/* sbc_harness/main.c - Main entry point and event loop for sbc-harness
 *
 * Copyright (C) 2024-2025  Luke T. Shumaker <lukeshu@lukeshu.com>
 * SPDX-License-Identifier: AGPL-3.0-or-later
 */

/* libc */
#include <string.h> /* libc: for strlen() */

/* pico-sdk */
#include <pico/stdio_uart.h> /* pico-sdk:pico_stdio_uart: for stdio_uart_init() */
#include <hardware/flash.h>  /* pico-sdk:hardware_flash: for flash_get_unique_id() */

/* our OS */
#include <libcr/coroutine.h>
#include <libhw/generic/alarmclock.h> /* so we can set `bootclock` */
#include <libhw/rp2040_hwspi.h>
#include <libhw/rp2040_hwtimer.h>
#include <libhw/w5500.h>

/* our application libraries */
#include <libdhcp/client.h>
#include <libusb/usb_common.h>
#include <lib9p/srv.h>
#include <util9p/static.h>

/* our utility libraries */
#include <libmisc/hash.h>
#define LOG_NAME MAIN
#include <libmisc/log.h>

/* local headers */
#include "usb_keyboard.h"
#include "static.h"

/* configuration **************************************************************/

#include "config.h"

/* file tree ******************************************************************/

enum { PATH_BASE = __COUNTER__ };
#define PATH_COUNTER __COUNTER__ - PATH_BASE

#define STATIC_FILE(STRNAME, ...) UTIL9P_STATIC_FILE(PATH_COUNTER, STRNAME, __VA_ARGS__)
#define STATIC_DIR(STRNAME, ...)  UTIL9P_STATIC_DIR(PATH_COUNTER, STRNAME, __VA_ARGS__)

struct lib9p_srv_file root =
		STATIC_DIR("",
		           STATIC_DIR("Documentation",
		                      STATIC_FILE("YOUR_RIGHTS_AND_OBLIGATIONS.md",
		                                  .data_start = _binary_static_Documentation_YOUR_RIGHTS_AND_OBLIGATIONS_md_start,
		                                  .data_end   = _binary_static_Documentation_YOUR_RIGHTS_AND_OBLIGATIONS_md_end),
		                      STATIC_DIR("YOUR_RIGHTS_AND_OBLIGATIONS",
		                                 STATIC_FILE("agpl-3.0.txt",
		                                             .data_start = _binary_static_Documentation_YOUR_RIGHTS_AND_OBLIGATIONS_agpl_3_0_txt_start,
		                                             .data_end   = _binary_static_Documentation_YOUR_RIGHTS_AND_OBLIGATIONS_agpl_3_0_txt_end),
		                                 STATIC_FILE("pico-sdk.bsd3.txt",
		                                             .data_start = _binary_static_Documentation_YOUR_RIGHTS_AND_OBLIGATIONS_pico_sdk_bsd3_txt_start,
		                                             .data_end   = _binary_static_Documentation_YOUR_RIGHTS_AND_OBLIGATIONS_pico_sdk_bsd3_txt_end),
		                                 STATIC_FILE("printf.mit.txt",
		                                             .data_start = _binary_static_Documentation_YOUR_RIGHTS_AND_OBLIGATIONS_printf_mit_txt_start,
		                                             .data_end   = _binary_static_Documentation_YOUR_RIGHTS_AND_OBLIGATIONS_printf_mit_txt_end),
		                                 STATIC_FILE("tinyusb.mit.txt",
		                                             .data_start = _binary_static_Documentation_YOUR_RIGHTS_AND_OBLIGATIONS_tinyusb_mit_txt_start,
		                                             .data_end   = _binary_static_Documentation_YOUR_RIGHTS_AND_OBLIGATIONS_tinyusb_mit_txt_end),
		                                 STATIC_FILE("newlib.txt",
		                                             .data_start = _binary_static_Documentation_YOUR_RIGHTS_AND_OBLIGATIONS_newlib_txt_start,
		                                             .data_end   = _binary_static_Documentation_YOUR_RIGHTS_AND_OBLIGATIONS_newlib_txt_end),
		                                 ),
		                      STATIC_FILE("harness_rom_bin.txt",
		                                  .data_start = _binary_static_Documentation_harness_rom_bin_txt_start,
		                                  .data_end   = _binary_static_Documentation_harness_rom_bin_txt_end),
		                      STATIC_FILE("harness_flash_bin.txt",
		                                  .data_start = _binary_static_Documentation_harness_flash_bin_txt_start,
		                                  .data_end   = _binary_static_Documentation_harness_flash_bin_txt_end),
		                      ),
		           STATIC_DIR("harness",
		                      STATIC_FILE("rom.bin",
		                                  .data_start = (void*)0x00000000,
		                                  .data_size  = 16*1024),
		                      // TODO: Make flash.bin writable.
		                      STATIC_FILE("flash.bin",
		                                  .data_start = (void*)0x10000000,
		                                  .data_size  = PICO_FLASH_SIZE_BYTES),
		                      // TODO: system.log
		                      // TODO: proc.txt
		                      // TODO: cpuinfo.txt
		                      // TODO: ctl
		                      ),
		           STATIC_DIR("dut",
		                      // TODO: hdmi.nut
		                      // TODO: uart.txt
		                      // TODO: usb-keyboard.txt
		                      ),
		           );

static lo_interface lib9p_srv_file get_root(struct lib9p_srv_ctx *LM_UNUSED(ctx), struct lib9p_s LM_UNUSED(treename)) {
	return root;
}

/* Code ***********************************************************************/

/*
static COROUTINE hello_world_cr(void *_chan) {
	const char *msg = "Hello world!\n";
	usb_keyboard_rpc_t *chan = _chan;
	cr_begin();

	for (size_t i = 0;; i = (i+1) % strlen(msg)) {
		int result = usb_keyboard_rpc_send_req(chan, (uint32_t)msg[i]);
		if (result < 1) {
			errorf("error sending rune U+%d", (uint32_t)msg[i]);
			break;
		}
	}

	cr_end();
}
*/

struct {
	struct rp2040_hwspi     dev_spi;
	struct w5500            dev_w5500;
	usb_keyboard_rpc_t      keyboard_chan;
	uint16_t                usb_serial[sizeof(uint64_t)*2]; /* UTF-16 */
	struct lib9p_srv        srv;
} globals;

static COROUTINE dhcp_cr(void *) {
	cr_begin();

	dhcp_client_main(lo_box_w5500_if_as_net_iface(&globals.dev_w5500), "harness");

	cr_end();
}

static COROUTINE read9p_cr(void *) {
	cr_begin();

	lo_interface net_iface iface = lo_box_w5500_if_as_net_iface(&globals.dev_w5500);
	lo_interface net_stream_listener listener = LO_CALL(iface, tcp_listen, CONFIG_9P_PORT);

	lib9p_srv_read_cr(&globals.srv, listener);

	cr_end();
}

const char *const hexdig = "0123456789ABCDEF";
static_assert(CONFIG_9P_SRV_MAX_REQS*_CONFIG_9P_NUM_SOCKS <= 16);

COROUTINE init_cr(void *) {
	cr_begin();

	/* NOR flash chips have a (bog-?)standard "RUID" "Read Unique
	 * ID" instruction; use our flash chip's unique ID as the
	 * basis for our serial numbers.  */
	uint64_t flash_id64;
	static_assert(sizeof(flash_id64) == FLASH_UNIQUE_ID_SIZE_BYTES);
	flash_get_unique_id((uint8_t *)&flash_id64);
	uint32_t flash_id32 = hash(&flash_id64, sizeof(flash_id64));
	static_assert(sizeof(flash_id32) == sizeof(hash(NULL, 0)));
	uint8_t flash_id24[3] = {
		(uint8_t)((flash_id32 >> 16) & 0xFF),
		(uint8_t)((flash_id32 >>  8) & 0xFF),
		(uint8_t)((flash_id32 >>  0) & 0xFF),
	};

	rp2040_hwspi_init(&globals.dev_spi, "W5500", RP2040_HWSPI_0,
	                  SPI_MODE_0, /* the W5500 supports mode 0 or mode 3 */
	                  42500000, /* min(w5500, hwspi); w5500=80MHz; hwspi=42.5MHz, see rp2040_hwspi.h for a comment about why this is so low */
	                  30, /* W5500 datasheet says min(T_CS = SCSn High Time) = 30ns */
	                  0,  /* bogus write write data when doing a read */
	                  16, /* PIN_MISO */
	                  19, /* PIN_MOSI */
	                  18, /* PIN_CLK */
	                  17, /* PIN_CS */
	                  0, 1, 2, 3); /* DMA channels */
	w5500_init(&globals.dev_w5500, "W5500",
	           lo_box_rp2040_hwspi_as_spi(&globals.dev_spi),
	           21, /* PIN_INTR */
	           20, /* PIN_RESET */
	           ((struct net_eth_addr){{
		           /* vendor ID: "Wiznet" */
		           0x00, 0x08, 0xDC,
		           /* serial number */
		           flash_id24[0], flash_id24[1], flash_id24[2],
	           }}));

	static_assert(sizeof(flash_id64)*2 == LM_ARRAY_LEN(globals.usb_serial));
	for (size_t i = 0; i < LM_ARRAY_LEN(globals.usb_serial); i++)
		globals.usb_serial[i] = hexdig[(flash_id64 >> ((sizeof(flash_id64)*8)-((i+1)*4))) & 0xF];
	usb_common_earlyinit(globals.usb_serial, sizeof(globals.usb_serial));
	usb_keyboard_init();
	usb_common_lateinit();

	globals.keyboard_chan = (usb_keyboard_rpc_t){0};

	globals.srv.rootdir = get_root;

	/* set up coroutines **************************************************/
	coroutine_add("usb_common", usb_common_cr, NULL);
	coroutine_add("usb_keyboard", usb_keyboard_cr, &globals.keyboard_chan);
	//coroutine_add("hello_world", hello_world_cr, &globals.keyboard_chan);
	coroutine_add("dhcp", dhcp_cr, NULL);
	for (int i = 0; i < _CONFIG_9P_NUM_SOCKS; i++) {
		char name[] = {'r', 'e', 'a', 'd', '-', hexdig[i], '\0'};
		coroutine_add(name, read9p_cr, NULL);
	}
	for (int i = 0; i < CONFIG_9P_SRV_MAX_REQS*_CONFIG_9P_NUM_SOCKS; i++) {
		char name[] = {'w', 'r', 'i', 't', 'e', '-', hexdig[i], '\0'};
		coroutine_add(name, lib9p_srv_write_cr, &globals.srv);
	}

	cr_exit();
}

int main() {
	bootclock = rp2040_hwtimer(0);
	stdio_uart_init();
	/* char *hdr = "=" * (80-strlen("info : MAIN: ")); */
	infof("===================================================================");
	coroutine_add("init", init_cr, NULL);
	coroutine_main();
}