#ifndef COMMS_H_
#define COMMS_H_

#include <avr/io.h>
#include <string.h>


/**
 * Our format goes like this:
 * 
 * 1 byte command, with data after
 */


typedef enum {
    COMMS_CMD_CLR = 0U,         //! Clears LCD and all file names
    COMMS_CMD_NUM,              //! sends the total number of songs to choose from
	COMMS_CMD_QUERY_NUM,
    COMMS_CMD_QUERY_NAME,       //! Queries for the name of a given song ID
    COMMS_CMD_REPLY_NAME,       //! Responds with the name of the given song ID
    COMMS_CMD_SELECT_FILE,      //! selects a file from the given list to play, data is 1 byte for id
    COMMS_CMD_PLAY,             //! Starts playing file
    COMMS_CMD_PAUSE             //! pauses playing file
} comms_cmd_t;

/** @brief Inline function to send commands and values.
 */
inline void comms_send(comms_cmd_t cmd) {

    while (! (UCSR0A & (1 << UDRE0)));
    UDR0 = cmd;
}

/** @brief Selects a file from the list on the DAC side.
 * 
 * If another song is playing, this will stop
 * that song from playing and select the new one.
 */
inline void comms_select_file(uint8_t id) {
    comms_send(COMMS_CMD_SELECT_FILE);
    comms_send((comms_cmd_t) id);
}

/** @brief Queries for the name of the given song ID.
 */
inline void comms_query_name(uint8_t id) {
    comms_send(COMMS_CMD_QUERY_NAME);
    comms_send(id);
}

/** @brief Repliers with the name of the requsted song ID
 */
inline void comms_reply_name(char* name) {
    uint8_t len = strlen(name);
    comms_send(COMMS_CMD_REPLY_NAME);
    comms_send(len);

    for (uint8_t i = 0; i < len; i++) {
        comms_send((uint8_t) name[i]);
    }
}

/** @brief Clears the LCD list of files.
 */
inline void comms_clear() {
    comms_send(COMMS_CMD_CLR);
}

/** @brief Starts playing song.
 */
inline void comms_play() {
    comms_send(COMMS_CMD_PLAY);
}

/** @brief Pauses playing song.
 */
inline void comms_pause() {
    comms_send(COMMS_CMD_PLAY);
}

#endif