dbus-top: initial commits

This commit covers the basic functionalities of the dbus-top tool.

The UI is divided into 3 windows as follows:

  +--------------------------+  Window list
  |         Window A         |  A: Summary statistics
  +------------+-------------+  B: Sensor list or detail
  |  Window B  |   Window C  |  C: Detailed statistics
  +------------+-------------+

To navigate the UI:
* Use tab to navigate each window

When a window is highlighted:
  In Window B:
  * Press esc key 3 times to leave the current sensor selection

  In Window C:
  * Press [Enter] to show/hide pop-up menu for column selectio
  * Press [Left]  to move highlight cursor to the left
  * Press [Right] to move highlight cursor to the right
  * Press [A] to sort by the highlighted column in ascending order
  * Press [D] to sort by the highlighted column in descending order

To add recipe to Yocto and build the recipe:
1) Copy and paste the content of the .bb file into a folder that can be
   detected by bitbake, such as meta-phosphor/recipes-phosphor/ipmi.
2) run "devtool modify -n dbus-top (path_to_openbmc_tools)/dbus-top/".

Signed-off-by: Adedeji Adebisi <adedejiadebisi01@gmail.com>
Change-Id: Id58ba30b815cfd9d18f54cf477d749dbdbc4545b
diff --git a/dbus-top/menu.hpp b/dbus-top/menu.hpp
new file mode 100644
index 0000000..afb4110
--- /dev/null
+++ b/dbus-top/menu.hpp
@@ -0,0 +1,122 @@
+// Copyright 2021 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#pragma once
+#include "main.hpp"
+
+#include <ncurses.h>
+
+#include <string>
+#include <vector>
+class DBusTopWindow;
+class ArrowKeyNavigationMenu
+{
+  public:
+    explicit ArrowKeyNavigationMenu(WINDOW* win) :
+        win_(win), h_padding_(2), col_width_(15), h_spacing_(2), idx0_(INVALID),
+        idx1_(INVALID), choice_(INVALID), parent_(nullptr)
+    {}
+    explicit ArrowKeyNavigationMenu(DBusTopWindow* view);
+    void LoadDummyValues()
+    {
+        items_.clear();
+        items_.push_back("Sender");
+        items_.push_back("Destination");
+        items_.push_back("Interface");
+        items_.push_back("Path");
+        items_.push_back("Member");
+    }
+
+    void OnKeyDown(const std::string& key);
+    void Render();
+    void MoveCursorAlongSecondaryAxis(int delta);
+    void MoveCursorAlongPrimaryAxis(int delta);
+    int DispEntriesPerRow()
+    {
+        int ncols = 0;
+        while (true)
+        {
+            int next = ncols + 1;
+            int w = 2 * h_padding_ + col_width_ * next;
+            if (next > 1)
+                w += (next - 1) * h_spacing_;
+            if (w <= rect_.w - 2)
+            {
+                ncols = next;
+            }
+            else
+            {
+                break;
+            }
+        }
+        return ncols;
+    }
+
+    int DispEntriesPerColumn()
+    {
+        return rect_.h;
+    }
+
+    void SetRect(const Rect& rect)
+    {
+        rect_ = rect;
+    }
+
+    enum Order
+    {
+        ColumnMajor,
+        RowMajor,
+    };
+
+    void SetOrder(Order o)
+    {
+        order = o;
+    }
+
+    int Choice()
+    {
+        return choice_;
+    }
+
+    void Deselect()
+    {
+        choice_ = INVALID;
+    }
+
+    bool Empty()
+    {
+        return items_.empty();
+    }
+
+    void SetChoiceAndConstrain(int c);
+    Rect rect_;
+    void AddItem(const std::string& s);
+    bool RemoveHighlightedItem(std::string* ret); // returns true if successful
+    std::vector<std::string> Items()
+    {
+        return items_;
+    }
+
+    void do_Render(bool is_column_major);
+    std::vector<std::string> items_;
+    WINDOW* win_;
+    int h_padding_;
+    int col_width_;
+    int h_spacing_;
+    int idx0_, idx1_;
+    int choice_;
+    DBusTopWindow* parent_;
+    Order order;
+};
+