X-Git-Url: https://git.llucax.com/z.facultad/75.52/treemulator.git/blobdiff_plain/c03f170abe6adaa72ff04318cb178cdcfb635f19..828f81aa63714ca38457a87ec77e77da72cd82b9:/src/btree.cpp

diff --git a/src/btree.cpp b/src/btree.cpp
index 8803d20..fc0a5e9 100644
--- a/src/btree.cpp
+++ b/src/btree.cpp
@@ -6,7 +6,7 @@ BTree::BTree (const std::string &name, unsigned int block_size, bool create_new_
 	uchar *node;
 	BTreeNodeHeader nh;
 
-	fp = fopen (name.c_str(), "wb");
+	fp = fopen (name.c_str(), "wb+");
 	if (!fp) {
 		/* TODO : mandar una exception ? */
 		return;
@@ -17,7 +17,7 @@ BTree::BTree (const std::string &name, unsigned int block_size, bool create_new_
 	
 	/* Inicializo el header */
 	header.block_size = block_size;
-	write_tree_header ();
+	WriteFileHeader ();
 
 	/* Creo el primer bloque vacio */
 	node = new uchar[block_size];
@@ -26,7 +26,7 @@ BTree::BTree (const std::string &name, unsigned int block_size, bool create_new_
 	nh.free_space = block_size - sizeof (BTreeNodeHeader);
 	nh.item_count = 0;
 	WriteNodoHeader (node, &nh);
-	write_block (node, 0);
+	WriteBlock (node, 0);
 
 	delete [] node;
 }
@@ -36,13 +36,13 @@ BTree::~BTree ()
 	fclose (fp);
 }
 
-void BTree::write_tree_header ()
+void BTree::WriteFileHeader ()
 {
 	fseek (fp, 0L, SEEK_SET);
 	fwrite (&header, 1, sizeof (BTreeFileHeader), fp);
 }
 
-void BTree::write_block (uchar *block, uint num)
+void BTree::WriteBlock (uchar *block, uint num)
 {
 	fseek (fp, num*header.block_size + sizeof (BTreeFileHeader), SEEK_SET);
 	fwrite (block, 1, header.block_size, fp);
@@ -50,28 +50,61 @@ void BTree::write_block (uchar *block, uint num)
 
 void BTree::AddKey (const Clave &k)
 {
-	std::list<Clave *> node_keys;
+	AddKeyR (&k, 0);
+}
+
+Clave* BTree::AddKeyR (const Clave *k, uint node_num)
+{
+	Clave *kout = NULL;
+	std::list<BTreeData> node_keys;
 
 	/* Leo el nodo raiz para empezar a agregar */
-	uchar *root = ReadBlock (0);
-	BTreeNodeHeader root_header;
-	ReadNodoHeader (root, &root_header);
+	uchar *node = ReadBlock (node_num);
+	BTreeNodeHeader node_header;
+	ReadNodoHeader (node, &node_header);
 
-	node_keys = ReadKeys (root, root_header);
-	std::cout << node_keys.size () << std::endl;
-	
-	if (root_header.free_space >= k.Size ()) {
-		std::cout << "Hay lugar para meter la clave" << std::endl;
-	} else {
-		std::cout << "__NO__ hay lugar para meter la clave" << std::endl;
+	if (node_header.level != 0) {
+		/* No estoy en una hoja, asi que tengo que buscar
+		 * para donde moverme para agregar la clave
+		 */
+		/* TODO :) */
 	}
 
-	
-	WriteKeys (root, root_header, node_keys);
-	WriteNodoHeader (root, &root_header);
-	write_block (root, 0);
 
-	delete [] root;
+	/* Estoy en una hoja, veo si lo puedo agregar */
+	BTreeLeafData data (k->Clone ());
+
+	if (node_header.free_space > data.Size ()) {
+		/* TODO : Insertar ordenado */
+		BTreeData datait;
+
+		node_keys = ReadKeys (node, node_header);
+		std::list<BTreeData>::iterator it = node_keys.begin ();
+
+		while (it != node_keys.end ()) {
+			datait = (*it);
+			if (data < datait)
+				/* Me pase, lo agrego aca! */
+				break;
+		}
+		node_keys.insert (it, data);
+		WriteKeys (node, node_header, node_keys);
+		WriteNodoHeader (node, &node_header);
+		WriteBlock (node, node_num);
+
+		PrintNode (node_num);
+	} else {
+		/* Split */
+		/* Lo que debe pasar :
+		 *  1) Separar N/2 claves en "nodo"
+		 *  2) Separar N/2-1 claves en un nuevo nodo
+		 *  3) kout = clave del medio y mandarla al padre
+		 */
+		std::cout << "SPLIT" << std::endl;
+		delete [] node;
+	}
+
+	return kout;
 }
 
 void BTree::DelKey (const Clave &k) {}
@@ -96,9 +129,9 @@ uchar *BTree::ReadBlock (uint num)
 	return out;
 }
 
-std::list<Clave *> BTree::ReadKeys (uchar *node, BTreeNodeHeader &node_header)
+std::list<BTreeData> BTree::ReadKeys (uchar *node, BTreeNodeHeader &node_header)
 {
-	std::list<Clave *> keys;
+	std::list<BTreeData> keys;
 	node += sizeof (BTreeNodeHeader);
 
 	for (uint i=0; i<node_header.item_count; i++) {
@@ -106,26 +139,56 @@ std::list<Clave *> BTree::ReadKeys (uchar *node, BTreeNodeHeader &node_header)
 		 * dependiendo de algun dato en el header del
 		 * arbol
 		 */
-		ClaveFija *k = new ClaveFija (node);
-		node += k->Size ();
-		keys.push_back (k);
+		/* TODO : Detectar si estoy en una hoja */
+		BTreeData data;
+		if (node_header.level == 0)
+			data = BTreeLeafData (node);
+		else
+			data = BTreeData (node);
+		node += data.Size ();
+		keys.push_back (data);
 	}
 
 	return keys;
 }
 
-void BTree::WriteKeys (uchar *node, BTreeNodeHeader &node_header, std::list<Clave *> &keys)
+void BTree::WriteKeys (uchar *node, BTreeNodeHeader &node_header, std::list<BTreeData> &keys)
 {
-	std::list<Clave *>::iterator it = keys.begin ();
+	std::list<BTreeData>::iterator it = keys.begin ();
 
 	node += sizeof (BTreeNodeHeader);
 
+	node_header.item_count = 0;
+	node_header.free_space = header.block_size - sizeof (BTreeNodeHeader);
+
 	while (it != keys.end ()) {
-		Clave *c = (*it);
-		memcpy (node, c->ToArray(), c->Size ());
-		node += c->Size ();
+		BTreeData d = (*it);
+		memcpy (node, d.ToArray(), d.Size ());
+		node += d.Size ();
+		node_header.free_space -= d.Size ();
+		node_header.item_count++;
 		it++;
 	}
 
 	/* TODO : incrementar node_header.item_count aca o fuera de este metodo? */
 }
+		
+void BTree::PrintNode (uint num)
+{
+	uchar *node = ReadBlock (num);
+	BTreeNodeHeader node_header;
+	ReadNodoHeader (node, &node_header);
+		
+	std::list<BTreeData> node_keys = ReadKeys (node, node_header);
+	std::list<BTreeData>::iterator it = node_keys.begin ();
+
+	std::cout << "Nodo  : " << num << std::endl;
+	std::cout << "Items : " << node_header.item_count << std::endl;
+	std::cout << "Free  : " << node_header.free_space << " (" << (header.block_size - sizeof (BTreeNodeHeader)) << ")" << std::endl;
+	while (it != node_keys.end ()) {
+		std::string s = (*it);
+		std::cout << "(" << s << ") "; 
+	}
+	std::cout << std::endl;
+}
+