//

// ColorCode.swift

//

// Created by 1024jp on 2021-05-08.

//

/*

The MIT License (MIT)

© 2014-2022 1024jp

Permission is hereby granted, free of charge, to any person obtaining a copy

of this software and associated documentation files (the "Software"), to deal

in the Software without restriction, including without limitation the rights

to use, copy, modify, merge, publish, distribute, sublicense, and/or sell

copies of the Software, and to permit persons to whom the Software is

furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in

all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR

IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,

FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE

AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER

LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,

OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN

THE SOFTWARE.

*/

import Foundation

public enum ColorCodeType: Int, CaseIterable {

// MARK: Color Components

enum ColorComponents {

extension ColorComponents {

/// Initialize with the given hex color code. Or returns `nil` if color code is invalid.

///

/// Example usage:

/// ```

/// let redComponents = ColorComponents(hex: 0xFF0000)

/// ```

///

/// - Parameters:

/// - hex: The 6-digit hexadecimal color code.

init?(hex: Int) {

guard (0...0xFFFFFF).contains(hex) else {

return nil

}

let r = (hex >> 16) & 0xff

let g = (hex >> 8) & 0xff

let b = (hex) & 0xff

self = .rgb(Double(r) / 255, Double(g) / 255, Double(b) / 255)

}

/// Initialize with the given color code. Or returns `nil` if color code is invalid.

///

/// - Parameters:

/// - colorCode: The CSS3 style color code string. The given code as hex or CSS keyword is case insensitive.

/// - type: Upon return, contains the detected color code type.

init?(colorCode: String, type: inout ColorCodeType?) {

// initialize with `nil` anyway

type = nil

let code = colorCode.trimmingCharacters(in: .whitespacesAndNewlines)

// detect code type

guard let (detectedType, result) = ColorCodeType.allCases.lazy

.compactMap({ type -> (ColorCodeType, NSTextCheckingResult)? in

let pattern: String = {

}()

let regex = try! NSRegularExpression(pattern: pattern)

guard let match = regex.firstMatch(in: code, range: NSRange(0..<code.utf16.count)) else {

return nil

}

return (type, match)

}).first else { return nil }

// create color from result

switch detectedType {

case .hex:

let hex = Int(code.dropFirst(), radix: 16)!

self.init(hex: hex)

case .shortHex:

let hex = Int(code.dropFirst(), radix: 16)!

let r = (hex >> 8) & 0xff

let g = (hex >> 4) & 0xff

let b = (hex) & 0xff

self = .rgb(Double(r) / 15, Double(g) / 15, Double(b) / 15)

case .cssRGB:

guard

let r = result.double(in: code, at: 1),

let g = result.double(in: code, at: 2),

let b = result.double(in: code, at: 3)

else { return nil }

self = .rgb(r / 255, g / 255, b / 255)

case .cssRGBa:

guard

let r = result.double(in: code, at: 1),

let g = result.double(in: code, at: 2),

let b = result.double(in: code, at: 3),

let a = result.double(in: code, at: 4)

else { return nil }

self = .rgb(r / 255, g / 255, b / 255, alpha: a)

case .cssHSL:

guard

let h = result.double(in: code, at: 1),

let s = result.double(in: code, at: 2),

let l = result.double(in: code, at: 3)

else { return nil }

self = .hsl(h / 360, s / 100, l / 100)

case .cssHSLa:

guard

let h = result.double(in: code, at: 1),

let s = result.double(in: code, at: 2),

let l = result.double(in: code, at: 3),

let a = result.double(in: code, at: 4)

else { return nil }

self = .hsl(h / 360, s / 100, l / 100, alpha: a)

case .cssKeyword:

let lowercase = code.lowercased()

guard let hex = colorKeywordMap.first(where: { $0.key.lowercased() == lowercase })?.value else {

return nil

}

self.init(hex: hex)

}

type = detectedType

}

private extension NSTextCheckingResult {

func double(in string: String, at index: Int) -> Double? {

}