Move logic to extension: Move model files to Shared

Signed-off-by: Roopesh Chander <roop@roopc.net>

1 files changed, 86 insertions, 0 deletions

diff --git a/WireGuard/Shared/Model/IPAddressRange.swift b/WireGuard/Shared/Model/IPAddressRange.swift
new file mode 100644
index 0000000..2fb4a16
--- /dev/null
+++ b/WireGuard/Shared/Model/IPAddressRange.swift
@@ -0,0 +1,86 @@
+// SPDX-License-Identifier: MIT
+// Copyright © 2018 WireGuard LLC. All Rights Reserved.
+
+import Foundation
+import Network
+
+@available(OSX 10.14, iOS 12.0, *)
+struct IPAddressRange {
+    let address: IPAddress
+    var networkPrefixLength: UInt8
+}
+
+// MARK: Converting to and from String
+// For use in the UI
+
+extension IPAddressRange {
+    init?(from string: String) {
+        let endOfIPAddress = string.lastIndex(of: "/") ?? string.endIndex
+        let addressString = String(string[string.startIndex ..< endOfIPAddress])
+        let address: IPAddress
+        if let addr = IPv4Address(addressString) {
+            address = addr
+        } else if let addr = IPv6Address(addressString) {
+            address = addr
+        } else {
+            return nil
+        }
+        let maxNetworkPrefixLength: UInt8 = (address is IPv4Address) ? 32 : 128
+        var networkPrefixLength: UInt8
+        if (endOfIPAddress < string.endIndex) { // "/" was located
+            let indexOfNetworkPrefixLength = string.index(after: endOfIPAddress)
+            guard (indexOfNetworkPrefixLength < string.endIndex) else { return nil }
+            let networkPrefixLengthSubstring = string[indexOfNetworkPrefixLength ..< string.endIndex]
+            guard let npl = UInt8(networkPrefixLengthSubstring) else { return nil }
+            networkPrefixLength = min(npl, maxNetworkPrefixLength)
+        } else {
+            networkPrefixLength = maxNetworkPrefixLength
+        }
+        self.address = address
+        self.networkPrefixLength = networkPrefixLength
+    }
+    func stringRepresentation() -> String {
+        return "\(address)/\(networkPrefixLength)"
+    }
+}
+
+// MARK: Codable
+// For serializing to disk
+
+@available(OSX 10.14, iOS 12.0, *)
+extension IPAddressRange: Codable {
+    public func encode(to encoder: Encoder) throws {
+        var container = encoder.singleValueContainer()
+        let addressDataLength: Int
+        if address is IPv4Address {
+            addressDataLength = 4
+        } else if address is IPv6Address {
+            addressDataLength = 16
+        } else {
+            fatalError()
+        }
+        var data = Data(capacity: addressDataLength + 1)
+        data.append(address.rawValue)
+        data.append(networkPrefixLength)
+        try container.encode(data)
+    }
+    public init(from decoder: Decoder) throws {
+        let container = try decoder.singleValueContainer()
+        var data = try container.decode(Data.self)
+        networkPrefixLength = data.removeLast()
+        let ipAddressFromData: IPAddress? = {
+            switch (data.count) {
+            case 4: return IPv4Address(data)
+            case 16: return IPv6Address(data)
+            default: return nil
+            }
+        }()
+        guard let ipAddress = ipAddressFromData else {
+            throw DecodingError.invalidData
+        }
+        address = ipAddress
+    }
+    enum DecodingError: Error {
+        case invalidData
+    }
+}