"You're banned" error scraping and thematic rounded SwiftUI font (#1187)

* Detect and report "you're banned" error page

* Cleanup

* Round fonts in (SwiftUI) Settings screen when requested by theme

App/View Controllers/LoginViewController.swift

@@ -33,12 +33,12 @@ class LoginViewController: ViewController {
         case awaitingPassword
         case canAttemptLogin
         case attemptingLogin
-        case failedLogin
+        case failedLogin(Error)
     }
 
     fileprivate var state: State = .awaitingUsername {
         didSet {
-            switch(state) {
+            switch state {
             case .awaitingUsername, .awaitingPassword:
                 usernameTextField.isEnabled = true
                 passwordTextField.isEnabled = true
@@ -54,13 +54,23 @@ class LoginViewController: ViewController {
                 nextBarButtonItem.isEnabled = false
                 forgotPasswordButton.isHidden = true
                 activityIndicator.startAnimating()
-            case .failedLogin:
+            case .failedLogin(let error):
                 activityIndicator.stopAnimating()
-                let alert = UIAlertController(title: "Problem Logging In", message: "Double-check your username and password, then try again.", alertActions: [.ok {
+                let title: String
+                let message: String
+                if let error = error as? ServerError, case .banned = error {
+                    // ServerError.banned has actually helpful info to report here.
+                    title = error.localizedDescription
+                    message = error.failureReason ?? ""
+                } else {
+                    title = String(localized: "Problem Logging In")
+                    message = String(localized: "Double-check your username and password, then try again.")
+                }
+                let alert = UIAlertController(title: title, message: message, alertActions: [.ok {
                     self.state = .canAttemptLogin
                     self.passwordTextField.becomeFirstResponder()
                 }])
-                present(alert, animated: true, completion: nil)
+                present(alert, animated: true)
             }
         }
     }
@@ -123,7 +133,9 @@ class LoginViewController: ViewController {
     }
 
     fileprivate func attemptToLogIn() {
-        assert(state == .canAttemptLogin, "unexpected state")
+        if case .canAttemptLogin = state { /* yay */ } else {
+            assertionFailure("unexpected state: \(state)")
+        }
         state = .attemptingLogin
         Task {
             do {
@@ -137,7 +149,7 @@ class LoginViewController: ViewController {
                 completionBlock?(self)
             } catch {
                 Log.e("Could not log in: \(error)")
-                state = .failedLogin
+                state = .failedLogin(error)
             }
         }
     }

AwfulCore/Sources/AwfulCore/Networking/ForumsClient.swift

@@ -100,19 +100,19 @@ public final class ForumsClient {
     }
 
     private var loginCookie: HTTPCookie? {
-        return baseURL
+        baseURL
             .flatMap { urlSession?.configuration.httpCookieStorage?.cookies(for: $0) }?
             .first { $0.name == "bbuserid" }
     }
 
     /// Whether or not a valid, logged-in session exists.
     public var isLoggedIn: Bool {
-        return loginCookie != nil
+        loginCookie != nil
     }
 
     /// When the valid, logged-in session expires.
     public var loginCookieExpiryDate: Date? {
-        return loginCookie?.expiresDate
+        loginCookie?.expiresDate
     }
 
     enum Error: Swift.Error {
@@ -190,13 +190,29 @@ public final class ForumsClient {
         else { throw Error.missingManagedObjectContext }
 
         // Not that we'll parse any JSON from the login attempt, but tacking `json=1` on to `urlString` might avoid pointless server-side rendering.
-        let (data, _) = try await fetch(method: .post, urlString: "account.php?json=1", parameters: [
+        let (data, response) = try await fetch(method: .post, urlString: "account.php?json=1", parameters: [
             "action": "login",
             "username": username,
             "password" : password,
             "next": "/index.php?json=1",
         ])
-        let result = try JSONDecoder().decode(IndexScrapeResult.self, from: data)
+        let result: IndexScrapeResult
+        do {
+            result = try JSONDecoder().decode(IndexScrapeResult.self, from: data)
+        } catch {
+            // We can fail to decode JSON when the server responds with an error as HTML. We may actually be logged in despite the error (e.g. a banned user can "log in" but do basically nothing). However, subsequent launches will crash because we don't actually store the logged-in user's ID. We can avoid the crash by clearing cookies, so we seem logged out.
+            urlSession?.configuration.httpCookieStorage?.removeCookies(since: .distantPast)
+
+            if let error = error as? DecodingError,
+               case .dataCorrupted = error
+            {
+                // Response data was not JSON. Maybe it was a server error delivered as HTML?
+                _ = try parseHTML(data: data, response: response)
+            }
+
+            // We couldn't figure out a more helpful error, so throw the decoding error.
+            throw error
+        }
         let backgroundUser = try await backgroundContext.perform {
             let managed = try result.upsert(into: backgroundContext)
             try backgroundContext.save()
@@ -1255,10 +1271,7 @@ extension URLSessionTask: Cancellable {}
 private typealias ParsedDocument = (document: HTMLDocument, url: URL?)
 
 private func parseHTML(data: Data, response: URLResponse) throws -> ParsedDocument {
-    let contentType: String? = {
-        guard let response = response as? HTTPURLResponse else { return nil }
-        return response.allHeaderFields["Content-Type"] as? String
-    }()
+    let contentType = (response as? HTTPURLResponse)?.allHeaderFields["Content-Type"] as? String
     let document = HTMLDocument(data: data, contentTypeHeader: contentType)
     try checkServerErrors(document)
     return (document: document, url: response.url)
@@ -1282,25 +1295,38 @@ private func workAroundAnnoyingImageBBcodeTagNotMatching(in postbody: HTMLElemen
     }
 }
 
-enum ServerError: LocalizedError {
+public enum ServerError: LocalizedError {
+    case banned(reason: URL?, help: URL?)
     case databaseUnavailable(title: String, message: String)
     case standard(title: String, message: String)
 
-    var errorDescription: String? {
+    public var errorDescription: String? {
         switch self {
+        case .banned:
+            String(localized: "You've Been Banned", bundle: .module)
         case .databaseUnavailable(title: _, message: let message),
              .standard(title: _, message: let message):
-            return message
+            message
+        }
+    }
+
+    public var failureReason: String? {
+        switch self {
+        case .banned:
+            String(localized: "Congratulations! Please visit the Something Awful Forums website to learn why you were banned, to contact a mod or admin, to read the rules, or to reactivate your account.")
+        case .databaseUnavailable, .standard:
+            nil
         }
     }
 }
 
 private func checkServerErrors(_ document: HTMLDocument) throws {
     if let result = try? DatabaseUnavailableScrapeResult(document, url: nil) {
         throw ServerError.databaseUnavailable(title: result.title, message: result.message)
-    }
-    else if let result = try? StandardErrorScrapeResult(document, url: nil) {
+    } else if let result = try? StandardErrorScrapeResult(document, url: nil) {
         throw ServerError.standard(title: result.title, message: result.message)
+    } else if let result = try? BannedScrapeResult(document, url: nil) {
+        throw ServerError.banned(reason: result.reason, help: result.help)
     }
 }
 

AwfulCore/Sources/AwfulCore/Scraping/BannedScrapeResult.swift

@@ -0,0 +1,25 @@
+//  BannedScrapeResult.swift
+//
+//  Copyright 2024 Awful Contributors. CC BY-NC-SA 3.0 US https://github.com/Awful/Awful.app
+
+import HTMLReader
+
+public struct BannedScrapeResult: ScrapeResult {
+    public let help: URL?
+    public let reason: URL?
+
+    public init(_ html: HTMLNode, url: URL?) throws {
+        guard let body = html.firstNode(matchingSelector: "body.banned") else {
+            throw ScrapingError.missingExpectedElement("body.banned")
+        }
+
+        help = body
+            .firstNode(matchingSelector: "a[href*='showthread.php']")
+            .flatMap { $0["href"] }
+            .flatMap { URL(string: $0) }
+        reason = body
+            .firstNode(matchingSelector: "a[href*='banlist.php']")
+            .flatMap { $0["href"] }
+            .flatMap { URL(string: $0) }
+    }
+}

AwfulCore/Tests/AwfulCoreTests/Fixtures/banned.html

@@ -0,0 +1,24 @@
+<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "//www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
+<html xmlns="//www.w3.org/1999/xhtml">
+<head>
+<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
+<title>You've Been Banned!</title>
+<style type="text/css">
+	body { background-color: #000000; text-align:center; font-family:arial, sans-serif; }
+	h1 { font-weight: bold; font-size: xx-large; color: #00FF00; }
+	.style2 { color: #FF0000; }
+	a:link { color: #FF9900; }
+	a:visited { color: #FF3300; }
+	a:active { color: #FFFF00; }
+	</style>
+</head>
+<body id="something_awful" class="banned">
+<h1>CONGRATULATIONS pokeyman!!!</h1>
+<img src="//i.somethingawful.com/images/banned/banned2.jpg" alt="Banned!" width="800" height="800" border="1"></p>
+<p class="style2"><a href="/banlist.php?userid=xxxxxx&amp;actfilt=-1">To check why you were banned, click here.</a></p>
+<p class="style2"><a href="//forums.somethingawful.com/showthread.php?threadid=3809308">To contact a mod or admin, click here.</a></p>
+<p class="style2"><a href="//www.somethingawful.com/forum-rules/forum-rules/">To read the god damn rules, click here.</a></p>
+<p class="style2"><a href="https://store.somethingawful.com/products/unban.php">To reactivate your Something Awful Forums account, please click here.</a></p>
+<a href="/account.php?action=logout&amp;ma=xxxxxxxx">To logout of your worthless banned account, click here.</a>
+</body>
+</html>

AwfulCore/Tests/AwfulCoreTests/Scraping/BannedScrapingTests.swift

@@ -0,0 +1,27 @@
+//  BannedScrapingTests.swift
+//
+//  Copyright 2024 Awful Contributors. CC BY-NC-SA 3.0 US https://github.com/Awful/Awful.app
+
+@testable import AwfulCore
+import XCTest
+
+final class BannedScrapingTests: XCTestCase {
+    override class func setUp() {
+        super.setUp()
+        testInit()
+    }
+
+    func testBanned() throws {
+        let scraped = try scrapeHTMLFixture(BannedScrapeResult.self, named: "banned")
+
+        let help = try XCTUnwrap(scraped.help)
+        XCTAssertTrue(help.path.hasPrefix("/showthread.php"))
+
+        let reason = try XCTUnwrap(scraped.reason)
+        XCTAssertTrue(reason.path.hasPrefix("/banlist.php"))
+    }
+
+    func testNotBanned() throws {
+        XCTAssertThrowsError(try scrapeHTMLFixture(BannedScrapeResult.self, named: "forumdisplay"))
+    }
+}

AwfulExtensions/Sources/SwiftUI/Backports.swift

@@ -5,6 +5,15 @@
 import SwiftUI
 
 public extension Backport where Content: View {
+
+    @ViewBuilder func fontDesign(_ design: Font.Design?) -> some View {
+        if #available(iOS 16.1, *) {
+            content.fontDesign(design)
+        } else {
+            content
+        }
+    }
+
     /// Sets the font weight of the text in this view.
     @ViewBuilder func fontWeight(_ weight: Font.Weight?) -> some View {
         if #available(iOS 16, *) {

AwfulSettingsUI/Sources/AwfulSettingsUI/SettingsView.swift

@@ -286,6 +286,7 @@ public struct SettingsView: View {
             }
             .section()
         }
+        .backport.fontDesign(theme.roundedFonts ? .rounded : nil)
         .foregroundStyle(theme[color: "listText"]!)
         .tint(theme[color: "tint"]!)
         .backport.scrollContentBackground(.hidden)