gui: allow specifying colors for copy mode and quickselect

refs: https://github.com/wez/wezterm/issues/2320

```lua
return {
  colors = {
    copy_mode_active_highlight_fg={Color="red"},
    copy_mode_active_highlight_bg={Color="blue"},
    copy_mode_inactive_highlight_fg={AnsiColor="Black"},
    copy_mode_inactive_highlight_bg={AnsiColor="White"},
    quick_select_label_fg={Color="white"},
    quick_select_label_bg={Color="blue"},
    quick_select_match_fg={Color="grey"},
    quick_select_match_bg={Color="skyblue"},
  }
}
```

config/src/color.rs

@@ -3,7 +3,8 @@ use luahelper::impl_lua_conversion_dynamic;
 use std::convert::{TryFrom, TryInto};
 use std::str::FromStr;
 use termwiz::cell::CellAttributes;
-pub use termwiz::color::{ColorSpec, RgbColor, SrgbaTuple};
+use termwiz::color::ColorSpec as TWColorSpec;
+pub use termwiz::color::{AnsiColor, ColorAttribute, RgbColor, SrgbaTuple};
 use wezterm_dynamic::{FromDynamic, ToDynamic};
 use wezterm_term::color::ColorPalette;
 
@@ -90,6 +91,39 @@ impl TryFrom<String> for RgbaColor {
     }
 }
 
+#[derive(Debug, FromDynamic, ToDynamic, Clone, Copy, PartialEq, Eq)]
+pub enum ColorSpec {
+    AnsiColor(AnsiColor),
+    Color(RgbaColor),
+    Default,
+}
+
+impl From<AnsiColor> for ColorSpec {
+    fn from(color: AnsiColor) -> ColorSpec {
+        Self::AnsiColor(color)
+    }
+}
+
+impl Into<ColorAttribute> for ColorSpec {
+    fn into(self) -> ColorAttribute {
+        match self {
+            Self::AnsiColor(c) => ColorAttribute::PaletteIndex(c.into()),
+            Self::Color(RgbaColor { color }) => ColorAttribute::TrueColorWithDefaultFallback(color),
+            Self::Default => ColorAttribute::Default,
+        }
+    }
+}
+
+impl Into<TWColorSpec> for ColorSpec {
+    fn into(self) -> TWColorSpec {
+        match self {
+            Self::AnsiColor(c) => c.into(),
+            Self::Color(RgbaColor { color }) => TWColorSpec::TrueColor(color),
+            Self::Default => TWColorSpec::Default,
+        }
+    }
+}
+
 #[derive(Default, Debug, Clone, PartialEq, FromDynamic, ToDynamic)]
 pub struct Palette {
     /// The text color to use when the attributes are reset to default
@@ -124,6 +158,16 @@ pub struct Palette {
     pub visual_bell: Option<RgbaColor>,
     /// The color to use for the cursor when a dead key or leader state is active
     pub compose_cursor: Option<RgbaColor>,
+
+    pub copy_mode_active_highlight_fg: Option<ColorSpec>,
+    pub copy_mode_active_highlight_bg: Option<ColorSpec>,
+    pub copy_mode_inactive_highlight_fg: Option<ColorSpec>,
+    pub copy_mode_inactive_highlight_bg: Option<ColorSpec>,
+
+    pub quick_select_label_fg: Option<ColorSpec>,
+    pub quick_select_label_bg: Option<ColorSpec>,
+    pub quick_select_match_fg: Option<ColorSpec>,
+    pub quick_select_match_bg: Option<ColorSpec>,
 }
 impl_lua_conversion_dynamic!(Palette);
 
@@ -238,8 +282,8 @@ impl TabBarColor {
             .set_underline(self.underline)
             .set_italic(self.italic)
             .set_strikethrough(self.strikethrough)
-            .set_background(ColorSpec::TrueColor(*self.bg_color))
-            .set_foreground(ColorSpec::TrueColor(*self.fg_color));
+            .set_background(TWColorSpec::TrueColor(*self.bg_color))
+            .set_foreground(TWColorSpec::TrueColor(*self.fg_color));
         attr
     }
 }

wezterm-gui/src/overlay/copy.rs

@@ -956,6 +956,9 @@ impl Pane for CopyOverlay {
 
         let (top, mut lines) = self.delegate.get_lines(lines);
 
+        let config = config::configuration();
+        let colors = &config.resolved_palette;
+
         // Process the lines; for the search row we want to render instead
         // the search UI.
         // For rows with search results, we want to highlight the matching ranges
@@ -994,13 +997,29 @@ impl Pane for CopyOverlay {
                         {
                             if Some(m.result_index) == renderer.result_pos {
                                 cell.attrs_mut()
-                                    .set_background(AnsiColor::Yellow)
-                                    .set_foreground(AnsiColor::Black)
+                                    .set_background(
+                                        colors
+                                            .copy_mode_active_highlight_bg
+                                            .unwrap_or(AnsiColor::Yellow.into()),
+                                    )
+                                    .set_foreground(
+                                        colors
+                                            .copy_mode_active_highlight_fg
+                                            .unwrap_or(AnsiColor::Black.into()),
+                                    )
                                     .set_reverse(false);
                             } else {
                                 cell.attrs_mut()
-                                    .set_background(AnsiColor::Fuchsia)
-                                    .set_foreground(AnsiColor::Black)
+                                    .set_background(
+                                        colors
+                                            .copy_mode_inactive_highlight_bg
+                                            .unwrap_or(AnsiColor::Fuchsia.into()),
+                                    )
+                                    .set_foreground(
+                                        colors
+                                            .copy_mode_inactive_highlight_fg
+                                            .unwrap_or(AnsiColor::Black.into()),
+                                    )
                                     .set_reverse(false);
                             }
                         }

wezterm-gui/src/overlay/quickselect.rs

@@ -458,6 +458,7 @@ impl Pane for QuickSelectOverlay {
         let dims = self.get_dimensions();
 
         let (top, mut lines) = self.delegate.get_lines(lines);
+        let colors = renderer.config.resolved_palette.clone();
 
         // Process the lines; for the search row we want to render instead
         // the search UI.
@@ -492,8 +493,16 @@ impl Pane for QuickSelectOverlay {
                         if let Some(cell) = line.cells_mut_for_attr_changes_only().get_mut(cell_idx)
                         {
                             cell.attrs_mut()
-                                .set_background(AnsiColor::Black)
-                                .set_foreground(AnsiColor::Green)
+                                .set_background(
+                                    colors
+                                        .quick_select_match_bg
+                                        .unwrap_or(AnsiColor::Black.into()),
+                                )
+                                .set_foreground(
+                                    colors
+                                        .quick_select_match_fg
+                                        .unwrap_or(AnsiColor::Green.into()),
+                                )
                                 .set_reverse(false);
                         }
                     }
@@ -502,9 +511,17 @@ impl Pane for QuickSelectOverlay {
                             .get_cell(idx)
                             .map(|cell| cell.attrs().clone())
                             .unwrap_or_else(|| CellAttributes::default());
-                        attr.set_background(AnsiColor::Black)
-                            .set_foreground(AnsiColor::Olive)
-                            .set_reverse(false);
+                        attr.set_background(
+                            colors
+                                .quick_select_label_bg
+                                .unwrap_or(AnsiColor::Black.into()),
+                        )
+                        .set_foreground(
+                            colors
+                                .quick_select_label_fg
+                                .unwrap_or(AnsiColor::Olive.into()),
+                        )
+                        .set_reverse(false);
                         line.set_cell(m.range.start + idx, Cell::new(c, attr), SEQ_ZERO);
                     }
                 }