Add SI-prefix-aware sorting column for the parts table

Adds an optional "Name (SI)" column that parses numeric values with SI
prefixes (p, n, u/µ, m, k/K, M, G, T) from part names and sorts by the
resulting physical value. This is useful for electronic components where
alphabetical sorting produces wrong results — e.g. 100nF, 10pF, 1uF
should sort as 10pF < 100nF < 1uF.

Implementation:
- New SiValueSort DQL function with platform-specific SQL generation
  for PostgreSQL (POSIX regex), MySQL/MariaDB (REGEXP_SUBSTR), and
  SQLite (PHP callback registered via the existing middleware).
- The regex is start-anchored: only names beginning with a number are
  matched. Part numbers like "MCP2515" or "Crystal 20MHz" are ignored.
- When SI sort is active, NATSORT is appended as a secondary sort so
  that non-matching parts fall back to natural string ordering instead
  of appearing in arbitrary order.
- The column is opt-in (not in default columns) and displays the parsed
  float value, or an empty cell for non-matching names.

src/DataTables/PartsDataTable.php

@@ -38,6 +38,7 @@ use App\DataTables\Filters\PartFilter;
 use App\DataTables\Filters\PartSearchFilter;
 use App\DataTables\Helpers\ColumnSortHelper;
 use App\DataTables\Helpers\PartDataTableHelper;
+use App\Doctrine\Functions\SiValueSort;
 use App\Doctrine\Helpers\FieldHelper;
 use App\Entity\Parts\ManufacturingStatus;
 use App\Entity\Parts\Part;
@@ -118,6 +119,17 @@ final class PartsDataTable implements DataTableTypeInterface
                 'render' => fn($value, Part $context) => $this->partDataTableHelper->renderName($context),
                 'orderField' => 'NATSORT(part.name)'
             ])
+            ->add('si_name', TextColumn::class, [
+                'label' => $this->translator->trans('part.table.si_name'),
+                'render' => function ($value, Part $context): string {
+                    $siValue = SiValueSort::sqliteSiValue($context->getName());
+                    if ($siValue !== null) {
+                        return htmlspecialchars(sprintf('%g', $siValue));
+                    }
+                    return '';
+                },
+                'orderField' => 'SI_VALUE_SORT(part.name)',
+            ])
             ->add('id', TextColumn::class, [
                 'label' => $this->translator->trans('part.table.id'),
             ])
@@ -484,6 +496,19 @@ final class PartsDataTable implements DataTableTypeInterface
             //$builder->addGroupBy('_bulkImportJob');
         }
 
+        //When sorting by SI value, add NATSORT as a secondary sort so that parts without
+        //an SI-prefixed value fall back to natural string ordering seamlessly.
+        $orderByParts = $builder->getDQLPart('orderBy');
+        foreach ($orderByParts as $orderBy) {
+            foreach ($orderBy->getParts() as $part) {
+                if (str_contains($part, 'SI_VALUE_SORT')) {
+                    $direction = str_contains($part, 'DESC') ? 'DESC' : 'ASC';
+                    $builder->addOrderBy('NATSORT(part.name)', $direction);
+                    break 2;
+                }
+            }
+        }
+
         return $builder;
     }
 

src/Doctrine/Functions/SiValueSort.php

@@ -0,0 +1,187 @@
+<?php
+/*
+ * This file is part of Part-DB (https://github.com/Part-DB/Part-DB-symfony).
+ *
+ *  Copyright (C) 2019 - 2024 Jan Böhmer (https://github.com/jbtronics)
+ *
+ *  This program is free software: you can redistribute it and/or modify
+ *  it under the terms of the GNU Affero General Public License as published
+ *  by the Free Software Foundation, either version 3 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU Affero General Public License for more details.
+ *
+ *  You should have received a copy of the GNU Affero General Public License
+ *  along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+declare(strict_types=1);
+
+namespace App\Doctrine\Functions;
+
+use Doctrine\DBAL\Platforms\AbstractMySQLPlatform;
+use Doctrine\DBAL\Platforms\PostgreSQLPlatform;
+use Doctrine\DBAL\Platforms\SQLitePlatform;
+use Doctrine\ORM\Query\AST\Functions\FunctionNode;
+use Doctrine\ORM\Query\AST\Node;
+use Doctrine\ORM\Query\Parser;
+use Doctrine\ORM\Query\SqlWalker;
+use Doctrine\ORM\Query\TokenType;
+
+/**
+ * Custom DQL function that extracts the first numeric value with an optional SI prefix
+ * from a string and returns the scaled numeric value for sorting.
+ *
+ * Usage: SI_VALUE_SORT(part.name)
+ *
+ * This enables sorting parts by their physical value. For example, capacitors
+ * named "100nF", "1uF", "10pF" will be sorted by actual value: 10pF < 100nF < 1uF.
+ *
+ * Supported SI prefixes: p (pico, 1e-12), n (nano, 1e-9), u/µ (micro, 1e-6),
+ * m (milli, 1e-3), k/K (kilo, 1e3), M (mega, 1e6), G (giga, 1e9), T (tera, 1e12).
+ *
+ * Only matches numbers at the very beginning of the string (ignoring leading whitespace).
+ * Names like "Crystal 20MHz" will NOT match since the number is not at the start.
+ * Names without a recognizable numeric+prefix pattern return NULL and sort last.
+ */
+class SiValueSort extends FunctionNode
+{
+    private ?Node $field = null;
+
+    /**
+     * SI prefix multipliers. Used by the SQLite PHP callback.
+     */
+    private const SI_MULTIPLIERS = [
+        'p' => 1e-12,
+        'n' => 1e-9,
+        'u' => 1e-6,
+        'µ' => 1e-6,
+        'm' => 1e-3,
+        'k' => 1e3,
+        'K' => 1e3,
+        'M' => 1e6,
+        'G' => 1e9,
+        'T' => 1e12,
+    ];
+
+    public function parse(Parser $parser): void
+    {
+        $parser->match(TokenType::T_IDENTIFIER);
+        $parser->match(TokenType::T_OPEN_PARENTHESIS);
+
+        $this->field = $parser->ArithmeticExpression();
+
+        $parser->match(TokenType::T_CLOSE_PARENTHESIS);
+    }
+
+    public function getSql(SqlWalker $sqlWalker): string
+    {
+        assert($this->field !== null, 'Field is not set');
+
+        $platform = $sqlWalker->getConnection()->getDatabasePlatform();
+        $fieldSql = $this->field->dispatch($sqlWalker);
+
+        if ($platform instanceof PostgreSQLPlatform) {
+            return $this->getPostgreSQLSql($fieldSql);
+        }
+
+        if ($platform instanceof AbstractMySQLPlatform) {
+            return $this->getMySQLSql($fieldSql);
+        }
+
+        if ($platform instanceof SQLitePlatform) {
+            return "SI_VALUE({$fieldSql})";
+        }
+
+        // Fallback: return NULL (no SI sorting available)
+        return 'NULL';
+    }
+
+    /**
+     * PostgreSQL implementation using substring() with POSIX regex.
+     */
+    private function getPostgreSQLSql(string $field): string
+    {
+        // Extract the numeric part using POSIX regex, anchored at start (with optional leading whitespace)
+        $numericPart = "CAST(substring({$field} FROM '^\\s*(\\d+\\.?\\d*)\\s*[pnuµmkKMGT]?') AS DOUBLE PRECISION)";
+
+        // Extract the SI prefix character
+        $prefixPart = "substring({$field} FROM '^\\s*\\d+\\.?\\d*\\s*([pnuµmkKMGT])')";
+
+        return $this->buildCaseExpression($numericPart, $prefixPart);
+    }
+
+    /**
+     * MySQL/MariaDB implementation using REGEXP_SUBSTR.
+     */
+    private function getMySQLSql(string $field): string
+    {
+        // Extract the numeric part, anchored at start (with optional leading whitespace)
+        $numericPart = "CAST(REGEXP_SUBSTR({$field}, '^[[:space:]]*[0-9]+\\.?[0-9]*') AS DECIMAL(30,15))";
+
+        // Extract the prefix: get the full number+prefix match anchored at start, then take the last char
+        $fullMatch = "REGEXP_SUBSTR({$field}, '^[[:space:]]*[0-9]+\\.?[0-9]*[[:space:]]*[pnuµmkKMGT]')";
+        $prefixPart = "RIGHT({$fullMatch}, 1)";
+
+        return $this->buildCaseExpression($numericPart, $prefixPart);
+    }
+
+    /**
+     * Build a CASE expression that maps an SI prefix character to a multiplier
+     * and multiplies it with the numeric value.
+     *
+     * @param string $numericExpr SQL expression that evaluates to the numeric part
+     * @param string $prefixExpr SQL expression that evaluates to the SI prefix character
+     * @return string SQL CASE expression
+     */
+    private function buildCaseExpression(string $numericExpr, string $prefixExpr): string
+    {
+        return "(CASE" .
+            " WHEN {$numericExpr} IS NULL THEN NULL" .
+            " WHEN {$prefixExpr} = 'p' THEN {$numericExpr} * 1e-12" .
+            " WHEN {$prefixExpr} = 'n' THEN {$numericExpr} * 1e-9" .
+            " WHEN {$prefixExpr} = 'u' THEN {$numericExpr} * 1e-6" .
+            " WHEN {$prefixExpr} = 'µ' THEN {$numericExpr} * 1e-6" .
+            " WHEN {$prefixExpr} = 'm' THEN {$numericExpr} * 1e-3" .
+            " WHEN {$prefixExpr} = 'k' THEN {$numericExpr} * 1e3" .
+            " WHEN {$prefixExpr} = 'K' THEN {$numericExpr} * 1e3" .
+            " WHEN {$prefixExpr} = 'M' THEN {$numericExpr} * 1e6" .
+            " WHEN {$prefixExpr} = 'G' THEN {$numericExpr} * 1e9" .
+            " WHEN {$prefixExpr} = 'T' THEN {$numericExpr} * 1e12" .
+            " ELSE {$numericExpr} * 1" .
+            " END)";
+    }
+
+    /**
+     * PHP callback for SQLite's SI_VALUE function.
+     * Extracts the first numeric value with an optional SI prefix and returns the scaled value.
+     *
+     * @param string|null $value The input string
+     * @return float|null The scaled numeric value, or null if no number found
+     */
+    public static function sqliteSiValue(?string $value): ?float
+    {
+        if ($value === null) {
+            return null;
+        }
+
+        // Match a number at the very start (allowing leading whitespace), optionally followed by an SI prefix
+        if (!preg_match('/^\s*(\d+\.?\d*)\s*([pnuµmkKMGT])?/u', $value, $matches)) {
+            return null;
+        }
+
+        $number = (float) $matches[1];
+        $prefix = $matches[2] ?? '';
+
+        if ($prefix === '') {
+            return $number;
+        }
+
+        $multiplier = self::SI_MULTIPLIERS[$prefix] ?? 1.0;
+
+        return $number * $multiplier;
+    }
+}

src/Doctrine/Middleware/SQLiteRegexExtensionMiddlewareDriver.php

@@ -23,6 +23,7 @@ declare(strict_types=1);
 
 namespace App\Doctrine\Middleware;
 
+use App\Doctrine\Functions\SiValueSort;
 use App\Exceptions\InvalidRegexException;
 use Doctrine\DBAL\Driver\Connection;
 use Doctrine\DBAL\Driver\Middleware\AbstractDriverMiddleware;
@@ -51,6 +52,9 @@ class SQLiteRegexExtensionMiddlewareDriver extends AbstractDriverMiddleware
 
                 //Create a new collation for natural sorting
                 $native_connection->sqliteCreateCollation('NATURAL_CMP', strnatcmp(...));
+
+                //Create a function for SI prefix value sorting
+                $native_connection->sqliteCreateFunction('SI_VALUE', SiValueSort::sqliteSiValue(...), 1, \PDO::SQLITE_DETERMINISTIC);
             }
         }
 

src/Settings/BehaviorSettings/PartTableColumns.php

@@ -52,6 +52,8 @@ enum PartTableColumns : string implements TranslatableInterface
     case TAGS = "tags";
     case ATTACHMENTS = "attachments";
 
+    case SI_NAME = "si_name";
+
     case EDA_REFERENCE = "eda_reference";
 
     case EDA_VALUE = "eda_value";
@@ -67,6 +69,7 @@ enum PartTableColumns : string implements TranslatableInterface
             self::NEEDS_REVIEW => 'part.table.needsReview',
             self::MANUFACTURING_STATUS => 'part.table.manufacturingStatus',
             self::MPN => 'part.table.mpn',
+            self::SI_NAME => 'part.table.si_name',
             default => 'part.table.' . $this->value,
         };