Implemented the PrepareURIPathUseCase use case type in the library target.

2025-09-23 15:19:16 +02:00
parent 0d76afb738
commit 2f701ce95e
3 changed files with 283 additions and 0 deletions
@@ -0,0 +1,121 @@
+// ===----------------------------------------------------------------------===
+//
+// This source file is part of the Hummingbird DocC Middleware open source project
+//
+// Copyright (c) 2025 Röck+Cöde VoF. and the Hummingbird DocC Middleware project authors
+// Licensed under the EUPL 1.2 or later.
+//
+// See LICENSE for license information
+// See CONTRIBUTORS for the list of Hummingbird DocC Middleware project authors
+//
+// ===----------------------------------------------------------------------===
+
+import Foundation
+import RegexBuilder
+
+/// A use case that obtains some necessary data from a given URI path, that are essential for routing the documentation contents.
+struct PrepareURIPathUseCase {
+    
+    // MARK: Type aliases
+    
+    /// A pseudo-type that contains the archive name and URI path, plus the resource URI paths used for routing the documentation contents.
+    typealias PreparedURIPaths = (archiveName: String, archivePath: String, resourcePath: String)
+    
+    // MARK: Properties
+    
+    /// A root path that suffixes the documentation resource.
+    private let uriRoot: String
+    
+    // MARK: Initializers
+    
+    /// Initializes this use case.
+    ///
+    /// > important: It is assumed that the `uriRoot` parameter is not empty and that it is prefixed by the `/` character.
+    ///
+    /// - Parameter uriRoot: A root path that prefixes the documentation resource.
+    init(uriRoot: String) {
+        self.uriRoot = uriRoot
+    }
+    
+    // MARK: Functions
+    
+    /// Extracts some necessary data essential for documentation contents routing from a given URI path.
+    ///
+    /// The necessary data to extract from a given URI path is:
+    /// 1. the `DocC` documentation archive name;
+    /// 2. the `DocC` documentation archive URI path;
+    /// 3. the `DocC` documentation resource URI path.
+    ///
+    /// > important: It is assumed that the `uriPath` parameter is a URI path that does not contain any percent encoded strings.
+    ///
+    /// - Parameter uriPath: A URI path to extract the data from.
+    /// - Returns: A pseudo-type that contains the archive' name and URI path, plus the resource URI paths.
+    func callAsFunction(_ uriPath: String) -> PreparedURIPaths? {
+        guard let uriRest = restOfURIPath(from: uriPath) else {
+            return nil
+        }
+        
+        let documentationName = uriRest
+            .split(separator: .forwardSlash)
+            .map(String.init)
+            .first
+
+        let archiveName: String = if let documentationName {
+            documentationName.lowercased()
+        } else {
+            .empty
+        }
+        let archivePath: String = if let documentationName {
+            .init(format: .Format.Path.archive, documentationName)
+        } else {
+            .empty
+        }
+
+        return (archiveName, archivePath, uriRest)
+    }
+    
+}
+
+// MARK: - Helpers
+
+private extension PrepareURIPathUseCase {
+    
+    // MARK: Functions
+    
+    /// Extracts the rest of the URI path from a given URI path against a defined URI root path.
+    ///
+    /// A given URI path is matched against a regular expression, which is generated from a provided URI root path.
+    /// So this function would return either a string that represents a partial URI path, or a `nil` instance depending the result of the match between
+    /// the URI path and the regular expression:
+    /// * A `nil` instance in case there is no match;
+    /// * A `/` string in case there is a perfect match;
+    /// * A partial URI path prefixed with the `/` character in case there is an offset in the match.
+    ///
+    /// - Parameter uriPath: A URI path to get the rest of the URI path from.
+    /// - Returns: A rest of the URI path prefixed by the `/`character  in case where there is any offset path after extracting the root path from the given URI path or not. Otherwise, a `nil` value is returned.
+    func restOfURIPath(from uriPath: String) -> String? {
+        let restReference = Reference(String.self)
+        let uriPattern = Regex {
+            uriRoot
+            Optionally {
+                Capture(as: restReference) {
+                    OneOrMore(.anyNonNewline)
+                } transform: { output in
+                    String(output)
+                }
+            }
+        }
+        
+        guard let matches = uriPath.prefixMatch(of: uriPattern) else {
+            return nil
+        }
+        guard let uriRest = matches.output.1 else {
+            return .forwardSlash
+        }
+        guard uriRest.hasPrefix(String.forwardSlash) else {
+            return .init(format: .Format.Path.root, uriRest)
+        }
+        return uriRest
+    }
+    
+}