#include "esp_task_wdt.h" // watchdogs
#include <WiFi.h> // WiFi connection
#include <ESPAsyncWebServer.h>
#include <stdio.h>
#include "driver/gpio.h"
#include <ESPmDNS.h>

///////////////////////////////////////////////////////////////////////////////
/// Watchdogs Settings

#define WDT_TIMEOUT 60000
#define WDT_CONFIG_FREERTOS_NUMBER_OF_CORES 1 // If one core doesn't work, try 2

esp_task_wdt_config_t twdt_config = {
    .timeout_ms = WDT_TIMEOUT,
    .idle_core_mask = (1 << WDT_CONFIG_FREERTOS_NUMBER_OF_CORES) - 1, // Bitmask of all cores
    .trigger_panic = true,
}; // Bugfixes for hardware watchdog on arduino-esp32 3.x

///////////////////////////////////////////////////////////////////////////////
/// WiFi Settings

//#define WIFI_SSID "FlannelFlat1"
//#define WIFI_PASSWORD "CosySquares4Life:3"

#define WIFI_SSID "Hacklab"
#define WIFI_PASSWORD "piranhas"
#define WIFI_HOSTNAME "MediaServerSwitch"

///////////////////////////////////////////////////////////////////////////////
/// HTTP Server Setup

AsyncWebServer server(80);

///////////////////////////////////////////////////////////////////////////////
/// Pin Setup

#define PIN_POWER_RELAY 23
#define PIN_RESTART_RELAY 19
#define PIN_STATUS_LED 35
#define PIN_POWER_BTN 27

const char* WiFiCodeToString(int code) {
    const char* status;
    switch (code) {
        case 0: status = "IDLE STATUS"; break;
        case 1: status = "NO SSID AVAILABLE"; break;
        case 2: status = "SCAN COMPLETE"; break;
        case 3: status = "CONNECTED"; break;
        case 4: status = "CONNECT FAILED"; break;
        case 5: status = "CONNECTION L\sOST"; break;
        case 6: status = "DISCONNECTED"; break;
        case 255: status = "NO SHIELD"; break;
        default: status = "UNKNOWN"; break;
    }

    return status;
}

void setup() {
    Serial.begin(9600);

    ///////////////////////////////////////////////////////////////////////////
    /// Watchdog Setup
    Serial.print("Configuring WDT... ");
    esp_task_wdt_deinit(); // WDT is enabled by default, deinit
    esp_task_wdt_init(&twdt_config); // Enable panic so ESP32 restarts
    esp_task_wdt_add(NULL); // Add current thread to WDT watch
    Serial.println("Success");

    ///////////////////////////////////////////////////////////////////////////
    /// Pin Setup

    pinMode(PIN_POWER_RELAY, OUTPUT); // Power Button
    pinMode(PIN_RESTART_RELAY, OUTPUT); // Restart Button
    pinMode(PIN_STATUS_LED, INPUT); // Status LED
    pinMode(PIN_POWER_BTN, INPUT); // Power Button Passthrough

    ///////////////////////////////////////////////////////////////////////////
    /// WiFi Setup
    
    esp_task_wdt_reset(); // Feed the watchdog

    Serial.print("Setting up WiFi... ");
    WiFi.mode(WIFI_STA);
    WiFi.setHostname(WIFI_HOSTNAME);
    MDNS.begin(WIFI_HOSTNAME);
    WiFi.begin(WIFI_SSID, WIFI_PASSWORD);
    Serial.print("Connecting to Network... ");

    unsigned short count = 0;
    unsigned long last = millis();
    while (WiFi.status() != WL_CONNECTED) {
        if (count > 60) {
            Serial.println("Failed to connect, restarting");
            ESP.restart();
        } else if (millis() - last > 1000) {
            Serial.print(".");
            last = millis();
            count++;
        }
    }

    WiFi.persistent(false);

    Serial.print(" Connected with IP: ");
    Serial.print(WiFi.localIP());
    Serial.print(" and Hostname: ");
    Serial.println(WIFI_HOSTNAME);

    esp_task_wdt_reset(); // Feed the watchdog

    int ch = WiFi.channel();
    bool is5GHz = (ch >= 36);
    Serial.printf("Channel: %d (%s GHz), RSSI: %d dBm\n", ch, is5GHz ? "5" : "2.4", WiFi.RSSI());

    ///////////////////////////////////////////////////////////////////////////
    /// Web Server

    server.on("/", HTTP_GET, [](AsyncWebServerRequest *request) {
        request->send(200, "text/plain",
        "/ping           Pong\n"
        "/status         Get ESP and PC status\n"
        "/power          Press the power button\n"
        "/power-long     Hold down the power button (for force stops)\n"
        "/restart-pc     Press the restart button on the PC\n"
        "/restart-ESP    Shut down the server and restart the whole ESP\n");
    });

    server.on("/ping", HTTP_GET, [](AsyncWebServerRequest *request) {
        request->send(200, "text/plain", "pong");
    });

    server.on("/status", HTTP_GET, [ch, is5GHz](AsyncWebServerRequest *request) {
        char* result;
        asprintf(&result, "IP: %s, Hostname: %s, Status: %s, Channel: %d (%s GHz), RSSI: %d dBm\n", WiFi.localIP().toString().c_str(), WIFI_HOSTNAME, WiFiCodeToString(WiFi.status()), ch, is5GHz ? "5" : "2.4", WiFi.RSSI());
        request->send(200, "text/plain", result);
        free(result);
    });

    server.on("/power", HTTP_POST, [](AsyncWebServerRequest *request) {
        digitalWrite(PIN_POWER_RELAY, HIGH);
        delay(500);
        digitalWrite(PIN_POWER_RELAY, LOW);
        request->send(200, "text/plain", "200 OK");
    });

    server.on("/power-long", HTTP_POST, [](AsyncWebServerRequest *request) {
        digitalWrite(PIN_POWER_RELAY, HIGH);
        delay(5000);
        digitalWrite(PIN_POWER_RELAY, LOW);
        request->send(200, "text/plain", "200 OK");
    });

    server.on("/restart-pc", HTTP_POST, [](AsyncWebServerRequest *request) {
        digitalWrite(PIN_RESTART_RELAY, HIGH);
        delay(1000);
        digitalWrite(PIN_RESTART_RELAY, LOW);
        request->send(200, "text/plain", "200 OK");
    });

    server.on("/restart-ESP", HTTP_POST, [](AsyncWebServerRequest *request) {
        request->send(202, "text/plain", "202 Accepted. Good Night.");
        delay(500);
        server.end();
        ESP.restart();
    });

    server.on("/activate", HTTP_POST, [](AsyncWebServerRequest *request) {
        if (!request->hasParam("pin", true) || !request->hasParam("duration", true)) {
            request->send(400, "text/plain", "400 Bad Request. Missing 'pin' or 'duration' parameter");
            return;
        }

        int pin = request->getParam("pin", true)->value().toInt();
        long duration = strtol(request->getParam("duration", true)->value().c_str(), NULL, 10);

        if (!GPIO_IS_VALID_GPIO((gpio_num_t)pin)) {
            request->send(400, "text/plain", "Invalid pin for this ESP32");
            return;
        }

        if (duration <= 0 || duration > 3600000) {
            request->send(400, "text/plain", "400 Bad Request. Duration must be between 1ms and 3600000ms");
            return;
        }

        gpio_io_config_t* pin_mode;
        gpio_get_io_config((gpio_num_t)pin, pin_mode);
        if (pin_mode->oe == true) {
            if (pin_mode->ie != true) {
                request->send(400, "text/plain", "Pin is configured as input");
                return;
            }

            // Configure pin as output
            gpio_config_t config = {};
            config.pin_bit_mask = (1ULL << pin);
            config.mode = GPIO_MODE_OUTPUT;
            config.pull_up_en = GPIO_PULLUP_DISABLE;
            config.pull_down_en = GPIO_PULLDOWN_DISABLE;
            config.intr_type = GPIO_INTR_DISABLE;

            if (gpio_config(&config) != ESP_OK) {
                request->send(400, "text/plain", "Bad Request. Cannot configure pin as output");
                return;
            }
        }

        gpio_set_level((gpio_num_t)pin, HIGH);
        delay(duration);
        gpio_set_level((gpio_num_t)pin, LOW);
        delay(10);  // allow change to propagate

        // unconfigure pin
        gpio_reset_pin((gpio_num_t)pin);

        request->send(200, "text/plain", "OK");
    });

    server.begin();
}

unsigned long last = millis();

void loop() {
    if (millis() - last > 10000) {
        Serial.print("Heartbeat. WiFi Status: ");
        Serial.println(WiFiCodeToString(WiFi.status()));
        esp_task_wdt_reset(); // Feed the watchdog
        last = millis();
    }
    if (WiFi.status() != WL_CONNECTED) { // you can use WiFi.setAutoReconnect(true); but i rather this for custom behaviour.
        Serial.println("Disconnected from network, restarting.");
        ESP.restart();
    }
}