/*
 rotenc_test.c

 Copyright 2018 Doug Szumski <d.s.szumski@gmail.com>

 Based on i2ctest.c by:

 Copyright 2008-2011 Michel Pollet <buserror@gmail.com>

 This file is part of simavr.

 simavr is free software: you can redistribute it and/or modify
 it under the terms of the GNU General Public License as published by
 the Free Software Foundation, either version 3 of the License, or
 (at your option) any later version.

 simavr is distributed in the hope that it will be useful,
 but WITHOUT ANY WARRANTY; without even the implied warranty of
 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 GNU General Public License for more details.

 You should have received a copy of the GNU General Public License
 along with simavr.  If not, see <http://www.gnu.org/licenses/>.
 */

#include <stdlib.h>
#include <stdio.h>
#include <libgen.h>
#if __APPLE__
#include <GLUT/glut.h>
#else
#include <GL/glut.h>
#endif

#include <pthread.h>
#include <curses.h>

#include "sim_avr.h"
#include "sim_gdb.h"
#include "sim_elf.h"
#include "rotenc.h"
#include "avr_ioport.h"
#include "sim_vcd_file.h"

avr_t * avr = NULL;
avr_vcd_t vcd_file;
rotenc_t rotenc;

volatile int state = cpu_Running;
volatile unsigned char key_g;
uint8_t pin_state_g = 0b00010000;

float pixsize = 64;

/*
 * Called when the AVR changes any of the pins on port C. We use this to
 * hook up these pins to the virtual 'LED bar'.
 */
void
pin_changed_hook(struct avr_irq_t * irq, uint32_t value, void * param)
{
	pin_state_g = (pin_state_g & ~(1 << irq->irq)) | (value << irq->irq);
}

void
displayCB(void)
{
	glClear(GL_COLOR_BUFFER_BIT);
	glMatrixMode(GL_MODELVIEW);
	glLoadIdentity();

	float grid = pixsize;
	float size = grid * 0.8;
	glBegin(GL_QUADS);
	glColor3f(1, 0, 0);

	for (int di = 0; di < 8; di++) {
		char on = (pin_state_g & (1 << di)) != 0;
		if (on) {
			float x = (di) * grid;
			float y = 0;
			glVertex2f(x + size, y + size);
			glVertex2f(x, y + size);
			glVertex2f(x, y);
			glVertex2f(x + size, y);
		}
	}

	glEnd();
	glutSwapBuffers();
	glFlush();
}

void
keyCB(unsigned char key, int x, int y)
{
	if (key == 'q')
		exit(0);

	switch (key) {
		case 'q':
		case 0x1f: // escape
			exit(0);
			break;
		default:
			// Pass key to avr thread
			key_g = key;
			break;
	}
}

void
timerCB(int i)
{
	static uint8_t oldstate = 0b00010000;

	// Restart timer
	glutTimerFunc(1000 / 64, timerCB, 0);

	// Only update if the pin changed state
	if (oldstate != pin_state_g) {
		oldstate = pin_state_g;
		glutPostRedisplay();
	}
}

static void *
avr_run_thread(void * ignore)
{
	state = cpu_Running;

	while ((state != cpu_Done) && (state != cpu_Crashed)) {
		if (key_g != 0) {
			switch (key_g) {
				case 'j':
					rotenc_twist(&rotenc, ROTENC_CCW_CLICK);
					break;
				case 'k':
					rotenc_button_press(&rotenc);
					break;
				case 'l':
					rotenc_twist(&rotenc, ROTENC_CW_CLICK);
					break;
				default:
					// ignore
					break;
			}
			key_g = 0;
		}
		state = avr_run(avr);
	}
	return NULL ;
}

int
main(int argc, char *argv[])
{
	elf_firmware_t f = {{0}};
	const char * fname = "atmega32_rotenc_test.axf";

	printf(
		"ROTARY ENCODER LED bar demo (press q to quit):\n\n"
		"Press 'j' for CCW turn \n"
		"Press 'l' for CW turn \n"
		"Press 'k' for button click \n\n");

	printf("Firmware pathname is %s\n", fname);
	elf_read_firmware(fname, &f);

	printf("firmware %s f=%d mmcu=%s\n", fname, (int) f.frequency, f.mmcu);

	avr = avr_make_mcu_by_name(f.mmcu);
	if (!avr) {
		fprintf(stderr, "%s: AVR '%s' not known\n", argv[0], f.mmcu);
		exit(1);
	}
	avr_init(avr);
	avr_load_firmware(avr, &f);

	// Uncomment for debugging
	//avr->gdb_port = 1234;
	//avr->state = cpu_Stopped;
	//avr_gdb_init(avr);

	// Initialise rotary encoder
	rotenc_init(avr, &rotenc);
	rotenc.verbose = 1;

	// RE GPIO
	avr_connect_irq(
		rotenc.irq + IRQ_ROTENC_OUT_A_PIN,
		avr_io_getirq(avr, AVR_IOCTL_IOPORT_GETIRQ('A'), 0));

	// RE INT
	avr_connect_irq(
		rotenc.irq + IRQ_ROTENC_OUT_B_PIN,
		avr_io_getirq(avr, AVR_IOCTL_IOPORT_GETIRQ('D'), 2));

	// INT (button)
	// Pull up
	avr_raise_irq(rotenc.irq + IRQ_ROTENC_OUT_BUTTON_PIN, 1);
	avr_connect_irq(
		rotenc.irq + IRQ_ROTENC_OUT_BUTTON_PIN,
		avr_io_getirq(avr, AVR_IOCTL_IOPORT_GETIRQ('B'), 2));

	// VCD output
	avr_vcd_init(avr, "gtkwave_output.vcd", &vcd_file, 1000 /* usec */);
	avr_vcd_add_signal(
		&vcd_file,
		avr_io_getirq(avr, AVR_IOCTL_IOPORT_GETIRQ('D'), 2), 1,
		"INT0");
	avr_vcd_add_signal(&vcd_file, rotenc.irq + IRQ_ROTENC_OUT_A_PIN, 1, "A");
	avr_vcd_add_signal(&vcd_file, rotenc.irq + IRQ_ROTENC_OUT_B_PIN, 1, "B");
	avr_vcd_start(&vcd_file);

	// Connect all the pins on port C to our callback. This is the 'LED bar'.
	for (int i = 0; i < 8; i++) {
		avr_irq_register_notify(
			avr_io_getirq(avr, AVR_IOCTL_IOPORT_GETIRQ('C'), i),
			pin_changed_hook,
			NULL);
	}

	// Set the button in the 'up' state
	avr_raise_irq(rotenc.irq + IRQ_ROTENC_OUT_BUTTON_PIN, 1);

	// Start the encoder at phase 1
	avr_raise_irq(rotenc.irq + IRQ_ROTENC_OUT_A_PIN, 0);
	avr_raise_irq(rotenc.irq + IRQ_ROTENC_OUT_B_PIN, 0);

	/*
	 * OpenGL init, can be ignored
	 */
	glutInit(&argc, argv);

	glutInitDisplayMode(GLUT_RGB | GLUT_DOUBLE);
	glutInitWindowSize(8 * pixsize, 1 * pixsize);
	glutCreateWindow("Glut");

	// Set up projection matrix
	glMatrixMode(GL_PROJECTION);
	glLoadIdentity();
	glOrtho(0, 8 * pixsize, 0, 1 * pixsize, 0, 10);
	glScalef(1, -1, 1);
	glTranslatef(0, -1 * pixsize, 0);

	glutDisplayFunc(displayCB);
	glutKeyboardFunc(keyCB);
	glutTimerFunc(1000 / 24, timerCB, 0);

	pthread_t run;
	pthread_create(&run, NULL, avr_run_thread, NULL);

	glutMainLoop();

	printf("quit\n");
}