#include "text.h"
#include "text.xpm"
/**
 * Word Processing Program
 * Features:
 *	-Real time editing
 *	-Saving
 *	-Loading	
 **/

int winx, winy;

int y_offset = 0; // TODO: move to local scope
int tab_offset = 0;
extern void convert_xpm(char **xpm, unsigned char **buffer);
extern unsigned char *QUINN_Icon;

WINDOW *menu;
WINDOW *editor;
WINDOW *linenos;

short curs_color(int fg)
{
    switch (7 & fg) {           /* RGB */
    case 0:                     /* 000 */
        return (COLOR_BLACK);
    case 1:                     /* 001 */
        return (COLOR_BLUE);
    case 2:                     /* 010 */
        return (COLOR_GREEN);
    case 3:                     /* 011 */
        return (COLOR_CYAN);
    case 4:                     /* 100 */
        return (COLOR_RED);
    case 5:                     /* 101 */
        return (COLOR_MAGENTA);
    case 6:                     /* 110 */
        return (COLOR_YELLOW);
    case 7:                     /* 111 */
        return (COLOR_WHITE);
    }
}

void init_colorpairs(void)
{
    int fg, bg;
    int colorpair;

    for (bg = 0; bg <= 7; bg++) {
        for (fg = 0; fg <= 7; fg++) {
            colorpair = colornum(fg, bg);
            init_pair(colorpair, curs_color(fg), curs_color(bg));
        }
    }
}



int colornum(int fg, int bg)
{
    int B, bbb, ffff;

    B = 1 << 7;
    bbb = (7 & bg) << 4;
    ffff = 7 & fg;

    return (B | bbb | ffff);
}


void setcolor(int fg, int bg)
{
    /* set the color pair (colornum) and bold/bright (A_BOLD) */

    attron(COLOR_PAIR(colornum(fg, bg)));
    if (is_bold(fg)) {
        attron(A_BOLD);
    }
}

void unsetcolor(int fg, int bg)
{
    /* unset the color pair (colornum) and
       bold/bright (A_BOLD) */

    attroff(COLOR_PAIR(colornum(fg, bg)));
    if (is_bold(fg)) {
        attroff(A_BOLD);
    }
}

int is_bold(int fg)
{
    /* return the intensity bit */

    int i;

    i = 1 << 3;
    return (i & fg);
}


void print_loc(int x, int y)
{
	int oldx, oldy;
	getyx(stdscr, oldy, oldx);
	wmove(menu, 0, COLS - 30);
	wprintw(menu, "X: %d Y: %d Offset: %d", x + 1, y + 1, y_offset);
	wclrtoeol(menu);
	move(oldy, oldx);
}

int main(int argc, char *argv[])
{	
	PAGE page;

	convert_xpm(text_xpm, &QUINN_Icon);

	if(argc > 1)
	{
        if(file_exists(argv[1]))
        {
		    load_file(&page, argv[1]);
        }
        else
        {
            init_page(&page, argv[1], PAGE_SIZE);
            page.numlines = 1;
        }
	}
	else // initialize
	{
		init_page(&page, "untitled.txt", PAGE_SIZE);
		page.numlines = 1;
	}
	
	/* curses interface */
	initscr();
	noecho();
	keypad(stdscr, 1);
	
	start_color();
    init_colorpairs();

	winx = 0;
	winy = 0;

    menu = subwin(stdscr, 2, 80, 23, 0);
	wbkgd(menu, COLOR_PAIR(colornum(COLOR_BLACK, COLOR_CYAN)));

	editor = subwin(stdscr, 23, 75, 0, 5);
	wbkgd(editor, COLOR_PAIR(colornum(COLOR_WHITE, COLOR_BLUE)));

    linenos = subwin(stdscr, 23, 5, 0, 0);
	wbkgd(linenos, COLOR_PAIR(colornum(COLOR_BLUE, COLOR_WHITE)));

	int beg = 0;
	int i;

	update_status(&page, "");
	
	print_page(editor, linenos, &page, beg);
	wmove(editor, winy, winx);
	while(1)
	{
        
		beg = y_offset;
		int ch = wgetch(editor);
		update_status(&page, ""); // default text
		switch(ch)
		{
			case KEY_F(4):
                if(prompt_yesno("Are you sure you want to quit?"))
				    goto endnc;
	            print_page(editor, linenos, &page, beg);
				break;
			case KEY_F(5):
				save_file(&page);
				update_status(&page, "Saved!");
				break;
            case KEY_F(6):
                prompt_string("Save As:", page.filename, NAME_LIMIT);
                save_file(&page);
				print_page(editor, linenos, &page, beg);
				update_status(&page, "Saved!");
                break;
			case KEY_UP:
				move_up(&page);
				break;
			case KEY_DOWN:
				move_down(&page);
				break;
			case KEY_LEFT:
				move_left(&page);
				break;
			case KEY_RIGHT:
				move_right(&page);
				break;
			case KEY_END:
				move_to_eol(&page);
			case KEY_DC:
			case 127: // backspace key...
			case KEY_BACKSPACE:
			case '\b':
				if(strlen(page.text[page.y].line) == 0)
				{	// can only delete blank lines for now
					remove_line(&page, page.y);
					move_up(&page);
				}
				else if( page.x > 0 )
				{
					remove_char(&page.text[page.y], page.x - 1); // delete
					move_left(&page);				  // char behind cursor
				}
				print_page(editor, linenos, &page, beg);
				wmove(editor, winy, winx);
				page.saved = 0;
				break;
            case '\t':
                for(i = 0; i < TAB_WIDTH; i++)
                {
                    insert_char(&page.text[page.y], ' ', page.x);
                    print_page(editor, linenos, &page, beg);
                    move_right(&page);
                }
				page.saved = 0;
                break;
			case '\n': // newline
				insert_line(&page, page.y + 1);
				print_page(editor, linenos, &page, beg);
				move_down(&page);
				break;
			default: // all other chars
				if( isprint(ch) )
				{
					insert_char(&page.text[page.y], ch, page.x);
					print_page(editor, linenos, &page, beg);
					move_right(&page);
					page.saved = 0;
				}
		}
		print_loc(page.x, page.y);
		wrefresh(menu);
		wrefresh(editor);
	}
endnc:	
	/* end curses */
    endwin();
	dest_page(&page);
	return EXIT_SUCCESS;
} // main

// prints a message at the bottom of the window
void update_status(PAGE *p, char *info)
{
	char title[61];

	snprintf(title, 60, "Text: %s%c", p->filename, p->saved == 1 ? ' ' : '*');

	PDC_set_title(title);
	wmove(menu, 0, 0); 
	wprintw(menu, "%s", info);
	wmove(menu, 1, 0); 
	wprintw(menu, "F4: Quit    F5: Save    F6: Save As ");
	wrefresh(menu);
} // update_status

/* movement */

void move_to_eol(PAGE *p)
{
	while (p->x <= strlen(p->text[p->y].line)) {
		move_right(p);
	}
}

void move_left(PAGE *p)
{
	if(p->x - 1 > 0) {
		p->x--;
		winx--;
		winy = 0;
		
		if (p->x > 75) {
			winx = p->x % 75;
			winy = p->x / 75;
		} else {
			winx = p->x;
		}

		for (int j = y_offset; j < p->y; j++) {
			winy += p->text[j].lines_in_screen;
		}

		wmove(editor, winy, winx);
	} else if (p->x - 1 == 0){
		p->x = 0;
		winx = 0;
	}
}


void move_right(PAGE *p)
{
	if(p->x <= strlen(p->text[p->y].line)) 
    {
		p->x++;
		winy = 0;

		if (p->x > 75) {
			winx = p->x % 75;
			winy = p->x / 75;
		} else {
			winx++;
		}

		for (int j = y_offset; j < p->y; j++) {
			if (strlen(p->text[j].line) > 75) {
				winy += p->text[j].lines_in_screen;
			} else {
				winy++;
			}
		}

		wmove(editor, winy, winx);
    }
}

void move_up(PAGE *p)
{
	if (p->y == y_offset && y_offset > 0) {
		p->y--;
		y_offset--;

		if( p->x > strlen(p->text[p->y].line) ) { // cursor adjusts
			p->x = strlen(p->text[p->y].line);  // to smaller lines
			int oldy = p->x / 75;
			p->x = strlen(p->text[p->y].line);
			winx = p->x % 75;
			winy = winy - (oldy - p->x / 75);
		}

		print_page(editor, linenos, p, y_offset);

		wmove(editor, winy, winx);
	} else if (p->y > 0) {
		p->y--;
		winy -= p->text[p->y].lines_in_screen;
		if( p->x > strlen(p->text[p->y].line) ) { // cursor adjusts
			int oldy = p->x / 75;
			p->x = strlen(p->text[p->y].line);
			winx = p->x % 75;
			winy = winy - (oldy - p->x / 75);
		}
		wmove(editor, winy, winx);
	}
}

void move_down(PAGE *p)
{
	if (p->y < p->numlines - 1) {
		winy += p->text[p->y].lines_in_screen;
		p->y++;
		int new_y_offset = y_offset;

		while (1) {
			int count = 0;
			for (int i = new_y_offset; i <= p->y; i++) {
				count += p->text[i].lines_in_screen;
			}
			if (count > EDITOR_SIZE) {
				new_y_offset++;
			} else {
				break;
			}
		}
		if (new_y_offset != y_offset) {
			winy = 0;
			for (int i = new_y_offset;i < p->y; i++) {
				winy += p->text[i].lines_in_screen;
			}
			y_offset = new_y_offset;
			print_page(editor, linenos, p, y_offset);	
		}
		if( p->x > strlen(p->text[p->y].line)) {
			int oldy = p->x / 75;
			p->x = strlen(p->text[p->y].line);
			winx = p->x % 75;
			winy = winy - (oldy - p->x / 75);
		}

		wmove(editor, winy, winx);
	}
}
/* movement */

int count_lines(FILE *fp)
{
	char ch = '\0';
	int count = 0;
	while((ch = fgetc(fp)) != EOF)
		if( ch == '\n' )
			count++;

    fseek(fp, 0, SEEK_SET); // go to beginning of file
	return count;
} // count_lines

/* saving and loading */
void load_file(PAGE *p, char *filename)
{
	FILE *fp = fopen(filename, "r");
	int size = count_lines(fp) * 2;
	char ch = '\0';
	int line;

    if(size < PAGE_SIZE)
        size = PAGE_SIZE;

	init_page(p, filename, size);

    if(fp == NULL) // file doesn't exist yet. don't bother reading
    {
        p->numlines = 1;
        return;
    }


    for(line = 0; line < size && ch != EOF; line++)
    {
        ch = fgetc(fp);
        while(ch != '\n' && ch != EOF)
        {
            LINE *currline = &(p->text[line]);
            if(ch != '\t')
            {
                add_char(currline, ch);
            }
            else // tab. add 4 spaces instead
            {
                int i;
                for(i = 0; i < TAB_WIDTH; i++)
                {
                    add_char(currline, ' ');
                }
            }
            ch = fgetc(fp);
        }
        p->numlines++;
    }

	fclose(fp);

} // load_file

void save_file(PAGE *p)
{
	FILE *fp = fopen(p->filename, "w");
	int line, col;

	for(line = 0; line < p->numlines; line++)
	{
		col = 0;
		while(p->text[line].line[col] != '\0')
		{
			fputc(p->text[line].line[col], fp);
			col++;
		}
		fputc('\n', fp);
	}

	fclose(fp);
	p->saved = 1;
} // save_file

int file_exists(char *filename)
{
    FILE *fp = fopen(filename, "r");
    if(fp != NULL) {
        fclose(fp);
        return 1;
    }
    return 0;
}
/* saving and loading */