#!/usr/bin/env python3
# -*- coding: utf-8 -*-
"""
Felix Muzny
10/21/2022
DS 2000
Lecture 13 - functions and program design, HW 5 help

A program to read and analyze some small weather data
"""

WEATHER_DATA = "weather_sample.csv"

def read_data(filename, skip_header = False):
    """
    Reads in the data in a given file
    and stores the values in a list of lists of strings.
    Assumes that commas separate row items in the given file.

    Parameters
    ----------
    filename : string
        name of the file
    skip_header: boolean, optional
        whether or not to skip a header row. Default to False.
    Returns
    -------
    data : list of lists
        list of lists of string values for all lines in the file

    """
    file = open(filename, "r")
    data = []
    # do we need to skip the first row?
    if skip_header:
        file.readline()
        
    for line in file:
        pieces = line.strip().split(",")

        # replace empty strings with 0s (for all columns)        
        # we know empty strings happen in this column
        # use a for loop if you want to do this for all columns!
        if pieces[2] == "":
            pieces[2] = "0.0"
        
        # change temp to ints
        pieces[1] = int(pieces[1])
        
        # change precip to floats
        pieces[2] = float(pieces[2])
        
        # change temp to celcius
        # C = 5/9(F-32)
        pieces[1] = (5/9) * (pieces[1] - 32)
        
        # make sure I only have the data that I want?
        # build a new list for this row
        row = [pieces[0], pieces[1], pieces[2]]
        
        data.append(row)
        
    return data

def main():
    print("fake HW 5/Weather data analysis")
    weather_data = read_data(WEATHER_DATA, skip_header=True)
    print(weather_data[:4])
    
main()