add append input for non-empty line

4 files changed, 37 insertions, 15 deletions

diff --git a/include/line/cursor.h b/include/line/cursor.h
index 39160dc..1641a28 100644
--- a/include/line/cursor.h
+++ b/include/line/cursor.h
@@ -13,10 +13,14 @@ struct T_position
     int col;
 };
 
+// 1-based
 inline int cursor_row;
 inline int cursor_col;
-
 inline int line_end_pos;
+inline int line_begin_pos;
+
+// 0-based index
+inline int line_buffer_index;
 
 T_position get_cursor_position();
 
@@ -26,5 +30,7 @@ void move_cursor(char c);
 
 void cursor_input(char c, std::string &buffer);
 
+int get_cursor_real_pos();
+
 }
 
diff --git a/module-test/line_test.cc b/module-test/line_test.cc
index e2784d9..874b5cf 100644
--- a/module-test/line_test.cc
+++ b/module-test/line_test.cc
@@ -23,6 +23,7 @@ using namespace ov4;
 
 int main()
 {
+    print("shell $ ");
     enable_raw();
     T_position pos = get_cursor_position();
     cursor_row = pos.row;
diff --git a/src/line/cursor.cc b/src/line/cursor.cc
index 9ff8bbc..9630d34 100644
--- a/src/line/cursor.cc
+++ b/src/line/cursor.cc
@@ -40,16 +40,24 @@ T_position get_cursor_position()
     }
     pos.row = row;
     pos.col = col;
-    print("row {}, col {}\r\n", row, col);
-    fflush(stdout);
+    // print("row {}, col {}\r\n", row, col);
+    // fflush(stdout);
     return pos;
 } 
 
 void print_override(const std::string &s)
 {
+
     print("\x1b[s"); fflush(stdout);
-    print("\r");
-    fflush(stdout);
+    print("\r"); fflush(stdout);
+
+    // move to the "start" of the zone
+    // should skip prompt zone
+    print("\x1b[{}C", line_begin_pos-1); fflush(stdout);
+
+    // erase rest of it
+    print("\x1b[K"); fflush(stdout);
+    
     print("{}", s);
     fflush(stdout);
     //line_end_pos = s.size()+1;
@@ -71,19 +79,19 @@ void move_cursor(char c)
         //     cursor_row++;
         //     break;
         case 'C':
-            if (cursor_col < line_end_pos)
+            if (get_cursor_real_pos() < line_end_pos)
             {
                 print("\x1b[C");
                 fflush(stdout);
-                cursor_col++;
+                line_buffer_index++;
             }
             break;
         case 'D':
-            if (cursor_col > 1)
+            if (get_cursor_real_pos() > line_begin_pos)
             {
                 print("\x1b[D");
                 fflush(stdout);
-                cursor_col--;
+                line_buffer_index--;
             }
             break;
         default:
@@ -95,18 +103,23 @@ void cursor_input(char c, std::string &buffer)
 {
     if (c != '\b')
     {
-        buffer.insert(cursor_col-1, 1, c);
+        buffer.insert(line_buffer_index, 1, c);
         print("\x1b[C"); fflush(stdout);
-        cursor_col++;
-        line_end_pos = buffer.size()+1;
+        line_buffer_index++;
+        line_end_pos = line_begin_pos + buffer.size();
         return;
     }
 
     // BACKSPACE
-    buffer.erase(cursor_col-1, 1);
+    buffer.erase(line_buffer_index, 1);
     print("\x1b[D"); fflush(stdout);
-    cursor_col--;
-    line_end_pos = buffer.size()+1;
+    line_buffer_index--;
+    line_end_pos = line_begin_pos + buffer.size();
+}
+
+int get_cursor_real_pos()
+{
+    return line_begin_pos + line_buffer_index;
 }
 
 }
diff --git a/src/line/mode.cc b/src/line/mode.cc
index 2ef470d..4122411 100644
--- a/src/line/mode.cc
+++ b/src/line/mode.cc
@@ -68,6 +68,8 @@ void clear_below()
 
 string readline()
 {
+    T_position pos = get_cursor_position();
+    line_begin_pos = pos.col;
     string buffer;
     char c;
     while (read(STDIN_FILENO, &c, 1) == 1)