//
//  AutoLayout_UIView.swift
//  AutoLayoutSwiftDemo
//
//  Created by Johnhao on 2022/1/6.
//

import UIKit

// MARK: - AutoLayout
extension UIView {
    // MARK: - Private
    private enum Key {
        /// 存储约束key
        internal static var lastConstraint = "lastConstraint"
        /// 存储约束key
        internal static var constraints = "constraints"
        /// jhLayoutChain
        internal static var jhLayoutChain = "jhLayoutChain"
        /// collapsed
        internal static var collapsed = "collapsed"
        /// autoCollapsed
        internal static var autoCollapse = "autoCollapse"
        /// hiddenCollapsed
        internal static var hiddenCollapse = "hiddenCollapse"
    }
    
    /// 所有的约束
    private var jh_allConstraints: [NSLayoutConstraint] {
        get {
            jh_layoutConstraints.values.compactMap { $0 }
        }
    }
    
    /// 所有约束key-value
    private var jh_layoutConstraints: [String: NSLayoutConstraint] {
        get {
            guard let constraints = objc_getAssociatedObject(self, &Key.constraints) as? [String: NSLayoutConstraint] else {
                
                let constraints = [String: NSLayoutConstraint]()
                objc_setAssociatedObject(self,  &Key.constraints, constraints, .OBJC_ASSOCIATION_RETAIN_NONATOMIC)
                return constraints
            }
            return constraints
        }
        
        set {
            objc_setAssociatedObject(self,  &Key.constraints, newValue, .OBJC_ASSOCIATION_RETAIN_NONATOMIC)
        }
    }
    
    @discardableResult
    private func jh_constrain(attribute: NSLayoutConstraint.Attribute,
                              toSuperView: UIView?,
                              constant: CGFloat,
                              relation: NSLayoutConstraint.Relation) -> NSLayoutConstraint {
        var offset = constant
        var new_relation = relation
        if attribute == .bottom || attribute == .right || attribute == .trailing {
            offset = -constant
            if relation == .lessThanOrEqual {
                new_relation = .greaterThanOrEqual
            } else if relation == .greaterThanOrEqual {
                new_relation = .lessThanOrEqual
            }
        }
        return jh_constrain(attribute: attribute,
                            toAttribute: attribute,
                            otherView: toSuperView,
                            multiplier: 1.0,
                            constant: offset,
                            relation: new_relation)
    }
    
    @discardableResult
    private func jh_constrain(attribute: NSLayoutConstraint.Attribute,
                              toAttribute: NSLayoutConstraint.Attribute,
                              otherView: UIView?,
                              multiplier: CGFloat,
                              constant: CGFloat,
                              relation: NSLayoutConstraint.Relation) -> NSLayoutConstraint {
        self.translatesAutoresizingMaskIntoConstraints = false
        
        let layoutKey = "\(attribute.rawValue)-\(relation.rawValue)-\((otherView?.hash ?? 0))-\(toAttribute.rawValue)-\(multiplier)"
        // 判断是否存在相同约束
        guard let constraint = self.jh_layoutConstraints[layoutKey] else {
            // 不存在就新建
            let constraint = NSLayoutConstraint(item: self, attribute: attribute, relatedBy: relation, toItem: otherView, attribute: toAttribute, multiplier: multiplier, constant: constant)
            self.jh_layoutConstraints[layoutKey] = constraint
            self.jh_lastConstraint = constraint
            constraint.isActive = true
            return constraint
        }
        // 存在就更新
        constraint.constant = constant
        self.jh_lastConstraint = constraint
        constraint.isActive = true
        return constraint
    }
    
}

// MARK: - Public
extension UIView {
    @discardableResult
    public func jh_constrainAttribute(_ attribute: NSLayoutConstraint.Attribute,
                                      toAttribute: NSLayoutConstraint.Attribute,
                                      of otherView: UIView) -> NSLayoutConstraint {
        jh_constrainAttribute(attribute,
                              toAttribute: toAttribute,
                              of: otherView,
                              offset: 1.0)
    }
    
    @discardableResult
    public func jh_constrainAttribute(_ attribute: NSLayoutConstraint.Attribute,
                                      toAttribute: NSLayoutConstraint.Attribute,
                                      of otherView: UIView,
                                      offset: CGFloat) -> NSLayoutConstraint {
        jh_constrainAttribute(attribute,
                              toAttribute: toAttribute,
                              of: otherView,
                              offset: offset,
                              relation: .equal)
    }
    
    @discardableResult
    public func jh_constrainAttribute(_ attribute: NSLayoutConstraint.Attribute,
                                      toAttribute: NSLayoutConstraint.Attribute,
                                      of otherView: UIView?,
                                      offset: CGFloat,
                                      relation: NSLayoutConstraint.Relation) -> NSLayoutConstraint {
        jh_constrain(attribute: attribute,
                     toAttribute: toAttribute,
                     otherView: otherView,
                     multiplier: 1.0,
                     constant: offset,
                     relation: relation)
    }
    
    @discardableResult
    public func jh_constrainAttribute(_ attribute: NSLayoutConstraint.Attribute,
                                       toAttribute: NSLayoutConstraint.Attribute,
                                       of otherView: UIView,
                                       multiplier: CGFloat) -> NSLayoutConstraint {
        jh_constrainAttribute(attribute,
                               toAttribute: toAttribute,
                               of: otherView,
                               multiplier: multiplier,
                               relation: .equal)
    }
    
    @discardableResult
    public func jh_constrainAttribute(_ attribute: NSLayoutConstraint.Attribute,
                                       toAttribute: NSLayoutConstraint.Attribute,
                                       of otherView: UIView,
                                       multiplier: CGFloat,
                                       relation: NSLayoutConstraint.Relation) -> NSLayoutConstraint {
        jh_constrain(attribute: attribute,
                     toAttribute: toAttribute,
                     otherView: otherView,
                     multiplier: multiplier,
                     constant: 0.0,
                     relation: relation)
    }
    
    @discardableResult
    public func jh_constraint(_ attribute: NSLayoutConstraint.Attribute,
                              toAttribute: NSLayoutConstraint.Attribute,
                              otherView: UIView?,
                              offset: CGFloat,
                              multiplier: CGFloat,
                              relation: NSLayoutConstraint.Relation) -> NSLayoutConstraint {
        jh_constrain(attribute: attribute, toAttribute: toAttribute, otherView: otherView, multiplier: multiplier, constant: offset, relation: relation)
    }
    
}

// MARK: - Constraint
extension UIView {
    
    /// 最新一条约束
    public var jh_lastConstraint: NSLayoutConstraint? {
        set {
            objc_setAssociatedObject(self, &Key.lastConstraint, newValue, .OBJC_ASSOCIATION_RETAIN_NONATOMIC)
        }
        
        get {
            objc_getAssociatedObject(self, &Key.lastConstraint) as? NSLayoutConstraint
        }
    }
    
    
    
    public func jh_constraint(_ attribute: NSLayoutConstraint.Attribute,
                              toAttribute: NSLayoutConstraint.Attribute,
                              otherView: UIView?,
                              multiplier: CGFloat = 1.0,
                              relation: NSLayoutConstraint.Relation) -> NSLayoutConstraint? {
        let layoutKey = "\(attribute.rawValue)-\(relation.rawValue)-\((otherView?.hash ?? 0))-\(toAttribute.rawValue)-\(multiplier)"
        return jh_layoutConstraints[layoutKey]
    }
}

// MARK: - All
extension UIView {
    /// 移除所有约束
    public func jh_removeAllConstraints() {
        NSLayoutConstraint.deactivate(jh_allConstraints)
        jh_layoutConstraints.removeAll()
        translatesAutoresizingMaskIntoConstraints = true
        jh_lastConstraint = nil
    }
}

// MARK: - Compression
extension UIView {
    /// 抗水平方向压缩
    public var jh_compressionHorizontal: UILayoutPriority {
        get {
            contentCompressionResistancePriority(for: .horizontal)
        }
        
        set {
            setContentCompressionResistancePriority(newValue, for: .horizontal)
        }
    }
    
    /// 抗垂直方向压缩
    public var jh_compressionVertical: UILayoutPriority {
        get {
            contentCompressionResistancePriority(for: .vertical)
        }
        
        set {
            setContentCompressionResistancePriority(newValue, for: .vertical)
        }
    }
    
    /// 抗水平方向拉伸
    public var jh_huggingHorizontal: UILayoutPriority {
        get {
            contentHuggingPriority(for: .horizontal)
        }
        
        set {
            setContentHuggingPriority(newValue, for: .horizontal)
        }
    }
    
    /// 抗垂直方向拉伸
    public var jh_huggingVertical: UILayoutPriority {
        get {
            contentHuggingPriority(for: .vertical)
        }
        
        set {
            setContentHuggingPriority(newValue, for: .vertical)
        }
    }
}

// MARK: - Collapse
extension UIView {
    /// 设置视图是否伸缩，默认false，true时常量值为0，false时常量值为原始值
    public var jh_collapsed: Bool {
        set {
            jh_allConstraints.forEach {
                if newValue {
                    $0.constant = 0
                } else {
                    $0.constant = $0.jh_originalConstraint
                }
            }
            objc_setAssociatedObject(self, &Key.collapsed, newValue, .OBJC_ASSOCIATION_ASSIGN)
        }
        get {
            objc_getAssociatedObject(self, &Key.collapsed) as? Bool ?? false
        }
    }
    /// 设置视图是否自动收缩，如image为nil，text为nil、@""时自动收缩，默认false
    public var jh_autoCollapse: Bool {
        set {
            objc_setAssociatedObject(self, &Key.autoCollapse, newValue, .OBJC_ASSOCIATION_ASSIGN)
        }
        
        get {
            objc_getAssociatedObject(self, &Key.autoCollapse) as? Bool ?? false
        }
    }
    /// 设置视图是否隐藏时自动收缩、显示时自动展开，默认false
    public var jh_hiddenCollapse: Bool {
        set {
            objc_setAssociatedObject(self, &Key.hiddenCollapse, newValue, .OBJC_ASSOCIATION_ASSIGN)
        }
        
        get {
            objc_getAssociatedObject(self, &Key.hiddenCollapse) as? Bool ?? false
        }
    }
}

// MARK: - Axis
extension UIView {
    @discardableResult
    public func jh_alignCenterToSuperView(with offset: CGPoint = .zero) -> [NSLayoutConstraint] {
        var constrints = [NSLayoutConstraint]()
        constrints.append(jh_alignAxisToSuperView(.centerX, withOffset: offset.x))
        constrints.append(jh_alignAxisToSuperView(.centerY, withOffset: offset.y))
        return constrints
    }
    
    @discardableResult
    public func jh_alignAxisToSuperView(_ axis: NSLayoutConstraint.Attribute,
                                        withOffset: CGFloat = 0) -> NSLayoutConstraint {
        jh_constrain(attribute: axis, toSuperView: self.superview, constant: withOffset, relation: .equal)
    }
    
    @discardableResult
    public func jh_alignAxis(_ axis: NSLayoutConstraint.Attribute,
                             to otherView: UIView,
                             offset: CGFloat = 0,
                             multiplier: CGFloat = 1.0) -> NSLayoutConstraint {
        jh_constrain(attribute: axis, toAttribute: axis, otherView: otherView, multiplier: multiplier, constant: offset, relation: .equal)
    }
}

// MARK: - Edge
extension UIView {
    @discardableResult
    public func jh_pinEdgesToSuperView() -> [NSLayoutConstraint] {
        jh_pinEdgesToSuperView(.zero)
    }
    
    @discardableResult
    public func jh_pinEdgesToSuperView(_ insets: UIEdgeInsets) -> [NSLayoutConstraint] {
        var constraints = [NSLayoutConstraint]()
        constraints.append(jh_pinEdgeToSuperView(.top, inset: insets.top))
        constraints.append(jh_pinEdgeToSuperView(.bottom, inset: insets.bottom))
        constraints.append(jh_pinEdgeToSuperView(.leading, inset: insets.left))
        constraints.append(jh_pinEdgeToSuperView(.trailing, inset: insets.right))
        return constraints
    }
    
    @discardableResult
    public func jh_pinEdgesToSuperView(_ insets: UIEdgeInsets,
                                       excludingEdge: NSLayoutConstraint.Attribute) -> [NSLayoutConstraint] {
        var constraints = [NSLayoutConstraint]()
        if excludingEdge != .top {
            constraints.append(jh_pinEdgeToSuperView(.top, inset: insets.top))
        }
        if excludingEdge != .bottom {
            constraints.append(jh_pinEdgeToSuperView(.bottom, inset: insets.bottom))
        }
        if excludingEdge != .leading && excludingEdge != .left {
            constraints.append(jh_pinEdgeToSuperView(.leading, inset: insets.left))
        }
        if excludingEdge != .trailing && excludingEdge != .right {
            constraints.append(jh_pinEdgeToSuperView(.trailing, inset: insets.right))
        }
        return constraints
    }
    
    @discardableResult
    public func jh_pinEdgesToSuperViewHorizontal(inset: CGFloat = 0) -> [NSLayoutConstraint] {
        var constraints = [NSLayoutConstraint]()
        constraints.append(jh_pinEdgeToSuperView(.leading, inset: inset))
        constraints.append(jh_pinEdgeToSuperView(.trailing, inset: inset))
        return constraints
    }
    
    @discardableResult
    public func jh_pinEdgesToSuperViewVertical(inset: CGFloat = 0) -> [NSLayoutConstraint] {
        var constraints = [NSLayoutConstraint]()
        constraints.append(jh_pinEdgeToSuperView(.top, inset: inset))
        constraints.append(jh_pinEdgeToSuperView(.bottom, inset: inset))
        return constraints
    }
    
    @discardableResult
    public func jh_pinEdgeToSuperView(_ edge: NSLayoutConstraint.Attribute) -> NSLayoutConstraint {
        jh_pinEdgeToSuperView(edge,
                              inset: 0.0)
    }
    
    @discardableResult
    public func jh_pinEdgeToSuperView(_ edge: NSLayoutConstraint.Attribute, inset: CGFloat) -> NSLayoutConstraint {
        jh_pinEdgeToSuperView(edge,
                              inset: inset,
                              relation: .equal)
    }
    
    @discardableResult
    public func jh_pinEdgeToSuperView(_ edge: NSLayoutConstraint.Attribute,
                           inset: CGFloat,
                           relation: NSLayoutConstraint.Relation) -> NSLayoutConstraint {
        jh_constrain(attribute: edge,
                     toSuperView: self.superview,
                     constant: inset,
                     relation: relation)
    }
    
    @discardableResult
    public func jh_pinEdge(_ edge: NSLayoutConstraint.Attribute,
                           toEdge: NSLayoutConstraint.Attribute,
                           of otherView: UIView) -> NSLayoutConstraint {
        jh_pinEdge(edge,
                   toEdge: toEdge,
                   of: otherView,
                   offset: 0.0)
    }
    
    @discardableResult
    public func jh_pinEdge(_ edge: NSLayoutConstraint.Attribute,
                           toEdge: NSLayoutConstraint.Attribute,
                           of otherView: UIView,
                           offset: CGFloat) -> NSLayoutConstraint {
        jh_pinEdge(edge,
                   toEdge: toEdge,
                   of: otherView,
                   offset: offset,
                   relation: .equal)
    }
    
    @discardableResult
    public func jh_pinEdge(_ edge: NSLayoutConstraint.Attribute,
                           toEdge: NSLayoutConstraint.Attribute,
                           of otherView: UIView,
                           offset: CGFloat,
                           relation: NSLayoutConstraint.Relation) -> NSLayoutConstraint {
        jh_constrainAttribute(edge,
                              toAttribute: toEdge,
                              of: otherView,
                              offset: offset,
                              relation: relation)
    }
}

// MARK: - Dimension
extension UIView {
    @discardableResult
    public func jh_setDimensionToSize(_ size: CGSize) -> [NSLayoutConstraint] {
        var constraints = [NSLayoutConstraint]()
        constraints.append(jh_setDimension(.width, toSize: size.width))
        constraints.append(jh_setDimension(.height, toSize: size.height))
        return constraints
    }
    
    @discardableResult
    public func jh_setDimension(_ dimension: NSLayoutConstraint.Attribute,
                                toSize: CGFloat = 0,
                                relation: NSLayoutConstraint.Relation = .equal) -> NSLayoutConstraint {
        jh_constrain(attribute: dimension, toAttribute: .notAnAttribute, otherView: nil, multiplier: 1.0, constant: toSize, relation: relation)
    }
    
    @discardableResult
    public func jh_matchDimension(_ dimension: NSLayoutConstraint.Attribute,
                                  toDimension: NSLayoutConstraint.Attribute,
                                  ofView otherView: UIView,
                                  offset: CGFloat = 0,
                                  relation: NSLayoutConstraint.Relation = .equal) -> NSLayoutConstraint {
        jh_constrainAttribute(dimension, toAttribute: toDimension, of: otherView, offset: offset, relation: relation)
    }
    
    @discardableResult
    public func jh_matchDimension(_ dimension: NSLayoutConstraint.Attribute,
                                  toDimension: NSLayoutConstraint.Attribute,
                                  multiplier: CGFloat = 1.0,
                                  relation: NSLayoutConstraint.Relation = .equal) -> NSLayoutConstraint {
        jh_constrainAttribute(dimension, toAttribute: toDimension, of: self, multiplier: multiplier, relation: relation)
    }
    
    @discardableResult
    public func jh_matchDimension(_ dimension: NSLayoutConstraint.Attribute,
                                  toDimension: NSLayoutConstraint.Attribute,
                                  ofView otherView: UIView,
                                  multiplier: CGFloat,
                                  relation: NSLayoutConstraint.Relation) -> NSLayoutConstraint {
        jh_constrainAttribute(dimension, toAttribute: toDimension, of: otherView, multiplier: multiplier, relation: relation)
    }
    
    @discardableResult
    public func jh_matchDimension(_ dimension: NSLayoutConstraint.Attribute,
                                  toDimension: NSLayoutConstraint.Attribute,
                                  ofView otherView: UIView,
                                  offset: CGFloat,
                                  multiplier: CGFloat,
                                  relation: NSLayoutConstraint.Relation) -> NSLayoutConstraint {
        jh_constrain(attribute: dimension, toAttribute: toDimension, otherView: otherView, multiplier: multiplier, constant: offset, relation: relation)
    }
    
}

// MARK: - LayoutChain
extension UIView {
    
   public var layoutChain: AutoLayoutSwift {
        get {
            guard let layout = objc_getAssociatedObject(self, &Key.jhLayoutChain) as? AutoLayoutSwift else {
                let layout = AutoLayoutSwift(view: self)
                objc_setAssociatedObject(self, &Key.jhLayoutChain, layout, .OBJC_ASSOCIATION_RETAIN_NONATOMIC)
                return layout
            }
            return layout
        }
    }
}