import UIKit

/// Declarative output from an expanded render strategy.
///
/// Each strategy returns this struct with every behavioral dimension
/// explicitly declared. The parent applies it via a single shared
/// `applyExpandedRenderOutput()` method — no closures, no inout params.
@MainActor
struct ExpandedRenderOutput {
    let renderSignature: Int?
    let renderedText: String?
    let shouldAutoFollow: Bool
    let viewportPolicy: ToolRowViewportPolicy
    let verticalLock: Bool
    let scrollBehavior: ScrollBehavior
    let lineBreakMode: NSLineBreakMode
    let horizontalScroll: Bool
    let deferredHighlight: ToolRowCodeRenderStrategy.DeferredHighlight?
    let invalidateLayout: Bool
    let installAction: InstallAction

    var surface: ExpandedSurface { viewportPolicy.surface }
    var viewportMode: ToolTimelineRowContentView.ExpandedViewportMode { viewportPolicy.viewportMode }

    enum ExpandedSurface: Equatable {
        case label
        case hostedView
        case compactHostedView
        case markdownViewport
    }

    enum ScrollBehavior {
        case followTail
        case resetToTop
        case preserve
    }

    /// Declarative view-installation intent returned by hosted-view strategies
    /// (read-media). The parent interprets this in `applyExpandedRenderOutput`
    /// instead of the strategy calling installation closures directly.
    enum InstallAction {
        case none
        case readMedia(output: String, isError: Bool, filePath: String?, startLine: Int, attachments: [ToolPresentationBuilder.ToolMediaAttachment])
        case audioMessage(text: String, attachmentId: String, mimeType: String, playbackBehavior: AudioPlaybackBehavior?)
        case markdownViewport(
            text: String,
            isStreaming: Bool,
            reviewCommentSelectionRouter: ReviewCommentSelectionRouter?,
            reviewCommentSourceContext: ReviewCommentSourceContext?,
            textSelectionEnabled: Bool
        )
    }
}