//
//  NotesStorage.swift
//  Peered
//
//  Created by Oskar Chybowski on 25/09/2025.
//

import Foundation

protocol StorageProvider {
  func contentsOfDirectory(atPath path: String) throws -> [String]

  @discardableResult
  func createFile(
    atPath path: String, contents data: Data?, attributes attr: [FileAttributeKey: Any]?
  ) -> Bool
}

extension FileManager: StorageProvider {}

struct NotesStorage {
  let storageProvider: StorageProvider
  let rootDirectory: URL

  init(
    storageProvider: StorageProvider = FileManager.default,
    rootDirectory: URL = .documentsDirectory
  ) {
    self.storageProvider = storageProvider
    self.rootDirectory = rootDirectory
  }

  func loadNotes() -> [Note] {
    let files =
      try! storageProvider
      .contentsOfDirectory(atPath: rootDirectory.path)
    var notes = [Note]()

    for file in files.compactMap({
      URL(
        filePath: $0,
        directoryHint: .notDirectory,
        relativeTo: rootDirectory
      )
    }) {
      let name = file.lastPathComponent
      let note = Note(
        name: name,
        path: file
      )
      notes.append(note)
    }

    return notes
  }

  func createNote(name: String) {
    let currentNotes = loadNotes()
    var index: Int? = nil
    var proposedName: String {
      index.map { name + " \($0)" } ?? name
    }

    while currentNotes.contains(where: { $0.name == proposedName }) {
      if let _index = index {
        index = _index + 1
      } else {
        index = 1
      }
    }

    let pathToWrite =
      rootDirectory
      .appendingPathComponent(proposedName)
      .appendingPathExtension(for: .text)

    storageProvider.createFile(
      atPath: pathToWrite.path,
      contents: Data(),
      attributes: nil
    )
  }
}