#include "lwip/apps/httpd.h"
#include "pico/cyw43_arch.h"
#include "hardware/adc.h"

// SSI tags - tag length limited to 8 bytes by default
const char * ssi_tags[] = {"volt","temp","led"};

u16_t ssi_handler(int iIndex, char *pcInsert, int iInsertLen) {
	size_t printed;
	switch (iIndex) {
	case 0: // volt
		{
		const float voltage = adc_read() * 3.3f / (1 << 12);
		printed = snprintf(pcInsert, iInsertLen, "%f", voltage);
		}
		break;
	case 1: // temp
		{
		const float voltage = adc_read() * 3.3f / (1 << 12);
		const float tempC = 27.0f - (voltage - 0.706f) / 0.001721f;
		printed = snprintf(pcInsert, iInsertLen, "%f", tempC);
		}
		break;
	case 2: // led
		{
		bool led_status = cyw43_arch_gpio_get(CYW43_WL_GPIO_LED_PIN);
		if(led_status == true){
			printed = snprintf(pcInsert, iInsertLen, "ON");
		}
		else{
			printed = snprintf(pcInsert, iInsertLen, "OFF");
		}
		}
		break;
	default:
		printed = 0;
		break;
	}

	return (u16_t)printed;
}

// Initialise the SSI handler
void ssi_init() {
	// Initialise ADC (internal pin)
	adc_init();
	adc_set_temp_sensor_enabled(true);
	adc_select_input(4);

	http_set_ssi_handler(ssi_handler, ssi_tags, LWIP_ARRAYSIZE(ssi_tags));
}