/*
 * (C) Copyright 2014 Leo C. <erbl259-lmu@yahoo.de>
 *
 * (C) Copyright 2000-2003
 * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
 *
 * SPDX-License-Identifier:	GPL-2.0+
 */

/*
 * Misc boot support
 */
#include "common.h"
#include <stdlib.h>
#include <ctype.h>
#include <util/atomic.h>

#include "command.h"
#include "con-utils.h"
#include "z80-if.h"
#include "z180-serv.h"
#include "debug.h"

/* ugly hack to get Z180 loadfile into flash memory */
#define const const FLASH
#include "../z180/hdrom.h"
#undef const



static void z80_load_mem(void)
{
	unsigned sec = 0;
	uint32_t sec_base = hdrom_start;

	printf_P(PSTR("Loading Z180 memory... \n"));

	while (sec < hdrom_sections) {
		printf_P(PSTR("   From: 0x%.5lX to: 0x%.5lX    (%5li bytes)\n"),
				hdrom_address[sec],
				hdrom_address[sec]+hdrom_length_of_sections[sec] - 1,
				hdrom_length_of_sections[sec]);

		z80_bus_cmd(Request);
		z80_write_block_P((const FLASH unsigned char *) &hdrom[sec_base],  /* src */
				hdrom_address[sec],                  /* dest */
				hdrom_length_of_sections[sec]);      /* len */
		z80_bus_cmd(Release);
		sec_base+=hdrom_length_of_sections[sec];
		sec++;
	}
}

command_ret_t do_loadf(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
{
	(void) cmdtp; (void) flag; (void) argc; (void) argv;

	if (z80_bus_state() & ZST_RUNNING) {
		printf_P(PSTR("## Can't load while CPU is running!\n"));
		return CMD_RET_FAILURE;
	}

	z80_load_mem();

	return CMD_RET_SUCCESS;
}


command_ret_t do_busreq_pulse(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
{
	uint16_t count=1;

	(void) cmdtp; (void) flag;

	if (!(z80_bus_state() & ZST_RUNNING)) {
		printf_P(PSTR("## CPU is not running!\n"));
		return CMD_RET_FAILURE;
	}

	if (argc > 1)
		count = (uint16_t) strtoul(argv[2], NULL, 16);

	z80_bus_cmd(Request);
	while (count--)
		z80_bus_cmd(M_Cycle);

	return CMD_RET_SUCCESS;
}


command_ret_t do_go(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
{
	uint32_t addr;

	(void) cmdtp; (void) flag;

	if (argc < 2)
		return CMD_RET_USAGE;
	addr = strtoul(argv[1], NULL, 16);
	if (addr >= (1UL<<16)) {
		printf_P(PSTR("## Startaddress 0x%05lx too high.\n"
			"   (Out of logical address space (0x00000-0x0ffff))\n"),
			addr);
		return CMD_RET_FAILURE;
	}

	if (z80_bus_state() & ZST_RUNNING) {
		printf_P(PSTR("## CPU allready running!\n"));
		return CMD_RET_FAILURE;
	}

	printf_P(PSTR("## Starting application at 0x%04lx ...\n"), addr);

	if (addr != 0) {
		uint8_t tmp[3];
		uint_fast8_t i;

		z80_bus_cmd(Request);
		for (i = 0; i < 3; i++)
			tmp[i] = z80_read(i);
		z80_write(0, 0xc3);
		z80_write(1, addr);
		z80_write(2, (addr >> 8));

		z80_bus_cmd(Run);
		z80_bus_cmd(M_Cycle);
		z80_bus_cmd(M_Cycle);
		for (i = 0; i < 3; i++)
			z80_write(i, tmp[i]);
	} else
		z80_bus_cmd(Run);

	z80_bus_cmd(Release);

	return CMD_RET_SUCCESS;
}

static
void reset_cpu(bus_cmd_t mode)
{
	restart_z180_serv();
	z80_bus_cmd(mode);
}


command_ret_t do_reset(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
{
	(void) cmdtp; (void) flag; (void) argc; (void) argv;

	printf_P(PSTR("## CPU now in reset state.\n"));

	reset_cpu(Reset);
	return CMD_RET_SUCCESS;
}

command_ret_t do_restart(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
{
	(void) cmdtp; (void) flag; (void) argc; (void) argv;

	reset_cpu(Restart);

	return CMD_RET_SUCCESS;
}

static
void print_con_usage(char esc)
{	printf_P(PSTR("\n"
		"------------------------------------------------\n"
		" ?,H - This Help\n"
		" R   - Reset (Restart) CPU\n"
		" Q,X - Return to command line\n"
		" \\  - code input:\n"
		"      \\nnn   3 decimal digits character code\n"
		"      \\Xhh   2 hexadecimal digits character code\n"
		" ^%c - (Escape char) Type again to send itself\n"
		"key>"
	), esc + 0x40);
}

command_ret_t do_console(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
{
	int ch;
	uint8_t pending;
//	uint8_t help_prompt = 0;
	uint8_t code = 0;
	uint8_t state = 0;

	(void) cmdtp; (void) flag; (void) argc; (void) argv;


	while (1) {

		ATOMIC_BLOCK(ATOMIC_FORCEON) {
			pending = (Stat & S_CON_PENDING) != 0;
			Stat &= ~S_CON_PENDING;
		}
		if (pending) {
			uint8_t count = 100;
			while ((ch = z80_memfifo_getc(fifo_conout)) >= 0 && --count)
				putchar(ch);
		}

		if ((ch = my_getchar(0)) >= 0) {
			switch (state) {
			case 0:
				if (ch == CONFIG_ESC_CHAR) {
					state = 1;
					/* TODO: Timer starten */
				} else {
					z80_memfifo_putc(fifo_conin, ch);
				}
				break;
			case 2:
				printf_P(PSTR("\n"
				  "------------------------------------------------\n"));
			case 1:
				state = 0;
				switch (toupper(ch)) {

				case '?':
				case 'H':
					print_con_usage(CONFIG_ESC_CHAR);
					state = 2;
					break;

				case 'R':
					reset_cpu(Restart);
					break;

				case 'X':
				case 'Q':
					printf_P(PSTR("\n"));
					goto quit;
					break;

				case '\\':
					code = 0;
					state = 3;
					break;

				case CONFIG_ESC_CHAR:
					z80_memfifo_putc(fifo_conin, ch);
					break;
				default:
					break;
				}
				break;
			case 3:
				if (toupper(ch) == 'X') {
					state = 6;
					break;
				}
				/* fall thru */
			case 4:
			case 5:
				if (isdigit(ch)) {
					code = code * 10 + ch - '0';
					state++;
				}
				if (state > 5) {
					z80_memfifo_putc(fifo_conin, code);
					state = 0;
				}
				break;
			case 6:
			case 7:
				if (isxdigit(ch)) {
					ch = toupper(ch);
					if (ch >= 'A')
						ch -= 'A' - 10;
					code = code * 16 + ch - '0';
					state++;
				}
				if (state > 7) {
					z80_memfifo_putc(fifo_conin, code);
					state = 0;
				}
				break;
			}
		}
	}
quit:
	return CMD_RET_SUCCESS;
}