#include "bme280.h"
#include "bme280_defs.h"
#include "driver/i2c.h"
#include <u8g2.h>
#include "u8g2_esp32_hal.h"
#include <esp_log.h>
#include <esp_wifi.h>
#include "freertos/event_groups.h"
#include "nvs_flash.h"
#include <esp_http_server.h>
#include <sys/param.h>

#define WIFI_SSID     "Netzknecht"
#define WIFI_PASS     "***REMOVED***"
#define WIFI_RETRIES  10

static EventGroupHandle_t s_wifi_event_group;
#define WIFI_CONNECTED_BIT BIT0
#define WIFI_FAIL_BIT      BIT1

static const char *TAG = "wifi station";
static int s_retry_num = 0;

char cur_value_str[255];

/* An HTTP GET handler */
static esp_err_t hello_get_handler(httpd_req_t *req)
{
    char*  buf;
    size_t buf_len;

    /* Get header value string length and allocate memory for length + 1,
     * extra byte for null termination */
    buf_len = httpd_req_get_hdr_value_len(req, "Host") + 1;
    if (buf_len > 1) {
        buf = malloc(buf_len);
        /* Copy null terminated value string into buffer */
        if (httpd_req_get_hdr_value_str(req, "Host", buf, buf_len) == ESP_OK) {
            ESP_LOGI(TAG, "Found header => Host: %s", buf);
        }
        free(buf);
    }

    buf_len = httpd_req_get_hdr_value_len(req, "Test-Header-2") + 1;
    if (buf_len > 1) {
        buf = malloc(buf_len);
        if (httpd_req_get_hdr_value_str(req, "Test-Header-2", buf, buf_len) == ESP_OK) {
            ESP_LOGI(TAG, "Found header => Test-Header-2: %s", buf);
        }
        free(buf);
    }

    buf_len = httpd_req_get_hdr_value_len(req, "Test-Header-1") + 1;
    if (buf_len > 1) {
        buf = malloc(buf_len);
        if (httpd_req_get_hdr_value_str(req, "Test-Header-1", buf, buf_len) == ESP_OK) {
            ESP_LOGI(TAG, "Found header => Test-Header-1: %s", buf);
        }
        free(buf);
    }

    /* Read URL query string length and allocate memory for length + 1,
     * extra byte for null termination */
    buf_len = httpd_req_get_url_query_len(req) + 1;
    if (buf_len > 1) {
        buf = malloc(buf_len);
        if (httpd_req_get_url_query_str(req, buf, buf_len) == ESP_OK) {
            ESP_LOGI(TAG, "Found URL query => %s", buf);
            char param[32];
            /* Get value of expected key from query string */
            if (httpd_query_key_value(buf, "query1", param, sizeof(param)) == ESP_OK) {
                ESP_LOGI(TAG, "Found URL query parameter => query1=%s", param);
            }
            if (httpd_query_key_value(buf, "query3", param, sizeof(param)) == ESP_OK) {
                ESP_LOGI(TAG, "Found URL query parameter => query3=%s", param);
            }
            if (httpd_query_key_value(buf, "query2", param, sizeof(param)) == ESP_OK) {
                ESP_LOGI(TAG, "Found URL query parameter => query2=%s", param);
            }
        }
        free(buf);
    }

    /* Set some custom headers */
    httpd_resp_set_hdr(req, "Custom-Header-1", "Custom-Value-1");
    httpd_resp_set_hdr(req, "Custom-Header-2", "Custom-Value-2");

    /* Send response with custom headers and body set as the
     * string passed in user context*/
    const char* resp_str = cur_value_str;
    httpd_resp_send(req, resp_str, strlen(resp_str));

    /* After sending the HTTP response the old HTTP request
     * headers are lost. Check if HTTP request headers can be read now. */
    if (httpd_req_get_hdr_value_len(req, "Host") == 0) {
        ESP_LOGI(TAG, "Request headers lost");
    }
    return ESP_OK;
}

static httpd_uri_t hello = {
    .uri       = "/hello",
    .method    = HTTP_GET,
    .handler   = hello_get_handler,
    /* Let's pass response string in user
     * context to demonstrate it's usage */
    .user_ctx  = "Hello World!"
};

static httpd_handle_t start_webserver(void)
{
    httpd_handle_t server = NULL;
    httpd_config_t config = HTTPD_DEFAULT_CONFIG();

    // Start the httpd server
    ESP_LOGI(TAG, "Starting server on port: '%d'", config.server_port);
    if (httpd_start(&server, &config) == ESP_OK) {
        // Set URI handlers
        ESP_LOGI(TAG, "Registering URI handlers");
        httpd_register_uri_handler(server, &hello);
        return server;
    }

    ESP_LOGI(TAG, "Error starting server!");
    return NULL;
}

static void stop_webserver(httpd_handle_t server)
{
    // Stop the httpd server
    httpd_stop(server);
}

static void disconnect_handler(void* arg, esp_event_base_t event_base,
                               int32_t event_id, void* event_data)
{
    httpd_handle_t* server = (httpd_handle_t*) arg;
    if (*server) {
        ESP_LOGI(TAG, "Stopping webserver");
        stop_webserver(*server);
        *server = NULL;
    }
}

static void connect_handler(void* arg, esp_event_base_t event_base,
                            int32_t event_id, void* event_data)
{
    httpd_handle_t* server = (httpd_handle_t*) arg;
    if (*server == NULL) {
        ESP_LOGI(TAG, "Starting webserver");
        *server = start_webserver();
    }
}

static void event_handler(void* arg, esp_event_base_t event_base,
                                int32_t event_id, void* event_data)
{
    if (event_base == WIFI_EVENT && event_id == WIFI_EVENT_STA_START) {
        esp_wifi_connect();
    } else if (event_base == WIFI_EVENT && event_id == WIFI_EVENT_STA_DISCONNECTED) {
        if (s_retry_num < WIFI_RETRIES) {
            esp_wifi_connect();
            s_retry_num++;
            ESP_LOGI(TAG, "retry to connect to the AP");
        } else {
            xEventGroupSetBits(s_wifi_event_group, WIFI_FAIL_BIT);
        }
        ESP_LOGI(TAG,"connect to the AP fail");
    } else if (event_base == IP_EVENT && event_id == IP_EVENT_STA_GOT_IP) {
        ip_event_got_ip_t* event = (ip_event_got_ip_t*) event_data;
        ESP_LOGI(TAG, "got ip:%s",
                 ip4addr_ntoa(&event->ip_info.ip));
        s_retry_num = 0;
        xEventGroupSetBits(s_wifi_event_group, WIFI_CONNECTED_BIT);
    }
}

void wifi_init_sta()
{
    s_wifi_event_group = xEventGroupCreate();

    tcpip_adapter_init();

    ESP_ERROR_CHECK(esp_event_loop_create_default());

    wifi_init_config_t cfg = WIFI_INIT_CONFIG_DEFAULT();
    ESP_ERROR_CHECK(esp_wifi_init(&cfg));

    //tcpip_adapter_dhcpc_stop(TCPIP_ADAPTER_IF_STA);
    //tcpip_adapter_ip_info_t info;
    //ip4_addr_t gw;
    //gw.addr = ipaddr_addr("192.168.0.1");
    //info.gw = gw;
    //ip4_addr_t ip;
    //ip.addr = ipaddr_addr("192.168.0.110");
    //info.ip = ip;
    //ip4_addr_t netmask;
    //netmask.addr = ipaddr_addr("255.255.255.0");
    //info.netmask = netmask;
    //tcpip_adapter_sta_start(0, &info);

    ESP_ERROR_CHECK(esp_event_handler_register(WIFI_EVENT, ESP_EVENT_ANY_ID, &event_handler, NULL));
    ESP_ERROR_CHECK(esp_event_handler_register(IP_EVENT, IP_EVENT_STA_GOT_IP, &event_handler, NULL));

    wifi_config_t wifi_config = {
        .sta = {
            .ssid = WIFI_SSID,
            .password = WIFI_PASS
        },
    };
    ESP_ERROR_CHECK(esp_wifi_set_mode(WIFI_MODE_STA) );
    ESP_ERROR_CHECK(esp_wifi_set_config(ESP_IF_WIFI_STA, &wifi_config) );
    ESP_ERROR_CHECK(esp_wifi_start() );

    ESP_LOGI(TAG, "wifi_init_sta finished.");

    /* Waiting until either the connection is established (WIFI_CONNECTED_BIT) or connection failed for the maximum
     * number of re-tries (WIFI_FAIL_BIT). The bits are set by event_handler() (see above) */
    EventBits_t bits = xEventGroupWaitBits(s_wifi_event_group,
            WIFI_CONNECTED_BIT | WIFI_FAIL_BIT,
            pdFALSE,
            pdFALSE,
            portMAX_DELAY);

    //tcpip_adapter_set_ip_info(TCPIP_ADAPTER_IF_STA, &info);
    /* xEventGroupWaitBits() returns the bits before the call returned, hence we can test which event actually
     * happened. */
    if (bits & WIFI_CONNECTED_BIT) {
        ESP_LOGI(TAG, "connected to ap SSID:%s password:%s",
        		WIFI_SSID, WIFI_PASS);
    } else if (bits & WIFI_FAIL_BIT) {
        ESP_LOGI(TAG, "Failed to connect to SSID:%s, password:%s",
        		WIFI_SSID, WIFI_PASS);
    } else {
        ESP_LOGE(TAG, "UNEXPECTED EVENT");
    }

    ESP_ERROR_CHECK(esp_event_handler_unregister(IP_EVENT, IP_EVENT_STA_GOT_IP, &event_handler));
    ESP_ERROR_CHECK(esp_event_handler_unregister(WIFI_EVENT, ESP_EVENT_ANY_ID, &event_handler));
    vEventGroupDelete(s_wifi_event_group);
}

void i2c_setup()
{
	printf("Setting up I�C driver on port 1... ");
	i2c_config_t config;
	config.mode = I2C_MODE_MASTER;
	config.sda_io_num = 33;
	config.sda_pullup_en = GPIO_PULLUP_ENABLE;
	config.scl_io_num = 32;
	config.scl_pullup_en = GPIO_PULLUP_ENABLE;
	config.master.clk_speed = 100000;
	i2c_param_config(I2C_NUM_0, &config);
	printf("Set driver parameters... ");
	esp_err_t err = i2c_driver_install(I2C_NUM_0, I2C_MODE_MASTER, 0, 0, 0);
	if (err == ESP_OK)
		printf("Driver installed!\n");
	else if (err == ESP_ERR_INVALID_ARG)
		printf("Driver install failed, invalid arguments!\n");
	else
		printf("Driver install failed!\n");
}

int8_t i2c_read(uint8_t dev_id, uint8_t reg_addr, uint8_t *data, uint16_t len) {
	i2c_cmd_handle_t cmd = i2c_cmd_link_create();
	i2c_master_start(cmd);
	i2c_master_write_byte(cmd, dev_id << 1 | I2C_MASTER_WRITE, 1);
	i2c_master_write_byte(cmd, reg_addr, 1);
	i2c_master_start(cmd);
	i2c_master_write_byte(cmd, dev_id << 1 | I2C_MASTER_READ, 1);
	if (len > 1) {
		i2c_master_read(cmd, data, len - 1, I2C_MASTER_ACK);
	}
	i2c_master_read_byte(cmd, data + len - 1, I2C_MASTER_NACK);
	i2c_master_stop(cmd);
	i2c_master_cmd_begin(I2C_NUM_0, cmd, 500 / portTICK_RATE_MS);
	i2c_cmd_link_delete(cmd);
	return 0;
}

int8_t i2c_write(uint8_t dev_id, uint8_t reg_addr, uint8_t *data, uint16_t len) {
	//printf("Writing to bus: dev_id=%x, reg_addr=%x, data=%p, length=%u\n", dev_id, reg_addr, data, len);
	i2c_cmd_handle_t cmd = i2c_cmd_link_create();
	i2c_master_start(cmd);
	i2c_master_write_byte(cmd, (dev_id << 1) | I2C_MASTER_WRITE, 1);
	i2c_master_write_byte(cmd, reg_addr, 1);
	i2c_master_write(cmd, data, len, 1);
	i2c_master_stop(cmd);
	i2c_master_cmd_begin(I2C_NUM_0, cmd, 500 / portTICK_RATE_MS);
	i2c_cmd_link_delete(cmd);
	return 0;
}

void i2c_delay(uint32_t period) {
	vTaskDelay(period / portTICK_PERIOD_MS);
}

void i2c_shutdown()
{
	printf("Shutting down I�C bus... ");
	esp_err_t err = i2c_driver_delete(I2C_NUM_0);
	if (err == ESP_ERR_INVALID_ARG)
		printf("Failed, invalid arguments!\n");
	else
		printf("Success!\n");
}

void read_sensor(struct bme280_dev* dev, int32_t* temp, uint32_t* pressure, uint32_t* humidity) {

	uint8_t settings_sel;
	uint32_t req_delay;
	struct bme280_data comp_data;

	dev->settings.osr_h = BME280_OVERSAMPLING_16X;
	dev->settings.osr_p = BME280_OVERSAMPLING_16X;
	dev->settings.osr_t = BME280_OVERSAMPLING_16X;
	dev->settings.filter = BME280_FILTER_COEFF_16;

	settings_sel = BME280_OSR_PRESS_SEL | BME280_OSR_TEMP_SEL | BME280_OSR_HUM_SEL | BME280_FILTER_SEL;
	bme280_set_sensor_settings(settings_sel, dev);

	req_delay = 12*bme280_cal_meas_delay(&(dev->settings));

	/* Continuously stream sensor data */
	bme280_set_sensor_mode(BME280_FORCED_MODE, dev);
	/* Wait for the measurement to complete and print data @25Hz */
	dev->delay_ms(req_delay / portTICK_PERIOD_MS);
	bme280_get_sensor_data(BME280_ALL, &comp_data, dev);
	*temp = comp_data.temperature;
	*pressure = comp_data.pressure;
	*humidity = comp_data.humidity;
}

void read_sensor2(struct bme280_dev* dev, int32_t* temp, uint32_t* pressure, uint32_t* humidity) {

	uint8_t settings_sel;
	uint32_t req_delay;
	struct bme280_data comp_data;

	dev->settings.osr_h = BME280_OVERSAMPLING_16X;
	dev->settings.osr_p = BME280_OVERSAMPLING_16X;
	dev->settings.osr_t = BME280_OVERSAMPLING_16X;
	dev->settings.filter = BME280_FILTER_COEFF_16;

	settings_sel = BME280_OSR_PRESS_SEL | BME280_OSR_TEMP_SEL | BME280_OSR_HUM_SEL | BME280_FILTER_SEL;
	bme280_set_sensor_settings(settings_sel, dev);
	/*Calculate the minimum delay required between consecutive measurement based upon the sensor enabled
		 *  and the oversampling configuration. */
	req_delay = 12*bme280_cal_meas_delay(&(dev->settings));

	bme280_set_sensor_mode(BME280_FORCED_MODE, dev);
	/* Wait for the measurement to complete and print data @25Hz */
	dev->delay_ms(req_delay / portTICK_PERIOD_MS);
	bme280_get_sensor_data(BME280_ALL, &comp_data, dev);
	*temp = comp_data.temperature;
	*pressure = comp_data.pressure;
	*humidity = comp_data.humidity;
}

void print_data(u8g2_t* u8g2, int32_t temp_raw, uint32_t pressure_raw, uint32_t humidity_raw,
		int32_t temp2_raw, uint32_t pressure2_raw, uint32_t humidity2_raw) {
	// Calc temperature pre and post comma values
	int32_t temp_pre = temp_raw / 100;
	int32_t temp_post = (abs(temp_raw) % 100) / 10;
	int32_t temp2_pre = temp2_raw / 100;
	int32_t temp2_post = (abs(temp2_raw) % 100) / 10;

	// Calc pressure values
	uint32_t press = pressure_raw / 100;
	uint32_t press2 = pressure2_raw / 100;

	// Calc humidity pre and post comma values
	uint32_t humid_pre = humidity_raw / 1024;
	uint32_t humid_post = (humidity_raw - humid_pre*1024) * 10 / 1024;
	uint32_t humid2_pre = humidity2_raw / 1024;
	uint32_t humid2_post = (humidity2_raw - humid2_pre*1024) * 10 / 1024;

	// Format temperatures
	char temp_str[2*(sizeof(int)*8+1)+5] = ""; // ""
	char temp_pre_str[sizeof(int)*8+1];
	itoa(temp_pre, temp_pre_str, 10);
	char temp_post_str[sizeof(int)*8+1];
	itoa(temp_post, temp_post_str, 10);
	char temp2_pre_str[sizeof(int)*8+1];
	itoa(temp2_pre, temp2_pre_str, 10);
	char temp2_post_str[sizeof(int)*8+1];
	itoa(temp2_post, temp2_post_str, 10);
	if (temp_pre < 10)
		strcat(temp_str, " "); // Add space if first temperatur is just one digit long " "
	strcat(temp_str, temp_pre_str); // " 1"
	strcat(temp_str, ","); // " 1,"
	strcat(temp_str, temp_post_str); // " 1,3"
	strcat(temp_str, " "); // " 1,3 "
	if (temp2_pre >= 0)
		strcat(temp_str, " "); // Add space if there is no minus sign " 1,3  "
	if (temp2_pre < 10)
		strcat(temp_str, " "); // Add space if second temperatur is just one digit long " 1,3   "
	strcat(temp_str, temp2_pre_str); // " 1,3   7"
	strcat(temp_str, ","); // " 1,3   7,"
	strcat(temp_str, temp2_post_str); // " 1,3   7,2"
	strcat(temp_str, "  �C"); // " 1,3   7,2  �C"

	// Format temperatures
	char humid_str[2*(sizeof(int)*8+1)+5] = ""; // ""
	char humid_pre_str[sizeof(int)*8+1];
	itoa(humid_pre, humid_pre_str, 10);
	char humid_post_str[sizeof(int)*8+1];
	itoa(humid_post, humid_post_str, 10);
	char humid2_pre_str[sizeof(int)*8+1];
	itoa(humid2_pre, humid2_pre_str, 10);
	char humid2_post_str[sizeof(int)*8+1];
	itoa(humid2_post, humid2_post_str, 10);
	strcat(humid_str, humid_pre_str); // "12"
	strcat(humid_str, ","); // "12,"
	strcat(humid_str, humid_post_str); // "12,5"
	strcat(humid_str, "  "); // "12,5  "
	strcat(humid_str, humid2_pre_str); // "12,5  45"
	strcat(humid_str, ","); // "12,5  45,"
	strcat(humid_str, humid2_post_str); // "12,5  45,23"
	strcat(humid_str, "   %"); // "12,5  45,23   %"

	// Format pressure
	char pressure_str[2*(sizeof(int)*8+1)+5] = ""; // ""
	char press1_str[sizeof(int)*8+1];
	itoa(press, press1_str, 10);
	char press2_str[sizeof(int)*8+1];
	itoa(press2, press2_str, 10);
	if (press < 1000)
		strcat(pressure_str, " ");
	strcat(pressure_str, press1_str);
	strcat(pressure_str, "  ");
	if (press2 < 1000)
		strcat(pressure_str, " ");
	strcat(pressure_str, press2_str);
	strcat(pressure_str, " hPa");

	u8g2_ClearBuffer(u8g2);
	u8g2_SetFont(u8g2, u8g2_font_profont17_mf);
	int8_t fontheight = u8g2_GetAscent(u8g2);
	int8_t fontmargin = abs(u8g2_GetDescent(u8g2))+2;
	u8g2_DrawStr(u8g2, 0, fontheight, " IN    OUT   ");
	u8g2_DrawStr(u8g2, 0, 2*fontheight + fontmargin, temp_str);
	u8g2_DrawStr(u8g2, 0, 3*fontheight + 2*fontmargin, humid_str);
	u8g2_DrawStr(u8g2, 0, 4*fontheight + 3*fontmargin, pressure_str);
	u8g2_SendBuffer(u8g2);
}

void app_main(void)
{
	int32_t temp = 0;
	uint32_t pressure = 0;
	uint32_t humidity = 0;
	int32_t temp2 = 0;
	uint32_t pressure2 = 0;
	uint32_t humidity2 = 0;

	// INIT SENSOR
	i2c_setup();
	struct bme280_dev dev;
	dev.dev_id = 0x76;
	dev.intf = BME280_I2C_INTF;
	dev.read = i2c_read;
	dev.write = i2c_write;
	dev.delay_ms = i2c_delay;
	bme280_init(&dev);

	// INIT SENSOR2
	struct bme280_dev dev2;
	dev2.dev_id = 0x77;
	dev2.intf = BME280_I2C_INTF;
	dev2.read = i2c_read;
	dev2.write = i2c_write;
	dev2.delay_ms = i2c_delay;
	bme280_init(&dev2);

	// INIT DISPLAY
	u8g2_esp32_hal_t u8g2_esp32_hal = U8G2_ESP32_HAL_DEFAULT;
	u8g2_esp32_hal.sda   = 18;
	u8g2_esp32_hal.scl  = 19;

	u8g2_esp32_hal_init(u8g2_esp32_hal);
	u8g2_t u8g2;
	u8g2_Setup_ssd1306_i2c_128x64_vcomh0_f(&u8g2, U8G2_R0, u8g2_esp32_i2c_byte_cb,
		u8g2_esp32_gpio_and_delay_cb);
	u8x8_SetI2CAddress(&u8g2.u8x8,0x3C << 1);
	u8g2_InitDisplay(&u8g2); // send init sequence to the display, display is in sleep mode after this,
	u8g2_SetPowerSave(&u8g2, 0); // wake up display

	// INIT WIFI
	//Initialize NVS
	esp_err_t ret = nvs_flash_init();
	if (ret == ESP_ERR_NVS_NO_FREE_PAGES || ret == ESP_ERR_NVS_NEW_VERSION_FOUND) {
	  ESP_ERROR_CHECK(nvs_flash_erase());
	  ret = nvs_flash_init();
	}
	ESP_ERROR_CHECK(ret);

	ESP_LOGI(TAG, "ESP_WIFI_MODE_STA");
	wifi_init_sta();

	// INIT WEBSERVER
	static httpd_handle_t server = NULL;
	ESP_ERROR_CHECK(esp_event_handler_register(IP_EVENT, IP_EVENT_STA_GOT_IP, &connect_handler, &server));
	ESP_ERROR_CHECK(esp_event_handler_register(WIFI_EVENT, WIFI_EVENT_STA_DISCONNECTED, &disconnect_handler, &server));
	server = start_webserver();

	while (1) {
		read_sensor(&dev, &temp, &pressure, &humidity);
		read_sensor(&dev2, &temp2, &pressure2, &humidity2);
		printf("%i �c, %i hPa, %i %%\r\n", temp, pressure, humidity);
		printf("%i �c, %i hPa, %i %%\r\n", temp2, pressure2, humidity2);
		print_data(&u8g2, temp, pressure, humidity, temp2, pressure2, humidity2);
		vTaskDelay(250 / portTICK_PERIOD_MS);
	}
}