Refactor peerID - 1/n: Add PeerID + Tests (#688)

* Unify SHA256 hash and hex usages * Refactor `peerID` - 1/n: Add `PeerID` + Tests
2026-07-25 01:45:20 +00:00 · 2025-09-30 12:49:36 +02:00
parent 78fb3f1bf6
commit bf712a0610
2 changed files with 563 additions and 0 deletions
@@ -0,0 +1,177 @@
+//
+// PeerID.swift
+// bitchat
+//
+// This is free and unencumbered software released into the public domain.
+// For more information, see <https://unlicense.org>
+//
+
+import Foundation
+
+struct PeerID: Equatable, Hashable {
+    enum Prefix: String, CaseIterable {
+        /// When no prefix is provided
+        case empty = ""
+        /// `"mesh:"`
+        case mesh = "mesh:"
+        /// `"name:"`
+        case name = "name:"
+        /// `"noise:"` (+ 64 characters hex)
+        case noise = "noise:"
+        /// `"nostr_"` (+ 16 characters hex)
+        case geoDM = "nostr_"
+        /// `"nostr:"` (+ 8 characters hex)
+        case geoChat = "nostr:"
+    }
+    
+    let prefix: Prefix
+    
+    /// Returns the actual value without any prefix
+    let bare: String
+    
+    /// Returns the full `id` value by combining `(prefix + bare)`
+    var id: String { prefix.rawValue + bare }
+    
+    // Private so the callers have to go through a convenience init
+    private init(prefix: Prefix, bare: any StringProtocol) {
+        self.prefix = prefix
+        self.bare = String(bare)
+    }
+}
+
+// MARK: - Convenience Inits
+
+extension PeerID {
+    /// Convenience init to create GeoDM PeerID by appending `"nostr_"` to the first 16 characters of `pubKey`
+    init(nostr_ pubKey: String) {
+        self.init(prefix: .geoDM, bare: pubKey.prefix(TransportConfig.nostrConvKeyPrefixLength))
+    }
+    
+    /// Convenience init to create GeoChat PeerID by appending `"nostr:"` to the first 8 characters of `pubKey`
+    init(nostr pubKey: String) {
+        self.init(prefix: .geoChat, bare: pubKey.prefix(TransportConfig.nostrShortKeyDisplayLength))
+    }
+    
+    /// Convenience init to create PeerID from String/Substring by splitting it into prefix and bare parts
+    init(str: any StringProtocol) {
+        if let prefix = Prefix.allCases.first(where: { $0 != .empty && str.hasPrefix($0.rawValue) }) {
+            self.init(prefix: prefix, bare: String(str).dropFirst(prefix.rawValue.count))
+        } else {
+            self.init(prefix: .empty, bare: str)
+        }
+    }
+    
+    /// Convenience init to create PeerID by converting Data to String
+    init?(data: Data) {
+        guard let str = String(data: data, encoding: .utf8) else { return nil }
+        self.init(str: str)
+    }
+}
+
+// MARK: - Noise Public Key Helpers
+
+extension PeerID {
+    /// Derive the stable 16-hex peer ID from a Noise static public key
+    init(publicKey: Data) {
+        self.init(str: publicKey.sha256Fingerprint().prefix(16))
+    }
+    
+    /// Returns a 16-hex short peer ID derived from a 64-hex Noise public key if needed
+    func toShort() -> PeerID {
+        if let noiseKey {
+            return PeerID(publicKey: noiseKey)
+        }
+        return self
+    }
+}
+
+// MARK: - Codable
+
+extension PeerID: Codable {
+    init(from decoder: any Decoder) throws {
+        self.init(str: try decoder.singleValueContainer().decode(String.self))
+    }
+    
+    func encode(to encoder: any Encoder) throws {
+        var container = encoder.singleValueContainer()
+        try container.encode(id)
+    }
+}
+
+// MARK: - Helpers
+
+extension PeerID {
+    var isEmpty: Bool {
+        id.isEmpty
+    }
+    
+    /// Returns true if `id` starts with "`nostr:`"
+    var isGeoChat: Bool {
+        prefix == .geoChat
+    }
+    
+    /// Returns true if `id` starts with "`nostr_`"
+    var isGeoDM: Bool {
+        prefix == .geoDM
+    }
+    
+    func toPercentEncoded() -> String {
+        id.addingPercentEncoding(withAllowedCharacters: .urlPathAllowed) ?? id
+    }
+}
+
+// MARK: - Validation
+
+extension PeerID {
+    private enum Constants {
+        static let maxIDLength = 64
+        static let hexIDLength = 16 // 8 bytes = 16 hex chars
+    }
+    
+    /// Validates a peer ID from any source (short 16-hex, full 64-hex, or internal alnum/-/_ up to 64)
+    var isValid: Bool {
+        if prefix != .empty {
+            return PeerID(str: bare).isValid
+        }
+        
+        // Accept short routing IDs (exact 16-hex) or Full Noise key hex (exact 64-hex)
+        if isShort || isNoiseKeyHex {
+            return true
+        }
+        
+        // If length equals short or full but isn't valid hex, reject
+        if id.count == Constants.hexIDLength || id.count == Constants.maxIDLength {
+            return false
+        }
+        
+        // Internal format: alphanumeric + dash/underscore up to 63 (not 16 or 64)
+        let validCharset = CharacterSet.alphanumerics.union(CharacterSet(charactersIn: "-_"))
+        return !id.isEmpty &&
+                id.count < Constants.maxIDLength &&
+                id.rangeOfCharacter(from: validCharset.inverted) == nil
+    }
+    
+    /// Short routing IDs (exact 16-hex)
+    var isShort: Bool {
+        id.count == Constants.hexIDLength && Data(hexString: id) != nil
+    }
+    
+    /// Full Noise key hex (exact 64-hex)
+    var isNoiseKeyHex: Bool {
+        noiseKey != nil
+    }
+    
+    /// Full Noise key (exact 64-hex) as Data
+    var noiseKey: Data? {
+        guard id.count == Constants.maxIDLength else { return nil }
+        return Data(hexString: id)
+    }
+}
+
+// MARK: - Comparable
+
+extension PeerID: Comparable {
+    static func < (lhs: PeerID, rhs: PeerID) -> Bool {
+        lhs.id < rhs.id
+    }
+}
@@ -0,0 +1,386 @@
+//
+// PeerIDTests.swift
+// bitchatTests
+//
+// This is free and unencumbered software released into the public domain.
+// For more information, see <https://unlicense.org>
+//
+
+import XCTest
+@testable import bitchat
+
+final class PeerIDTests: XCTestCase {
+    
+    private let hex16 = "0011223344556677"
+    private let hex64 = "00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff"
+    
+    private let encoder: JSONEncoder = {
+        var encoder = JSONEncoder()
+        encoder.outputFormatting = [.sortedKeys]
+        return encoder
+    }()
+    
+    // MARK: - Empty prefix
+    
+    func test_init_empty_prefix_with16() {
+        let peerID = PeerID(str: hex16)
+        XCTAssertEqual(peerID.id, hex16)
+        XCTAssertEqual(peerID.bare, hex16)
+        XCTAssertEqual(peerID.prefix, .empty)
+    }
+    
+    func test_init_empty_prefix_with64() {
+        let peerID = PeerID(str: hex64)
+        XCTAssertEqual(peerID.id, hex64)
+        XCTAssertEqual(peerID.bare, hex64)
+        XCTAssertEqual(peerID.prefix, .empty)
+    }
+    
+    // MARK: - Mesh prefix
+    
+    func test_init_mesh_prefix_with16() {
+        let str = "mesh:" + hex16
+        let peerID = PeerID(str: str)
+        XCTAssertEqual(peerID.id, str)
+        XCTAssertEqual(peerID.bare, hex16)
+        XCTAssertEqual(peerID.prefix, .mesh)
+    }
+    
+    func test_init_mesh_prefix_with64() {
+        let str = "mesh:" + hex64
+        let peerID = PeerID(str: str)
+        XCTAssertEqual(peerID.id, str)
+        XCTAssertEqual(peerID.bare, hex64)
+        XCTAssertEqual(peerID.prefix, .mesh)
+    }
+    
+    // MARK: - Name prefix
+    
+    func test_init_name_prefix() {
+        let str = "name:some_name"
+        let peerID = PeerID(str: str)
+        XCTAssertEqual(peerID.id, str)
+        XCTAssertEqual(peerID.bare, "some_name")
+        XCTAssertEqual(peerID.prefix, .name)
+    }
+    
+    // MARK: - Noise prefix
+    
+    func test_init_noise_prefix_with16() {
+        let str = "noise:" + hex16
+        let peerID = PeerID(str: str)
+        XCTAssertEqual(peerID.id, str)
+        XCTAssertEqual(peerID.bare, hex16)
+        XCTAssertEqual(peerID.prefix, .noise)
+    }
+    
+    func test_init_noise_prefix_with64() {
+        let str = "noise:" + hex64
+        let peerID = PeerID(str: str)
+        XCTAssertEqual(peerID.id, str)
+        XCTAssertEqual(peerID.bare, hex64)
+        XCTAssertEqual(peerID.prefix, .noise)
+    }
+    
+    // MARK: - GeoDM prefix
+    
+    func test_init_geoDM_prefix_with16() {
+        let str = "nostr_" + hex16
+        let peerID = PeerID(str: str)
+        XCTAssertEqual(peerID.id, str)
+        XCTAssertEqual(peerID.bare, hex16)
+        XCTAssertEqual(peerID.prefix, .geoDM)
+    }
+    
+    func test_init_geoDM_prefix_with64() {
+        let str = "nostr_" + hex64
+        let peerID = PeerID(str: str)
+        XCTAssertEqual(peerID.id, str)
+        XCTAssertEqual(peerID.bare, hex64)
+        XCTAssertEqual(peerID.prefix, .geoDM)
+    }
+    
+    // MARK: - GeoChat prefix
+    
+    func test_init_geoChat_prefix_with16() {
+        let str = "nostr:" + hex16
+        let peerID = PeerID(str: str)
+        XCTAssertEqual(peerID.id, str)
+        XCTAssertEqual(peerID.bare, hex16)
+        XCTAssertEqual(peerID.prefix, .geoChat)
+    }
+    
+    func test_init_geoChat_prefix_with64() {
+        let str = "nostr:" + hex64
+        let peerID = PeerID(str: str)
+        XCTAssertEqual(peerID.id, str)
+        XCTAssertEqual(peerID.bare, hex64)
+        XCTAssertEqual(peerID.prefix, .geoChat)
+    }
+    
+    // MARK: - Edge cases
+    
+    func test_init_with_unknown_prefix() {
+        let str = "unknown:" + hex16
+        let peerID = PeerID(str: str)
+        // Falls back to .empty
+        XCTAssertEqual(peerID.id, str)
+        XCTAssertEqual(peerID.bare, str)
+        XCTAssertEqual(peerID.prefix, .empty)
+    }
+    
+    func test_init_with_only_prefix_no_bare() {
+        let str = "mesh:"
+        let peerID = PeerID(str: str)
+        XCTAssertEqual(peerID.id, str)
+        XCTAssertEqual(peerID.bare, "")
+        XCTAssertEqual(peerID.prefix, .mesh)
+    }
+    
+    // MARK: - init?(data:)
+    
+    func test_init_data_valid_utf8() {
+        let peerID = PeerID(data: Data(hex16.utf8))
+        XCTAssertNotNil(peerID)
+        XCTAssertEqual(peerID?.bare, hex16)
+        XCTAssertEqual(peerID?.prefix, .empty)
+    }
+    
+    func test_init_data_invalid_utf8() {
+        // Random invalid UTF8
+        let bytes: [UInt8] = [0xFF, 0xFE, 0xFA]
+        let peerID = PeerID(data: Data(bytes))
+        XCTAssertNil(peerID)
+    }
+    
+    // MARK: - init(str: Substring)
+    
+    func test_init_substring() {
+        let substring = hex64.prefix(16)
+        let peerID = PeerID(str: substring)
+        XCTAssertEqual(peerID.id, String(substring))
+        XCTAssertEqual(peerID.bare, String(substring))
+        XCTAssertEqual(peerID.prefix, .empty)
+    }
+    
+    // MARK: - init(nostr_ pubKey:)
+    
+    func test_init_nostrUnderscore_pubKey() {
+        let pubKey = hex64
+        let peerID = PeerID(nostr_: pubKey)
+        XCTAssertEqual(peerID.id, "nostr_\(pubKey.prefix(TransportConfig.nostrConvKeyPrefixLength))")
+        XCTAssertEqual(peerID.bare, String(pubKey.prefix(TransportConfig.nostrConvKeyPrefixLength)))
+        XCTAssertEqual(peerID.prefix, .geoDM)
+    }
+    
+    // MARK: - init(nostr pubKey:)
+    
+    func test_init_nostr_pubKey() {
+        let pubKey = hex64
+        let peerID = PeerID(nostr: pubKey)
+        XCTAssertEqual(peerID.id, "nostr:\(pubKey.prefix(TransportConfig.nostrShortKeyDisplayLength))")
+        XCTAssertEqual(peerID.bare, String(pubKey.prefix(TransportConfig.nostrShortKeyDisplayLength)))
+        XCTAssertEqual(peerID.prefix, .geoChat)
+    }
+    
+    // MARK: - init(publicKey:)
+    
+    func test_init_publicKey_derivesFingerprint() {
+        let publicKey = Data(hex64.utf8)
+        let expected = publicKey.sha256Fingerprint().prefix(16)
+        let peerID = PeerID(publicKey: publicKey)
+        XCTAssertEqual(peerID.bare, String(expected))
+        XCTAssertEqual(peerID.prefix, .empty)
+    }
+    
+    // MARK: - toShort()
+    
+    func test_toShort_whenNoiseKeyExists() {
+        let peerID = PeerID(str: hex64)
+        let short = peerID.toShort()
+        
+        // `toShort()` should derive 16-hex peerID
+        let expected = Data(hexString: hex64)!.sha256Fingerprint().prefix(16)
+        
+        XCTAssertEqual(short.bare, String(expected))
+        XCTAssertEqual(short.prefix, .empty)
+    }
+    
+    func test_toShort_whenNoNoiseKey() {
+        let peerID = PeerID(str: "some_random_key")
+        let short = peerID.toShort()
+        XCTAssertEqual(short, peerID) // unchanged
+    }
+
+    
+    // MARK: - Codable
+
+    func test_codable_emptyPrefix() throws {
+        struct Dummy: Codable, Equatable {
+            let name: String
+            let peerID: PeerID
+        }
+        
+        let str = "aabbccddeeff0011"
+        let jsonString = "{\"name\":\"some name\",\"peerID\":\"\(str)\"}"
+        
+        let decoded = try JSONDecoder().decode(Dummy.self, from: Data(jsonString.utf8))
+        XCTAssertEqual(decoded.peerID, PeerID(str: str))
+        
+        let encoded = try encoder.encode(decoded)
+        XCTAssertEqual(String(data: encoded, encoding: .utf8), jsonString)
+    }
+
+    func test_codable_withPrefix() throws {
+        struct Dummy: Codable, Equatable {
+            let peerID: PeerID
+        }
+        
+        let str = "nostr_\(hex16)"
+        let jsonString = "{\"peerID\":\"\(str)\"}"
+        
+        let decoded = try JSONDecoder().decode(Dummy.self, from: Data(jsonString.utf8))
+        XCTAssertEqual(decoded.peerID, PeerID(str: str))
+        XCTAssertEqual(decoded.peerID.bare, hex16)
+        XCTAssertEqual(decoded.peerID.prefix, .geoDM)
+        
+        let encoded = try encoder.encode(decoded)
+        XCTAssertEqual(String(data: encoded, encoding: .utf8), jsonString)
+    }
+
+    func test_codable_multiplePrefixes() throws {
+        // Loop across all Prefix cases (except .empty since already tested)
+        for prefix in PeerID.Prefix.allCases where prefix != .empty {
+            let bare = hex16
+            let str = prefix.rawValue + bare
+            
+            let decoded = try JSONDecoder().decode(PeerID.self, from: Data("\"\(str)\"".utf8))
+            XCTAssertEqual(decoded.prefix, prefix)
+            XCTAssertEqual(decoded.bare, bare)
+            
+            let encoded = try encoder.encode(decoded)
+            XCTAssertEqual(String(data: encoded, encoding: .utf8), "\"\(str)\"")
+        }
+    }
+    
+    // MARK: - Comparable
+    
+    func test_comparable_sorting_and_equality() {
+        let p1 = PeerID(str: "aaa")
+        let p2 = PeerID(str: "bbb")
+        let p3 = PeerID(str: "bbb")
+        
+        XCTAssertTrue(p1 < p2)
+        XCTAssertFalse(p2 < p1)
+        XCTAssertEqual(p2, p3)
+        
+        let sorted = [p2, p1].sorted()
+        XCTAssertEqual(sorted, [p1, p2])
+    }
+    
+    // MARK: - Computed properties
+    
+    func test_isEmpty_true_and_false() {
+        XCTAssertTrue(PeerID(str: "").isEmpty)
+        XCTAssertFalse(PeerID(str: "abc").isEmpty)
+    }
+    
+    func test_isGeoChat() {
+        XCTAssertTrue(PeerID(str: "nostr:abcdef").isGeoChat)
+        XCTAssertFalse(PeerID(str: "nostr_abcdef").isGeoChat) // different prefix
+    }
+    
+    func test_isGeoDM() {
+        XCTAssertTrue(PeerID(str: "nostr_abcdef").isGeoDM)
+        XCTAssertFalse(PeerID(str: "nostr:abcdef").isGeoDM)
+    }
+    
+    func test_toPercentEncoded() {
+        let peerID = PeerID(str: "name:some value/with spaces?")
+        let encoded = peerID.toPercentEncoded()
+        // spaces and ? should be percent-encoded in urlPathAllowed
+        XCTAssertEqual(encoded, "name%3Asome%20value/with%20spaces%3F")
+    }
+    
+    // MARK: - Validation
+    
+    func test_accepts_short_hex_peer_id() {
+        XCTAssertTrue(PeerID(str: "0011223344556677").isValid)
+        XCTAssertTrue(PeerID(str: "aabbccddeeff0011").isValid)
+    }
+    
+    func test_accepts_full_noise_key_hex() {
+        let hex64 = String(repeating: "ab", count: 32) // 64 hex chars
+        XCTAssertTrue(PeerID(str: hex64).isValid)
+    }
+    
+    func test_accepts_internal_alnum_dash_underscore() {
+        XCTAssertTrue(PeerID(str: "peer_123-ABC").isValid)
+        XCTAssertTrue(PeerID(str: "nostr_user_01").isValid)
+    }
+    
+    func test_rejects_invalid_characters() {
+        XCTAssertFalse(PeerID(str: "peer!@#").isValid)
+        XCTAssertFalse(PeerID(str: "gggggggggggggggg").isValid) // not hex for short form
+    }
+    
+    func test_rejects_too_long() {
+        let tooLong = String(repeating: "a", count: 65)
+        XCTAssertFalse(PeerID(str: tooLong).isValid)
+    }
+    
+    func test_isShort() {
+        XCTAssertTrue(PeerID(str: hex16).isShort)
+        XCTAssertFalse(PeerID(str: "abcd").isShort) // wrong length
+    }
+    
+    func test_isNoiseKeyHex_and_noiseKey() {
+        let hex64 = String(repeating: "ab", count: 32) // 64 chars valid hex
+        let peerID = PeerID(str: hex64)
+        XCTAssertTrue(peerID.isNoiseKeyHex)
+        XCTAssertNotNil(peerID.noiseKey)
+        
+        let bad = String(repeating: "z", count: 64) // invalid hex
+        let badPeerID = PeerID(str: bad)
+        XCTAssertFalse(badPeerID.isNoiseKeyHex)
+        XCTAssertNil(badPeerID.noiseKey)
+    }
+    
+    func test_prefixes() {
+        let hex64 = String(repeating: "a", count: 64)
+        XCTAssertTrue(PeerID(str: "noise:\(hex64)").isValid)
+        XCTAssertTrue(PeerID(str: "nostr:\(hex64)").isValid)
+        XCTAssertTrue(PeerID(str: "nostr_\(hex64)").isValid)
+
+        let hex63 = String(repeating: "a", count: 63)
+        XCTAssertTrue(PeerID(str: "noise:\(hex63)").isValid)
+        XCTAssertTrue(PeerID(str: "nostr:\(hex63)").isValid)
+        XCTAssertTrue(PeerID(str: "nostr_\(hex63)").isValid)
+
+        let hex16 = String(repeating: "a", count: 16)
+        XCTAssertTrue(PeerID(str: "noise:\(hex16)").isValid)
+        XCTAssertTrue(PeerID(str: "nostr:\(hex16)").isValid)
+        XCTAssertTrue(PeerID(str: "nostr_\(hex16)").isValid)
+
+        let hex8 = String(repeating: "a", count: 8)
+        XCTAssertTrue(PeerID(str: "noise:\(hex8)").isValid)
+        XCTAssertTrue(PeerID(str: "nostr:\(hex8)").isValid)
+        XCTAssertTrue(PeerID(str: "nostr_\(hex8)").isValid)
+
+        let mesh = "mesh:abcdefg"
+        XCTAssertTrue(PeerID(str: "name:\(mesh)").isValid)
+
+        let name = "name:some_name"
+        XCTAssertTrue(PeerID(str: "name:\(name)").isValid)
+
+        let badName = "name:bad:name"
+        XCTAssertFalse(PeerID(str: "name:\(badName)").isValid)
+
+        // Too long
+        let hex65 = String(repeating: "a", count: 65)
+        XCTAssertFalse(PeerID(str: "noise:\(hex65)").isValid)
+        XCTAssertFalse(PeerID(str: "nostr:\(hex65)").isValid)
+        XCTAssertFalse(PeerID(str: "nostr_\(hex65)").isValid)
+    }
+}
+