Tools/SwiftBrowser/Source/ViewModel/NavigationDecider.swift

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//
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// 1. Redistributions of source code must retain the above copyright
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import Foundation
import WebKit
@_spi(Private) import _WebKit_SwiftUI

@MainActor
final class NavigationDecider: WebPage.NavigationDeciding {
    weak var owner: BrowserViewModel? = nil

    func decidePolicy(for action: WebPage.NavigationAction, preferences: inout WebPage.NavigationPreferences) async -> WKNavigationActionPolicy {
        if action.shouldPerformDownload {
            return .download
        }

        if action.modifierFlags.contains(.command) {
            owner?.currentOpenRequest = .init(request: action.request)
            return .cancel
        }

        return .allow
    }

    func decidePolicy(for response: WebPage.NavigationResponse) async -> WKNavigationResponsePolicy {
        response.canShowMimeType && !response.response.hasAttachment ? .allow : .download
    }
}