1 files changed, 181 insertions, 0 deletions
diff --git a/cli/usage.hxx b/cli/usage.hxx
new file mode 100644
index 0000000..3aeb30b
--- /dev/null
+++ b/cli/usage.hxx
@@ -0,0 +1,181 @@
+// file      : cli/usage.hxx
+// author    : Boris Kolpackov <boris@codesynthesis.com>
+// copyright : Copyright (c) 2009 Code Synthesis Tools CC
+// license   : MIT; see accompanying LICENSE file
+
+#ifndef CLI_USAGE_HXX
+#define CLI_USAGE_HXX
+
+#include <cstddef> // std::size_t
+#include <cstdlib> // std::abort
+
+#include <cutl/compiler/code-stream.hxx>
+
+template <typename C>
+class usage_indenter: public cutl::compiler::code_stream<C>
+{
+public:
+  usage_indenter (cutl::compiler::code_stream<C>& out)
+      : out_ (out),
+        option_length_ (0),
+        construct_ (con_newline)
+  {
+  }
+
+private:
+  usage_indenter (usage_indenter const&);
+
+  usage_indenter&
+  operator= (usage_indenter const&);
+
+public:
+  virtual void
+  put (C c)
+  {
+    switch (c)
+    {
+    case '\n':
+      {
+        switch (construct_)
+        {
+        case con_newline:
+          {
+            out_.put (c);
+            break;
+          }
+        case con_option:
+          {
+            construct_ = con_newline;
+            break;
+          }
+        case con_description:
+          {
+            out_.put (c);
+            construct_ = con_newline;
+            break;
+          }
+        default:
+          {
+            std::abort ();
+          }
+        }
+
+        break;
+      }
+    case '-':
+      {
+        switch (construct_)
+        {
+        case con_newline:
+          {
+            construct_ = con_option;
+            option_length_ = 0;
+            output_indentation ();
+            out_.put (c);
+            ++option_length_;
+            break;
+          }
+        case con_option:
+          {
+            ++option_length_;
+            //fall through
+          }
+        case con_description:
+          {
+            out_.put (c);
+            break;
+          }
+        default:
+          {
+            std::abort ();
+          }
+        }
+
+        break;
+      }
+    default:
+      {
+        switch (construct_)
+        {
+        case con_newline:
+          {
+            construct_ = con_description;
+            output_indentation ();
+            out_.put (c);
+            break;
+          }
+        case con_option:
+          {
+            ++option_length_;
+            //fall through
+          }
+        default:
+          {
+            out_.put (c);
+            break;
+          }
+        }
+
+        break;
+      }
+    }
+  }
+
+  virtual void
+  unbuffer ()
+  {
+  }
+
+private:
+  void
+  output_indentation ()
+  {
+    std::size_t spaces;
+
+    switch (construct_)
+    {
+    case con_option:
+      {
+        spaces = 2;
+        option_length_ += 2;
+        break;
+      }
+    case con_description:
+      {
+        spaces = 29;
+
+        if (option_length_)
+        {
+          if (option_length_ > spaces)
+            spaces = 1;
+          else
+            spaces -= option_length_;
+
+          option_length_ = 0;
+        }
+
+        break;
+      }
+    default:
+      {
+        std::abort ();
+      }
+    }
+
+    while (spaces--)
+      out_.put (' ');
+  }
+
+private:
+  cutl::compiler::code_stream<C>& out_;
+  size_t option_length_;
+
+  enum construct
+  {
+    con_newline,
+    con_option,
+    con_description
+  } construct_;
+};
+
+#endif // CLI_USAGE_HXX