Resolve providers correctly

Sources/apk/Index/ApkIndexProvides.swift

@@ -1,12 +1,60 @@
 /*
- * darwin-apk © 2024 Gay Pizza Specifications
+ * darwin-apk © 2024, 2025 Gay Pizza Specifications
  * SPDX-License-Identifier: Apache-2.0
  */
 
-public struct ApkIndexProvides: Hashable, Sendable {
-  let name: String
+import Foundation
 
-  init(requirement: ApkVersionRequirement) {
-    self.name = requirement.name
+public enum ApkIndexProvides: Hashable, Sendable {
+  case any(name: String)
+  case specific(name: String, version: String)
+}
+
+extension ApkIndexProvides {
+  init(requirement: ApkVersionRequirement) throws(ProvidesError) {
+    self = switch requirement.versionSpec {
+    case .any(invert: false):
+      .any(name: requirement.name)
+    case .constraint(invert: false, op: .equals, let version):
+      .specific(name: requirement.name, version: version)
+    default:
+      throw .badConstraint
+    }
+  }
+
+  func satisfies(_ requirement: ApkVersionRequirement) -> Bool {
+    switch self {
+    case .any(let name):
+      return requirement.name == name
+    case .specific(let name, let version):
+      return requirement.name == name &&
+        requirement.versionSpec.satisfied(by: version)
+    }
+  }
+
+  enum ProvidesError: Error, LocalizedError {
+    case badConstraint
+
+    var errorDescription: String? {
+      switch self {
+      case .badConstraint: "Invalid constraint type, must only be equals"
+      }
+    }
+  }
+}
+
+extension ApkIndexProvides: CustomStringConvertible {
+  public var description: String {
+    switch self {
+    case .any(let name): name
+    case .specific(let name, let version): "\(name)=\(version)"
+    }
+  }
+
+  public var name: String {
+    switch self {
+    case .any(let name): name
+    case .specific(let name, _): name
+    }
   }
 }