import SwiftUI

/// Short faded curve under the compact source bubble in a collapsed reply.
struct ReplyThreadCurve: Shape {
    let sourceDirection: ChatMessage.Direction

    func path(in rect: CGRect) -> Path {
        var path = Path()
        if sourceDirection == .incoming {
            path.move(to: CGPoint(x: rect.minX, y: rect.minY))
            path.addCurve(
                to: CGPoint(x: rect.maxX, y: rect.maxY),
                control1: CGPoint(x: rect.minX + 5, y: rect.maxY * 0.78),
                control2: CGPoint(x: rect.midX, y: rect.maxY)
            )
        } else {
            path.move(to: CGPoint(x: rect.maxX, y: rect.minY))
            path.addCurve(
                to: CGPoint(x: rect.minX, y: rect.maxY),
                control1: CGPoint(x: rect.maxX - 5, y: rect.maxY * 0.78),
                control2: CGPoint(x: rect.midX, y: rect.maxY)
            )
        }
        return path
    }
}

/// Bracket displayed beside a source message and several replies in focus mode.
struct ReplyThreadBracket: Shape {
    let opensToTrailing: Bool

    func path(in rect: CGRect) -> Path {
        let edgeX = opensToTrailing ? rect.maxX : rect.minX
        let spineX = opensToTrailing ? rect.minX : rect.maxX
        let radius = min(26, rect.width)
        var path = Path()

        path.move(to: CGPoint(x: edgeX, y: rect.minY))
        path.addCurve(
            to: CGPoint(x: spineX, y: rect.minY + radius),
            control1: CGPoint(x: spineX, y: rect.minY),
            control2: CGPoint(x: spineX, y: rect.minY + radius * 0.45)
        )
        path.addLine(to: CGPoint(x: spineX, y: rect.maxY - radius))
        path.addCurve(
            to: CGPoint(x: edgeX, y: rect.maxY),
            control1: CGPoint(x: spineX, y: rect.maxY - radius * 0.45),
            control2: CGPoint(x: spineX, y: rect.maxY)
        )
        return path
    }
}