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

#define WIDTH 38
#define HEIGHT 23
#define V4L "/usr/bin/v4l2-ctl -c %s=%d"
#define SAVEFILE "/boot/camera.txt"
#define DEBUG false

typedef struct {
	char name[30]; // Internal Control Name
	char display[25]; // Friendly Control Name
	int min; // Minimum Control Value
	int max; // Maximum Control Value
	int init; // Default Control Value
	int value; // Current Control Value
	bool hasoptions; // Enables Options
	char options[20][20]; // Option Array
} control;

control controls[] = {
	{"brightness", "Brightness", 0, 100, 50, 50},
	{"contrast", "Contrast", -100, 100, 0, 0},
	{"saturation", "Saturation", -100, 100, 0, 0},
	{"red_balance", "Red", 1, 7999, 1000, 1000},
	{"blue_balance", "Blue", 1, 7999, 1000, 1000},
	{"horizontal_flip", "Horizontal Flip", 0, 1, 0, 0},
	{"vertical_flip", "Vertical Flip", 0, 1, 0, 0},
	{"power_line_frequency", "Powerline Frequency", 0, 3, 1, 1, true, {"Off ","50Hz","60Hz","Auto"}},
	{"sharpness", "Sharpness", -100, 100, 0, 0},
	{"color_effects", "Colour Effects", 0, 15, 0, 0, true, {"None         ","Black & White","Sepia        ","Negative     ","Emboss       ","Sketch       ","Sky Blue     ","Grass Green  ","Skin Whiten  ","Vivid        ","Aqua         ","Art Freeze   ","Silhouette   ","Solarization ","Antique      ","Set Cb/Cr    "}},
	{"rotate", "Rotate", 0, 3, 0, 0, true, {"0  ","90 ","180","270"}},
	{"color_effects_cbcr", "Chroma", 0, 65535, 32896, 32896},
	{"auto_exposure", "Manual Exposure", 0, 1, 0, 0},
	{"exposure_time_absolute", "Exposure Time", 1, 10000, 1000, 1000},
	{"exposure_dynamic_framerate", "Dynamic Framerate", 0, 1, 0, 0},
	{"auto_exposure_bias", "Auto Exposure Bias", 0, 24, 12, 12},
	{"white_balance_auto_preset", "White Balance Preset", 0, 10, 1, 1, true, {"Manual       ","Auto         ","Incandescent ","Fluorescent  ","Fluorescent H","Horizon      ","Daylight     ","Flash        ","Cloudy       ","Shade        ","Greyworld    "}},
	{"image_stabilization","Image Stabilisation", 0, 1, 0, 0},
	{"iso_sensitivity", "ISO Sensitivity", 0, 4, 0, 0},
	{"iso_sensitivity_auto", "ISO Auto", 0, 1, 1, 1},
	{"exposure_metering_mode", "Exposure Metering", 0, 2, 0, 0, true, {"Average        ", "Center Weighted", "Spot           "}},
};

int n_controls = sizeof(controls) / sizeof(control);
void apply(int highlight);
void apply_all();
void reset();
void print_menu(WINDOW *menu_win, int highlight);
void menu_item(WINDOW *menu_win, int i, int y, int x);
void load();
void save();

int main()
{	WINDOW *menu_win;
	int highlight = 0;
	int increment = 0;
	bool quit = false;
	int c;

	initscr();
	clear();
	noecho();
	cbreak();
	
	menu_win = newwin(HEIGHT, WIDTH, 0, 0);
	keypad(menu_win, TRUE);
	mvprintw(1, WIDTH+1, "Up/Down Navigate");
	mvprintw(2, WIDTH+1, "Left/Right Adjust");
	mvprintw(3, WIDTH+1, "PgDn/PgUp Jump Adjust");
	mvprintw(4, WIDTH+1, "Enter Apply");
	
	mvprintw(6, WIDTH+1, "A Apply All");
	mvprintw(7, WIDTH+1, "R Reset All");
	mvprintw(8, WIDTH+1, "D Default");
	mvprintw(9, WIDTH+1, "N Minimum");
	mvprintw(10, WIDTH+1, "M Maximum");
	mvprintw(11, WIDTH+1, "L Load");
	mvprintw(12, WIDTH+1, "S Save");
	mvprintw(13, WIDTH+1, "Q Quit");
	refresh();
	print_menu(menu_win, highlight);
	while(!quit)
	{
		c = wgetch(menu_win);
		mvprintw(24, 0, "%*s", 80, " "); // Clear Status Bar
		refresh();
		
		switch(c)
		{	case KEY_UP:
				if(highlight <= 0)
					highlight = n_controls-1;
				else
					highlight--;
				break;
			case KEY_DOWN:
				if(highlight >= n_controls-1)
					highlight = 0;
				else 
					highlight++;
				break;
			case KEY_LEFT:
				if (controls[highlight].value > controls[highlight].min) controls[highlight].value--;
				break;
			case KEY_RIGHT:
				if (controls[highlight].value < controls[highlight].max) controls[highlight].value++;
				break;
			case 338: // Page Down
				increment = (int)(controls[highlight].max - controls[highlight].min)/10;
				if (controls[highlight].value-increment >= controls[highlight].min)
				{
					controls[highlight].value-=increment;
				}
				else
				{
					controls[highlight].value = controls[highlight].min;
				}
				break;
			case 339: // Page Up
				increment = (int)(controls[highlight].max - controls[highlight].min)/10;
				if (controls[highlight].value+increment <= controls[highlight].max)
				{
					controls[highlight].value+=increment;
				}
				else
				{
					controls[highlight].value = controls[highlight].max;
				}
				break;
			case 'N':
			case 'n':
				controls[highlight].value = controls[highlight].min;
				break;
			case 'M':
			case 'm':
				controls[highlight].value = controls[highlight].max;
				break;
			case 'D':
			case 'd':
				controls[highlight].value = controls[highlight].init;
				break;
			case 'A':
			case 'a':
				apply_all();
				break;
			case 'R':
			case 'r':
				reset();
				break;
			case 10: // Enter
				apply(highlight);
				break;
			case 'L':
			case 'l':
				if (!DEBUG) load();
				break;
			case 'S':
			case 's':
				if (!DEBUG) save();
				break;
			case 'Q':
			case 'q':
				quit = true;
				break;
			default:
				if (DEBUG)
				{
					mvprintw(24, 0, "Character %3d '%c'", c, c);
					refresh();
				}
				break;
		}
		print_menu(menu_win, highlight);
	}	
	clrtoeol();
	refresh();
	endwin();
	return 0;
}

void apply(int highlight)
{
	int value=0;
	
	if (strcmp(controls[highlight].name, "rotate") == 0) // Handle Rotate Special Case
	{
		value = atoi(controls[highlight].options[controls[highlight].value]);
	}
	else
	{
		value = controls[highlight].value;
	}
	
	if (DEBUG)
	{
		mvprintw(24, 0, V4L, controls[highlight].name, value);
	}
	else
	{
		char cmd[100];
		sprintf(cmd, V4L, controls[highlight].name, value);
		system(cmd);
	}
	
	refresh();
}

void reset()
{
	for (int i = 0; i < n_controls; i++)
	{
		controls[i].value = controls[i].init;
	}
}

void apply_all()
{
	for (int i = 0; i < n_controls; i++)
	{
		apply(i);
	}
}

void load()
{
	FILE *fp = fopen(SAVEFILE, "r");
	char name[30];
	int value;
	
	if (fp != NULL)
	{
	    while (fscanf(fp,"%[^=]=%d\r\n", name, &value) == 2) // Assume control=value file format
		{
			for (int i = 0; i < n_controls; i++)
			{
				if (strcmp(name, controls[i].name) == 0)
				{
					if (strcmp(name, "rotate") == 0) value = (int)value/90;
					controls[i].value = value;
					break;
				}
			}
		}
		refresh();
		fclose(fp);
	}
	else
	{
		mvprintw(24, 0, "Cannot load %s", SAVEFILE);
		refresh();
	}
}

void save()
{
	FILE *fp = fopen(SAVEFILE, "w"); // Overwrite existing file
	if (fp != NULL)
	{
		for (int i = 0; i < n_controls; i++)
		{
			int value=0;
			
			if (controls[i].value != controls[i].init)
			{
				if (strcmp(controls[i].name, "rotate") == 0)
				{
					value = atoi(controls[i].options[controls[i].value]);
				}
				else
				{
					value = controls[i].value;
				}
				
				fprintf(fp, "%s=%d\r\n", controls[i].name, value);
			}
		}
		fclose(fp);
	}
	else
	{
		mvprintw(24, 0, "Cannot save %s", SAVEFILE);
		refresh();
	}
}

void print_menu(WINDOW *menu_win, int highlight)
{
	int x, y, i;	

	x = 2;
	y = 1;
	box(menu_win, 0, 0);
	for (i = 0; i < n_controls; i++)
	{	if (highlight == i)
		{
			wattron(menu_win, A_REVERSE);
			menu_item(menu_win, i, y, x);
			wattroff(menu_win, A_REVERSE);
		}
		else
			menu_item(menu_win, i, y, x);
		y++;
	}
	wrefresh(menu_win);
}

void menu_item(WINDOW *menu_win, int i, int y, int x)
{
	if (controls[i].hasoptions)
	{
		mvwprintw(menu_win, y, x, "%s %s", controls[i].display, controls[i].options[controls[i].value]);
	}
	else
	{
		mvwprintw(menu_win, y, x, "%s %5d", controls[i].display, controls[i].value);
	}
}