import UIKit
import Runestone

final class PadXcodeTheme: Theme {
    var backgroundColor:                     UIColor { UIColor(hex: "#1E1E1E") }
    var userInterfaceStyle:                  UIUserInterfaceStyle { .dark }
    var font:                                UIFont  { UIFont.monospacedSystemFont(ofSize: 14, weight: .regular) }
    var textColor:                           UIColor { UIColor(hex: "#D4D4D4") }
    var gutterBackgroundColor:               UIColor { UIColor(hex: "#252526") }
    var gutterHairlineColor:                 UIColor { UIColor(hex: "#3C3C3C") }
    var lineNumberColor:                     UIColor { UIColor(hex: "#6E7681") }
    var lineNumberFont:                      UIFont  { UIFont.monospacedSystemFont(ofSize: 12, weight: .regular) }
    var selectedLineBackgroundColor:         UIColor { UIColor(hex: "#2A2D2E") }
    var selectedLinesLineNumberColor:        UIColor { UIColor(hex: "#C8C8C8") }
    var selectedLinesGutterBackgroundColor:  UIColor { UIColor(hex: "#2A2D2E") }
    var markedTextBackgroundColor:           UIColor { UIColor(hex: "#264F78").withAlphaComponent(0.4) }
    var markedTextBackgroundCornerRadius:    CGFloat { 2 }
    var invisibleCharactersColor:            UIColor { UIColor(hex: "#404040") }
    var pageGuideHairlineColor:              UIColor { UIColor(hex: "#404040") }
    var pageGuideBackgroundColor:            UIColor { UIColor(hex: "#1A1A1A") }

    func textStyle(for highlightName: String) -> TextStyle? {
        switch highlightName {
        case "keyword", "keyword.control", "keyword.operator", "keyword.other",
             "keyword.declaration", "storage.type":
            return TextStyle(color: UIColor(hex: "#FF7AB2"), bold: true)
        case "storage.modifier":
            return TextStyle(color: UIColor(hex: "#FF7AB2"))
        case "type", "type.builtin", "entity.name.type", "entity.name.type.class",
             "entity.name.type.struct", "entity.name.type.enum", "entity.name.type.protocol":
            return TextStyle(color: UIColor(hex: "#DABAFF"))
        case "type.parameter":
            return TextStyle(color: UIColor(hex: "#6BDFFF"))
        case "function", "entity.name.function", "meta.function-call", "function.method":
            return TextStyle(color: UIColor(hex: "#67B7FB"))
        case "function.builtin":
            return TextStyle(color: UIColor(hex: "#67B7FB"), bold: true)
        case "variable", "variable.other", "variable.other.member":
            return TextStyle(color: UIColor(hex: "#D4D4D4"))
        case "variable.builtin":
            return TextStyle(color: UIColor(hex: "#FF7AB2"))
        case "property", "variable.other.property":
            return TextStyle(color: UIColor(hex: "#72B9D5"))
        case "constant", "constant.builtin":
            return TextStyle(color: UIColor(hex: "#D9C97C"), bold: true)
        case "constant.numeric", "number":
            return TextStyle(color: UIColor(hex: "#D9C97C"))
        case "string", "string.special":
            return TextStyle(color: UIColor(hex: "#FF8170"))
        case "string.escape":
            return TextStyle(color: UIColor(hex: "#FF8170"), bold: true)
        case "comment", "comment.line", "comment.block":
            return TextStyle(color: UIColor(hex: "#7F8C98"), italic: true)
        case "comment.block.documentation":
            return TextStyle(color: UIColor(hex: "#6A9955"), italic: true)
        case "operator", "punctuation.operator", "punctuation.bracket", "punctuation.delimiter":
            return TextStyle(color: UIColor(hex: "#D4D4D4"))
        case "attribute":
            return TextStyle(color: UIColor(hex: "#BF86C8"))
        default:
            return nil
        }
    }
}

final class PadXcodeLightTheme: Theme {
    var backgroundColor:                     UIColor { UIColor(hex: "#FFFFFF") }
    var userInterfaceStyle:                  UIUserInterfaceStyle { .light }
    var font:                                UIFont  { UIFont.monospacedSystemFont(ofSize: 14, weight: .regular) }
    var textColor:                           UIColor { UIColor(hex: "#000000") }
    var gutterBackgroundColor:               UIColor { UIColor(hex: "#F2F2F2") }
    var gutterHairlineColor:                 UIColor { UIColor(hex: "#D8D8D8") }
    var lineNumberColor:                     UIColor { UIColor(hex: "#A0A0A0") }
    var lineNumberFont:                      UIFont  { UIFont.monospacedSystemFont(ofSize: 12, weight: .regular) }
    var selectedLineBackgroundColor:         UIColor { UIColor(hex: "#ECF5FF") }
    var selectedLinesLineNumberColor:        UIColor { UIColor(hex: "#3A3A3A") }
    var selectedLinesGutterBackgroundColor:  UIColor { UIColor(hex: "#E8F0FA") }
    var markedTextBackgroundColor:           UIColor { UIColor(hex: "#B5D0F7").withAlphaComponent(0.4) }
    var markedTextBackgroundCornerRadius:    CGFloat { 2 }
    var invisibleCharactersColor:            UIColor { UIColor(hex: "#CCCCCC") }
    var pageGuideHairlineColor:              UIColor { UIColor(hex: "#DDDDDD") }
    var pageGuideBackgroundColor:            UIColor { UIColor(hex: "#F9F9F9") }

    func textStyle(for highlightName: String) -> TextStyle? {
        switch highlightName {
        case "keyword", "keyword.control", "keyword.operator", "keyword.other",
             "keyword.declaration", "storage.type":
            return TextStyle(color: UIColor(hex: "#AD3DA4"), bold: true)
        case "storage.modifier":
            return TextStyle(color: UIColor(hex: "#AD3DA4"))
        case "type", "type.builtin", "entity.name.type", "entity.name.type.class",
             "entity.name.type.struct", "entity.name.type.enum", "entity.name.type.protocol":
            return TextStyle(color: UIColor(hex: "#703DAA"))
        case "type.parameter":
            return TextStyle(color: UIColor(hex: "#047CB0"))
        case "function", "entity.name.function", "meta.function-call", "function.method":
            return TextStyle(color: UIColor(hex: "#3900A0"))
        case "function.builtin":
            return TextStyle(color: UIColor(hex: "#3900A0"), bold: true)
        case "variable", "variable.other", "variable.other.member":
            return TextStyle(color: UIColor(hex: "#000000"))
        case "variable.builtin":
            return TextStyle(color: UIColor(hex: "#AD3DA4"))
        case "property", "variable.other.property":
            return TextStyle(color: UIColor(hex: "#047CB0"))
        case "constant", "constant.builtin":
            return TextStyle(color: UIColor(hex: "#272AD8"), bold: true)
        case "constant.numeric", "number":
            return TextStyle(color: UIColor(hex: "#272AD8"))
        case "string", "string.special":
            return TextStyle(color: UIColor(hex: "#C41A16"))
        case "string.escape":
            return TextStyle(color: UIColor(hex: "#C41A16"), bold: true)
        case "comment", "comment.line", "comment.block":
            return TextStyle(color: UIColor(hex: "#5D6C79"), italic: true)
        case "comment.block.documentation":
            return TextStyle(color: UIColor(hex: "#265B31"), italic: true)
        case "operator", "punctuation.operator", "punctuation.bracket", "punctuation.delimiter":
            return TextStyle(color: UIColor(hex: "#000000"))
        case "attribute":
            return TextStyle(color: UIColor(hex: "#6C36A9"))
        default:
            return nil
        }
    }
}

// MARK: - TextStyle helpers

extension TextStyle {
    init(color: UIColor, bold: Bool = false, italic: Bool = false) {
        self.init()
        self.color = color
        if bold   { self.fontTraits.insert(.traitBold) }
        if italic { self.fontTraits.insert(.traitItalic) }
    }
}

// MARK: - UIColor hex

extension UIColor {
    convenience init(hex: String) {
        var h = hex.trimmingCharacters(in: .whitespacesAndNewlines)
        h = h.hasPrefix("#") ? String(h.dropFirst()) : h
        var rgb: UInt64 = 0
        Scanner(string: h).scanHexInt64(&rgb)
        self.init(red:   CGFloat((rgb >> 16) & 0xFF) / 255,
                  green: CGFloat((rgb >>  8) & 0xFF) / 255,
                  blue:  CGFloat( rgb        & 0xFF) / 255, alpha: 1)
    }
}