#define _GNU_SOURCE
#include <mysql/mysql.h>
#include <stdio.h>
#include <stdlib.h>
#include <stdbool.h>
#include <malloc.h>

static MYSQL* conn2maria();
static int AddPost(char title[], int authorId, char datePosted[], char post[], int tags[], size_t tagSize, MYSQL* con);
static int EditPost(int postID, char title[], char post[], MYSQL* con);
static int PullPostData(char* strings[6], int postID, MYSQL* con);
static int AddTag(char tagTitle[], MYSQL* con);
static int DeleteTag(int tagID, MYSQL* con);
static int EditTag(int tagID, char tagTitle[], MYSQL* con);
static int AssignTag(int tagID, int postID, MYSQL* con);
static int RetractTag(int tagID, int postID, MYSQL* con);
static int AddAuthor(char firstName[], char lastName[], char email[], MYSQL* con);
static int PullAuthorData(char* strings[4], int authorID, MYSQL* con);
static int ChangeAuthor(int postID, int authorID, MYSQL* con);
static int TogglePost(int postID, MYSQL* con);
static bool IsEnabled(int postID, MYSQL* con);

// Connects to the MariaDB database and returns the connection 
MYSQL* conn2maria()
{
    // Initialize the connection
    MYSQL *con = mysql_init(NULL);

    // If successful, continue, else throw error
    if (con == NULL) 
    {
        fprintf(stderr, "%s\n", mysql_error(con));
        exit(1);
    }

    // Connect with specific details, if successful continue, else throw error
    if (mysql_real_connect(con, "localhost", "adam", "1234", 
          "mydb", 0, NULL, 0) == NULL) 
    {
        fprintf(stderr, "%s\n", mysql_error(con));
        mysql_close(con);
        exit(1);
    }

    // return successful connection
    return con;
}

// Adds a new post to the database, with given values
int AddPost(char title[], int authorId, char datePosted[], char post[], int tags[], size_t tagSize, MYSQL* con)
{
    if (con == NULL) 
    {
        con = conn2maria();
    }

    // Build a query
    char* query;
    if(0 > asprintf(&query, 
        "INSERT INTO blog_posts (title,author_id,date_posted,post,state) VALUES (\"%s\", \"%d\", \"%s\", \"%s\", \"0\")",
        title,
        authorId,
        datePosted,
        post
    )) exit(1);

    // Query the server, if successful continue, else throw error
    if (mysql_query(con, query)) 
    {
        fprintf(stderr, "%s\n", mysql_error(con));
        mysql_close(con);
        exit(1);
    }

    // Free the memory of the query string
    free(query);


    if (mysql_query(con, "SELECT LAST_INSERT_ID()"))
    {
        fprintf(stderr, "%s\n", mysql_error(con));
        mysql_close(con);
        exit(1);
    }

    // Get results
    MYSQL_RES *result = mysql_store_result(con);
    int num_fields = mysql_num_fields(result);

    // For all rows (only one ;P)
    MYSQL_ROW row;
    row = mysql_fetch_row(result);
    int output = atoi(row[0]);

    // Ignore all if tags is NULL pointer
    if (tags != NULL)
    {
        //printf("%d\n", tagSize / sizeof(int));
        // for the size of tags
        for (int i = 0; i < tagSize / sizeof(int); i++)
        {
            printf("%d\n", i);

            AssignTag(tags[i], output, con);
        }
    }

    return output;
}

// Edits a post in the database, to the new given values
int EditPost(int postID, char title[], char post[], MYSQL* con)
{
    if (con == NULL) 
    {
        con = conn2maria();
    }

    char* selectQuery;
    if(0 > asprintf(&selectQuery, 
        "SELECT * FROM blog_posts WHERE id=(%d)", 
        postID
    )) exit(1);

    // Query the server, if successful continue, else throw error
    if (mysql_query(con, selectQuery)) 
    {
        fprintf(stderr, "%s\n", mysql_error(con));
        mysql_close(con);
        exit(1);
    }

    // Get results
    MYSQL_RES *result = mysql_store_result(con);
    int num_fields = mysql_num_fields(result);

    if (result == NULL) {
        printf("Hey\n");
    }    

    MYSQL_ROW row;
    int tagFound = 1;
   
   
    if (mysql_fetch_row(result) == NULL)
    {
        printf("Hey4\n");
        tagFound = 0;
    }

    free(selectQuery);

    char* updateQuery;

    if (!tagFound) { return postID; }

    // Build a query
    if (0 > asprintf(&updateQuery, "UPDATE blog_posts SET title=(\"%s\"), post=(\"%s\") WHERE id=(%d)",
        title,
        post,
        postID
    )) exit(1);
   
    // Query the server, if successful continue, else throw error
    if (mysql_query(con, updateQuery)) 
    {
        fprintf(stderr, "%s\n", mysql_error(con));
        mysql_close(con);
        exit(1);
    }

    free(updateQuery);

    return postID;
}

// Pulls a single post's data into the supplied array
int PullPostData(char* strings[6], int postID, MYSQL* con)
{
    if (con == NULL) 
    {
        con = conn2maria();
    }

    // Build a query
    char* query;
    if(0 > asprintf(&query, "SELECT * FROM blog_posts WHERE id=(%d)", postID)) exit(1);

    // Query the server, if successful continue, else throw error
    if (mysql_query(con, query)) 
    {
        fprintf(stderr, "%s\n", mysql_error(con));
        mysql_close(con);
        exit(1);
    }

    // Free the memory of the query string
    free(query);

    // Get results
    MYSQL_RES *result = mysql_store_result(con);
    int num_fields = mysql_num_fields(result);

    // For all rows (only one ;P)
    MYSQL_ROW row;
    while ((row = mysql_fetch_row(result)))
    {
        // For all fields in row
        for(int i = 0; i < num_fields; i++)
        {
            // 'return' the output
            strings[i] = row[i];
        }

    }

    return postID;
}

// Adds a tag
int AddTag(char tagTitle[], MYSQL* con)
{
    if (con == NULL) 
    {
        con = conn2maria();
    }

    char* insertQuery;

    // Build a query
    if (0 > asprintf(&insertQuery, "INSERT INTO tags (name) VALUES (\"%s\")",
        tagTitle
    )) exit(1);
   
    // Query the server, if successful continue, else throw error
    if (mysql_query(con, insertQuery)) 
    {
        fprintf(stderr, "%s\n", mysql_error(con));
        mysql_close(con);
        exit(1);
    }

    free(insertQuery);

    if (mysql_query(con, "SELECT LAST_INSERT_ID()"))
    {
        fprintf(stderr, "%s\n", mysql_error(con));
        mysql_close(con);
        exit(1);
    }

    // Get results
    MYSQL_RES *result = mysql_store_result(con);
    int num_fields = mysql_num_fields(result);

    // For all rows (only one ;P)
    MYSQL_ROW row;
    row = mysql_fetch_row(result);
    int output = atoi(row[0]);

    return output;
}

// Removes a tag, and unassigns itself from any and all posts.
int DeleteTag(int tagID, MYSQL* con)
{
    if (con == NULL) 
    {
        con = conn2maria();
    }

    char* deleteQuery;

    // Build a query
    if (0 > asprintf(&deleteQuery, "DELETE FROM tags WHERE id=(%d)",
        tagID
    )) exit(1);
   
    // Query the server, if successful continue, else throw error
    if (mysql_query(con, deleteQuery)) 
    {
        fprintf(stderr, "%s\n", mysql_error(con));
        mysql_close(con);
        exit(1);
    }

    free(deleteQuery);

    char* deleteTagsQuery;

    // Build a query
    if (0 > asprintf(&deleteTagsQuery, "DELETE FROM blog_post_tags WHERE tag_id=(%d)",
        tagID
    )) exit(1);
   
    // Query the server, if successful continue, else throw error
    if (mysql_query(con, deleteTagsQuery)) 
    {
        fprintf(stderr, "%s\n", mysql_error(con));
        mysql_close(con);
        exit(1);
    }

    free(deleteTagsQuery);

    return tagID;
}

// Edit the tag name
int EditTag(int tagID, char tagTitle[], MYSQL* con)
{

    if (con == NULL) 
    {
        con = conn2maria();
    }

    char* selectQuery;
    if(0 > asprintf(&selectQuery, 
        "SELECT * FROM tags WHERE id=(%d)", 
        tagID
    )) exit(1);

    // Query the server, if successful continue, else throw error
    if (mysql_query(con, selectQuery)) 
    {
        fprintf(stderr, "%s\n", mysql_error(con));
        mysql_close(con);
        exit(1);
    }

    // Get results
    MYSQL_RES *result = mysql_store_result(con);
    int num_fields = mysql_num_fields(result);

    MYSQL_ROW row;
    int tagFound = 1;
   
   
    if (mysql_fetch_row(result) == NULL)
    {
        tagFound = 0;
    }

    free(selectQuery);

    char* updateQuery;

    if (!tagFound) { return tagID; }

    // Build a query
    if (0 > asprintf(&updateQuery, "UPDATE tags SET name=(\"%s\") WHERE id=(%d)",
        tagTitle,
        tagID
    )) exit(1);
   
    // Query the server, if successful continue, else throw error
    if (mysql_query(con, updateQuery)) 
    {
        fprintf(stderr, "%s\n", mysql_error(con));
        mysql_close(con);
        exit(1);
    }

    free(updateQuery);

    return tagID;
}

// Assign a post a given tag.
int AssignTag(int tagID, int postID, MYSQL* con)
{
    if (con == NULL) 
    {
        con = conn2maria();
    }

    char* selectQuery;
    if(0 > asprintf(&selectQuery, 
        "SELECT * FROM blog_post_tags WHERE tag_id=(%d) AND blog_post_id=(%d)", 
        tagID, 
        postID
    )) exit(1);

    // Query the server, if successful continue, else throw error
    if (mysql_query(con, selectQuery)) 
    {
        fprintf(stderr, "%s\n", mysql_error(con));
        mysql_close(con);
        exit(1);
    }

    // Get results
    MYSQL_RES *result = mysql_store_result(con);
    int num_fields = mysql_num_fields(result);

    if (result == NULL) {
        printf("Hey\n");
    }    

    MYSQL_ROW row;
    int tagFound = 1;
   
   
    if (mysql_fetch_row(result) == NULL)
    {
        printf("Hey4\n");
        tagFound = 0;
    }

    free(selectQuery);

    char* insertQuery;

    if (tagFound) { return postID; }

    // Build a query
    if (0 > asprintf(&insertQuery, "INSERT INTO blog_post_tags (tag_id,blog_post_id) VALUES (%d, %d)", tagID, postID )) exit(1);
   
    // Query the server, if successful continue, else throw error
    if (mysql_query(con, insertQuery)) 
    {
        fprintf(stderr, "%s\n", mysql_error(con));
        mysql_close(con);
        exit(1);
    }

    free(insertQuery);

    return postID;
}

// Unassign a tag from the given post
int RetractTag(int tagID, int postID, MYSQL* con)
{
    if (con == NULL) 
    {
        con = conn2maria();
    }

    char* deleteQuery;

    // Build a query
    if (0 > asprintf(&deleteQuery, "DELETE FROM blog_post_tags WHERE tag_id=(%d) AND blog_post_id=(%d)",
        tagID,
        postID
    )) exit(1);
   
    // Query the server, if successful continue, else throw error
    if (mysql_query(con, deleteQuery)) 
    {
        fprintf(stderr, "%s\n", mysql_error(con));
        mysql_close(con);
        exit(1);
    }

    free(deleteQuery);

    return postID;
}

// Add an author
int AddAuthor(char firstName[], char lastName[], char email[], MYSQL* con)
{
    if (con == NULL) 
    {
        con = conn2maria();
    }

    char* insertQuery;

    // Build a query
    if (0 > asprintf(&insertQuery, "INSERT INTO people (first_name, last_name, email) VALUES (\"%s\", \"%s\", \"%s\")",
        firstName,
        lastName,
        email
    )) exit(1);
   
    // Query the server, if successful continue, else throw error
    if (mysql_query(con, insertQuery)) 
    {
        fprintf(stderr, "%s\n", mysql_error(con));
        mysql_close(con);
        exit(1);
    }

    free(insertQuery);

    if (mysql_query(con, "SELECT LAST_INSERT_ID()"))
    {
        fprintf(stderr, "%s\n", mysql_error(con));
        mysql_close(con);
        exit(1);
    }

    // Get results
    MYSQL_RES *result = mysql_store_result(con);
    int num_fields = mysql_num_fields(result);

    // For all rows (only one ;P)
    MYSQL_ROW row;
    row = mysql_fetch_row(result);
    int output = atoi(row[0]);

    return output;
}

// Pull the full name and email of the given author ID
int PullAuthorData(char* strings[4], int authorID, MYSQL* con)
{
    if (con == NULL) 
    {
        con = conn2maria();
    }

    // Build a query
    char* query;
    if(0 > asprintf(&query, "SELECT * FROM people WHERE id=(%d)", authorID)) exit(1);

    // Query the server, if successful continue, else throw error
    if (mysql_query(con, query)) 
    {
        fprintf(stderr, "%s\n", mysql_error(con));
        mysql_close(con);
        exit(1);
    }

    // Free the memory of the query string
    free(query);

    // Get results
    MYSQL_RES *result = mysql_store_result(con);
    int num_fields = mysql_num_fields(result);

    // For all rows (only one ;P)
    MYSQL_ROW row;
    while ((row = mysql_fetch_row(result)))
    {
        // For all fields in row
        for(int i = 0; i < num_fields; i++)
        {
            // 'return' the output
            strings[i] = row[i];
        }

    }

    return authorID;
}

// Change the author of a given post
int ChangeAuthor(int postID, int authorID, MYSQL* con)
{

    if (con == NULL) 
    {
        con = conn2maria();
    }

    char* selectQuery;
    if(0 > asprintf(&selectQuery, 
        "SELECT * FROM blog_posts WHERE id=(%d)", 
        postID
    )) exit(1);

    // Query the server, if successful continue, else throw error
    if (mysql_query(con, selectQuery)) 
    {
        fprintf(stderr, "%s\n", mysql_error(con));
        mysql_close(con);
        exit(1);
    }

    // Get results
    MYSQL_RES *result = mysql_store_result(con);
    int num_fields = mysql_num_fields(result);

    MYSQL_ROW row;
    int postFound = 1;
   
   
    if (mysql_fetch_row(result) == NULL)
    {
        postFound = 0;
    }

    free(selectQuery);

    char* updateQuery;

    if (!postFound) { return postID; }

    // Build a query
    if (0 > asprintf(&updateQuery, "UPDATE blog_posts SET author_id=(%d) WHERE id=(%d)",
        authorID,
        postID
    )) exit(1);
   
    // Query the server, if successful continue, else throw error
    if (mysql_query(con, updateQuery)) 
    {
        fprintf(stderr, "%s\n", mysql_error(con));
        mysql_close(con);
        exit(1);
    }

    free(updateQuery);

    return postID;
}

// Toggles the posts state, which determines whether the code ignores it.
int TogglePost(int postID, MYSQL* con)
{
    if (con == NULL) 
    {
        con = conn2maria();
    }

    char* selectQuery;
    if(0 > asprintf(&selectQuery, 
        "SELECT * FROM blog_posts WHERE id=(%d)", 
        postID
    )) exit(1);

    // Query the server, if successful continue, else throw error
    if (mysql_query(con, selectQuery)) 
    {
        fprintf(stderr, "%s\n", mysql_error(con));
        mysql_close(con);
        exit(1);
    }

    // Get results
    MYSQL_RES *result = mysql_store_result(con);
    int num_fields = mysql_num_fields(result);

    MYSQL_ROW row;
    int postFound = 1;
   
    row = mysql_fetch_row(result);

    if (row == NULL)
    {
        return postID;
    }

    int state = atoi(row[5]);
    free(selectQuery);

    char* updateQuery;

    // Build a query
    if (0 > asprintf(&updateQuery, "UPDATE blog_posts SET state=(%d) WHERE id=(%d)",
        !state,
        postID
    )) exit(1);
   
    // Query the server, if successful continue, else throw error
    if (mysql_query(con, updateQuery)) 
    {
        fprintf(stderr, "%s\n", mysql_error(con));
        mysql_close(con);
        exit(1);
    }

    free(updateQuery);

    return postID;
}

// Return true if state is 0, false if it doesn't exist or 1
bool IsEnabled(int postID, MYSQL* con)
{
    if (con == NULL) 
    {
        con = conn2maria();
    }

    char* selectQuery;
    if(0 > asprintf(&selectQuery, 
        "SELECT * FROM blog_posts WHERE id=(%d)", 
        postID
    )) exit(1);

    // Query the server, if successful continue, else throw error
    if (mysql_query(con, selectQuery)) 
    {
        fprintf(stderr, "%s\n", mysql_error(con));
        mysql_close(con);
        exit(1);
    }

    // Get results
    MYSQL_RES *result = mysql_store_result(con);
    int num_fields = mysql_num_fields(result);

    MYSQL_ROW row;
    int postFound = 1;
   
    row = mysql_fetch_row(result);

    if (row == NULL)
    {
        return false;
    }

    int state = atoi(row[5]);
    free(selectQuery);
    return !state;
}

void *ActivePostIDs(MYSQL* con)
{


    if (con == NULL) 
    {
        con = conn2maria();
    }

    // Query the server, if successful continue, else throw error
    if (mysql_query(con, "SELECT COUNT(*) FROM blog_posts WHERE state=(0)"))
    {
        fprintf(stderr, "%s\n", mysql_error(con));
        mysql_close(con);
        exit(1);
    }

    // Get results
    MYSQL_RES *result = mysql_store_result(con);
    int num_fields = mysql_num_fields(result);

    MYSQL_ROW row;
    int postFound = 1;
   
    row = mysql_fetch_row(result);

    int count = atoi(row[0]);

    printf("%d\n", count);

   
    // Query the server, if successful continue, else throw error
    if (mysql_query(con, "SELECT id FROM blog_posts WHERE state=(0)")) 
    {
        fprintf(stderr, "%s\n", mysql_error(con));
        mysql_close(con);
        exit(1);
    }

    free(result);

    MYSQL_RES *result2 = mysql_store_result(con);

    int *arr = (int *)realloc(arr, sizeof(int) * count);

    for (int i = 0; i < count; ++i) {
        row = mysql_fetch_row(result2);
        arr[i] = atoi(row[0]);
    }

    //return sizeof(int) * count;
    //return count;

    return arr;


}


// Main
int main(int argc, char *argv[])
{
    /*
    // =================================
    // Example of using 'PullPostData()'
    // =================================

    // Init array of six strings
    // Pull data of postID '1' into 'result'
    char *result[6]; 
    PullPostData(result, 1, NULL);

    // Foreach in result
    for (int i = 0; i < sizeof(result)/sizeof(result[0]); i++)
    {
        // Print contents on a new line
        printf("%s\n", result[i]);
    }

    // =================================
    */

    /*
    char *result[4];
    PullAuthorData(result, 1, NULL);

    // Foreach in result
    for (int i = 0; i < sizeof(result)/sizeof(result[0]); i++)
    {
        // Print contents on a new line
        printf("%s\n", result[i]);
    }
    */

    // Open the connection
    MYSQL *con = conn2maria();

    // =================================
    // Example of using 'PullPostData()'
    // =================================
    
    // AddPost return the inserted rows, NULL pointer for no tags, 0 for size
    
    //int tags[] = {1, 2, 3};
    //printf("%d", AddPost("Something", 1, "2020-01-01", "Ssdjshdjahdkjomething", tags, sizeof(tags)));
    //AssignTag(6, 42, con);
    //EditPost(69, "HEY", "THERE BUDDY", con);
    //printf("%d\n", AddTag("Test", con));
    //DeleteTag(7, con);
    //RetractTag(1, 1, con);
    //EditTag(5, "Projects", con);
    //AddAuthor("Me", "Meson", "email@me.com", con);
    //ChangeAuthor(62, 2, con);
    //TogglePost(51, con);
    //printf("%s\n", IsEnabled(51, con) ? "True" : "False");
    
    int *num;

    ActivePostIDs(con);



    // =================================

    exit(0);
}