5 files changed, 45 insertions, 3 deletions

diff --git a/command.c b/command.c
index e9ffd75..5ee0302 100644
--- a/command.c
+++ b/command.c
@@ -337,5 +337,8 @@ void command_execute(Ted *ted, Command c, i64 argument) {
 			}
 		}
 		break;
+	case CMD_SPLIT_JOIN:
+		node_join(ted, node);
+		break;
 	}
 }
diff --git a/command.h b/command.h
index a74f42a..a8efe35 100644
--- a/command.h
+++ b/command.h
@@ -74,6 +74,7 @@ ENUM_U16 {
 
 	CMD_SPLIT_HORIZONTAL,
 	CMD_SPLIT_VERTICAL,
+	CMD_SPLIT_JOIN,
 	
 	CMD_ESCAPE, // by default this is the escape key. closes menus, etc.
 
@@ -145,6 +146,7 @@ static CommandName const command_names[CMD_COUNT] = {
 	{"goto-line", CMD_GOTO_LINE},
 	{"split-horizontal", CMD_SPLIT_HORIZONTAL},
 	{"split-vertical", CMD_SPLIT_VERTICAL},
+	{"split-join", CMD_SPLIT_JOIN},
 	{"escape", CMD_ESCAPE},
 };
 
diff --git a/main.c b/main.c
index e5b36c2..d7dbc3c 100644
--- a/main.c
+++ b/main.c
@@ -1,7 +1,7 @@
 // @TODO:
-// - Ctrl+j = :join
 // - split depth limit
 // - resize split (i.e. change split_pos)
+// - move tabs between nodes
 
 // - Windows installation
 // - on crash, output backtrace to log
diff --git a/node.c b/node.c
index 810b657..f2ac41f 100644
--- a/node.c
+++ b/node.c
@@ -34,6 +34,7 @@ static void node_free(Node *node) {
 
 // returns index of parent in ted->nodes, or -1 if this is the root node.
 static i32 node_parent(Ted *ted, u16 node_idx) {
+	assert(node_idx < TED_MAX_NODES && ted->nodes_used[node_idx]);
 	for (u16 i = 0; i < TED_MAX_NODES; ++i) {
 		if (ted->nodes_used[i]) {
 			Node *node = &ted->nodes[i];
@@ -46,9 +47,44 @@ static i32 node_parent(Ted *ted, u16 node_idx) {
 	return -1;
 }
 
+// join this node with its sibling
+static void node_join(Ted *ted, Node *node) {
+	i32 parent_idx = node_parent(ted, (u16)(node - ted->nodes));
+	if (parent_idx >= 0) {
+		Node *parent = &ted->nodes[parent_idx];
+		Node *a = &ted->nodes[parent->split_a];
+		Node *b = &ted->nodes[parent->split_b];
+		if (a->tabs && b->tabs) {
+			if (ted->active_node == a || ted->active_node == b) {
+				ted->active_node = parent;
+			}
+			arr_foreach_ptr(a->tabs, u16, tab) {
+				arr_add(parent->tabs, *tab);
+			}
+			arr_foreach_ptr(b->tabs, u16, tab) {
+				arr_add(parent->tabs, *tab);
+			}
+			if (parent->tabs) {
+				if (node == a) {
+					parent->active_tab = a->active_tab;
+				} else {
+					parent->active_tab = (u16)arr_len(a->tabs) + b->active_tab;
+				}
+				node_free(a);
+				node_free(b);
+				ted->nodes_used[parent->split_a] = false;
+				ted->nodes_used[parent->split_b] = false;
+			}
+		}
+	}
+}
+
 static void node_close(Ted *ted, u16 node_idx) {
 	assert(node_idx < TED_MAX_NODES);
 	assert(ted->nodes_used[node_idx]);
+	i32 parent_idx = node_parent(ted, node_idx);
+	ted->nodes_used[node_idx] = false;
+
 	Node *node = &ted->nodes[node_idx];
 
 	// delete all associated buffers
@@ -58,9 +94,7 @@ static void node_close(Ted *ted, u16 node_idx) {
 	}
 
 	node_free(node);
-	ted->nodes_used[node_idx] = false;
 
-	i32 parent_idx = node_parent(ted, node_idx);
 	if (parent_idx < 0) {
 		// no parent; this must be the root node
 		ted->active_node = NULL;
@@ -90,6 +124,7 @@ static void node_close(Ted *ted, u16 node_idx) {
 	}
 }
 
+
 // close tab, WITHOUT checking for unsaved changes!
 // returns true if the node is still open
 static bool node_tab_close(Ted *ted, Node *node, u16 index) {
diff --git a/ted.cfg b/ted.cfg
index da4a1a3..1d4e64e 100644
--- a/ted.cfg
+++ b/ted.cfg
@@ -123,6 +123,8 @@ Ctrl+g = :goto-line
 
 Ctrl+/ = :split-horizontal
 Ctrl+Shift+/ = :split-vertical
+# unsplit
+Ctrl+j = :split-join
 
 Escape = :escape