//
//  StringsFileGenerator.swift
//  
//
//  Created by Thibaut Schmitt on 04/01/2022.
//

import Foundation
import CLIToolCore

extension Strings {
    class StringsFileGenerator {
        
        // MARK: - Strings Files
        
        static func writeStringsFiles(sections: [Section], langs: [String], defaultLang: String, tags: [String], outputPath: String, inputFilenameWithoutExt: String) {
            var stringsFilesContent = [String: String]()
            for lang in langs {
                stringsFilesContent[lang] = Self.generateStringsFileContent(lang: lang,
                                                                            defaultLang: defaultLang,
                                                                            tags: tags,
                                                                            sections: sections)
            }
            
            // Write strings file content
            langs.forEach { lang in
                guard let fileContent = stringsFilesContent[lang] else { return }
                
                let stringsFilePath = "\(outputPath)/\(lang).lproj/\(inputFilenameWithoutExt).strings"
                let stringsFilePathURL = URL(fileURLWithPath: stringsFilePath)
                do {
                    try fileContent.write(to: stringsFilePathURL, atomically: true, encoding: .utf8)
                } catch (let error) {
                    let error = StringiumError.writeFile(error.localizedDescription, stringsFilePath)
                    print(error.localizedDescription)
                    Stringium.exit(withError: error)
                }
            }
        }
        
        private static func generateStringsFileContent(lang: String, defaultLang: String, tags inputTags: [String], sections: [Section]) -> String {
            var stringsFileContent = """
        /**
         * Apple Strings File
         * Generated by ResgenSwift 1.0.0
         * Language: \(lang)
         */\n
        """
            
            sections.forEach { section in
                // Check that at least one string will be generated
                guard section.hasOneOrMoreMatchingTags(tags: inputTags) else {
                    return // Go to next section
                }
                
                stringsFileContent += "\n/********** \(section.name) **********/\n\n"
                section.definitions.forEach { definition in
                    let translationOpt: String? = {
                        if definition.tags.contains(Stringium.noTranslationTag) {
                            return definition.translations[defaultLang]
                        }
                        return definition.translations[lang]
                    }()
                    
                    if let translation = translationOpt {
                        stringsFileContent += "\"\(definition.name)\" = \"\(translation)\"\n\n"
                    } else {
                        let error = StringiumError.langNotDefined(lang, definition.name, definition.reference != nil)
                        print(error.localizedDescription)
                        Stringium.exit(withError: error)
                    }
                }
            }
            
            return stringsFileContent
        }
        
        // MARK: - Extension file
        
        static func writeExtensionFiles(sections: [Section], defaultLang lang: String, tags: [String], staticVar: Bool, inputFilename: String, extensionName: String, extensionFilePath: String) {
            let extensionHeader = Self.getHeader(stringsFilename: inputFilename, extensionClassname: extensionName)
            let extensionFooter = Self.getFooter()
            
            let extensionContent: String = {
                var content = ""
                sections.forEach { section in
                    // Check that at least one string will be generated
                    guard section.hasOneOrMoreMatchingTags(tags: tags) else {
                        return // Go to next section
                    }
                    
                    content += "\n\t// MARK: - \(section.name)"
                    section.definitions.forEach { definition in
                        if staticVar {
                            content += "\n\n\(definition.getNSLocalizedStringStaticProperty(forLang: lang))"
                        } else {
                            content += "\n\n\(definition.getNSLocalizedStringProperty(forLang: lang))"
                        }
                    }
                    content += "\n"
                }
                return content
            }()
            
            // Create file if not exists
            let fileManager = FileManager()
            if fileManager.fileExists(atPath: extensionFilePath) == false {
                Shell.shell("touch", "\(extensionFilePath)")
            }
            
            // Create extension content
            let extensionFileContent = [extensionHeader, extensionContent, extensionFooter].joined(separator: "\n")
            
            // Write content
            let extensionFilePathURL = URL(fileURLWithPath: extensionFilePath)
            do {
                try extensionFileContent.write(to: extensionFilePathURL, atomically: true, encoding: .utf8)
            } catch (let error) {
                let error = StringiumError.writeFile(extensionFilePath, error.localizedDescription)
                print(error.localizedDescription)
                Stringium.exit(withError: error)
            }
        }
        
        private static func getHeader(stringsFilename: String, extensionClassname: String) -> String {
        """
        // Generated from Strings-Stringium at \(Date())
        
        import UIKit
        
        fileprivate let kStringsFileName = "\(stringsFilename)"
        
        extension \(extensionClassname) {
        """
        }
        
        private static func getFooter() -> String {
        """
        }
        """
        }
    }
}