#include <stdio.h>          //provides printf function
#include <string.h>         //provides memset etc


#include "pico/stdlib.h"    //provides standard library for the pico
#include "hardware/gpio.h"  //configure gpio
#include "hardware/i2c.h"   //configure i2c

#include "shtc3.h"
#include "ssd1306.h"
#include "raspberry26x32.h"

#define I2C_INSTANCE i2c0
#define PICO_I2C_SDA_PIN 16
#define PICO_I2C_SCL_PIN 17

// I2C peripheral adapted from https://wokwi.com/projects/333375908055351891

// I2C reserves some addresses for special purposes. We exclude these from the scan.
// These are any addresses of the form 000 0xxx or 111 1xxx
bool reserved_addr(uint8_t addr) {
  return (addr & 0x78) == 0 || (addr & 0x78) == 0x78;
}

int main()
{
  stdio_init_all();

  // This example will use I2C0 on the selected SDA and SCL pins
  i2c_init(I2C_INSTANCE, 100 * 1000);
  gpio_set_function(PICO_I2C_SDA_PIN, GPIO_FUNC_I2C);
  gpio_set_function(PICO_I2C_SCL_PIN, GPIO_FUNC_I2C);

  //the pico has a board with hardware pullups attached
  //gpio_pull_up(PICO_I2C_SDA_PIN);
  //gpio_pull_up(PICO_I2C_SCL_PIN);

  printf("   0  1  2  3  4  5  6  7  8  9  A  B  C  D  E  F\n");
  for (int addr = 0; addr < (1 << 7); ++addr) {
    if (addr % 16 == 0) {
      printf("%02x ", addr);
    }

    // Perform a 1-byte dummy read from the probe address. If a slave
    // acknowledges this address, the function returns the number of bytes
    // transferred. If the address byte is ignored, the function returns
    // -1.

    // Skip over any reserved addresses.
    int ret;
    uint8_t rxdata;
    if (reserved_addr(addr))
      ret = PICO_ERROR_GENERIC;
    else
      ret = i2c_read_blocking(I2C_INSTANCE, addr, &rxdata, 1, false);

    printf(ret < 0 ? "." : "@");
    printf(addr % 16 == 15 ? "\n" : "  ");
  }
  printf("\n");

  // Initialize render area for entire frame (SSD1306_WIDTH pixels by SSD1306_NUM_PAGES pages)
  struct render_area frame_area = {
    start_col: 0,
    end_col : SSD1306_WIDTH - 1,
    start_page : 0,
    end_page : SSD1306_NUM_PAGES - 1
  };

  calc_render_area_buflen(&frame_area);
  // zero the entire display
  uint8_t buf[SSD1306_BUF_LEN];
  memset(buf, 0, SSD1306_BUF_LEN);
  render(buf, &frame_area);

  // intro sequence: flash the screen 3 times
  for (int i = 0; i < 3; i++) {
    SSD1306_send_cmd(SSD1306_SET_ALL_ON);    // Set all pixels on
    sleep_ms(500);
    SSD1306_send_cmd(SSD1306_SET_ENTIRE_ON); // go back to following RAM for pixel state
    sleep_ms(500);
  }

    // render 3 cute little raspberries
    struct render_area area = {
        start_page : 0,
        end_page : (IMG_HEIGHT / SSD1306_PAGE_HEIGHT)  - 1
    };
    area.start_col = 0;
    area.end_col = IMG_WIDTH - 1;

    calc_render_area_buflen(&area);

    uint8_t offset = 5 + IMG_WIDTH; // 5px padding

    for (int i = 0; i < 3; i++) {
        render(raspberry26x32, &area);
        area.start_col += offset;
        area.end_col += offset;
    }

  while (true) {
    uint16_t sht3c_id = shtc3_read_id();
    uint32_t res;
    float temp, hum;
    printf("Read SHT3C chip ID: %x\n", sht3c_id);

    res = shtc3_perform_measurements(&temp, &hum);
    printf("Read SHT3C I2C read res: %x\n", res);
    printf("Temperature: %.1f\n", temp);
    printf("Humidity: %.1f\n", hum);
    sleep_ms(1000);
  }
}