/**
 * Portal panel firmware — W5500 UDP + WS2812 (Pico SDK).
 *
 * UDP protocol (port 50007):
 *   - N×3 bytes: raw RGB (N = NUM_LEDS), show immediately
 *   - N×3+1 bytes: panel_id (byte 0) + RGB; panel_id 255 = any panel
 *   - 4 bytes "SHOW": refresh buffered pixels (for split frame/show sync)
 */

#include <stdio.h>
#include <stdint.h>
#include <string.h>

#include "board_config.h"
#include "wizchip_conf.h"
#include "dhcp.h"
#include "socket.h"
#include "timer.h"
#include "wizchip_spi.h"
#include "ws2812_led.h"

#include "hardware/gpio.h"
#include "pico/stdlib.h"

#define SOCKET_UDP 1
#define SOCKET_DHCP 0
#define ETH_BUF_SIZE 2048
#define DHCP_RETRY_MAX 10

static wiz_NetInfo g_net_info = {
    .mac = MAC_ADDR,
    .ip = STATIC_IP,
    .sn = STATIC_SN,
    .gw = STATIC_GW,
    .dns = STATIC_DNS,
#if USE_DHCP
    .dhcp = NETINFO_DHCP,
#else
    .dhcp = NETINFO_STATIC,
#endif
};

static uint8_t g_eth_buf[ETH_BUF_SIZE];
static uint8_t g_pixel_buf[LED_RGB_BYTES];
static volatile uint16_t g_ms_tick;
static uint8_t g_dhcp_ready;

static void dhcp_timer_cb(void) {
    g_ms_tick++;
    if (g_ms_tick >= 999) {
        g_ms_tick = 0;
        DHCP_time_handler();
    }
}

static void dhcp_assign(void) {
    getIPfromDHCP(g_net_info.ip);
    getGWfromDHCP(g_net_info.gw);
    getSNfromDHCP(g_net_info.sn);
    getDNSfromDHCP(g_net_info.dns);
    g_net_info.dhcp = NETINFO_DHCP;
    network_initialize(g_net_info);
    print_network_information(g_net_info);
    g_dhcp_ready = 1;
}

static void dhcp_conflict(void) {
    printf("DHCP conflict\n");
}

static int network_bring_up(void) {
#if USE_DHCP
    uint8_t retries = 0;
    DHCP_init(SOCKET_DHCP, g_eth_buf);
    reg_dhcp_cbfunc(dhcp_assign, dhcp_assign, dhcp_conflict);
    wizchip_1ms_timer_initialize(dhcp_timer_cb);

    while (!g_dhcp_ready && retries < DHCP_RETRY_MAX) {
        int8_t rv = DHCP_run();
        if (rv == DHCP_IP_LEASED) {
            g_dhcp_ready = 1;
            break;
        }
        if (rv == DHCP_FAILED) {
            retries++;
        }
        wizchip_delay_ms(250);
    }
    if (!g_dhcp_ready) {
        printf("DHCP failed, using static IP\n");
        g_net_info.dhcp = NETINFO_STATIC;
        network_initialize(g_net_info);
        print_network_information(g_net_info);
    }
#else
    network_initialize(g_net_info);
    print_network_information(g_net_info);
#endif
    return 0;
}

static int udp_socket_open(void) {
    int8_t sn = socket(SOCKET_UDP, Sn_MR_UDP, UDP_PORT, 0);
    if (sn != SOCKET_UDP) {
        printf("UDP socket open failed: %d\n", sn);
        return -1;
    }
    printf("UDP listening on port %d\n", UDP_PORT);
    return 0;
}

static void led_boot_test(void) {
    printf("LED boot test on GP%d (%d pixels)\n", PIN_WS2812, NUM_LEDS);
    ws2812_fill(255, 0, 0);
    ws2812_show();
    sleep_ms(500);
    ws2812_fill(0, 255, 0);
    ws2812_show();
    sleep_ms(500);
    ws2812_fill(0, 0, 0);
    ws2812_show();
}

static int handle_frame(const uint8_t *rgb, uint16_t len) {
    if (len != LED_RGB_BYTES) {
        printf("frame reject len=%u want=%u\n", (unsigned)len, (unsigned)LED_RGB_BYTES);
        return -1;
    }
    ws2812_set_rgb(rgb, NUM_LEDS);
    ws2812_show();
    return 0;
}

static void handle_packet(const uint8_t *data, int16_t len) {
    if (len == 4 && memcmp(data, "SHOW", 4) == 0) {
        ws2812_set_rgb(g_pixel_buf, NUM_LEDS);
        ws2812_show();
        return;
    }

    if (len == LED_RGB_BYTES) {
        memcpy(g_pixel_buf, data, LED_RGB_BYTES);
        handle_frame(data, (uint16_t)len);
        return;
    }

    if (len == LED_RGB_BYTES + 1) {
        uint8_t panel = data[0];
        if (panel != 255 && panel != (uint8_t)PANEL_ID) {
            return;
        }
        memcpy(g_pixel_buf, data + 1, LED_RGB_BYTES);
        handle_frame(data + 1, LED_RGB_BYTES);
        return;
    }
}

static void poll_udp(void) {
    while (1) {
        uint16_t rx = getSn_RX_RSR(SOCKET_UDP);
        if (rx == 0) {
            return;
        }
        if (rx > ETH_BUF_SIZE) {
            rx = ETH_BUF_SIZE;
        }

        uint8_t src_ip[4];
        uint16_t src_port;
        int16_t n = recvfrom(SOCKET_UDP, g_eth_buf, rx, src_ip, &src_port);
        if (n <= 0) {
            return;
        }
        handle_packet(g_eth_buf, n);
    }
}

int main(void) {
    stdio_init_all();
    sleep_ms(2000);

    gpio_init(PIN_LED_STATUS);
    gpio_set_dir(PIN_LED_STATUS, GPIO_OUT);

    printf("portal panel firmware (Pico SDK)\n");
    printf("LEDs=%d panel_id=%d mac=02:50:52:54:4C:%02X ip=10.1.1.%u\n",
           NUM_LEDS, PANEL_ID, (unsigned)PANEL_ID, (unsigned)STATIC_IP_OCT4);

    wizchip_spi_initialize();
    wizchip_cris_initialize();
    wizchip_reset();
    wizchip_initialize();
    wizchip_check();

    ws2812_init(PIN_WS2812, NUM_LEDS);
    memset(g_pixel_buf, 0, sizeof(g_pixel_buf));
    led_boot_test();

    network_bring_up();
    if (udp_socket_open() != 0) {
        while (1) {
            gpio_xor_mask(1u << PIN_LED_STATUS);
            sleep_ms(100);
        }
    }

    uint32_t heartbeat = 0;
    while (1) {
#if USE_DHCP
        DHCP_run();
#endif
        poll_udp();
        if (++heartbeat >= 500) {
            gpio_xor_mask(1u << PIN_LED_STATUS);
            heartbeat = 0;
        }
        sleep_ms(1);
    }
}