//
//  GeneratorFontCheck.swift
//  
//
//  Created by Thibaut Schmitt on 22/12/2021.
//

import Foundation

class GeneratorFontChecker {
    
    /// Will check if first line contains exactly all font filenames and nothinf more
    static func shouldGenerate(force: Bool, inputFilenames: [String], extensionFilePath: String) -> Bool {
        guard force == false else {
            return true
        }
        
        let fileManager = FileManager()
        guard fileManager.fileExists(atPath: extensionFilePath) else {
            return true
        }
        
        let extensionFileContent = try! String(contentsOfFile: extensionFilePath, encoding: .utf8)
        
        guard let extensionComparableLine = extensionFileContent.components(separatedBy: .newlines).first else {
            // First line to compare unavailable -> force generation
            return true
        }
        
        let extensionFontNames: [String] = extensionComparableLine
            .split(separator: " ")
            .dropFirst()
            .map { String($0) }
        
        // If count is different, some fonts has been added or removed
        if inputFilenames.count != extensionFontNames.count {
            return true
        }
        
        // Same number of elements, check if all fonts to generate has been already generated in extension
        for inputFile in inputFilenames {
            if extensionFontNames.contains(inputFile) == false {
                return true
            }
        }
        
        return false
    }
}