Add mode, bring in definition/patch queries

src/Configuration.php

@@ -24,6 +24,9 @@ class Configuration
     /** @var array|null Options to use for connections (driver-specific) */
     public static ?array $options = null;
 
+    /** @var Mode|null The mode in which the library is operating (filled after first connection if not configured) */
+    public static ?Mode $mode = null;
+
     /**
      * Retrieve a new connection to the database
      *
@@ -38,8 +41,15 @@ class Configuration
         $db = new PDO(self::$pdoDSN, $_ENV['PDO_DOC_USERNAME'] ?? self::$username,
             $_ENV['PDO_DOC_PASSWORD'] ?? self::$password, self::$options);
 
-        // TODO: determine driver, set mode for other queries
-        echo $db->getAttribute(PDO::ATTR_DRIVER_NAME);
+        if (is_null(self::$mode)) {
+            $driver = $db->getAttribute(PDO::ATTR_DRIVER_NAME);
+            self::$mode = match ($driver) {
+                'pgsql'  => Mode::PgSQL,
+                'sqlite' => Mode::SQLite,
+                default  => throw new DocumentException(
+                    "Unsupported driver $driver: this library currently supports PostgreSQL and SQLite")
+            };
+        }
         return $db;
     }
 }

src/Mode.php

@@ -0,0 +1,15 @@
+<?php declare(strict_types=1);
+
+namespace BitBadger\PDODocument;
+
+/**
+ * The mode for queries generated by the library
+ */
+enum Mode
+{
+    /** Storing documents in a PostgreSQL database */
+    case PgSQL;
+
+    /** Storing documents in a SQLite database */
+    case SQLite;
+}

src/Query/Definition.php

@@ -3,6 +3,8 @@
 namespace BitBadger\PDODocument\Query;
 
 use BitBadger\PDODocument\Configuration;
+use BitBadger\PDODocument\DocumentException;
+use BitBadger\PDODocument\Mode;
 
 /**
  * Queries to define tables and indexes
@@ -13,11 +15,16 @@ class Definition
      * SQL statement to create a document table
      *
      * @param string $name The name of the table (including schema, if applicable)
-     * @param string $dataType The data type used for the document column
      * @return string The CREATE TABLE statement for the document table
+     * @throws DocumentException If the database mode has not been set
      */
-    public static function ensureTableFor(string $name, string $dataType): string
+    public static function ensureTable(string $name): string
     {
+        $dataType = match (Configuration::$mode) {
+            Mode::PgSQL  => 'JSONB',
+            Mode::SQLite => 'TEXT',
+            default      => throw new DocumentException('Database mode not set; cannot make create table statement')
+        };
         return "CREATE TABLE IF NOT EXISTS $name (data $dataType NOT NULL)";
     }
 

src/Query/Patch.php

@@ -0,0 +1,59 @@
+<?php declare(strict_types=1);
+
+namespace BitBadger\PDODocument\Query;
+
+use BitBadger\PDODocument\Configuration;
+use BitBadger\PDODocument\DocumentException;
+use BitBadger\PDODocument\Field;
+use BitBadger\PDODocument\Mode;
+use BitBadger\PDODocument\Query;
+
+/**
+ * Queries to perform partial updates on documents
+ */
+class Patch
+{
+    /**
+     * Create an UPDATE statement to patch documents
+     *
+     * @param string $tableName The name of the table in which documents should be patched
+     * @param string $whereClause The body of the WHERE clause to use in the UPDATE statement
+     * @return string The UPDATE statement to perform the patch
+     * @throws DocumentException If the database mode has not been set
+     */
+    public static function update(string $tableName, string $whereClause): string
+    {
+        $setValue = match (Configuration::$mode) {
+            Mode::PgSQL  => 'data || @data',
+            Mode::SQLite => 'json_patch(data, json(@data))',
+            default      => throw new DocumentException('Database mode not set; cannot make patch statement')
+        };
+        return "UPDATE $tableName SET data = $setValue WHERE $whereClause";
+    }
+
+    /**
+     * Query to patch (partially update) a document by its ID
+     *
+     * @param string $tableName The name of the table in which a document should be patched
+     * @return string The query to patch a document by its ID
+     * @throws DocumentException If the database mode has not been set
+     */
+    public static function byId(string $tableName): string
+    {
+        return self::update($tableName, Query::whereById());
+    }
+
+    /**
+     * Query to patch (partially update) a document via a comparison on a JSON field
+     *
+     * @param string $tableName The name of the table in which documents should be patched
+     * @param array|Field[] $field The field comparison to match
+     * @param string $conjunction How to handle multiple conditions (optional; defaults to `AND`)
+     * @return string The query to patch documents via field comparison
+     * @throws DocumentException If the database mode has not been set
+     */
+    public static function byFields(string $tableName, array $field, string $conjunction = 'AND'): string
+    {
+        return self::update($tableName, Query::whereByFields($field, $conjunction));
+    }
+}