//-----------------------------------------------------------------------------
// 2023 Ahoy, https://www.mikrocontroller.net/topic/525778
// Creative Commons - http://creativecommons.org/licenses/by-nc-sa/3.0/de/
//-----------------------------------------------------------------------------


#if defined(CONFIG_IDF_TARGET_ESP32S3)
#if defined(ETHERNET)
#ifndef __ETH_SPI_H__
#define __ETH_SPI_H__

#pragma once

#include <Arduino.h>
#include <esp_netif.h>
#include <WiFiGeneric.h>
#include <driver/spi_master.h>

// Functions from WiFiGeneric
void tcpipInit();
void add_esp_interface_netif(esp_interface_t interface, esp_netif_t* esp_netif);

class EthSpi {
    public:

        EthSpi() :
            eth_handle(nullptr),
            eth_netif(nullptr) {}

        void begin(int8_t pin_miso, int8_t pin_mosi, int8_t pin_sclk, int8_t pin_cs, int8_t pin_int, int8_t pin_rst) {
            gpio_reset_pin(static_cast<gpio_num_t>(pin_rst));
            gpio_set_direction(static_cast<gpio_num_t>(pin_rst), GPIO_MODE_OUTPUT);
            gpio_set_level(static_cast<gpio_num_t>(pin_rst), 0);

            gpio_reset_pin(static_cast<gpio_num_t>(pin_sclk));
            gpio_reset_pin(static_cast<gpio_num_t>(pin_mosi));
            gpio_reset_pin(static_cast<gpio_num_t>(pin_miso));
            gpio_reset_pin(static_cast<gpio_num_t>(pin_cs));
            gpio_set_pull_mode(static_cast<gpio_num_t>(pin_miso), GPIO_PULLUP_ONLY);

            // Workaround, because calling gpio_install_isr_service directly causes issues with attachInterrupt later
            attachInterrupt(digitalPinToInterrupt(pin_int), nullptr, CHANGE);
            detachInterrupt(digitalPinToInterrupt(pin_int));
            gpio_reset_pin(static_cast<gpio_num_t>(pin_int));
            gpio_set_pull_mode(static_cast<gpio_num_t>(pin_int), GPIO_PULLUP_ONLY);

            spi_bus_config_t buscfg = {
                .mosi_io_num = pin_mosi,
                .miso_io_num = pin_miso,
                .sclk_io_num = pin_sclk,
                .quadwp_io_num = -1,
                .quadhd_io_num = -1,
                .data4_io_num = -1,
                .data5_io_num = -1,
                .data6_io_num = -1,
                .data7_io_num = -1,
                .max_transfer_sz = 0, // uses default value internally
                .flags = 0,
                .intr_flags = 0
            };

            ESP_ERROR_CHECK(spi_bus_initialize(SPI3_HOST, &buscfg, SPI_DMA_CH_AUTO));

            spi_device_interface_config_t devcfg = {
                .command_bits = 16, // actually address phase
                .address_bits = 8, // actually command phase
                .dummy_bits = 0,
                .mode = 0,
                .duty_cycle_pos = 0,
                .cs_ena_pretrans = 0, // only 0 supported
                .cs_ena_posttrans = 0, // only 0 supported
                .clock_speed_hz = 20000000, // stable with on OpenDTU Fusion Shield
                .input_delay_ns = 0,
                .spics_io_num = pin_cs,
                .flags = 0,
                .queue_size = 20,
                .pre_cb = nullptr,
                .post_cb = nullptr
            };

            spi_device_handle_t spi;
            ESP_ERROR_CHECK(spi_bus_add_device(SPI3_HOST, &devcfg, &spi));

            // Reset sequence
            delayMicroseconds(500);
            gpio_set_level(static_cast<gpio_num_t>(pin_rst), 1);
            delayMicroseconds(1000);

            // Arduino function to start networking stack if not already started
            tcpipInit();

            ESP_ERROR_CHECK(tcpip_adapter_set_default_eth_handlers()); // ?

            eth_w5500_config_t w5500_config = ETH_W5500_DEFAULT_CONFIG(spi);
            w5500_config.int_gpio_num = pin_int;

            eth_mac_config_t mac_config = ETH_MAC_DEFAULT_CONFIG();
            mac_config.rx_task_stack_size = 4096;
            esp_eth_mac_t *mac = esp_eth_mac_new_w5500(&w5500_config, &mac_config);

            eth_phy_config_t phy_config = ETH_PHY_DEFAULT_CONFIG();
            phy_config.reset_gpio_num = -1;
            esp_eth_phy_t *phy = esp_eth_phy_new_w5500(&phy_config);

            esp_eth_config_t eth_config = ETH_DEFAULT_CONFIG(mac, phy);
            ESP_ERROR_CHECK(esp_eth_driver_install(&eth_config, &eth_handle));

            // Configure MAC address
            uint8_t mac_addr[6];
            ESP_ERROR_CHECK(esp_efuse_mac_get_default(mac_addr));
            mac_addr[5] |= 0x03; // derive ethernet MAC address from base MAC address
            ESP_ERROR_CHECK(esp_eth_ioctl(eth_handle, ETH_CMD_S_MAC_ADDR, mac_addr));

            esp_netif_config_t netif_config = ESP_NETIF_DEFAULT_ETH();
            eth_netif = esp_netif_new(&netif_config);

            ESP_ERROR_CHECK(esp_netif_attach(eth_netif, esp_eth_new_netif_glue(eth_handle)));

            // Add to Arduino
            add_esp_interface_netif(ESP_IF_ETH, eth_netif);

            ESP_ERROR_CHECK(esp_eth_start(eth_handle));
        }

        String macAddress() {
            uint8_t mac_addr[6] = {0, 0, 0, 0, 0, 0};
            esp_eth_ioctl(eth_handle, ETH_CMD_G_MAC_ADDR, mac_addr);
            char mac_addr_str[24];
            snprintf(mac_addr_str, sizeof(mac_addr_str), "%02X:%02X:%02X:%02X:%02X:%02X", mac_addr[0], mac_addr[1], mac_addr[2], mac_addr[3], mac_addr[4], mac_addr[5]);
            return String(mac_addr_str);
        }


    private:
        esp_eth_handle_t eth_handle;
        esp_netif_t *eth_netif;
};

#endif /*__ETH_SPI_H__*/
#endif /*ETHERNET*/
#endif /*CONFIG_IDF_TARGET_ESP32S3*/