#include <stdio.h>
#include <string.h>
#include <malloc.h>
#include "peer.h"
#include "message.h"
#include "bitfield.h"

extern Bitmap *bitmap;

// 指向當前與之進行通信的peer列表
Peer *peer_head = NULL;

int  initialize_peer(Peer *peer)
{
	if(peer == NULL)   return -1;

	peer->socket = -1;
	memset(peer->ip,0,16);
	peer->port = 0;
	memset(peer->id,0,21);
	peer->state = INITIAL;

	peer->in_buff      = NULL;
	peer->out_msg      = NULL;
	peer->out_msg_copy = NULL;

	peer->in_buff = (char *)malloc(MSG_SIZE);
	if(peer->in_buff == NULL)  goto OUT;
	memset(peer->in_buff,0,MSG_SIZE);
	peer->buff_len = 0;

	peer->out_msg = (char *)malloc(MSG_SIZE);
	if(peer->out_msg == NULL)  goto OUT;
	memset(peer->out_msg,0,MSG_SIZE);
	peer->msg_len  = 0;
	
	peer->out_msg_copy = (char *)malloc(MSG_SIZE);
	if(peer->out_msg_copy == NULL)  goto OUT;
	memset(peer->out_msg_copy,0,MSG_SIZE);
	peer->msg_copy_len   = 0;
	peer->msg_copy_index = 0;

	peer->am_choking      = 1;
	peer->am_interested   = 0;
	peer->peer_choking    = 1;
	peer->peer_interested = 0;
	
	peer->bitmap.bitfield        = NULL;
	peer->bitmap.bitfield_length = 0;
	peer->bitmap.valid_length    = 0;
	
	peer->Request_piece_head     = NULL;
	peer->Requested_piece_head   = NULL;
	
	peer->down_total = 0;
	peer->up_total   = 0;
	
	peer->start_timestamp     = 0;
	peer->recet_timestamp     = 0;
	
	peer->last_down_timestamp = 0;
	peer->last_up_timestamp   = 0;
	peer->down_count          = 0;
	peer->up_count            = 0;
	peer->down_rate           = 0.0;
	peer->up_rate             = 0.0;
	
	peer->next = (Peer *)0;
	return 0;

OUT:
	if(peer->in_buff != NULL)      free(peer->in_buff);
	if(peer->out_msg != NULL)      free(peer->out_msg);
	if(peer->out_msg_copy != NULL) free(peer->out_msg_copy);
	return -1;
}

Peer* add_peer_node()
{
	int  ret;
	Peer *node, *p;

	// 分配內存空間
	node = (Peer *)malloc(sizeof(Peer));
	if(node == NULL)  { 
		printf("%s:%d error\n",__FILE__,__LINE__); 
		return NULL;
	}

	// 進行初始化
	ret = initialize_peer(node);
	if(ret < 0) { 
		printf("%s:%d error\n",__FILE__,__LINE__);
		free(node);
		return NULL;
	}

	// 將node加入到peer鏈表中
	if(peer_head == NULL)  { peer_head = node; }
	else {
		p = peer_head;
		while(p->next != NULL)  p = p->next;
		p->next = node;
	}

	return node;
}

int del_peer_node(Peer *peer)
{
	Peer *p = peer_head, *q;

	if(peer == NULL)  return -1;

	while(p != NULL) {
		if( p == peer ) {
			if(p == peer_head)  peer_head = p->next;
			else  q->next = p->next;
			free_peer_node(p);  // 可能存在問題
			return 0;
		} else {
			q = p;
			p = p->next;
		}
	}

	return -1;
}

// 撤消當前請求隊列
int cancel_request_list(Peer *node)
{
	Request_piece  *p;

	p = node->Request_piece_head;
	while(p != NULL) {
		node->Request_piece_head = node->Request_piece_head->next;
		free(p);
		p = node->Request_piece_head;
	}

	return 0;
}

// 撤消當前被請求隊列
int cancel_requested_list(Peer *node)
{
	Request_piece  *p;
	
	p = node->Requested_piece_head;
	while(p != NULL) {
		node->Requested_piece_head = node->Requested_piece_head->next;
		free(p);
		p = node->Requested_piece_head;
	}
	
	return 0;
}

void  free_peer_node(Peer *node)
{
	if(node == NULL)  return;
	if(node->bitmap.bitfield != NULL) {
		free(node->bitmap.bitfield);
		node->bitmap.bitfield = NULL;
	}
	if(node->in_buff != NULL) {
		free(node->in_buff); 
		node->in_buff = NULL;
	}
	if(node->out_msg != NULL) {
		free(node->out_msg);
		node->out_msg = NULL;
	}
	if(node->out_msg_copy != NULL) {
		free(node->out_msg_copy);
		node->out_msg_copy = NULL;
	}

	cancel_request_list(node);
	cancel_requested_list(node);

	// 釋放完peer成員的內存后,再釋放peer所占的內存
	free(node);
}

void  release_memory_in_peer()
{
	Peer *p;

	if(peer_head == NULL)  return;

	p = peer_head;
	while(p != NULL) {
		peer_head = peer_head->next;
		free_peer_node(p);
		p = peer_head;
	}
}

void print_peers_data()
{
	Peer *p    = peer_head;
	int  index = 0;

	while(p != NULL) {
		printf("peer: %d  down_rate: %.2f \n", index, p->down_rate);

		index++;
		p = p->next;
	}
}