lib: add xterm policy

1 files changed, 136 insertions, 44 deletions

diff --git a/ttwhy/scanners/terminal_policies.cppm b/ttwhy/scanners/terminal_policies.cppm
index e5863d3..bf7c126 100644
--- a/ttwhy/scanners/terminal_policies.cppm
+++ b/ttwhy/scanners/terminal_policies.cppm
@@ -1,70 +1,162 @@
 module;
 
+#include <optional>
 #include <string>
 
 export module ttwhy.scanners:terminal_policies;
 
-import :events;
-import :concepts;
+import :terminal_events;
+import :terminal_concepts;
 
 namespace ttwhy::scanners
 {
 
+  namespace detail
+  {
+    constexpr auto map_vt220_keypad(char terminator) -> std::optional<navigation_key>
+    {
+      switch (terminator)
+      {
+        case '1':
+        case '7':
+          return navigation_key::home;
+        case '2':
+          return navigation_key::insert_key;
+        case '3':
+          return navigation_key::delete_key;
+        case '4':
+        case '8':
+          return navigation_key::end;
+        case '5':
+          return navigation_key::page_up;
+        case '6':
+          return navigation_key::page_down;
+        default:
+          return std::nullopt;
+      }
+    }
+
+    constexpr auto map_vt100_cursor(char terminator) -> std::optional<navigation_key>
+    {
+      switch (terminator)
+      {
+        case 'A':
+          return navigation_key::up;
+        case 'B':
+          return navigation_key::down;
+        case 'C':
+          return navigation_key::right;
+        case 'D':
+          return navigation_key::left;
+        case 'H':
+          return navigation_key::home;
+        case 'F':
+          return navigation_key::end;
+        default:
+          return std::nullopt;
+      }
+    }
+
+  }  // namespace detail
+
+  export template<typename T>
+  using associated_terminal_policy_t = typename T::terminal_policy;
+
   export struct ansi_policy
   {
     constexpr auto static resolve_vt220_keypad(std::string & buffer, ttwhy::ansi_sink auto & sink) -> void
     {
-      auto key = [](auto terminator) {
-        switch (terminator)
-        {
-          case '1':
-          case '7':
-            return navigation_key::home;
-          case '2':
-            return navigation_key::insert_key;
-          case '3':
-            return navigation_key::delete_key;
-          case '4':
-          case '8':
-            return navigation_key::end;
-          case '5':
-            return navigation_key::page_up;
-          case '6':
-            return navigation_key::page_down;
-          default:
-            return static_cast<navigation_key>(-1);
-        }
-      }(buffer.back());
-      sink(navigation_event{key});
+      if (buffer.empty())
+      {
+        return;
+      }
+
+      if (auto key = detail::map_vt220_keypad(buffer.front()))
+      {
+        sink(navigation_event{*key});
+      }
+      buffer.clear();
     }
 
-    constexpr auto static resolve_vt100_cursor(char terminator, ttwhy::ansi_sink auto & sink) -> void
+    constexpr auto static resolve_vt100_cursor(char terminator, std::string &, ttwhy::ansi_sink auto & sink) -> void
     {
-      auto key = [terminator] {
-        switch (terminator)
+      if (auto key = detail::map_vt100_cursor(terminator))
+      {
+        sink(navigation_event{*key});
+      }
+    }
+
+    constexpr auto static resolve_ss3(char terminator, ttwhy::ansi_sink auto & sink) -> void
+    {
+      if (auto key = detail::map_vt100_cursor(terminator))
+      {
+        sink(navigation_event{*key});
+      }
+    }
+  };
+
+  export struct xterm_policy
+  {
+    constexpr auto static parse_modifiers(std::string_view buffer) -> modifier_set
+    {
+      auto delimiter = buffer.find(';');
+      if (delimiter == std::string_view::npos)
+      {
+        return {};
+      }
+
+      auto modifier_string = buffer.substr(delimiter + 1);
+      auto modifier_value = 0u;
+
+      for (auto character : modifier_string)
+      {
+        if (character >= '0' && character <= '9')
         {
-          case 'A':
-            return navigation_key::up;
-          case 'B':
-            return navigation_key::down;
-          case 'C':
-            return navigation_key::right;
-          case 'D':
-            return navigation_key::left;
-          case 'H':
-            return navigation_key::home;
-          case 'F':
-            return navigation_key::end;
-          default:
-            return static_cast<navigation_key>(-1);
+          modifier_value = modifier_value * 10 + static_cast<unsigned int>(character - '0');
         }
-      }();
-      sink(navigation_event{key});
+      }
+
+      if (modifier_value <= 1)
+      {
+        return {};
+      }
+
+      return static_cast<modifier_set>(modifier_value - 1);
+    }
+
+    constexpr auto static resolve_vt220_keypad(std::string & buffer, ttwhy::ansi_sink auto & sink) -> void
+    {
+      if (buffer.empty())
+      {
+        return;
+      }
+
+      auto modifiers = parse_modifiers(buffer);
+
+      if (auto key = detail::map_vt220_keypad(buffer.front()))
+      {
+        sink(navigation_event{*key, modifiers});
+      }
+      buffer.clear();
+    }
+
+    constexpr auto static resolve_vt100_cursor(char terminator, std::string & buffer, ttwhy::ansi_sink auto & sink)
+        -> void
+    {
+      auto modifiers = parse_modifiers(buffer);
+
+      if (auto key = detail::map_vt100_cursor(terminator))
+      {
+        sink(navigation_event{*key, modifiers});
+      }
     }
 
     constexpr auto static resolve_ss3(char terminator, ttwhy::ansi_sink auto & sink) -> void
     {
-      return resolve_vt100_cursor(terminator, sink);
+      if (auto key = detail::map_vt100_cursor(terminator))
+      {
+        sink(navigation_event{*key});
+      }
     }
   };