'''
    DS2000
    Spring 2023
    Sample code from class - March 3rd
    1. given a state, how many students are from there?
    2. which state has the most students at NEU?
'''


import csv

STATE_FILE = "neu_geography.csv"

def read_csv(filename):
    ''' Function: read_csv
        Parameter: filename, a string
        Returns: dictionary of key, value pairs
        Does: iterate over the file, first in every row
              beomes key, second thing becomes value (int)
    '''
    data = {}
    with open(filename, "r") as infile:
        csvfile = csv.reader(infile)
        next(csvfile)
        for row in csvfile:
            data[row[0]] = int(row[1])
    return data

def find_max(dct):
    ''' Function: find_max
        Parameter: dictionary where keys can be anything,
                   values are non-neg numbers
        Return: max value and its key
        Does: iterate over the dictionary, find highest
              value and return that with its key
    '''
    max_val = -1
    max_key = ""
    for key, value in dct.items():
        if value > max_val:
            max_val = value
            max_key = key
    return max_key, max_val 
    
    

def main():
    # Gather data - read from the csv file into a dictionary
    dct = read_csv(STATE_FILE)
    
    # 1. given a state, how many people are from there?
    state = input("Which state?\n")
    num_students = 0
    if state in dct:
        num_students = dct[state]
    
    # 2. which state has the most students here?
    max_state, max_num = find_max(dct)
    
    # Communication - print out results
    print("There are", num_students, "from", state)
    print("State with the most is.....", max_state,
          "with....", max_num, "students")
    print("Total students this year:", sum(dct.values()))
    
    
main()