/**
 * Structs and weather data
 * This program takes three approaches to filling structs
 * Two of which actually work!
 * @author gtowell
 * Created: Fall 2019
 * Considerably changed: March 2021
 * **/

/**
 * to select between three methods
 * gcc -D METHOD=[123] weather.c
 **/

// select among the various struct fillers
#ifndef METHOD
#define METHOD 1
#endif

#ifndef NULL
#define NULL (void *)0
#endif


#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#define WFILE "temps.txt"

/**
 * A struct for grouping together weather data
 * **/
typedef struct {
    char time[10];
    int temp;
    int dewPoint;
    int relHum;
    char windDir[10];
    int windSpeed;
} WeatherData;

// An array holding lots of weather data
WeatherData weather[100];

/**
 * A print representation of weather data 
 * @param w -- the weather data to be printed
 * **/
void wprinter(WeatherData* w)
{
    printf("%d Time:%s  Temp:%d F\n", w, w->time, w->temp);
}

// Point here is the structs are pass by value!!!!
/**
 * Parse the passed in line into the passed in struct
 * This really fills the struct, but it does not
 * matter because the struct is passed by value!
 * @param line -- the data to be parsed
 * @param w -- the struct to be filled
 * **/
void parseA(char* line, WeatherData w)
{
    //printf("WaP %d\n", &w);
    char* c = strtok(line, " \t");
    strcpy(w.time, c);
    strtok(NULL, " \t"); // AM / PM skipped
    c = strtok(NULL, " \t");
    w.temp = (int)strtol(c, NULL, 10);
    c = strtok(NULL, " \t");
    c = strtok(NULL, " \t");
    w.dewPoint = (int)strtol(c, NULL, 10);
    c = strtok(NULL, " \t");
    c = strtok(NULL, " \t");
    w.relHum = (int)strtol(c, NULL, 10);
    c = strtok(NULL, " \t");
    strcpy(w.windDir, c);
    c = strtok(NULL, " \t");
    c = strtok(NULL, " \t");
    w.windSpeed = (int)strtol(c, NULL, 10);
}

/**
 * Parse the passed in line a struct
 * This really fills the struct, 
 * which is then returned by value.
 * @param line -- the data to be parsed
 * @return a filled structure
 * **/
WeatherData parseB(char* line)
{
    WeatherData w;
    char* c = strtok(line, " \t");
    strcpy(w.time, c);
    strtok(NULL, " \t"); // AM / PM skipped
    c = strtok(NULL, " \t");
    w.temp = (int)strtol(c, NULL, 10);
    c = strtok(NULL, " \t");
    c = strtok(NULL, " \t");
    w.dewPoint = (int)strtol(c, NULL, 10);
    c = strtok(NULL, " \t");
    c = strtok(NULL, " \t");
    w.relHum = (int)strtol(c, NULL, 10);
    c = strtok(NULL, " \t");
    strcpy(w.windDir, c);
    c = strtok(NULL, " \t");
    c = strtok(NULL, " \t");
    w.windSpeed = (int)strtol(c, NULL, 10);
    return w;
}

/**
 * Parse the passed in line into a WeatherData object
 * that is passed as a pointer!
 * @param line -- the data to be parsed
 * @param w -- a pointer to a struct to be filled
 * **/
void parseC(char* line, WeatherData * w)
{
    char* c = strtok(line, " \t");
    strcpy(w->time, c);
    strtok(NULL, " \t"); // AM / PM skipped
    c = strtok(NULL, " \t");
    w->temp = (int)strtol(c, NULL, 10);
    c = strtok(NULL, " \t");
    c = strtok(NULL, " \t");
    w->dewPoint = (int)strtol(c, NULL, 10);
    c = strtok(NULL, " \t");
    c = strtok(NULL, " \t");
    w->relHum = (int)strtol(c, NULL, 10);
    c = strtok(NULL, " \t");
    strcpy(w->windDir, c);
    c = strtok(NULL, " \t");
    c = strtok(NULL, " \t");
    w->windSpeed = (int)strtol(c, NULL, 10);
    //printf("WbP %d\n", &w);
}

/**
 * Print a header to identify the method being used
 * **/
void doHeader() {
    for (int i = 0; i < 10; i++)
        printf("%d", METHOD);
    printf("\n");
}

int main(void)
{
    doHeader();
    char line[256];
    FILE* f = fopen(WFILE, "r");
    if (f==NULL) {
    	fprintf(stderr, "Could not open %s -- quitting\n", WFILE);
	    return 1;
    }
    int c = 0;
    while (NULL != fgets(line, 256, f))
    {
        switch (METHOD) {
            case 1:
            	parseA(line, weather[c]);
                break;
            case 2:
                weather[c] = parseB(line);
                break;
            case 3:
            default:
                parseC(line, &weather[c]);
                break;
            }
	    c++;
    }
    for (int i=0; i<c; i++) {
	    wprinter(&weather[i]);
    }
    doHeader();
}