als-path-tree/lib/file.js

A Node.js library for managing a virtual file system structure, offering functionalities for file and directory operations with a shared storage system.

const Item = require('./item')

class File extends Item {
   constructor(name, meta, parent, content) {
      super(name, parent, true)
      if (parent) parent.files[name] = this
      this.meta = {}
      this.save(content)
      this.meta = this.prepareMeta(meta);
      this.accessCount = 0;
   }

   prepareMeta(meta = {}) {
      return {
         mtimeMs: meta.mtimeMs || Date.now(),
         atimeMs: meta.atimeMs || Date.now(),
         size: meta.size || (this._buffer ? this._buffer.length : 0) 
      };
   }

   get buffer() { 
      this.accessCount++
      return this._buffer 
   }

   save(value) {
      if(value === null || value === undefined) {
         this._buffer = null
         this.meta.size = 0
         this.main.memMonitor.remove(this)
         return
      }
      const buffer = this.compare(value)
      if (buffer === false) return
      this._buffer = value
      this.meta.size = this._buffer.length
      this.accessCount++
      this.main.memMonitor.add(this)
   }

   compare(content) {
      const isBuffer = Buffer.isBuffer(content);
      const isString = typeof content === 'string'
      if(!isBuffer && !isString) return false
      if(isString) content = Buffer.from(content)
      if (Buffer.isBuffer(this._buffer) && Buffer.compare(this._buffer, content) === 0) return false;
      return content
   }

   get lastAccessTime() { return this.meta.atimeMs || this.meta.mtimeMs; }
   get age() { return (Date.now() - this.lastAccessTime) / (1000 * 60 * 60); } // Возраст в часах

   get content() { return this._buffer ? this.buffer.toString() : null }
   get json() { return this._buffer ? JSON.parse(this.content) : null }

   delete() {
      if (!this.parent) return
      delete this.parent.files[this.name]
      this.main.memMonitor.remove(this)
      this.parent.removeIfEmpty()
   }

   copyTo(destPath) { this.root.addFile(destPath, { size: this.size }, this.buffer) }

   moveTo(destPath) {
      if(!this.parent) return
      const { parts, filename } = this.splitPath(destPath)
      const newParent = this.root.addDir(parts)
      if(newParent === this.parent) this.rename(destPath)
      newParent.files[filename] = this
      this.name = filename
   }

}

module.exports = File