import Foundation
import AsyncDisplayKit
import Display

private let textFont = Font.regular(17.0)

final class FormControllerTextInputItem: FormControllerItem {
    let title: String
    let text: String
    let placeholder: String
    let textUpdated: (String) -> Void
    
    init(title: String, text: String, placeholder: String, textUpdated: @escaping (String) -> Void) {
        self.title = title
        self.text = text
        self.placeholder = placeholder
        self.textUpdated = textUpdated
    }
    
    func node() -> ASDisplayNode & FormControllerItemNode {
        return FormControllerTextInputItemNode()
    }
    
    func update(node: ASDisplayNode & FormControllerItemNode, theme: PresentationTheme, strings: PresentationStrings, width: CGFloat, previousNeighbor: FormControllerItemNeighbor, nextNeighbor: FormControllerItemNeighbor, transition: ContainedViewLayoutTransition) -> (FormControllerItemPreLayout, (FormControllerItemLayoutParams) -> CGFloat) {
        guard let node = node as? FormControllerTextInputItemNode else {
            assertionFailure()
            return (FormControllerItemPreLayout(aligningInset: 0.0), { _ in
                return 0.0
            })
        }
        return node.updateInternal(item: self, theme: theme, strings: strings, width: width, previousNeighbor: previousNeighbor, nextNeighbor: nextNeighbor, transition: transition)
    }
}

final class FormControllerTextInputItemNode: FormBlockItemNode<FormControllerTextInputItem> {
    private let titleNode: ImmediateTextNode
    private let textField: TextFieldNode
    
    private var item: FormControllerTextInputItem?
    
    init() {
        self.titleNode = ImmediateTextNode()
        self.titleNode.maximumNumberOfLines = 1
        
        self.textField = TextFieldNode()
        self.textField.textField.font = textFont
        self.textField.textField.returnKeyType = .next
        
        super.init(selectable: false, topSeparatorInset: .regular)
        
        self.addSubnode(self.titleNode)
        self.addSubnode(self.textField)
        
        self.textField.textField.addTarget(self, action: #selector(self.editingChanged), for: [.editingChanged])
    }
    
    override func update(item: FormControllerTextInputItem, theme: PresentationTheme, strings: PresentationStrings, width: CGFloat, previousNeighbor: FormControllerItemNeighbor, nextNeighbor: FormControllerItemNeighbor, transition: ContainedViewLayoutTransition) -> (FormControllerItemPreLayout, (FormControllerItemLayoutParams) -> CGFloat) {
        self.item = item
        
        let leftInset: CGFloat = 16.0
        self.titleNode.attributedText = NSAttributedString(string: item.title, font: textFont, textColor: theme.list.itemPrimaryTextColor)
        let titleSize = self.titleNode.updateLayout(CGSize(width: width - leftInset - 70.0, height: CGFloat.greatestFiniteMagnitude))
        
        let aligningInset: CGFloat
        if titleSize.width.isZero {
            aligningInset = 0.0
        } else {
            aligningInset = leftInset + titleSize.width + 17.0
        }
        
        return (FormControllerItemPreLayout(aligningInset: aligningInset), { params in
            transition.updateFrame(node: self.titleNode, frame: CGRect(origin: CGPoint(x: leftInset, y: 11.0), size: titleSize))
            
            let attributedPlaceholder = NSAttributedString(string: item.placeholder, font: textFont, textColor: theme.list.itemPlaceholderTextColor)
            if !(self.textField.textField.attributedPlaceholder?.isEqual(to: attributedPlaceholder) ?? false) {
                self.textField.textField.attributedPlaceholder = attributedPlaceholder
            }
            self.textField.textField.textColor = theme.list.itemPrimaryTextColor
            
            if self.textField.textField.text != item.text {
                self.textField.textField.text = item.text
            }
            
            transition.updateFrame(node: self.textField, frame: CGRect(origin: CGPoint(x: params.maxAligningInset, y: 3.0), size: CGSize(width: max(1.0, width - params.maxAligningInset - 8.0), height: 40.0)))
            return 44.0
        })
    }
    
    @objc private func editingChanged() {
        self.item?.textUpdated(self.textField.textField.text ?? "")
    }
}