i++) {
    var val = vals[0][i];
    arr.push(val);
  } 
  return arr;
}

var sheet_hv = SpreadsheetApp.getActiveSpreadsheet().getSheetByName("Sheet2");
var range_hv = sheet_hv.getRange("A2:E19");
Logger.log(headerVal(range_hv)); // ["First", "Last", "Grade", "Homeroom", "Email"]

/**
 * Returns an array of objects representing a range.
 *
 * @param {Range} rangeObj
 * @param {Array} headers
 * @returns {Object[]}
 */

function valByRow(rangeObj, headers){
  var height = rangeObj.getHeight();
  var width  = rangeObj.getWidth();
  var vals   = rangeObj.getValues();
  var arr  = [];
  for (var i = 0; i < height; i++) {
    var row = {};
    for (var j = 0; j < width; j++) {
      var prop = headers[j];
      var val  = vals[i][j];
      if (val !== "") {
        row[prop] = val;
      } 
    }
    arr.push(row);
  }  
  return arr;
}

var sheet_vbr   = SpreadsheetApp.getActiveSpreadsheet().getSheetByName("Sheet2");
var range_vbr   = sheet_hv.getRange("A2:E19");
var headers_vbr = headerVal(range_vbr);
Logger.log(valByRow(range_vbr, headers_vbr)); // [{Last=Last, Email=Email, Homeroom=Homeroom, Grade=Grade, First=First}, {Last=Garret, [email protected], Homeroom=Muhsina, Grade=6.0, First=Arienne}...]

/**
 * Returns the header range for a targeted range.
 *
 * @param {Sheet} sheet
 * @param {string} a1Notation
 * @returns {Range}
 */

function headerRange(sheet, a1Notation) {
  var split = a1Notation.split(":");
  var col0  = split[0].match(/\D/g,'');
  var col1  = split[1].match(/\D/g,'');
  var row   = split[0].match(/\d+/g);
  var a1    = col0 + row + ":" + col1 + row;
  return sheet.getRange(a1);
}

var sheet_hr = SpreadsheetApp.getActiveSpreadsheet().getSheetByName("Sheet2");
Logger.log(headerRange(sheet_hr, "A2:E19").getA1Notation()); // "A2:E2"
Logger.log(headerRange(sheet_hr, "A2:E19").getValues()); // [[First, Last, Grade, Homeroom, Email]]

/**
 * Returns the value range for a targeted range. 
 *
 * @param {Sheet} sheet
 * @param {string} a1Notation
 * @returns {Range}
 */

function valueRange(sheet, a1Notation) {
  var split = a1Notation.split(":");
  var col0  = split[0].match(/\D/g,'');
  var row0  = split[0].match(/\d+/g);
  var col1  = split[1].match(/\D/g,'');
  var row1  = split[1].match(/\d+/g);
  var a1    = col0 + (Number(row0) + 1) + ":" + col1 + row1;
  return sheet.getRange(a1);
}

var sheet_vr = SpreadsheetApp.getActiveSpreadsheet().getSheetByName("Sheet2");
Logger.log(valueRange(sheet_vr, "A2:E19").getA1Notation()); // "A3:E19"
Logger.log(valueRange(sheet_vr, "A2:E19").getValues()); // [[Arienne, Garret, 6.0, Muhsina, [email protected]], [Elissa, Jules, 6.0, Lale, [email protected]]...]

/**
 * Returns an array of objects representing the values in a sheet.
 *
 * @requires numCol() 
 * @requires headerVal() 
 * @requires valByRow() 
 * @param sheet
 * @param hRow
 * @returns {undefined}
 */

function arrObjFromSheet(sheet, hRow){
  var lColNum = sheet.getLastColumn();
  var lColABC = numCol(lColNum);
  var lRow    = sheet.getLastRow();
  var hRange  = sheet.getRange("A" + hRow + ":" + lColABC + hRow);
  var headers = headerVal(hRange);
  var vRange  = sheet.getRange("A" + (hRow +1) + ":" + lColABC + lRow);
  return valByRow(vRange, headers);
}

var sheet_aofs = SpreadsheetApp.getActiveSpreadsheet().getSheetByName("Sheet2");
Logger.log(arrObjFromSheet(sheet_aofs, 2)); // [{Last=Garret, [email protected], Homeroom=Muhsina, Grade=6.0, First=Arienne}, {Last=Jules, [email protected], Homeroom=Lale, Grade=6.0, First=Elissa}...]

/**
 * Returns an array of values representing the values in a range.
 *
 * @requires headerRange() 
 * @requires valueRange() 
 * @requires headerVal() 
 * @requires valByRow() 
 * @param sheet
 * @param a1Notation
 * @returns {undefined}
 */

function arrObjFromRange(sheet, a1Notation) {
  var hRange  = headerRange(sheet, a1Notation);
  var vRange  = valueRange(sheet, a1Notation);
  var headers = headerVal(hRange);
  return valByRow(vRange, headers);
}

var sheet_aofr = SpreadsheetApp.getActiveSpreadsheet().getSheetByName("Sheet2");
Logger.log(arrObjFromRange(sheet_aofr, "A2:E7")); // [{Last=Garret, [email protected], Homeroom=Muhsina, Grade=6.0, First=Arienne}, {Last=Jules, [email protected], Homeroom=Lale, Grade=6.0, First=Elissa}...]

/**
 * Returns an array containing all values in a column.
 *
 * @param {Sheet} sheet
 * @param {number} hRow
 * @param {string} name
 * @returns {Array}
 */

function arrForColName(sheet, hRow, name){
  var lColNum  = sheet.getLastColumn();
  var lColABC  = numCol(lColNum);
  var lRow     = sheet.getLastRow();
  var hRange   = sheet.getRange("A" + hRow + ":" + lColABC + hRow);
  var headers  = headerVal(hRange);
  var tColABC  = numCol(headers.indexOf(name) + 1);
  var rangeObj = sheet.getRange(tColABC + (hRow +1) + ":" + tColABC + lRow);
  var height   = rangeObj.getHeight();
  var vals     = rangeObj.getValues();
  var arr      = [];
  for (var i = 0; i < height; i++) {
      var val  = vals[i][0];
      arr.push(String(val));
  }  
  return arr;
}

var sheet_afcna = SpreadsheetApp.getActiveSpreadsheet().getSheetByName("Sheet2");
Logger.log(arrForColName(sheet_afcna, 2, "First")); // [Arienne, Elissa, Nerses, Gülistan, Syed, Isaiah, Stanley, Sára, Kaja, Józef, Radoslava, Sarah, Oluwasegun, Ekundayo, Gina, Sylvia, Cemil]