//
//  main.swift
//  
//
//  Created by Thibaut Schmitt on 20/12/2021.
//

import Foundation
import ToolCore
import ArgumentParser

enum ColorStyle: String, Decodable {
    case light
    case all
}

struct ColorTool: ParsableCommand {
    static let defaultExtensionName = "UIColor"
    static let assetsColorsFolderName = "Colors"
    
    @OptionGroup var options: ColorToolOptions
    
    var colorStyle: ColorStyle { ColorStyle(rawValue: options.style) ?? .all }
    var extensionFileName: String { "\(options.extensionName)+\(options.extensionSuffix).swift" }
    var extensionFilePath: String { "\(options.extensionOutputPath)/\(extensionFileName)" }
    
    public func run() throws {
        print("[ColorTool] Starting colors generation")
        
        print("[ColorTool] Will use inputFile \(options.inputFile) to generate \(colorStyle) colors in xcassets \(options.xcassetsPath)")
        print("[ColorTool] Extension will be \(extensionFilePath)")
        
        // Check requirements
        let fileManager = FileManager()
        guard fileManager.fileExists(atPath: options.xcassetsPath) else {
            let error = ColorToolError.fileNotExists(options.xcassetsPath)
            print(error.localizedDescription)
            ColorTool.exit(withError: error)
        }
        guard fileManager.fileExists(atPath: options.inputFile) else {
            let error = ColorToolError.fileNotExists(options.inputFile)
            print(error.localizedDescription)
            ColorTool.exit(withError: error)
        }

        // Check if needed to regenerate
        guard GeneratorChecker.shouldGenerate(force: options.forceGeneration, inputFilePath: options.inputFile, extensionFilePath: extensionFilePath) else {
            print("[ColorTool] Colors are already up to date :) ")
            return
        }
        print("[ColorTool] Will generate colors")
        
        // Delete current colors
        Shell.shell("rm", "-rf", "\(options.xcassetsPath)/Colors/*")
        
        // Get colors
        let colorsToGen = getColorsGen()
        
        // Generate all colors in xcassets
        let colorAssetHelper = ColorXcassetHelper(xcassetsPath: options.xcassetsPath, colors: colorsToGen)
        colorAssetHelper.generateXcassetColors()
        
        // Generate extension
        let extensionGenerator = ColorExtensionGenerator(colors: colorsToGen,
                                                         extensionClassname: options.extensionName,
                                                         isUIColorExtension: isUIColorExtension())
        let extensionHeader = extensionGenerator.getHeader()
        let extensionProperties = extensionGenerator.getProperties()
        let extensionFooter = extensionGenerator.getFooter()
        
        generateExtensionFile(extensionHeader, extensionProperties, extensionFooter)
        
        print("[ColorTool] Colors generated")
    }
    
    private func generateExtensionFile(_ args: String...) {
        // Create file if not exists
        let fileManager = FileManager()
        if fileManager.fileExists(atPath: extensionFilePath) == false {
            Shell.shell("touch", "\(extensionFilePath)")
        }
        
        // Create extension content
        let extensionContent = args.joined(separator: "\n")
        
        // Write content
        let extensionFilePathURL = URL(fileURLWithPath: extensionFilePath)
        do {
            try extensionContent.write(to: extensionFilePathURL, atomically: true, encoding: .utf8)
        } catch (let error) {
            let error = ColorToolError.writeExtension(extensionFilePath, error.localizedDescription)
            print(error.localizedDescription)
            ColorTool.exit(withError: error)
        }
    }
    
    private func getColorsGen() -> [GenColor] {
        // Get content of input file
        let inputFileContent = try! String(contentsOfFile: options.inputFile, encoding: .utf8)
        let colorsByLines = inputFileContent.components(separatedBy: CharacterSet.newlines)
        
        // Iterate on each line of input file
        return colorsByLines.enumerated().compactMap { lineNumber, colorLine in
            // Required format:
            // colorName="#RGB/#ARGB", colorName "#RGB/#ARGB", colorName "#RGB/#ARGB" "#RGB/#ARGB"
            let colorLineCleanedUp = colorLine
                .removeTrailingWhitespace()
                .replacingOccurrences(of: "=", with: "") // Keep compat with current file format
            
            guard colorLineCleanedUp.hasPrefix("#") == false, colorLineCleanedUp.isEmpty == false else {
                print("[ColorTool] ⚠️  BadFormat or empty line (line number: \(lineNumber + 1)). Skip this line")
                return nil
            }
            
            let colorContent = colorLineCleanedUp.split(separator: " ")
            
            guard colorContent.count >= 2 else {
                let error = ColorToolError.badFormat(colorLine)
                print(error.localizedDescription)
                ColorTool.exit(withError: error)
            }
            
            switch colorStyle {
            case .light:
                return GenColor(name: String(colorContent[0]), light: String(colorContent[1]), dark: String(colorContent[1]))
                
            case .all:
                if colorContent.count == 3 {
                    return GenColor(name: String(colorContent[0]), light: String(colorContent[1]), dark: String(colorContent[2]))
                }
                return GenColor(name: String(colorContent[0]), light: String(colorContent[1]), dark: String(colorContent[1]))
            }
        }
    }
    
    // MARK: - Helpers
    
    private func isUIColorExtension() -> Bool {
        options.extensionName == Self.defaultExtensionName
    }
}

ColorTool.main()

/*
 Command samples:
 
 1. UIColor extension without suffix
 swift run -c release ColorToolCore -f ./SampleFiles/Colors/sampleColors1.txt --style all --xcassets-path "./SampleFiles/Colors/colors.xcassets" --extension-output-path "./SampleFiles/Colors/Generated/" --extension-name "UIColor"
 
 2. UIColor extension with custom suffix
 swift run -c release ColorToolCore -f ./SampleFiles/Colors/sampleColors1.txt --style all --xcassets-path "./SampleFiles/Colors/colors.xcassets" --extension-output-path "./SampleFiles/Colors/Generated/" --extension-name "UIColor" --extension-suffix "SampleApp"
 
 3. Custom extension with only light theme colors (R2Color)
 swift run -c release ColorToolCore -f ./SampleFiles/Colors/sampleColors1.txt --style light --xcassets-path "./SampleFiles/Colors/colors.xcassets" --extension-output-path "./SampleFiles/Colors/Generated/" --extension-name "R2Color"
 */