From 30e18200f8abc4203d7b5c51c28e941c1b7cd006 Mon Sep 17 00:00:00 2001
From: Andrew Kay <git@ajk.me>
Date: Mon, 8 Jun 2020 18:25:14 -0500
Subject: [PATCH] Simplify the TN3270 attribute mapping

---
 oec/tn3270.py        | 17 ++---------------
 tests/test_tn3270.py |  8 +++++++-
 2 files changed, 9 insertions(+), 16 deletions(-)

diff --git a/oec/tn3270.py b/oec/tn3270.py
index 66683ba..5468689 100644
--- a/oec/tn3270.py
+++ b/oec/tn3270.py
@@ -197,21 +197,8 @@ class TN3270Session(Session):
         self.operator_error = None
 
     def _map_attribute(self, attribute):
-        # NOTE: This mapping may not be correct and does not take into account
-        # lightpen detectable fields.
-        if attribute.hidden:
-            return 0xcc
-
-        if attribute.protected:
-            if attribute.intensified:
-                return 0xe8
-
-            return 0xe0
-
-        if attribute.intensified:
-            return 0xc8
-
-        return 0xc0
+        # Only map the protected and display bits - ignore numeric, skip and modified.
+        return 0xc0 | (attribute.value & 0x2c)
 
     def _map_character(self, byte):
         if byte == DUP:
diff --git a/tests/test_tn3270.py b/tests/test_tn3270.py
index 873fc75..3a7f5b5 100644
--- a/tests/test_tn3270.py
+++ b/tests/test_tn3270.py
@@ -58,7 +58,7 @@ class SessionHandleHostTestCase(unittest.TestCase):
 
         self.terminal.display.flush.assert_called()
 
-        self.assertEqual(self.terminal.display.buffer[:105], bytes.fromhex('e0afb1aeb3a4a2b3a4a3e8afb1aeb3a4a2b3a4a300a8adb3a4adb2a8a5a8a4a3ccafb1aeb3a4a2b3a4a300a7a8a3a3a4adc0b4adafb1aeb3a4a2b3a4a3c8b4adafb1aeb3a4a2b3a4a300a8adb3a4adb2a8a5a8a4a3ccb4adafb1aeb3a4a2b3a4a300a7a8a3a3a4ade0'))
+        self.assertEqual(self.terminal.display.buffer[:105], bytes.fromhex('e0afb1aeb3a4a2b3a4a3e8afb1aeb3a4a2b3a4a300a8adb3a4adb2a8a5a8a4a3ecafb1aeb3a4a2b3a4a300a7a8a3a3a4adc0b4adafb1aeb3a4a2b3a4a3c8b4adafb1aeb3a4a2b3a4a300a8adb3a4adb2a8a5a8a4a3ccb4adafb1aeb3a4a2b3a4a300a7a8a3a3a4ade0'))
         self.assertTrue(all([byte == 0x00 for byte in self.terminal.display.buffer[105:]]))
 
         self.assertEqual(self.terminal.display.cursor_index, 8)
@@ -282,6 +282,12 @@ class MockAttribute:
         self.intensified = intensified
         self.hidden = hidden
 
+    @property
+    def value(self):
+        display = 2 if self.intensified else 3 if self.hidden else 0
+
+        return (0x20 if self.protected else 0) | (display << 2)
+
 def _create_screen_cells(rows, columns):
     return [CharacterCell(0x00) for address in range(rows * columns)]