#include "node.h"

#include

using namespace std;

class LinkedList {

node* head;

node* tail;

int size;

node* playing = NULL;

 void appendNode(node *prev, node *n) { 

 n->next = prev->next; 

 prev->next = n;

 n->prev = prev;

 n->next->prev = n; }

public: LinkedList() {

head = new node;

tail = new node;

head->song = NULL;

tail->song = NULL;

head->next = tail;

tail->prev = head;

size = 0; }

void addSong(Song* s) { 

node *n = new node; 

n->song = s; 

if (s->fave) { 

node *cur = head->next; 

while (cur != tail && cur->song->fave) { 

cur = cur->next; } 

appendNode(cur->prev, n); 

} else { 

appendNode(tail->prev, n); } 

size++; }

Song* next() { 

if (playing && playing->next != tail) { 

playing = playing->next; 

playing->song->play(); 

return playing->song; } 

if (!playing && size && head->next != tail) { 

playing = head->next; 

playing->song->play(); 

return playing->song; } 

return NULL; }

bool toggleFavorite() { 

if (playing) { 

playing->song->fave = !playing->song->fave; 

return playing->song->fave; } 

return false; }

Song* previous() { 

if (playing && playing->prev != head) { 

playing = playing->prev; 

playing->song->play(); 

return playing->song; } 

return NULL; }

Song* play() { 

if (playing) { 

playing->song->play(); 

return playing->song; } 

return NULL; }

Song* skip() { 

if (playing) { 

playing->song->skip(); 

if (playing->next != tail) { 

playing->song->skip(); 

playing = playing->next; 

playing->song->play(); 

return playing->song; } } 

return NULL; }

Song* skip(int item) { 

if (!playing) return NULL; 

playing->song->skip(); 

node *n = playing; 

for (int i = 0; i < item && n != tail; i++) { 

n = n->next; } 

if (n != tail) { 

playing = n; 

playing->song->play(); 

return n->song; } 

return NULL; }

Song* find(string art) { 

node *cur = playing ? playing->next : head->next; while (cur != tail) { 

if (cur->song->artist[0] == art || cur->song->artist[1] == art) { 

playing = cur; 

cur->song->play(); 

return cur->song; 

} 

cur = cur->next; 

}

return NULL; }

Song* remove() { 

if (playing) { 

size--; 

Song *ret = playing->song; 

node *n = playing; 

playing->prev->next = playing->next; 

playing->next->prev = playing->prev; 

if (playing->next != tail) { 

playing = playing->next; 

} else if (playing->prev != head) { 

playing = playing->prev; 

} else { 

playing = NULL; 

} 

delete n; 

return ret; 

} 

return NULL; }

void print() {

cout << "Song Count: " << size << endl;

node* c = head->next;

int i = 1;

while (c != tail) {

cout << i++ << ". "; c->song->print(); cout << endl; c = c->next;

}

}

};