From c5fb58fe686d1f9218bcb9273e47fc03ceba49ca Mon Sep 17 00:00:00 2001
From: MarkBaker <mark@demon-angel.eu>
Date: Wed, 5 Apr 2023 09:02:47 +0200
Subject: [PATCH 1/2] Allow color palette index values in number format masks

---
 .../Style/NumberFormat/Formatter.php          | 10 ++++-
 tests/data/Style/NumberFormat.php             | 37 +++++++++++++++++++
 2 files changed, 45 insertions(+), 2 deletions(-)

diff --git a/src/PhpSpreadsheet/Style/NumberFormat/Formatter.php b/src/PhpSpreadsheet/Style/NumberFormat/Formatter.php
index 79c5b5d3d9..41a17151d3 100644
--- a/src/PhpSpreadsheet/Style/NumberFormat/Formatter.php
+++ b/src/PhpSpreadsheet/Style/NumberFormat/Formatter.php
@@ -3,6 +3,7 @@
 namespace PhpOffice\PhpSpreadsheet\Style\NumberFormat;
 
 use PhpOffice\PhpSpreadsheet\Calculation\Calculation;
+use PhpOffice\PhpSpreadsheet\Reader\Xls\Color\BIFF8;
 use PhpOffice\PhpSpreadsheet\RichText\RichText;
 use PhpOffice\PhpSpreadsheet\Style\Color;
 use PhpOffice\PhpSpreadsheet\Style\NumberFormat;
@@ -67,14 +68,19 @@ private static function splitFormatForSectionSelection(array $sections, $value):
         //   3 sections:  [POSITIVE/TEXT] [NEGATIVE] [ZERO]
         //   4 sections:  [POSITIVE] [NEGATIVE] [ZERO] [TEXT]
         $sectionCount = count($sections);
-        $color_regex = '/\\[(' . implode('|', Color::NAMED_COLORS) . ')\\]/mui';
+        // Colour could be a named colour, or a numeric index entry in the colour-palette
+        $color_regex = '/\\[(' . implode('|', Color::NAMED_COLORS) . '|color\\s*(\\d+))\\]/mui';
         $cond_regex = '/\\[(>|>=|<|<=|=|<>)([+-]?\\d+([.]\\d+)?)\\]/';
         $colors = ['', '', '', '', ''];
         $conditionOperations = ['', '', '', '', ''];
         $conditionComparisonValues = [0, 0, 0, 0, 0];
         for ($idx = 0; $idx < $sectionCount; ++$idx) {
             if (preg_match($color_regex, $sections[$idx], $matches)) {
-                $colors[$idx] = $matches[0];
+                if (isset($matches[2])) {
+                    $colors[$idx] = '#' . BIFF8::lookup((int) $matches[2] + 7)['rgb'];
+                } else {
+                    $colors[$idx] = $matches[0];
+                }
                 $sections[$idx] = (string) preg_replace($color_regex, '', $sections[$idx]);
             }
             if (preg_match($cond_regex, $sections[$idx], $matches)) {
diff --git a/tests/data/Style/NumberFormat.php b/tests/data/Style/NumberFormat.php
index 43291c3e94..733f8c469b 100644
--- a/tests/data/Style/NumberFormat.php
+++ b/tests/data/Style/NumberFormat.php
@@ -448,6 +448,43 @@
         -2,
         '[Green]"Positive";[Red]"Negative";[Blue]"Zero"',
     ],
+    // Colour palette index
+    [
+        '+710',
+        710,
+        '[color 10]+#,##0;[color 12]-#,##0',
+    ],
+    [
+        '-710',
+        -710,
+        '[color 10]+#,##0;[color 12]-#,##0',
+    ],
+    // Colour palette index
+    [
+        '+710',
+        710,
+        '[color10]+#,##0;[color12]-#,##0',
+    ],
+    [
+        '-710',
+        -710,
+        '[color10]+#,##0;[color12]-#,##0',
+    ],
+    [
+        '-710',
+        -710,
+        '[color01]+#,##0;[color02]-#,##0',
+    ],
+    [
+        '-710',
+        -710,
+        '[color08]+#,##0;[color09]-#,##0',
+    ],
+    [
+        '-710',
+        -710,
+        '[color55]+#,##0;[color56]-#,##0',
+    ],
     // Value break points
     [
         '<=3500 red',

From 44c74f8eca57692b0c670aa784303a1758cc13b1 Mon Sep 17 00:00:00 2001
From: MarkBaker <mark@demon-angel.eu>
Date: Thu, 6 Apr 2023 10:18:22 +0200
Subject: [PATCH 2/2] Update change log

---
 CHANGELOG.md | 1 +
 1 file changed, 1 insertion(+)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 0e8772ec36..70cde7180c 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -47,6 +47,7 @@ and this project adheres to [Semantic Versioning](https://semver.org).
 - Xlsx Writer Honor Alignment in Default Font. [Issue #3443](https://github.com/PHPOffice/PhpSpreadsheet/issues/3443) [PR #3459](https://github.com/PHPOffice/PhpSpreadsheet/pull/3459)
 - Support Border for Charts. [PR #3462](https://github.com/PHPOffice/PhpSpreadsheet/pull/3462)
 - Error in "this row" structured reference calculation (cached result from first row when using a range) [Issue #3504](https://github.com/PHPOffice/PhpSpreadsheet/issues/3504) [PR #3505](https://github.com/PHPOffice/PhpSpreadsheet/pull/3505)
+- Allow colour palette index references in Number Format masks [Issue #3511](https://github.com/PHPOffice/PhpSpreadsheet/issues/3511) [PR #3512](https://github.com/PHPOffice/PhpSpreadsheet/pull/3512)
 
 
 ## 1.28.0 - 2023-02-25