From 3cb898593c67ccfa13a1f0f5b37601b9bcea806e Mon Sep 17 00:00:00 2001
From: Pierre-Anthony Lemieux <pal@palemieux.com>
Date: Thu, 21 Dec 2023 21:45:51 -0800
Subject: [PATCH] Added support for preserve textAlign

---
 src/main/python/ttconv/filters/doc/lcd.py | 14 ++++++++---
 src/test/python/test_lcd_filter.py        | 29 +++++++++++++++++++++++
 src/test/python/test_tt.py                |  2 +-
 3 files changed, 41 insertions(+), 4 deletions(-)

diff --git a/src/main/python/ttconv/filters/doc/lcd.py b/src/main/python/ttconv/filters/doc/lcd.py
index d33dd527..d591efd8 100644
--- a/src/main/python/ttconv/filters/doc/lcd.py
+++ b/src/main/python/ttconv/filters/doc/lcd.py
@@ -37,7 +37,7 @@
 from ttconv.filters.supported_style_properties import SupportedStylePropertiesFilter
 from ttconv.isd import StyleProcessors
 from ttconv.model import ContentDocument, ContentElement, Region, P
-from ttconv.style_properties import ColorType, CoordinateType, DisplayAlignType, ExtentType, LengthType, StyleProperties, WritingModeType, NamedColors
+from ttconv.style_properties import TextAlignType, ColorType, CoordinateType, DisplayAlignType, ExtentType, LengthType, StyleProperties, WritingModeType, NamedColors
 import ttconv.utils
 
 LOGGER = logging.getLogger(__name__)
@@ -73,6 +73,9 @@ def name(cls):
   # specifies the safe area as an integer percentage
   safe_area: typing.Optional[int] = field(default=10, metadata={"decoder": int})
 
+  # preserve text alignment the text color
+  preserve_text_align: typing.Optional[bool] = field(default=False, metadata={"decoder": bool})
+
   # overrides the text color
   color: typing.Optional[ColorType] = field(default=None, metadata={"decoder": ttconv.utils.parse_color})
 
@@ -100,6 +103,9 @@ def process(self, doc: ContentDocument) -> ContentDocument:
       StyleProperties.Position: []
     }
 
+    if self.config.preserve_text_align:
+      supported_styles.update({StyleProperties.TextAlign: []})
+
     if self.config.color is None:
       supported_styles.update({StyleProperties.Color: []})
 
@@ -189,7 +195,6 @@ def process(self, doc: ContentDocument) -> ContentDocument:
       region.set_style(StyleProperties.DisplayAlign, new_display_align)
 
       # reposition region
-      # TODO: allow configurable safe area
       region.set_style(
         StyleProperties.Origin,
         CoordinateType(
@@ -236,4 +241,7 @@ def process(self, doc: ContentDocument) -> ContentDocument:
 
     # apply text color
     if doc.get_body() is not None and self.config.color is not None:
-      doc.get_body().set_style(StyleProperties.Color, self.config.color)
\ No newline at end of file
+      doc.get_body().set_style(StyleProperties.Color, self.config.color)
+
+    if doc.get_body() is not None and not self.config.preserve_text_align:
+      doc.get_body().set_style(StyleProperties.TextAlign, TextAlignType.center)
diff --git a/src/test/python/test_lcd_filter.py b/src/test/python/test_lcd_filter.py
index cef25221..ad6f7ef9 100644
--- a/src/test/python/test_lcd_filter.py
+++ b/src/test/python/test_lcd_filter.py
@@ -293,6 +293,35 @@ def test_region_resizing(self):
       styles.DisplayAlignType.after
     )
 
+  def test_text_align(self):
+    doc = model.ContentDocument()
+
+    # r1: origin=10,10 extent=80,20
+    r1 = model.Region("r1", doc)
+    doc.put_region(r1)
+
+    # body
+    body = model.Body(doc)
+    doc.set_body(body)
+
+    # div
+    div = model.Div(doc)
+    body.push_child(div)
+
+    # p1: r1
+    p1 = model.P(doc)
+    p1.set_id("p1")
+    p1.set_region(r1)
+    p1.set_style(styles.StyleProperties.TextAlign, styles.TextAlignType.end)
+    div.push_child(p1)
+
+    # apply filter
+    filter = LCDFilter(LCDFilterConfig())
+
+    filter.process(doc)
+
+    self.assertIsNone(p1.get_style(styles.StyleProperties.TextAlign))
+    self.assertEqual(body.get_style(styles.StyleProperties.TextAlign), styles.TextAlignType.center)
 
 if __name__ == '__main__':
   unittest.main()
diff --git a/src/test/python/test_tt.py b/src/test/python/test_tt.py
index e1c36a0f..39bcb95b 100644
--- a/src/test/python/test_tt.py
+++ b/src/test/python/test_tt.py
@@ -221,7 +221,7 @@ def test_lcd_filter(self):
       '-i', in_path,
       '-o', out_path,
       '--filter', 'lcd',
-      '--config', '{"lcd": {"bg_color": "blue", "safe_area": 0, "color": "red"}}'
+      '--config', '{"lcd": {"bg_color": "blue", "safe_area": 0, "color": "red", "preserve_text_align": true}}'
       ])
 
 if __name__ == '__main__':