Given an object of social media metrics, returns certain stats.

social.js

const biggestFollower = function (data) {
  let bigFollow = { name: "", followCount: 0 }
  for (let id in data) {
    if (data[id]['follows'].length > bigFollow.followCount) {
      bigFollow.name = data[id]['name'];
      bigFollow.followCount = data[id]['follows'].length;
    }
  }

  console.log(`${bigFollow.name} follows the most people (${bigFollow.followCount}).`);
  return bigFollow.name;
};

const mostPopular = function (data) {
  let followerCount = {};

  // Create list of how many followers each ID has.
  for (let id in data) {
    for (let i = 0; i <= data[id]['follows'].length - 1; i++) {
      if (!followerCount[data[id]['follows'][i]]) {
        followerCount[data[id]['follows'][i]] = 1;
      } else {
        followerCount[data[id]['follows'][i]] += 1;
      }
    }
  }

  // Find the number of the most amount of followers
  let mostFollows = 0;
  for (let id in followerCount) {
    // console.log(followerCount[id])
    if (followerCount[id] > mostFollows) {
      mostFollows = followerCount[id];
    }
  }

  //Create object for all users with that amount of followers (some are tied)
  const mostPopularUsers = {};
  for (let id in followerCount) {
    if (followerCount[id] === mostFollows) {
      for (let userID in data) {
        if (id === userID) {
          mostPopularUsers[data[userID]['name']] = mostFollows;
        }
      }
    }
  }

  console.log("User(s) with the most followers:");
  console.log(mostPopularUsers);

  return mostPopularUsers;
};

const nameIDDatabase = function (data) {
  // Create an object with ID/Name pairing.
  const database = {};
  for (let id in data) {
    database[id] = data[id]['name'];
  }
  return database;
};

const unrequitedFol = function (data) {
  let unReqList = [];
  // will print ["Avery follows Alex, but he doesn't follow back", "Alex follows..."]
  let followData = printAll(data);
  for (let user in followData) {
    for (let i = 0; i <= followData[user]['Following'].length - 1; i++) {
      let flag = 0;
      for (let j = 0; j <= followData[user]['Followers'].length - 1; j++) {
        if (followData[user]['Following'][i] === followData[user]['Followers'][j]) {
          flag += 1;
        }
      }
      if (flag === 0) {
        unReqList.push(`${user} follows ${followData[user]['Following'][i]} but they don't follow back!`);
      }
    }
  }
  console.log(unReqList);
  return unReqList;
};

const printAll = function (data) {
  const followData = {};
  const database = nameIDDatabase(data);

  // initialize followData array with names, and array for names of followers and following
  for (let id in data) {
    followData[data[id]['name']] = { Following: [], Followers: [] };
  }

  // Loop through each ID and populate following/follower arrays.
  for (let id in data) {
    for (let i = 0; i <= data[id]['follows'].length - 1; i++) {
      let followingID = data[id]['follows'][i];
      let followingName = database[followingID];
      followData[data[id]['name']]['Following'].push(followingName);
      followData[followingName]['Followers'].push(data[id]['name']);
    }
  }
  // console.log(followData);
  return followData;
};

const followerOver30 = function (data) {
  // Who has most followers over 30
  let database = nameIDDatabase(data);

  // create list of ID's with followers over 30
  let followOver30Obj = {};
  for (let id in data) {
    if (data[id].age > 30) {
      for (let i = 0; i <= data[id]['follows'].length - 1; i++) {
        if (followOver30Obj[data[id]['follows'][i]]) {
          followOver30Obj[data[id]['follows'][i]] += 1;
        } else {
          followOver30Obj[data[id]['follows'][i]] = 1;
        }
      }
    }
  }

  // find ID with most followers
  // convert ID to name
  let over30Count = 0;
  let name = "";
  for (let id in followOver30Obj) {
    if (followOver30Obj[id] > over30Count) {
      over30Count = followOver30Obj[id];
      name = database[id];
    }
  }

  console.log(`${name} has the most followers over 30 (${over30Count})`);
  return name;
};

const followOver30 = function (data) {
  let database = nameIDDatabase(data);

  let idListOver30 = [];
  for (let id in data) {
    if (data[id].age > 30) {
      idListOver30.push(id);
    }
  }

  let followingOver30Obj = {};
  for (let id in data) {
    for (let x of data[id].follows) {
      for (let y of idListOver30) {
        if (x === y) {
          if (followingOver30Obj[id]) {
            followingOver30Obj[id] += 1;
          } else {
            followingOver30Obj[id] = 1;
          }
        }
      }
    }
  }

  let followCount = 0;
  let name = "";
  for (let id in followingOver30Obj) {
    if (followingOver30Obj[id] > followCount) {
      followCount = followingOver30Obj[id];
      name = database[id];
    }
  }

  console.log(`${name} follows the most people over 30 (${followCount})`);
  return name;
};

const userReach = function (data) {
  let followData = printAll(data);
  // console.log(followData);
  let database = nameIDDatabase(data);
  let reach = {};

  // create list of each persons followers
  for (let name in followData) {
    reach[name] = followData[name]['Followers'];
    
  };

  // add followers of followers
  for (let name in reach) {
    for (let follower of reach[name]) {
      reach[name] = reach[name].concat(followData[follower]['Followers']);
    }
  }

  // remove duplicates and same name
  for (let name in reach) {
    let newArray = reach[name].filter((item, index) => reach[name].indexOf(item) === index);
    reach[name] = newArray.filter(person => person !== name);
  }

  let reachCount = {};
  for (let name in reach) {
    reachCount[name] = reach[name].length;
  }
  // console.log(reach);
  console.log("Reach count");
  console.log(reachCount);
};

const data = {
  f01: {
    name: "Alice",
    age: 15,
    follows: ["f02", "f03", "f04", "f07", "f05"]
  },
  f02: {
    name: "Bob",
    age: 20,
    follows: ["f05", "f06", "f07"]
  },
  f03: {
    name: "Charlie",
    age: 35,
    follows: ["f01", "f04", "f06"]
  },
  f04: {
    name: "Debbie",
    age: 40,
    follows: ["f01", "f02", "f03", "f05", "f06", "f07"]
  },
  f05: {
    name: "Elizabeth",
    age: 45,
    follows: ["f04", "f07"]
  },
  f06: {
    name: "Finn",
    age: 25,
    follows: ["f05", "f07"]
  },
  f07: {
    name: "Alex",
    age: 27,
    follows: []
  }
};

biggestFollower(data);
mostPopular(data);
printAll(data);
nameIDDatabase(data);
unrequitedFol(data);
followerOver30(data);
followOver30(data);
userReach(data);