#include <stdio.h>
#include <stdlib.h>
#include "sqlite3.h"
#include "x_string.h"
#include "x_curses.h"
#include "dodo.h"


// FOR DEBUG
int callback(void *NotUsed, int argc, char **argv, char **azColName){
	int i;
	for(i=0; i<argc; i++){
		printf("%s = %s\n", azColName[i], argv[i] ? argv[i] : "NULL");
	}
	printf("\n");
	return 0;
}

// FOR DEBUG
int view_all(sqlite3 *db){
	int rc = 0;
	char* errmsg;

	//rc = sqlite3_exec(db, "SELECT * FROM all_info;", print_select, 0, &errmsg);
	rc = sqlite3_exec(db, "SELECT * FROM tasks;", callback, 0, &errmsg);
	//rc = sqlite3_exec(db, "SELECT * FROM entries;", print_select, 0, &errmsg);
	checksqlerr(rc, errmsg);
	return rc;
}

int gen_sql_update_stmt_v2(sqlite3 *db, sqlite3_stmt** out_stmt, char* table, char* new_title, char* new_due_date, char* new_project_tag, char* title_or_active_id){
	char sql_query[SQLQUERY_MAX];
	int rc = 0;

	if (new_title[0] != '\0' && new_due_date[0] != '\0'){
		//snprintf(sql_query, SQLQUERY_MAX, "UPDATE %s SET title='%s', due_date='%s', project_tag='%s' WHERE title='%s' OR active_id='%s'", table, status, title_or_active_id, title_or_active_id);
		snprintf(sql_query, SQLQUERY_MAX, "UPDATE %s SET title='%s', due_date='%s' WHERE title='%s' OR active_id='%s'", table, new_title, new_due_date, title_or_active_id, title_or_active_id);
	}
	else if (new_title[0] != '\0'){
		snprintf(sql_query, SQLQUERY_MAX, "UPDATE %s SET title='%s' WHERE title='%s' OR active_id='%s'", table, new_title, title_or_active_id, title_or_active_id);
	}
	else{
		return -1;
	}

	rc = sqlite3_prepare_v2(db, sql_query, -1, out_stmt, NULL);
	if (checksqlerr(rc, "prepare broken in gen_sql_insert_stmt")){
		return -1;
	}

	return 0;

}

// sql generators TODO: might be able to boil this down to 1 func
int gen_sql_update_stmt(sqlite3 *db, sqlite3_stmt** out_stmt, char* table, char* status, char* title_or_active_id){
	char sql_query[SQLQUERY_MAX];
	int rc = 0;

	if (status != NULL){
		snprintf(sql_query, SQLQUERY_MAX, "UPDATE %s SET status='%s' WHERE title='%s' OR active_id='%s'", table, status, title_or_active_id, title_or_active_id);
	}
	else{
		snprintf(sql_query, SQLQUERY_MAX, "UPDATE %s SET active_id='NULL',status='complete' WHERE title='%s' OR active_id='%s'", table, title_or_active_id, title_or_active_id);
	}

	rc = sqlite3_prepare_v2(db, sql_query, -1, out_stmt, NULL);
	if (checksqlerr(rc, "prepare broken in gen_sql_insert_stmt")){
		return -1;
	}

	return 0;

}

int gen_sql_delete_stmt(sqlite3 *db, sqlite3_stmt** out_stmt, char* table, char* title_or_active_id){
	char sql_query[SQLQUERY_MAX];
	int rc = 0;

	snprintf(sql_query, SQLQUERY_MAX, "DELETE FROM %s WHERE title='%s' OR active_id='%s'", table, title_or_active_id, title_or_active_id);

	rc = sqlite3_prepare_v2(db, sql_query, -1, out_stmt, NULL);
	if (checksqlerr(rc, "prepare broken in gen_sql_insert_stmt")){
		return -1;
	}

	return 0;
}

int gen_sql_insert_stmt(sqlite3 *db, sqlite3_stmt** out_stmt, char* table, char* colnames, char* values){
	char sql_query[SQLQUERY_MAX];
	int rc = 0;

	snprintf(sql_query, SQLQUERY_MAX, "INSERT INTO %s %s VALUES %s", table, colnames, values);
	rc = sqlite3_prepare_v2(db, sql_query, -1, out_stmt, NULL);
	if (checksqlerr(rc, "prepare broken in gen_sql_insert_stmt")){
		return -1;
	}

	return 0;
}

// Generate the sql statement by giving the columns, table, and current task list wanted
int gen_sql_select_stmt(sqlite3 *db, sqlite3_stmt** out_stmt, filtered_tasks* task){
	char sql_query[SQLQUERY_MAX];
	int rc = 0;

	snprintf(sql_query, SQLQUERY_MAX, "SELECT %s FROM %s WHERE status='%s' AND active_id!='NULL' ORDER BY due_date NULLS LAST", task->selected_columns, task->table, task->status);
	rc = sqlite3_prepare_v2(db, sql_query, -1, out_stmt, NULL);
	if (checksqlerr(rc, "prepare broken in gen_sql_select_stmt")){
		return -1;
	}

	return 0;
}

int checksqlerr(int rc, char *errmsg){
	if( rc!=SQLITE_OK ){
		fprintf(stderr, "rc =  %d\n", rc);
		fprintf(stderr, "SQL error: %s\n", errmsg);
		//sqlite3_free(errmsg);
		return -1;
	}
	return 0;
}

int opendb(sqlite3 **db, char* filename){
	int rc = 0;

	rc = sqlite3_open(filename, db);

	if ( rc != 0 ){
		fprintf(stderr, "Can't open database: %s\n", sqlite3_errmsg(*db));
		sqlite3_close(*db);
		return(rc);
	}

	return(rc);
}

void display_task_list_heading(char* heading){
	int width = (FIXED_ID_WIDTH + FIXED_TITLE_WIDTH + FIXED_DATE_WIDTH + x_strlen(heading) );
	int width_div_2 = width / 2;
	printf("%s%*s", X_BOLD, width_div_2, heading);
	printf("%*s", width_div_2 - x_strlen(heading), "");
	printf(" ");
}

void display_column_heading(const char* str){
	int width = 0;

	if ( x_strcmp(str, "id") == 0 ){
		width = FIXED_ID_WIDTH;
	}
	else if ( x_strcmp(str, "title") == 0 ){
		width = FIXED_TITLE_WIDTH;
	}
	else if ( x_strcmp(str, "due_date") == 0 ){
		width = FIXED_DATE_WIDTH;
	}
	else{
		width = FIXED_MAX_WIDTH;
	}

	printf("%s%s%-*.*s%s", X_BOLD, X_UNDL, width, width, str, X_RST);
}

void display_column_headings_for_all_task_lists(){
	int i = 0;
	char* str;
	for ( i = 0; i < NUM_TASK_LISTS; i++){
		str = "id";
		display_column_heading(str);
		str = "title";
		display_column_heading(str);
		str = "due_date";
		display_column_heading(str);
		printf(" ");
	}
	printf("\n");
}

// Print Heading 
void display_heading(){
	char * str;

	printf("\n");
	str = "Today";
	display_task_list_heading(str);
	str = "Backlog";
	display_task_list_heading(str);
	str = "Blocked";
	display_task_list_heading(str);
	printf("\n");

	display_column_headings_for_all_task_lists();
}

// pass in the args and return the title and due date
// due date passed as NULL if for delete
// TODO input validation for strings implement in strings!
// TODO maybe a Abstract Sytnax Tree for parsing
int parse_args(int argc, char** argv, filtered_tasks* task){

	if ( argc > 2 ){
		x_strcpy(task->title, argv[2], ARG_MAX);
	}

	if ( argc > 3 ){
		if ( x_strcmp(argv[1], "update") ){
			x_strcpy(task->due_date, argv[3], ARG_MAX);
			return 0;
		}
		else{
			x_strcpy(task->new_title, argv[3], ARG_MAX);
		}
	}

	if ( argc > 4 ){
		x_strcpy(task->due_date, argv[4], ARG_MAX);
	}

	if ( argc > 5 ){
		x_strcpy(task->project_tag, argv[5], ARG_MAX);
	}

	return 0;
}

// Get number of tasks from tasks table give status
int get_num_rows(sqlite3 *db, char* table, char* status){
	filtered_tasks* task = malloc(sizeof(filtered_tasks));
	x_strcpy(task->table, table, ARG_MAX);
	x_strcpy(task->status, status, ARG_MAX);
	x_strcpy(task->selected_columns, "COUNT(*)", ARG_MAX);
	sqlite3_stmt *out_stmt;
	int rc = 0;

	if ( gen_sql_select_stmt(db, &out_stmt, task) == 1 ){
		return -1;
	}

	free(task);

	while ( rc = sqlite3_step(out_stmt) == SQLITE_ROW ){
		return sqlite3_column_int(out_stmt, 0);
	}

	return rc;
}

// Print with FIXED_WIDTH
int print_fixed_width(const unsigned char* str, int width){
	if (str){
		printf("%-*.*s", width, width - FIXED_WHITESPACE, str);
	}else{
		printf("%-*.*s", width, width, "");
	}
}


int display_task_list(int start_col, sqlite3 *db, filtered_tasks* task){
	static int max_rows = -1;
	int rc = 0;
	int i = 0;
	int num_rows = -1;
	int num_cols = 0;
	int fixed_width = 0;
	char* errmsg;
	const unsigned char* col_val;
	const unsigned char* col_name;
	sqlite3_stmt* out_stmt;


	// Get the number of rows in current task list
	num_rows = get_num_rows(db, task->table, task->status);
	// Then keep track of the furthest down we go
	if (num_rows > max_rows){
		max_rows = num_rows;
	}

	// Generate the sql statement by giving the columns, table, and current task list wanted
	if ( gen_sql_select_stmt(db, &out_stmt, task) ){
		return -1;
	}

	// TODO: prob should be a func begin
	// Start col for the current task list
	X_goright(start_col);

	// while there is still rows available
	while ( rc = sqlite3_step(out_stmt) == SQLITE_ROW ){
		// for each column print the column
		num_cols = sqlite3_column_count(out_stmt); 
		for (i = 0; i < num_cols; i++){
			col_val = sqlite3_column_text(out_stmt, i);
			col_name = sqlite3_column_name(out_stmt, i);
			if ( x_strcmp(col_name, "title") == 0 ){
				fixed_width = FIXED_TITLE_WIDTH;
			}
			else if ( x_strcmp(col_name, "active_id") == 0 ){
				fixed_width = FIXED_ID_WIDTH;
			}
			else if ( x_strcmp(col_name, "due_date") == 0 ){
				fixed_width = FIXED_DATE_WIDTH;
			}
			print_fixed_width(col_val, fixed_width);
		}
		// move down one and over to the start of the current task column
		printf("\n");
	// end
		X_goright(start_col);
	}

	// if while loop broke and rc returned an error
	if ( rc == SQLITE_ERROR ){
		X_godown(max_rows);
		checksqlerr(rc, "step broken in display_task_list");
		return -1;
	}

	// Once the task list is completely printed
	// reset to the top of the task lists
	if (num_rows > 0){
		X_goup(num_rows);
	}

	// if it is the last task list move down one past the longest list
	if ( x_strcmp(task->status, "blocked") == 0){
		X_godown(max_rows);
		printf("\n");
	}
	return 0;
}

// Print kanban table
// All lists with task name and due date
int view_tasks(sqlite3 *db){

	// Set the table and cols to be printed
	filtered_tasks* tasks = malloc(sizeof(filtered_tasks));
	// TODO check that malloc is ok
	x_strcpy(tasks->table, "tasks", ARG_MAX);
	x_strcpy(tasks->selected_columns, "active_id, title, due_date", ARG_MAX);
	
	// Print Heading
	display_heading();

	// Print "today" tasks
	x_strcpy(tasks->status, "today", ARG_MAX);
	if ( display_task_list(TODAY_COL_START, db, tasks) ){
		free(tasks);
		return -1;
	}

	// Print "backlog" tasks
	x_strcpy(tasks->status, "backlog", ARG_MAX);
	if ( display_task_list(BACKLOG_COL_START, db, tasks) ){
		free(tasks);
		return -1;
	}

	// Print "blocked" tasks
	x_strcpy(tasks->status, "blocked", ARG_MAX);
	if ( display_task_list(BLOCKED_COL_START, db, tasks) ){
		free(tasks);
		return -1;
	}

	free(tasks);
	return 0;
}

// TODO: the way this ensures that we are only passing in
//       valid inputs is stupid and ugly FIX
int add_new_task(sqlite3 *db, int argc, char** argv){

	int rc = 0;
	char values[ARG_MAX];
	sqlite3_stmt* out_stmt;

	filtered_tasks* task = malloc(sizeof(filtered_tasks));
	x_strcpy(task->table, "tasks", ARG_MAX);
	task->title[0] = '\0';
	task->due_date[0] = '\0';

	parse_args(argc, argv, task);

	if ( task->title[0] != '\0' ){
		if ( task->due_date[0] != '\0' ){
			x_strcpy(task->selected_columns, "(title, due_date)", ARG_MAX);
			snprintf(values, 100, "('%s', '%s')", task->title, task->due_date);
		}else{
			x_strcpy(task->selected_columns, "(title)", ARG_MAX);
			snprintf(values, 100, "('%s')", task->title);
		}
	}

	if ( gen_sql_insert_stmt(db, &out_stmt, task->table, task->selected_columns, values) ){
		return -1;
	}
	if ( ( rc = sqlite3_step(out_stmt) ) == SQLITE_DONE){
		return 0;
	}

	checksqlerr(rc, "broken in add_new_task");
	return -1;
}


int update_task_status(sqlite3 *db, int argc, char** argv){
	int rc = 0;
	sqlite3_stmt* out_stmt;
	filtered_tasks* task = malloc(sizeof(filtered_tasks));

	x_strcpy(task->table, "tasks", ARG_MAX);

	// TODO: this is not just title but also active ID so fix this
	parse_args(argc, argv, task);

	if ( gen_sql_update_stmt(db, &out_stmt, task->table, argv[1], task->title) ){
		free(task);
		return -1;
	}

	if ( ( rc = sqlite3_step(out_stmt) ) == SQLITE_DONE){
		free(task);
		return 0;
	}

	checksqlerr(rc, "broken in update_task_status");

	free(task);
	return -1;

}


int complete_task(sqlite3 *db, int argc, char** argv){
	int rc = 0;
	sqlite3_stmt* out_stmt;
	filtered_tasks* task = malloc(sizeof(filtered_tasks));

	x_strcpy(task->table, "tasks", ARG_MAX);

	parse_args(argc, argv, task);
	if ( gen_sql_update_stmt(db, &out_stmt, task->table, NULL, task->title) ){
		free(task);
		return -1;
	}
	

	if ( ( rc = sqlite3_step(out_stmt) ) == SQLITE_DONE){
		free(task);
		return 0;
	}

	checksqlerr(rc, "broken in complete_task");

	free(task);
	return -1;
}

// TODO this can definatly be made into one func with all the other updates
int update_task(sqlite3 *db, int argc, char** argv){
	int rc = 0;
	sqlite3_stmt* out_stmt;
	filtered_tasks* task = malloc(sizeof(filtered_tasks));
	
	task->new_title[0] = '\0';
	task->due_date[0] = '\0';
	x_strcpy(task->table, "tasks", ARG_MAX);

	parse_args(argc, argv, task);
	if ( gen_sql_update_stmt_v2(db, &out_stmt, task->table, task->new_title, task->due_date, task->project_tag, task->title) ){
		free(task);
		return -1;
	}

	if ( ( rc = sqlite3_step(out_stmt) ) == SQLITE_DONE){
		free(task);
		return 0;
	}

	checksqlerr(rc, "broken in complete_task");

	free(task);
	return -1;
}


int del_task(sqlite3 *db, int argc, char** argv){
	int rc = 0;
	sqlite3_stmt* out_stmt;
	filtered_tasks* task = malloc(sizeof(filtered_tasks));

	x_strcpy(task->table, "tasks", ARG_MAX);

	parse_args(argc, argv, task);
	if ( gen_sql_delete_stmt(db, &out_stmt, task->table, task->title) ){
		free(task);
		return -1;
	}

	if ( ( rc = sqlite3_step(out_stmt) ) == SQLITE_DONE){
		free(task);
		return 0;
	}

	checksqlerr(rc, "broken in del_task");

	free(task);
	return -1;
}