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

#include "emotion.h"
#include "journal.h"

#define TOPICS 10

// go through all elements of argv[2] and beyond
// and join them together in a string
char *extract_handler_msg(int argc, char **argv)
{
    int cur = 0;

    // allocate an empty slot to start with.
    char *res = malloc(cur);

    // iterate through each argument
    for(int i = 2; argv[i] != NULL; i++)
    {
        // catch it, get its length
        char *word = argv[i];
        int wordlen = strlen(word);

        // increase the size of our current things by
        // arg length + 1 (for a whitespace)
        cur += wordlen;
        res = realloc(res, cur + 1);

        // only prepend our whitespace if we AREN'T
        // at the first argument.
        if(i != 2)
        {
            res[cur - wordlen] = ' ';
            cur++;
        }

        // merge our current results with the current arg
        for(int j = 0; j < wordlen; j++)
        {
            res[cur - wordlen + j] = word[j];
        }
    }

    return res;
}

int main(int argc, char** argv)
{
    if(argc < 2)
    {
        printf("usage: %s topic message\n", argv[0]);
        return 0;
    }

    char *topic = argv[1];

    const char* topics[TOPICS] = {
        "emotion"
    };

    void (*handlers[])(FILE*, char*) = {
        handle_emotion,
    };

    if(strcmp(topic, "list") == 0)
    {
        // list all topics
        for(int i = 0; topics[i] != NULL; i++)
            printf("%s ", topics[i]);
        printf("\n");
        return 0;
    }

    for(int i = 0; topics[i] != NULL; i++)
    {
        const char* cur_topic = topics[i];

        if(strcmp(topic, cur_topic) == 0)
        {
            void (*fun_ptr)(FILE*, char*) = handlers[i];

            FILE* journal_file = journal_open(topic);

            char *handler_message = extract_handler_msg(argc, argv);
            printf("'%s'\n", handler_message);

            // the joined args[2] and beyond come as the
            // second argument
            fun_ptr(journal_file, handler_message);
            journal_close(journal_file);

            free(handler_message);
            printf("done\n");
            return 0;
        }
    }

    printf("topic %s not found\n", topic);
    return 0;
}