#include <assert.h>
#include <getopt.h>
#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>
#include <unistd.h>

#include <ncurses.h>

#include "config.h"
#include "include/cache.h"
#include "include/draw.h"
#include "include/entry.h"
#include "include/group.h"
#include "include/read_cfg.h"
#define FLAG_COUNT 3
#define GAP_SIZE 1
#define MAX_LEN 6
#define WIDTH (getmaxx(stdscr)) //width of the entire term
#define HEIGHT (getmaxy(stdscr)) //height of the entire term

bool *handle_args(int argc, char **argv, char **cfg_path);
void print_help(char *exec_name);
void print_version();
void update_display(bool resize);
void draw_title();
void draw_win(WINDOW *new, char *title);
void fill_col(int mode); //0 = GROUP, 1 = ENTRY
char *trim_name(char *name, char *path, int max_len);
void update_col(int mode, int y_hl, bool resize); //mode: 0 = GROUP, 1 = ENTRY, 2 = INFO
void switch_col();
void trav_col(int new_i);
int locateChar(char input);

WINDOW *group_win = NULL;
WINDOW *entry_win = NULL;
WINDOW *info_win = NULL;
int g_hover = 0;
int *e_hover;
int true_hover = 0; //0 = hovering on groups, 1 = hovering on entries
GROUP **g;
int g_count;
int g_offset = 0;
int *e_offset;

int main(int argc, char **argv){
	bool *flags_set = NULL;
	char *cfg_path = malloc(sizeof(char) * BUF_LEN);
	int input;
	char full_command[BUF_LEN]; //what will be executed
	int prev_width;             //used to check if the window was resized
	int prev_height;            //used to check if the window was resized
	int i;

	srand(time(NULL));

	flags_set = handle_args(argc, argv, &cfg_path);
	//exit if args could not be interpreted (i.e., --config with no argument)
	if(flags_set == NULL) {                            
		print_help(argv[0]);
		return 1;                     
	}
	if(flags_set[1]) return(0);                         //exit if help flag was passed
	if(flags_set[2]) freopen("/dev/null", "w", stdout); //turn off output if quiet flag was passed
	if(flags_set[3]) return(0);                         // exit if version flag was passed
	if(!flags_set[0]) strcpy(cfg_path, find_config());  //find_config if not config flag was passed

	//Fill Groups
	//read the contents of the cfg file; print help message if invalid
	g = cfg_interp(cfg_path, &g_count);
	if(g == NULL) {
		print_help(argv[0]);
		return 1;
	}
	// DEBUG
	//for(i = 0; i < g_count; ++i) {
	//	group_debug(g[i]);
	//}
	//return 0;

	/*
	//Remove Empty Groups from the Array
	clean_groups();
	g = get_groups(); //retrieve results of cfg_interp
	g_count = get_gcount(); //retrieve number of groups in g (only do this after removing empty groups)
	*/

	//check that there are is at least one valid group
	if(g_count == 0){
		printf("Error: No Entries!\n");
		exit(0);
	}

	//initialize e_hover to track hover on each group
	e_hover = calloc(g_count, sizeof(int));
	e_offset = calloc(g_count, sizeof(int));

	//load cached data
	//load_cache(g_count, &g_hover, &e_hover, &e_offset, &true_hover, cfg_path);

	//reopen stdout for drawing menu
	freopen("/dev/tty", "w", stdout);

	initscr();
	cbreak();
	keypad(stdscr, true);
	noecho();
	set_escdelay(1); //used to avoid delay after ESC is pressed
	start_color();

	init_pair(0, COLOR_WHITE, COLOR_BLACK);
	init_pair(1, COLOR_BLACK, COLOR_WHITE);
	init_pair(2, COLOR_BLACK, COLOR_YELLOW);
	init_pair(3, COLOR_BLACK, COLOR_GREEN);
	attron(COLOR_PAIR(0));

	prev_width = WIDTH;
	prev_height = HEIGHT;

	//update to show menu
	update_display(false);

	//update highlighting for loaded location
	i = true_hover;
	true_hover = 0;
	trav_col(g_hover);
	switch_col();
	trav_col(e_hover[g_hover]);
	true_hover = i;
	update_display(true);

	//drawing is done, now run a while loop to receive input (ESC ends this loop)
	input = 0;
	while(input != 27){
		input = getch();

		switch(input){
			case 9: //tab key
			case KEY_LEFT:
			case KEY_RIGHT:
				//switch true_hover to look at the other column
				switch_col();
				break;

			case KEY_DOWN:
				trav_col((true_hover ? e_hover[g_hover] : g_hover)+1);
				break;

			case KEY_UP:
				trav_col((true_hover ? e_hover[g_hover] : g_hover)-1);
				break;

			case KEY_PPAGE:
			//case KEY_SUP:
				trav_col(0);
				break;

			case KEY_NPAGE:
			//case KEY_SDOWN:
				trav_col((true_hover ? get_ecount(g[g_hover]) : g_count)-1);
				break;

			case KEY_F(3):
			//jump to random group/entry
				trav_col(rand() % (true_hover ? get_ecount(g[g_hover]) : g_count));
				break;

			case KEY_F(5):
			//manual refresh (for debug purposes)
				update_display(true);
				break;

			case 10: //enter key
				//create a green highlight over the launched entry
				mvwchgat(entry_win, 1+e_hover[g_hover]-e_offset[g_hover], 1, getmaxx(entry_win)-2, A_DIM, 3, NULL);
				wrefresh(entry_win);

				launch();
				break;

			default: //a search char was entered, locate where to jump to
				trav_col(locateChar(input));
		}

		//redraw all windows if term is resized
		if(prev_width != WIDTH || prev_height != HEIGHT) update_display(true);

		//update prevs
		prev_width = WIDTH;
		prev_height = HEIGHT;
	}
	
	endwin();

	//save position data to cache
	save_to_cache(g_count, g_hover, e_hover, e_offset, true_hover, cfg_path);

	return 0;
}

bool *handle_args(int argc, char **argv, char **cfg_path){
	//create bool array with set flags
	// 0 -> -c|--config
	// 1 -> -h|--help
	// 2 -> -q|--quiet
	// 3 -> -v|--version

	int opt = 0;
	struct option long_options[] = {
		{"config",  required_argument, NULL, 'c'}, 
		{"help",    no_argument,       NULL, 'h'},
		{"quiet",   no_argument,       NULL, 'q'},
		{"version", no_argument,       NULL, 'v'},
		{0,         0,                 0,    0}
	};
	bool *flags_set = calloc(FLAG_COUNT+1, sizeof(bool));
	int i = 0;

	while(opt != -1){
		opt = getopt_long(argc, argv, "c:hqv", long_options, &i);
		switch(opt){
			case 0:
				printf("Unknown long option '%s'", long_options[i].name);
				if(optarg)
					printf(" with arg '%s'", optarg);
				printf("\n");
				break;
			case 'c':
				strcpy(*cfg_path, optarg);
				flags_set[0] = true;
				break;
			case 'h':
				print_help(argv[0]);
				flags_set[1] = true;
				opt = -1; // break out of the while loop
				break;
			case 'q':
				flags_set[2] = true;
				break;
			case 'v':
				print_version();
				flags_set[3] = true;
				opt = -1; // break out of the while loop
				break;
			case '?':
				return NULL; // error parsing arguments
			case -1:
				break; // don't print unknown option message if at the end of the list
			default:
				printf("Unknown short option: '%c'\n", opt);
		}
	}

	return flags_set;
}

void print_help(char *exec_name){
	printf("Usage: %s [OPTION]\n", exec_name);
	printf("Draw an Ncurses Menu to Launch Media from\n\n");

	printf(" -c, --config=FILE    Specify a configuration file path\n");
	printf(" -h, --help           Print this help message\n");
	printf(" -q, --quiet          Suppress stdout messages\n");
	printf(" -v, --version        Print version information and exit\n");
}

void print_version() {
	printf("%s\n", PACKAGE_STRING);
	printf("Copyright (C) Louie S.\n");
	printf("License GPLv3: GNU GPL version 3 <https://gnu.org/licenses/gpl.html>\n");
	printf("\n");
	printf("Written by Louie S.\n");
}

void update_display(bool resize){
	if(WIDTH < 20 || HEIGHT < 6){
		endwin();
		printf("Unable to draw: Terminal Window is Too Small\n");
		exit(0);
	}

	//title at the top (Terminal Media Launcher) (23 chars)
	draw_title();

	if(group_win != NULL) delwin(group_win);
	if(entry_win != NULL) delwin(entry_win);
	if(info_win != NULL) delwin(info_win);

	//Draw Columns 
	group_win = newwin(HEIGHT-(5+GAP_SIZE), WIDTH/2, 2+GAP_SIZE, 0);
	entry_win = newwin(HEIGHT-(5+GAP_SIZE), WIDTH-WIDTH/2, 2+GAP_SIZE, WIDTH/2);
	info_win = newwin(3, WIDTH, HEIGHT-3, 0);
	draw_win(group_win, "GROUP");
	draw_win(entry_win, "ENTRY");
	draw_win(info_win, "INFO");
	update_col(0, getmaxy(group_win)-2, resize);

	//start with hover on the first group, draw the entries from the selected group, true_hover is over the groups (rather than the entries) (do update after first draw, only after subsequent (resize) updates)
	if(resize){
		update_col(1, getmaxy(entry_win)-2, resize);
		update_col(2, 1, resize);
	}
	curs_set(0); //hide the cursor
	//move(3, (WIDTH/4)+10);
	refresh();
}

void draw_title(){
	WINDOW *title;

	title = newwin(2, WIDTH, 0, 0);
	refresh();
	attron(A_BOLD | A_UNDERLINE);
	move(0, (WIDTH-23)/2);
	printw("Terminal Media Launcher");
	attroff(A_BOLD | A_UNDERLINE);
	box(title, 0, 0);
	wrefresh(title);

	return;
}

void draw_win(WINDOW *new, char *title){
	int title_len = strlen(title);

	box(new, 0, 0);
	attron(A_UNDERLINE);
	wmove(new, 0, (getmaxx(new)-1 - title_len)/2);
	wprintw(new, "%s", title);
	attroff(A_UNDERLINE);
	wrefresh(new);

	return;
}

void fill_col(int mode){
	//mode 0 = group
	//mode 1 = entry

	int i;
	ENTRY **entries = get_gentries(g[g_hover]);
	WINDOW *col = (mode ? entry_win : group_win);
	int count = (mode ? get_ecount(g[g_hover]) : g_count);
	int offset = (mode ? e_offset[g_hover] : g_offset);
	int max_len = getmaxx(col)-2; //longest possible string length that can be displayed in the window
	int ycoord = 1;
	int max_y = HEIGHT-(6+GAP_SIZE);
	char *name;

	for(i = 0+offset; i < count; i++){
		if(ycoord >= max_y) break; //reached the bottom of the terminal window, stop drawing
		name = (mode ? get_ename(entries[i]) : get_gname(g[i]));

		//the name is too long, take the group to the trimming function
		if(strlen(name) > max_len) name = trim_name(name, (mode ? get_epath(entries[i]) : get_gname(g[i])), max_len);
		wmove(col, ycoord, 1);
		wprintw(col, "%s", name);
		ycoord++;
	}

	wrefresh(col);
	return;
}


char *trim_name(char *name, char *path, int max_len){
	char *relative;

	//group name and path are equivalent: special procedure
	if(!(strcmp(name, path))){
		//find relative path name
		relative = strrchr(name, sep);
		name = relative+1;
		if(strlen(name) <= max_len) return name;
	}

	name[max_len] = '\0';
	return name;
}

void update_col(int mode, int y_hl, bool resize){
	//mode 0 = group
	//mode 1 = entry
	//mode 2 = info

	WINDOW *col;
	char *name;
	int name_len;
	char *execution;

	switch(mode){
		case 0:
			col = group_win;
			name = "GROUP";
			name_len = 5;
			break;

		case 1:
			col = entry_win;
			name = "ENTRY";
			name_len = 5;
			break;

		case 2:
			col = info_win;
			name = "EXECUTION";
			name_len = 9;
			break;


		default:
			return;
	}

	//reset the column window (including reboxing and redrawing the title)
	wclear(col);
	box(col, 0, 0);
	wmove(col, 0, (getmaxx(col)-1 - name_len)/2);
	wprintw(col, "%s", name);
	wrefresh(col);

	//update certain info in the col only if not a resizing-related call
	switch(mode){
		case 0:
			fill_col(0);
			if(!resize) mvwchgat(group_win, y_hl, 1, getmaxx(group_win)-2, A_DIM, 2, NULL);
			else mvwchgat(group_win, 1+g_hover-g_offset, 1, getmaxx(group_win)-2, A_DIM, (true_hover ? 1 : 2), NULL);
			break;

		case 1:
			fill_col(1);
			if(!resize) mvwchgat(entry_win, y_hl, 1, getmaxx(entry_win)-2, A_DIM, 1, NULL);
			else mvwchgat(entry_win, 1+e_hover[g_hover]-e_offset[g_hover], 1, getmaxx(entry_win)-2, A_DIM, (true_hover ? 2 : 1), NULL);
			break;

		default:
			execution = get_launch();
			if(strlen(execution) >= getmaxx(info_win)-1){
				execution[getmaxx(info_win) - 2] = '\0';
				execution[getmaxx(info_win) - 3] = '.';
				execution[getmaxx(info_win) - 4] = '.';
				execution[getmaxx(info_win) - 5] = '.';
			}
			mvwprintw(info_win, 1, 1, "%s", execution);

	}

	wrefresh(col);
	return;
}

void switch_col(){
	true_hover = (true_hover+1) % 2;
	if(true_hover){
		mvwchgat(group_win, 1+g_hover-g_offset, 1, getmaxx(group_win)-2, A_DIM, 1, NULL); //adjust group light
		mvwchgat(entry_win, 1+e_hover[g_hover]-e_offset[g_hover], 1, getmaxx(entry_win)-2, A_DIM, 2, NULL); //adjust entry light
	}
	else{
		mvwchgat(group_win, 1+g_hover-g_offset, 1, getmaxx(group_win)-2, A_DIM, 2, NULL); //adjust group light
		mvwchgat(entry_win, 1+e_hover[g_hover]-e_offset[g_hover], 1, getmaxx(entry_win)-2, A_DIM, 1, NULL); //adjust entry light
	}
	move(3, (WIDTH/4)+10);

	wrefresh(group_win);
	wrefresh(entry_win);
	return;
}

void trav_col(int new_i){
	int *focus = (true_hover ? &(e_hover[g_hover]) : &g_hover); //make it easy to know which column we are looking at
	int *offset = (true_hover ? &(e_offset[g_hover]) : &g_offset);
	int count = (true_hover ? get_ecount(g[g_hover]) : g_count);
	int max_hl = HEIGHT-(3+GAP_SIZE); //for some reason, this works
	int min_hl = 5;
	int oob_flag = 0; //0 = none, 1 = bottom, 2 = top

	//check if the traversal is valid (i.e. not at top/bottom), alter if not
	if(new_i < 0) return;
	if(new_i >= count) new_i = count-1;

	//reset previously highlighted entry and group, change focus
	mvwchgat(entry_win, 1+e_hover[g_hover]-e_offset[g_hover], 1, getmaxx(entry_win)-2, A_NORMAL, 0, NULL);
	mvwchgat(group_win, 1+g_hover-g_offset, 1, getmaxx(group_win)-2, A_NORMAL, 0, NULL);
	*focus = new_i;

	//check offsets relating to new highlight, make sure highlight did not go oob
	while(*focus-*offset+5 > max_hl){
		(*offset)++;
		oob_flag = 1;
	}
	while(*focus-*offset+5 < min_hl){
		(*offset)--;
		oob_flag = 2;
	}

	if(oob_flag > 0){
		if(true_hover){
			update_col(1, (oob_flag == 1 ? getmaxy(entry_win)-2 : 1), false);
		}
		else{
			update_col(0, (oob_flag == 1 ? getmaxy(entry_win)-2 : 1), false);
		}
	}

	//highlight newly hovered upon entry/group
	mvwchgat(entry_win, 1+e_hover[g_hover]-e_offset[g_hover], 1, getmaxx(entry_win)-2, A_DIM, (true_hover ? 2 : 1), NULL);
	mvwchgat(group_win, 1+g_hover-g_offset, 1, getmaxx(group_win)-2, A_DIM, (true_hover ? 1 : 2), NULL);
	if(!true_hover){ //a little extra work regarding group hover
		update_col(1, e_hover[g_hover]+1, true);
	}

	wrefresh(group_win);
	wrefresh(entry_win);
	update_col(2, 1, false);
	return;
}

int locateChar(char input){
	ENTRY **entries = get_gentries(g[g_hover]);
	int location = (true_hover ? e_hover[g_hover] : g_hover);
	bool fold_case = true;
	char first_char;
	int i;

	if(fold_case && input >= 97 && input <= 122) input -= 32;

	if(true_hover){ //hovering on entries
		for(i = location+1; i < get_ecount(g[g_hover]); i++){
			first_char = get_ename(entries[i])[0];
			if(fold_case && first_char >= 97 && first_char <= 122) first_char -= 32;
			if(input == first_char){
				location = i;
				break;
			}
		}
	}

	else{ //hovering on groups
		for(i = location+1; i < g_count; i++){
			first_char = get_gname(g[i])[0];
			if(fold_case && first_char >= 97 && first_char <= 122) first_char -= 32;
			if(input == get_gname(g[i])[0]){
				location = i;
				break;
			}
		}
	}

	return location;
}

char *get_launch(){
	ENTRY **entries = get_gentries(g[g_hover]);
	char *program = get_gprog(g[g_hover]);
	char *flags = get_gflags(g[g_hover]);
	char *path = get_epath(entries[e_hover[g_hover]]);
	bool quotes = false;
	char *full_command = calloc(BUF_LEN, sizeof(char));

	//if the entry is an executable file (doesn't have a launcher)
	if(!(strcmp(program, "./"))){
		strcat(full_command, "\"");
		strcat(full_command, path);
		strcat(full_command, "\"");
	}

	else{
		if(quotes) strcat(full_command, "\"");
		strcat(full_command, program);
		if(quotes) strcat(full_command, "\"");
		if(flags[0] !='\0'){
			strcat(full_command, " ");
			strcat(full_command, flags);
		}
		strcat(full_command, " ");
		strcat(full_command, "\"");
		strcat(full_command, path);
		strcat(full_command, "\"");
	}

	return full_command;

}