/**
 * @file oled.h
 * @brief SSD1315 OLED 128x64 I2C driver
 */
#pragma once

#include <stdint.h>
#include "esp_err.h"

#ifdef __cplusplus
extern "C" {
#endif

/* Screen dimensions */
#define OLED_WIDTH      128
#define OLED_HEIGHT     64
#define OLED_PAGES      8

/* OLED colors */
#define OLED_COLOR_BLACK   0
#define OLED_COLOR_WHITE   1
#define OLED_COLOR_YELLOW  2  /* Top 16px */
#define OLED_COLOR_BLUE    3  /* Bottom 48px */

/* Initialize OLED */
esp_err_t oled_init(int sda, int scl);

/* Clear entire display */
void oled_clear(void);

/* Clear specific area */
void oled_clear_area(uint8_t x, uint8_t y, uint8_t w, uint8_t h);

/* Set pixel at (x, y) */
void oled_draw_pixel(uint8_t x, uint8_t y, uint8_t color);

/* Draw character at (x, y) using 8x16 font */
void oled_draw_char(uint8_t x, uint8_t y, char c, uint8_t color);

/* Draw string at (x, y) */
void oled_draw_string(uint8_t x, uint8_t y, const char *str, uint8_t color);

/* Draw string in top yellow area (16px high) */
void oled_draw_top_string(const char *str, uint8_t color);

/* Draw horizontal line */
void oled_draw_hline(uint8_t x, uint8_t y, uint8_t w, uint8_t color);

/* Draw vertical line */
void oled_draw_vline(uint8_t x, uint8_t y, uint8_t h, uint8_t color);

/* Fill rectangle */
void oled_fill_rect(uint8_t x, uint8_t y, uint8_t w, uint8_t h, uint8_t color);

/* Update display (flush buffer to OLED) */
void oled_update(void);

/* Turn display on/off */
void oled_display_on(void);
void oled_display_off(void);

/* Set contrast */
void oled_set_contrast(uint8_t value);

#ifdef __cplusplus
}
#endif