Refactor

Refactor into four major components:

1. Common: Things shared among all other components.
2. Lang: P4-language-related components.
3. Runtime: Components required to run a P4 program.
4. Parser: Components for parsing a P4 program from source.

Other components:

1. Macros
2. Tests
3. TreeSitterExtensions: Extra tree sitter functionality

Signed-off-by: Will Hawkins <hawkinsw@obs.cr>

Sources/Common/ProgramTypes.swift

@@ -0,0 +1,99 @@
+// p4rse, Copyright 2026, Will Hawkins
+//
+// This file is part of p4rse.
+//
+// This file is free software: you can redistribute it and/or modify
+// it under the terms of the GNU 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 General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with this program. If not, see <https://www.gnu.org/licenses/>.
+
+
+public class Identifier: CustomStringConvertible, Equatable {
+    var name: String
+
+    public init(name: String) {
+        self.name = name
+    }
+
+    public var description: String {
+        return "\(name)"
+    }
+
+    public static func ==(lhs: Identifier, rhs: Identifier) -> Bool {
+        return lhs.name == rhs.name
+    }
+}
+
+public class Variable: Identifier {
+    var constant: Bool
+    var value: ValueType
+
+    public init(name: String, withValue value: ValueType, isConstant constant: Bool) {
+        self.constant = constant
+        self.value = value
+        super.init(name: name)
+    }
+
+    public override var description: String {
+        return "\(super.description) = \(value) \(constant ? "(constant)" : "")"
+    }
+
+    public var value_type: ValueType {
+        get {
+            value
+        }
+    }
+}
+
+public enum ValueType: CustomStringConvertible, Equatable {
+    case Boolean(Bool)
+    case Int(Int)
+    case String(String)
+
+    public var description: String {
+        switch self {
+            case ValueType.Boolean(let b):
+                return "\(b) of Boolean"
+            case ValueType.Int(let i):
+                return "\(i) of Int"
+            case ValueType.String(let s):
+                return "\(s) of String"
+        }
+    }
+
+    public static func==(lhs: ValueType, rhs: ValueType) -> Bool {
+        switch (lhs,rhs) {
+            case (ValueType.Boolean(let lhsb), ValueType.Boolean(let rhsb)):
+                return lhsb == rhsb
+            case (ValueType.String(let lhsb), ValueType.String(let rhsb)):
+                return lhsb == rhsb
+            case (ValueType.Int(let lhsb), ValueType.Int(let rhsb)):
+                return lhsb == rhsb
+            default: return false
+        }
+    }
+
+}
+
+public struct Value: CustomStringConvertible {
+    public var value_type: ValueType
+
+    public init(withValue value: ValueType) {
+        self.value_type = value
+    }
+    public var description: String {
+        return "\(value_type)"
+    }
+}
+
+public class Packet {
+    public init() {}
+}