/**
 * Portal panel firmware — W5500 UDP + WS2812 (Pico SDK).
 *
 * UDP protocol (port 50007):
 *   - N×3 bytes: raw RGB → strip 0 (N = 1…MAX_LEDS)
 *   - 1 + N×3 bytes: strip_id (byte 0) + RGB
 *       strip_id 0…MAX_STRIPS-1 → that strip
 *       strip_id 255 → all active strips
 *   - 5 bytes "PIN\\0" + gpio: bind strip 0 to gpio
 *   - 8 bytes "PIN\\0" + strip + gpio + len_lo + len_hi: bind strip (len=0 → unset)
 *   - 4 bytes "SHOW": reserved (frames already show on receive)
 *
 * One Pico can drive up to MAX_STRIPS displays on separate GPIOs.
 * Each strip’s pixel count comes from its own UDP frame length (strips may differ).
 * MAX_LEDS is per-strip capacity.
 */

#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[MAX_STRIPS][LED_RGB_BYTES];
static uint16_t g_frame_pixels[MAX_STRIPS];
static uint16_t g_strip_leds[MAX_STRIPS];
static uint8_t g_frame_dirty[MAX_STRIPS];
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(unsigned int strip) {
    if (!ws2812_strip_active(strip)) {
        return;
    }
    uint8_t one[3] = {255, 0, 0};
    ws2812_set_rgb(strip, one, 1);
    ws2812_show(strip);
    sleep_ms(150);
    one[0] = 0;
    one[1] = 255;
    ws2812_set_rgb(strip, one, 1);
    ws2812_show(strip);
    sleep_ms(150);
    one[1] = 0;
    one[2] = 255;
    ws2812_set_rgb(strip, one, 1);
    ws2812_show(strip);
    sleep_ms(150);
    one[2] = 0;
    ws2812_set_rgb(strip, one, 1);
    ws2812_show(strip);
}

static int buffer_frame(unsigned int strip, const uint8_t *rgb, uint16_t nbytes) {
    if (strip >= MAX_STRIPS || !ws2812_strip_active(strip)) {
        return -1;
    }
    if (nbytes == 0 || (nbytes % 3u) != 0) {
        return -1;
    }
    uint16_t pixels = nbytes / 3u;
    if (pixels > MAX_LEDS) {
        pixels = MAX_LEDS;
        nbytes = (uint16_t)(pixels * 3u);
    }
    memcpy(g_pixel_buf[strip], rgb, nbytes);
    if (nbytes < LED_RGB_BYTES) {
        memset(g_pixel_buf[strip] + nbytes, 0, LED_RGB_BYTES - nbytes);
    }
    g_frame_pixels[strip] = pixels;
    g_frame_dirty[strip] = 1;
    return 0;
}

static void buffer_frame_all(const uint8_t *rgb, uint16_t nbytes) {
    for (unsigned int s = 0; s < MAX_STRIPS; s++) {
        if (ws2812_strip_active(s)) {
            buffer_frame(s, rgb, nbytes);
        }
    }
}

static void show_dirty_frames(void) {
    for (unsigned int s = 0; s < MAX_STRIPS; s++) {
        if (!g_frame_dirty[s]) {
            continue;
        }
        ws2812_set_rgb(s, g_pixel_buf[s], g_frame_pixels[s]);
        ws2812_show(s);
        g_frame_dirty[s] = 0;
    }
}

static int pin_is_reserved(uint8_t pin) {
    switch (pin) {
    case PIN_CS:
    case PIN_SCK:
    case PIN_MOSI:
    case PIN_MISO:
    case PIN_RST:
    case PIN_LED_STATUS:
        return 1;
    default:
        return pin > 29;
    }
}

static void handle_pin_command(uint8_t strip, uint8_t pin, uint16_t leds) {
    if (strip >= MAX_STRIPS) {
        printf("PIN strip %u out of range (max %u)\n", (unsigned)strip, MAX_STRIPS);
        return;
    }
    if (pin_is_reserved(pin)) {
        printf("PIN GP%u rejected (reserved)\n", (unsigned)pin);
        return;
    }
    if (leds > MAX_LEDS) {
        printf("PIN leds %u clamped to max_leds=%u\n", (unsigned)leds, MAX_LEDS);
        leds = MAX_LEDS;
    }
    for (unsigned int s = 0; s < MAX_STRIPS; s++) {
        if (s != strip && ws2812_strip_active(s) && ws2812_get_pin(s) == pin) {
            printf("PIN GP%u: releasing strip %u\n", (unsigned)pin, s);
            ws2812_release_strip(s);
            g_strip_leds[s] = 0;
            g_frame_pixels[s] = 0;
            g_frame_dirty[s] = 0;
        }
    }
    if (ws2812_set_pin(strip, pin) != 0) {
        printf("PIN strip %u GP%u failed (no PIO SM?)\n", (unsigned)strip, (unsigned)pin);
        return;
    }
    g_strip_leds[strip] = leds;
    if (leds) {
        printf("strip %u ws2812=GP%u leds=%u\n", (unsigned)strip,
               (unsigned)ws2812_get_pin(strip), (unsigned)leds);
    } else {
        printf("strip %u ws2812=GP%u\n", (unsigned)strip, (unsigned)ws2812_get_pin(strip));
    }
}

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

    if (len == 5 && data[0] == 'P' && data[1] == 'I' && data[2] == 'N' && data[3] == 0) {
        handle_pin_command(0, data[4], 0);
        return;
    }

    if (len == 8 && data[0] == 'P' && data[1] == 'I' && data[2] == 'N' && data[3] == 0) {
        uint16_t leds = (uint16_t)data[6] | ((uint16_t)data[7] << 8);
        handle_pin_command(data[4], data[5], leds);
        return;
    }

    if (len >= 3 && (len % 3) == 0) {
        buffer_frame(0, data, (uint16_t)len);
        return;
    }

    if (len >= 4 && ((len - 1) % 3) == 0) {
        uint8_t id = data[0];
        uint16_t nbytes = (uint16_t)(len - 1);
        if (id == 255) {
            buffer_frame_all(data + 1, nbytes);
            return;
        }
        if (id < MAX_STRIPS) {
            buffer_frame(id, data + 1, nbytes);
            return;
        }
        if (id == (uint8_t)PANEL_ID) {
            buffer_frame(0, data + 1, nbytes);
            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);
    }
}

static void print_strip_map(void) {
    printf("strips=%d", MAX_STRIPS);
    for (unsigned int s = 0; s < MAX_STRIPS; s++) {
        if (ws2812_strip_active(s)) {
            if (g_strip_leds[s]) {
                printf(" [%u]=GP%u/%u", s, ws2812_get_pin(s), g_strip_leds[s]);
            } else {
                printf(" [%u]=GP%u", s, ws2812_get_pin(s));
            }
        }
    }
    printf("\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("max_leds=%d max_strips=%d panel_id=%d mac=02:50:52:54:4C:%02X ip=10.1.1.%u\n",
           MAX_LEDS, MAX_STRIPS, PANEL_ID, (unsigned)PANEL_ID, (unsigned)STATIC_IP_OCT4);

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

    ws2812_init(MAX_LEDS);
    memset(g_pixel_buf, 0, sizeof(g_pixel_buf));
    memset(g_frame_pixels, 0, sizeof(g_frame_pixels));
    memset(g_strip_leds, 0, sizeof(g_strip_leds));
    memset(g_frame_dirty, 0, sizeof(g_frame_dirty));

    static const unsigned int default_pins[MAX_STRIPS] = {PIN_WS2812, PIN_WS2812_1};
    for (unsigned int s = 0; s < MAX_STRIPS; s++) {
        if (ws2812_set_pin(s, default_pins[s]) == 0) {
            led_boot_test(s);
        } else {
            printf("default strip %u GP%u failed\n", s, default_pins[s]);
        }
    }
    print_strip_map();

    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();
        show_dirty_frames();
        if (++heartbeat >= 500) {
            gpio_xor_mask(1u << PIN_LED_STATUS);
            heartbeat = 0;
        }
        sleep_ms(1);
    }
}