#include <stdio.h>
#include <stdlib.h>
#include <time.h>

typedef struct Song {
	int* id;
	char* name;
	char* artist;
	struct Song* next;
}Song;

Song* createSong(int id, char* name, char* artist);
void printSongDetails(Song* song);
void freeSong(Song* song);
void addSongToTheEndOfTheList(Song* head, Song* songToAdd);
void printPlaylist(Song* head);
void freePlaylist(Song* head);
void removeSong(Song* head, Song* songToRemove);
int countList(Song* head);
void swapSong(Song* head, Song* Source, int id);
void shuffleList(Song* head);

void main() {
	Song* head = createSong(1, "aaaa", "aaaa");
	Song* song2 = createSong(2, "bbbb", "bbbb");
	Song* song3 = createSong(3, "cccc", "cccc");
	addSongToTheEndOfTheList(head, song2);
	addSongToTheEndOfTheList(head, song3);
	printPlaylist(head);
	shuffleList(head);
	printPlaylist(head);
	//freePlaylist(head);
}

Song* createSong(int id, char* name, char* artist) {
	Song* newSong = (Song*)malloc(sizeof(Song));
	if (newSong) {
		newSong->id = id;
		newSong->name = name;
		newSong->artist = artist;
		newSong->next = NULL;
		//printf("Created New Song\n");
		//printSongDetails(newSong);
	}
	else {
		printf("Could not allocate memory\n");
		exit(1);
	}
	return newSong;
}

void printSongDetails(Song* song) {
	//Song name: hdfhfhd, Artist: hdfhdb
	printf("Song name: %s, Artist name: %s\n",song->name,song->artist);
}

void freeSong(Song* song) {
	free(song);
}

void addSongToTheEndOfTheList(Song* head, Song* songToAdd) {
	Song* currentSong = head;
	if (currentSong) {
		while (currentSong->next) {
			currentSong = currentSong->next;
		}
		currentSong->next = songToAdd;
		songToAdd->next = NULL;
	}
	else {
		printf("List is empty!\n");
	}
}

void printPlaylist(Song* head) {
	Song* currentSong = head;
	if (currentSong)
	{
		printf("The playlist: \n");
		for (int i = 1; currentSong; i++)
		{
			printf("%d. ", i);
			printSongDetails(currentSong);
			currentSong = currentSong->next;
		}
	}
	else
	{
		printf("The playlist is empty!\n");
	}
}


void freePlaylist(Song* head) {
	Song* currentSong = head;
	Song* temp;
	if (head) {
		while (currentSong)
		{
			temp = currentSong->next;
			freeSong(currentSong);
			currentSong = temp;
		}
		printf("The playlist has been emptied");
	}
	else {
		printf("The list is already empty.");
	}
}

void removeSong(Song* head, Song* songToRemove) {
	printf("Removing song: ");
	printSongDetails(songToRemove);
	Song* currentSong = head;
	Song* nextSong = songToRemove->next;
	while (currentSong && currentSong->next != songToRemove) {
		currentSong = currentSong->next;
	}
	if (currentSong) {
		freeSong(songToRemove);
		currentSong->next = nextSong;
	}
	else {
		printf("The requested song is not in the list");
	}
}
int countList(Song* head) {
	Song* currentSong = head;
	int i = 0;
	if (currentSong)
	{
		while (currentSong->next)
		{
			currentSong = currentSong->next;
			i++;
		}
		i++;
	}
	return i;
}
void swapSong(Song* head,Song* Source, int id) {
	Song* tempSong = (Song*)malloc(sizeof(Song));
	Song* currentSong = head;
	while(currentSong && currentSong->id != id){
		currentSong = currentSong->next;
	}
	if (currentSong) {
		tempSong->id = currentSong->id;
		tempSong->name = currentSong->name;
		tempSong->artist = currentSong->artist;
		tempSong->next = currentSong->next;
		currentSong->id = Source->id;
		currentSong->name = Source->name;
		currentSong->artist = Source->artist;
		currentSong->next = Source->next;
		Source->id = tempSong->id;
		Source->name = tempSong->name;
		Source->artist = tempSong->artist;
		Source->next = tempSong->next;
		free(tempSong);
	}
	else {
		printf("The list is empty.");
	}

}
void shuffleList(Song* head) {
	Song* currentSong = head;
	int listLength = countList(head);
	int randNum;
	srand(time(NULL));
	if (currentSong) {
		for (int i = 1; currentSong;i++) {
			swapSong(head, currentSong, rand()%listLength+1);
			currentSong = currentSong->next;
		}
	}
	else {
		printf("The list is empty.");
	}
}