add swiftUI code

2025-01-22 14:09:10 +08:00
parent 68e7b7347c
commit 8a99853829
2531 changed files with 486215 additions and 0 deletions
@@ -0,0 +1,78 @@
+/// A thread-unsafe database schema cache
+struct DatabaseSchemaCache {
+    /// A cached value
+    ///
+    /// We cache both hits and misses, because we often query both the temp
+    /// schema and the main schema: not remembering misses would have us
+    /// perform too many database queries.
+    enum Presence<T> {
+        /// Value does not exist in the schema.
+        case missing
+        
+        /// Value exists in the schema.
+        case value(T)
+        
+        var value: T? {
+            switch self {
+            case .missing: return nil
+            case let .value(value): return value
+            }
+        }
+    }
+    
+    var schemaInfo: SchemaInfo?
+    private var tables: [String: Presence<TableInfo>] = [:]
+    private var primaryKeys: [String: Presence<PrimaryKeyInfo>] = [:]
+    private var columns: [String: Presence<[ColumnInfo]>] = [:]
+    private var indexes: [String: Presence<[IndexInfo]>] = [:]
+    private var foreignKeys: [String: Presence<[ForeignKeyInfo]>] = [:]
+    
+    mutating func clear() {
+        tables = [:]
+        primaryKeys = [:]
+        columns = [:]
+        indexes = [:]
+        foreignKeys = [:]
+        schemaInfo = nil
+    }
+    
+    func table(_ table: String) -> Presence<TableInfo>? {
+        tables[table]
+    }
+    
+    mutating func set(tableInfo: Presence<TableInfo>, forTable table: String) {
+        tables[table] = tableInfo
+    }
+    
+    func primaryKey(_ table: String) -> Presence<PrimaryKeyInfo>? {
+        primaryKeys[table]
+    }
+    
+    mutating func set(primaryKey: Presence<PrimaryKeyInfo>, forTable table: String) {
+        primaryKeys[table] = primaryKey
+    }
+    
+    func columns(in table: String) -> Presence<[ColumnInfo]>? {
+        columns[table]
+    }
+    
+    mutating func set(columns: Presence<[ColumnInfo]>, forTable table: String) {
+        self.columns[table] = columns
+    }
+    
+    func indexes(on table: String) -> Presence<[IndexInfo]>? {
+        indexes[table]
+    }
+    
+    mutating func set(indexes: Presence<[IndexInfo]>, forTable table: String) {
+        self.indexes[table] = indexes
+    }
+    
+    func foreignKeys(on table: String) -> Presence<[ForeignKeyInfo]>? {
+        foreignKeys[table]
+    }
+    
+    mutating func set(foreignKeys: Presence<[ForeignKeyInfo]>, forTable table: String) {
+        self.foreignKeys[table] = foreignKeys
+    }
+}