/**
 * @file keyboard.h
 * @brief PS/2 keyboard driver.
 *
 * Handles IRQ1 keyboard interrupts, translates scancodes to ASCII,
 * and provides a ring buffer for user-space reading via SYS_READ.
 */

#ifndef KEYBOARD_H
#define KEYBOARD_H

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

/** Keyboard input buffer size. */
#define KB_BUFFER_SIZE 256

/**
 * Initialize the keyboard driver.
 */
void keyboard_init(void);

/**
 * Handle a keyboard IRQ (called from isr_handler for IRQ1).
 *
 * @param regs Register state (may be used to wake blocked processes).
 */
void keyboard_irq(registers_t *regs);

/**
 * Read characters from the keyboard buffer.
 * Non-blocking: returns whatever is available, 0 if empty.
 *
 * @param buf   Destination buffer.
 * @param count Maximum bytes to read.
 * @return Number of bytes read.
 */
uint32_t keyboard_read(char *buf, uint32_t count);

/**
 * Check if there is data available in the keyboard buffer.
 *
 * @return Non-zero if data is available.
 */
int keyboard_has_data(void);

/**
 * Block the given process until keyboard data is available.
 * Sets the process to BLOCKED state and records it as waiting for keyboard.
 * When data arrives, the process will be unblocked.
 *
 * @param regs Current interrupt frame (for saving process state).
 */
void keyboard_block_for_input(registers_t *regs);

#endif /* KEYBOARD_H */