// Copyright 2018 the FloatingPanel authors. All rights reserved. MIT license.

import UIKit
import FloatingPanel

/**
 - Attention: `FloatingPanelLayout` must not be applied by the parent view
 controller of a panel. But here `MainViewController` adopts it
 purposely to check if the library prints an appropriate warning.
 */
extension MainViewController: FloatingPanelLayout {
    var position: FloatingPanelPosition { .bottom }
    var initialState: FloatingPanelState { .half }
    var anchors: [FloatingPanelState: FloatingPanelLayoutAnchoring] {
        return [
            .full: FloatingPanelLayoutAnchor(absoluteInset: UIScreen.main.bounds.height == 667.0 ? 18.0 : 16.0, edge: .top, referenceGuide: .safeArea),
            .half: FloatingPanelLayoutAnchor(absoluteInset: 262.0, edge: .bottom, referenceGuide: .safeArea),
            .tip: FloatingPanelLayoutAnchor(absoluteInset: 69.0, edge: .bottom, referenceGuide: .safeArea)
        ]
    }
}

class TopPositionedPanelLayout: FloatingPanelLayout {
    let position: FloatingPanelPosition = .top
    let initialState: FloatingPanelState = .full
    let anchors: [FloatingPanelState : FloatingPanelLayoutAnchoring] = [
        .full: FloatingPanelLayoutAnchor(absoluteInset: 88.0, edge: .bottom, referenceGuide: .safeArea),
        .half: FloatingPanelLayoutAnchor(absoluteInset: 216.0, edge: .top, referenceGuide: .safeArea),
        .tip: FloatingPanelLayoutAnchor(absoluteInset: 44.0, edge: .top, referenceGuide: .safeArea)
    ]
}

class IntrinsicPanelLayout: FloatingPanelBottomLayout {
    override var initialState: FloatingPanelState { .full }
    override var anchors: [FloatingPanelState : FloatingPanelLayoutAnchoring] {
        return [
            .full: FloatingPanelIntrinsicLayoutAnchor(fractionalOffset: 0.0, referenceGuide: .safeArea)
        ]
    }
}

class RemovablePanelLayout: FloatingPanelLayout {
    let position: FloatingPanelPosition = .bottom
    let initialState: FloatingPanelState = .half
    let anchors: [FloatingPanelState : FloatingPanelLayoutAnchoring] = [
            .full: FloatingPanelIntrinsicLayoutAnchor(fractionalOffset: 0.0, referenceGuide: .safeArea),
            .half: FloatingPanelLayoutAnchor(absoluteInset: 130.0, edge: .bottom, referenceGuide: .safeArea)
    ]

    func backdropAlpha(for state: FloatingPanelState) -> CGFloat {
        return 0.3
    }
}

class RemovablePanelLandscapeLayout: FloatingPanelLayout {
    let position: FloatingPanelPosition = .bottom
    let initialState: FloatingPanelState = .full
    let anchors: [FloatingPanelState : FloatingPanelLayoutAnchoring] = [
        .full: FloatingPanelIntrinsicLayoutAnchor(fractionalOffset: 0.0, referenceGuide: .safeArea),
        .half: FloatingPanelLayoutAnchor(absoluteInset: 216.0, edge: .bottom, referenceGuide: .safeArea)
    ]

    func backdropAlpha(for state: FloatingPanelState) -> CGFloat {
        return 0.3
    }
}

class ModalPanelLayout: FloatingPanelLayout {
    let position: FloatingPanelPosition = .bottom
    let initialState: FloatingPanelState = .full
    let anchors: [FloatingPanelState : FloatingPanelLayoutAnchoring] = [
        .full: FloatingPanelIntrinsicLayoutAnchor(absoluteOffset: 0.0, referenceGuide: .safeArea),
    ]

    func backdropAlpha(for state: FloatingPanelState) -> CGFloat {
        return 0.3
    }
}