Add documentation to DrawsTabs trait

src/Themes/Default/Concerns/DrawsTabs.php

@@ -21,23 +21,34 @@ protected function tabs(
     ): string {
         $strippedWidth = fn (string $value): int => mb_strwidth($this->stripEscapeSequences($value));
 
+        // Build the top row for the tabs by adding whitespace equal
+        // to the width of each tab plus padding, or by adding an
+        // equal number of box characters for the selected tab.
         $top_row = $tabs->map(fn($value, $key) => $key === $selected
             ? '╭' . str_repeat('─', $strippedWidth($value) + 2) . '╮'
             : str_repeat(' ', $strippedWidth($value) + 4)
         )->implode('');
 
+        // Build the middle row for the tabs by adding the tab name
+        // surrounded by some padding. But if the tab is selected
+        // then highlight the tab and surround it in box chars.
         $middle_row = $tabs->map(fn($value, $key) => $key === $selected
             ? "{$this->dim('│')} {$this->{$color}($value)} {$this->dim('│')}"
             : "  {$value}  "
         )->implode('');
 
+        // Build the bottom row for the tabs by adding box characters equal to the width
+        // of each tab, plus padding. If the tab is selected, add the appropriate box
+        // characters instead. Finally, pad the whole line to fill the width fully.
         $bottom_row = $tabs->map(fn($value, $key) => $key === $selected
             ? '┴' . str_repeat('─', $strippedWidth($value) + 2) . '┴'
             : str_repeat('─', $strippedWidth($value) + 4)
         )->implode('');
         $bottom_row = $this->pad($bottom_row, $width, '─');
 
-        // automatic horizontal tab scrolling
+        // If the tabs are wider than the provided width, we need to trim the tabs to fit.
+        // We remove the appropriate number of characters from the beginning and end of
+        // each row by using the highlighted tab's index to get it's scroll position.
         if ($strippedWidth($top_row) > $width) {
             $scroll = $selected / ($tabs->count() - 1);
             $chars_to_kill = $strippedWidth($top_row) - $width;
@@ -47,6 +58,9 @@ protected function tabs(
             }
         }
 
+        // We wait until now to dim the top and bottom
+        // rows, otherwise the horizontal scrolling
+        // could easily strip those instructions.
         return collect([$this->dim($top_row), $middle_row, $this->dim($bottom_row)])->implode(PHP_EOL);
     }
 }