//
//  DevikTextField.swift
//  GMETextFIeld
//
//  Created by InKwon Devik Kim on 16/04/2019.
//  Copyright © 2019 devikkim. All rights reserved.
//

import UIKit
import RxSwift

@IBDesignable open class ValidationTextField: UITextField {
  @objc public enum ValidateTextFieldType: Int {
    case dropdown
    case `default`
  }
  
  // MARK: Left Flag View
  private var leftViewPadding: CGFloat = 8
  private var widthOfImageInLeftView: CGFloat = 35
  private var leftFlagImageWidth: CGFloat = 0
  // MARK: Heights
  
  private var lineHeight: CGFloat = 0
  private var selectedLineHeight: CGFloat = 0
  
  // MARK: IBInspectable
  @IBInspectable open var isShowTitle: Bool = true {
    didSet {
      update()
    }
  }
  
  @IBInspectable open var isUseTitle: Bool = true {
    didSet {
      update()
    }
  }
  
  @IBInspectable open var isLineHidden: Bool = false {
    didSet {
      update()
    }
  }
  
  @IBInspectable open var titleText: String = "TITLE" {
    didSet {
      update()
    }
  }
  
  @IBInspectable open var titleFont: UIFont = .sanfrancisco(.regular, size: 12) {
    didSet {
      update()
      createTitleLabel()
    }
  }
    @IBInspectable open var titleColor: UIColor = .themeTitleTextColor {
    didSet {
      update()
    }
  }
  
  @IBInspectable open var errorColor: UIColor = .themeRed {
    didSet {
      update()
    }
  }
  
  @IBInspectable open var errorFont: UIFont = .sanfrancisco(.regular, size: 12) {
    didSet {
      update()
      createTitleLabel()
    }
  }
  
  @IBInspectable open var errorMessage: String? {
    didSet {
      update()
    }
  }
  
  @IBInspectable open var disabledColor: UIColor = UIColor(white: 0.88, alpha: 1.0) {
    didSet {
      update()
      updatePlaceholder()
    }
  }
  
  @IBInspectable open override var placeholder: String? {
    didSet {
      setNeedsDisplay()
      update()
    }
  }
  
  @IBInspectable open var placeholderColor: UIColor = UIColor(red:0.49, green:0.49, blue:0.49, alpha:1.0) {
    didSet {
      updatePlaceholder()
    }
  }
  
  @IBInspectable open var leftImage: UIImage? {
    didSet {
      let width = textHeight() * 1.5
      let height = textHeight()
      
      leftImageView = UIImageView(frame:
        CGRect(x: 0, y: 0, width: width, height: height)
      )
      
      let view = UIView()
      view.addSubview(leftImageView)
      
      leftImageView.image = leftImage
      leftImageView.translatesAutoresizingMaskIntoConstraints = false
      leftImageView.centerYAnchor.constraint(equalTo: view.centerYAnchor).isActive = true
      leftImageView.centerXAnchor.constraint(equalTo: view.centerXAnchor).isActive = true
      leftImageView.widthAnchor.constraint(equalToConstant: width).isActive = true
      leftImageView.heightAnchor.constraint(equalToConstant: height).isActive = true
      
      leftImageView.contentMode = .scaleAspectFit
      
      leftContainerView = view
      
      leftView = leftContainerView
      leftViewMode = .always
      
      leftFlagImageWidth = width
    }
  }
  
  @IBInspectable open var leftImageTintColor: UIColor? {
    didSet {
      guard let color = leftImageTintColor else {
        return
      }
      leftImageView.image  = leftImage?.withRenderingMode(UIImage.RenderingMode.alwaysTemplate)
      leftImageView.tintColor = color
    }
  }
  
  // MARK: Properties
  
  open var validCondition: ((String) -> Bool)? {
    didSet {
      editingChanged()
    }
  }
  
  open var mobileNumberText: String? {
    set {
      text = newValue?.replacingOccurrences(of: countryCode?.phoneCode ?? "", with: "")
    }
    get {
      return "\(countryCode?.phoneCode ?? "")\(text ?? "")"
    }
  }
  
  private var countryCode: CountryEnum? {
    didSet {
      mobileNumberText = text
    }
  }
  
  open var isValid = false
  
  open var valid = BehaviorSubject<Bool>(value: false)
  
  private lazy var leftImageView = UIImageView()
  
  private var leftContainerView: UIView?
  
  private lazy var titleLabel = UILabel()
  
  private lazy var errorLabel = UILabel()
  
  private lazy var lineView = UIView()
  
  private var bankCode: BankEnum?
  
  private var titleFadeInDuration: TimeInterval = 0.3
  
  private var titleFadeOutDuration: TimeInterval = 0.5
  
  private var placeholderFont: UIFont? {
    didSet {
      updatePlaceholder()
    }
  }
  
  private var isTitleVisible: Bool {
    return hasText
  }
  
  private var editingOrSelected: Bool {
    return super.isEditing || isSelected
  }
  
  // MARK: DropDown
  private var type: ValidateTextFieldType = .default {
    didSet {
      switch type {
      case .default:
        inputView = nil
        tintColor = .themeText
      case .dropdown:
        inputView = UIView()
        tintColor = .clear
        
        let dropdownImage = UIImageView()
        dropdownImage.setDropDownImage(tintColor: .themeTextColor)
        rightView = dropdownImage
        rightViewMode = .always
        
      }
    }
  }
  
  private lazy var tablePresenterWireframe = TablePresenterWireframe()
  
  private var dropwDownItems: [TablePresenterProtocol]?
  
  private var configure: TablePresenterConfiguration?
  
  var selectedItem = BehaviorSubject<TablePresenterProtocol?>(value: nil)
  // MARK: Initialize
  
  override init(frame: CGRect) {
    super.init(frame: frame)
    initValidationTextField()
  }
  
  required public init?(coder aDecoder: NSCoder) {
    super.init(coder: aDecoder)
    initValidationTextField()
  }
  
  private func initValidationTextField() {
    borderStyle = .none
    createTitleLabel()
    createLineView()
    createErrorLabel()
    
    addTarget(self, action: #selector(editingDidBegin), for: .editingDidBegin)
    addTarget(self, action: #selector(editingChanged), for: [.editingChanged, .valueChanged])
  }
  
  @objc private func editingDidBegin() {
    switch type {
    case .dropdown:
      guard let parentVC = parentContainerViewController() else {
        return
      }
      
      if dropwDownItems != nil {
        keyboardToolbar.isHidden = true
        
        tablePresenterWireframe.openWith(
          delegate: self,
          model: dropwDownItems,
          source: parentVC
        )
      }
      
    default: ()
    }
  }
  
  @objc private func editingChanged() {
    if let isValid = validCondition?(self.text ?? ""), !isValid {
      self.isValid = isValid
      valid.onNext(isValid)
    } else {
      isValid = true
      valid.onNext(isValid)
    }
    
    update()
    
    updateTitleVisibility(true)
  }
  
  private func createTitleLabel() {
    titleLabel = UILabel()
    
    titleLabel.autoresizingMask = [.flexibleWidth,. flexibleHeight]
    titleLabel.font = titleFont
    titleLabel.textColor = titleColor
    
    addSubview(titleLabel)
  }
  
  private func createLineView() {
    lineView.isUserInteractionEnabled = false
    lineView.backgroundColor = titleColor
    configureDefaultLineHeight()

    lineView.autoresizingMask = [.flexibleWidth, .flexibleTopMargin]
    addSubview(lineView)
  }
  
  private func createErrorLabel() {
    errorLabel.minimumScaleFactor = 0.5
    errorLabel.adjustsFontSizeToFitWidth = true
    
    errorLabel.autoresizingMask = [.flexibleWidth, .flexibleTopMargin]
    addSubview(errorLabel)
  }
  
  private func titleHeight() -> CGFloat {
    return titleLabel.font.lineHeight
  }
  
  private func errorHeight() -> CGFloat {
    return errorLabel.font.lineHeight
  }
  
  private func configureDefaultLineHeight() {
    let pixel: CGFloat = 1.0 / UIScreen.main.scale
    lineHeight = 2.0 * pixel
    selectedLineHeight = 2.0 * lineHeight
  }
  
  private func titleRectForBounds(_ bounds: CGRect, editing: Bool) -> CGRect {
    if isShowTitle {
      return CGRect(
        x: 0,
        y: 0,
        width: bounds.size.width,
        height: titleHeight()
      )
    } else {
      if editing {
        return CGRect(
          x: 0,
          y: 0,
          width: bounds.size.width,
          height: titleHeight()
        )
      } else {
        return CGRect(
          x: 0,
          y: titleHeight(),
          width: bounds.size.width,
          height: titleHeight()
        )
      }
    }
  }
  
  private func lineViewRectForBounds(_ bounds: CGRect, editing: Bool) -> CGRect {
    let height = editing ? selectedLineHeight : lineHeight
    
    return CGRect(
      x: 0,
      y: bounds.size.height - height,
      width: bounds.size.width,
      height: height
    )
  }
  
  private func errorLabelRectForBounds(_ bounds: CGRect) -> CGRect {
    if isValid {
      return CGRect(
        x: 0,
        y: bounds.height + errorHeight(),
        width: 0,
        height: 0
      )
    } else {
      return CGRect(
        x: 0,
        y: bounds.height,
        width: bounds.size.width,
        height: errorHeight()
      )
    }
  }
  
  private func textHeight() -> CGFloat {
    guard let font = self.font else { return 0.0 }
    
    return font.lineHeight + 3.0
  }
  
  private func updateTitleVisibility(_ animated: Bool = false) {
    let alpha: CGFloat
    
    if isShowTitle {
      alpha = 1.0
    } else {
      alpha = isTitleVisible ? 1.0 : 0.0
    }
    
    let frame = titleRectForBounds(bounds, editing: isTitleVisible)
    
    let errorAlpha: CGFloat = isValid || text == "" ? 0.0 : 1.0
    let errorLabelFrame = errorLabelRectForBounds(bounds)
    
    let updateBlock = {() -> Void in
      if !self.isShowTitle {
        self.titleLabel.alpha = alpha
        self.titleLabel.frame = frame
      }
      
      self.errorLabel.alpha = errorAlpha
      self.errorLabel.frame = errorLabelFrame
    }
    
    if animated {
      #if swift(>=4.2)
      let animationOptions: UIView.AnimationOptions = .curveEaseOut
      #else
      let animationOptions: UIViewAnimationOptions = .curveEaseOut
      #endif
      
      let duration = isTitleVisible ? titleFadeInDuration : titleFadeOutDuration
      
      UIView.animate(
        withDuration: duration,
        delay: 0,
        options: animationOptions,
        animations: { () -> Void in
          updateBlock()
        },
        completion: nil)
    }
  }
  
  private func update() {
    lineView.isHidden = isLineHidden
    
    if !isValid && text != "" {
      errorLabel.text = errorMessage
      errorLabel.textColor = errorColor
      errorLabel.font = errorFont
      lineView.backgroundColor = errorColor
    } else {
      lineView.backgroundColor = titleColor
    }
    
    if isUseTitle {
      titleLabel.isHidden = false
      titleLabel.alpha = 1.0
    } else {
      titleLabel.isHidden = true
      titleLabel.alpha = 0.0
    }
    
    titleLabel.text = titleText
    titleLabel.textColor = titleColor
    titleLabel.font = titleFont
    
    updateTitleVisibility(true)
    
    if !isEnabled {
      lineView.backgroundColor = disabledColor
    }
  }
  
  private func updatePlaceholder() {
    guard let placeholder = placeholder, let font = placeholderFont ?? font else {
      return
    }
    let color = isEnabled ? placeholderColor : disabledColor
    #if swift(>=4.2)
    attributedPlaceholder = NSAttributedString(
      string: placeholder,
      attributes: [
        NSAttributedString.Key.foregroundColor: color, NSAttributedString.Key.font: font
      ]
    )
    #elseif swift(>=4.0)
    attributedPlaceholder = NSAttributedString(
      string: placeholder,
      attributes: [
        NSAttributedStringKey.foregroundColor: color, NSAttributedStringKey.font: font
      ]
    )
    #else
    attributedPlaceholder = NSAttributedString(
      string: placeholder,
      attributes: [NSForegroundColorAttributeName: color, NSFontAttributeName: font]
    )
    #endif
  }
  
  override open func textRect(forBounds bounds: CGRect) -> CGRect {
    let superRect = super.textRect(forBounds: bounds)
    let titleHeight = self.titleHeight()
    
    let padding: CGFloat = leftImage == nil ? 0 : 10
    
    return CGRect(
      x: superRect.origin.x + padding,
      y: titleHeight,
      width: superRect.size.width - padding,
      height: superRect.size.height - titleHeight - selectedLineHeight
    )
  }
  
  override open func editingRect(forBounds bounds: CGRect) -> CGRect {
    let superRect = super.editingRect(forBounds: bounds)
    let titleHeight = self.titleHeight()
    
    let padding: CGFloat = leftImage == nil ? 0 : 10
    
    return CGRect(
      x: superRect.origin.x + padding,
      y: titleHeight,
      width: superRect.size.width,
      height: superRect.size.height - titleHeight - selectedLineHeight
    )
  }
  
  override open func placeholderRect(forBounds bounds: CGRect) -> CGRect {
    let superRect = super.editingRect(forBounds: bounds)
    let titleHeight = self.titleHeight()
    
    let padding: CGFloat = leftImage == nil ? 0 : 10
    
    let rect = CGRect(
      x: superRect.origin.x + padding,
      y: titleHeight,
      width: bounds.size.width - leftFlagImageWidth - padding,
      height: bounds.size.height - titleHeight - selectedLineHeight
    )
    return rect
  }
  
  override open func leftViewRect(forBounds bounds: CGRect) -> CGRect {
    let titleHeight = self.titleHeight()
    
    let rect = CGRect (
      x: 0,
      y: titleHeight,
      width: leftFlagImageWidth,
      height: bounds.size.height - titleHeight - selectedLineHeight
    )
    return rect
  }
  
  override open func rightViewRect(forBounds bounds: CGRect) -> CGRect {
    let titleHeight = self.titleHeight()
    let size = bounds.size.height - titleHeight - selectedLineHeight
    return CGRect(
      x: bounds.width - size,
      y: titleHeight,
      width: size,
      height: size
    )
  }
  
  override open func prepareForInterfaceBuilder() {
    super.prepareForInterfaceBuilder()
    
    borderStyle = .none
    
    isSelected = true
    invalidateIntrinsicContentSize()
  }
  
  override open func layoutSubviews() {
    super.layoutSubviews()
    
    self.titleLabel.frame = titleRectForBounds(
      bounds,
      editing: isTitleVisible
    )
    
    self.lineView.frame = lineViewRectForBounds(
      bounds,
      editing: editingOrSelected
    )
    
    self.errorLabel.frame = errorLabelRectForBounds(bounds)
  }
  
  override open var intrinsicContentSize: CGSize {
    return CGSize(width: bounds.size.width, height: titleHeight() + textHeight() + 10)
  }
}

extension ValidationTextField {
  func setCountry(with code: String?, isShowCode: Bool = true) {
    guard
      let code = code?.lowercased(),
      let countryCode = CountryEnum(rawValue: code) else {
        leftView = nil
        return
    }
    
    setCountry(with: countryCode, isShowCode: isShowCode)
  }
  
  func setCountry(with code: CountryEnum, isShowCode: Bool = true) {
    countryCode = code
    widthOfImageInLeftView = 35
    let textArea = textRect(forBounds: bounds)
    
    let imageView = UIImageView(
      frame: CGRect(
        x: 0,
        y: 0,
        width: widthOfImageInLeftView,
        height: textArea.height
      )
    )
    
    imageView.contentMode = .scaleAspectFit
    imageView.image = code.flag
    
    let label = UILabel()
    label.font = font ?? UIFont.systemFont(ofSize: 14)
    label.textColor = textColor ?? .black
    label.text = code.phoneCode
    
    label.frame = CGRect(
      x: widthOfImageInLeftView + leftViewPadding,
      y: 0,
      width: label.intrinsicContentSize.width,
      height: textArea.height
    )
    
    var width: CGFloat = widthOfImageInLeftView +
      leftViewPadding +
      label.intrinsicContentSize.width +
      leftViewPadding
    
    if !isShowCode {
      width = widthOfImageInLeftView + leftViewPadding
      label.isHidden = !isShowCode
    }
    
    let paddingView = UIView(
      frame: CGRect(
        x: 0,
        y: textArea.origin.y,
        width: width,
        height: textArea.height
      )
    )
    
    paddingView.addSubview(imageView)
    paddingView.addSubview(label)
    paddingView.backgroundColor = .clear
    
    leftFlagImageWidth = paddingView.frame.width
    
    leftViewMode = .always
    leftView = paddingView
  }
  
  func setBank(with code: String?) {
    guard
      let code = code?.lowercased(),
      let bankCode = BankEnum(rawValue: code) else {
        leftView = nil
        return
    }
    
    setBank(with: bankCode)
  }
  
  func setBank(with code: BankEnum) {
    leftImageView.removeFromSuperview()
    leftImage = code.ciImage
  }
}

extension ValidationTextField {
  func useAsDropDown(with configure: TablePresenterConfiguration? = nil, items: [TablePresenterProtocol]?) {
    func isEqual(target1: [TablePresenterProtocol]?, target2: [TablePresenterProtocol]?) -> Bool {
      guard let model1 = target1, let model2 = target2 else { return false}
      
      if model1.count != model2.count {
        return false
      }
      
      for i in 0..<model1.count where model1[i].cellTitle != model2[i].cellTitle {
        return false
      }
      return true
    }
    
    if !isEqual(target1: dropwDownItems, target2: items) {
      selectedItem.onNext(nil)
      text = nil
      sendActions(for: .editingChanged)
    }
    
    self.type = .dropdown
    self.dropwDownItems = items
    self.configure = configure
  }
  
  func didSelect(item: TablePresenterProtocol?) {
    selectedItem.onNext(item)
    text = item?.cellTitle
    sendActions(for: .editingChanged)
  }
}

extension ValidationTextField: TablePresenterDelegate {
  func tablePresenterView(_ viewController: TablePresenterViewController) -> TablePresenterConfiguration {
    guard let configure = self.configure else {
      return TablePresenterConfiguration(
        presenterTitle: "DropDown",
        closeButtonTitle: "cancel_text".localized(),
        notFoundTitle: "no_result_found_text".localized(),
        searchBarPlaceHolder: "Search"
      )
    }
    return configure
  }
  
  func tablePresenterView(
    _ viewController: TablePresenterViewController,
    didSelectModel model: TablePresenterProtocol?
  ) {
    didSelect(item: model)
  }
}