Stone Collection: An extremely simple persistent collection - written in stone.

StoneCollection.js

/*

  usage: 

  Tables = new Stone.Collection('tables');  // create a stone collection
  Profile = new Stone.Singleton('');        // create a stone singleton

  ------- shared API -------
    get()      returns all in DB
    set(obj)   sets entire DB to obj
    update(modifier) modify the entry
  
  ------- API for collections only ------
    find(selector)   find documents matching selector (not yet implemented, currently returns everything)
    findOne(id)    find one document with id
    update(id, obj)  updates document with id to obj
    insert(obj)    inserts new obj to DB
    remove(id)   removes document with id
*/

var StoneCollection = class {
  
  constructor(label){
    // constructs new LucDB. Needs a label passed
    if(! label){
      alert('You are a fool. You have not provided a label');
      return;
    }
    this.label = label;
    this.dependency = new Tracker.Dependency;
    
    if(!localStorage[label]){
      localStorage[label] = JSON.stringify([]);
    } 
  }

  set(obj){
    // Sets entire collection to obj! Often used for singletons
    if(!obj._id){
      obj._id = Random.id();
    }
    if(obj.constructor == Array){
      obj.forEach(function(o){
        if(!o._id){
          o._id = Random.id();
        }
      });
    }
    localStorage[this.label] = JSON.stringify(obj);
    this.dependency.changed();
  }

  get(){
    // Returns everything in collection
    this.dependency.depend();
    if(localStorage[this.label]){
      return JSON.parse(localStorage[this.label]);
    }
  }

  find(selector){
    // TODO
    // Finds all that match selector. Foolish if it is a singleton
    this.dependency.depend();
    if(!localStorage[this.label]) return null;
    var everything = JSON.parse(localStorage[this.label]);
    var notEverything = [];

    // filter stuff

    notEverything = everything;

    return notEverything;
  }

  findOne(id){
    // takes id and returns one document. Foolish if it is a singleton
    this.dependency.depend();
    var everything = JSON.parse(localStorage[this.label]);
    var result;
    everything.forEach(function(obj){
      if(obj._id == id){
        result = obj;
      }
    });

    return result;
  }

  update(id, obj){
    // updates the one with id to new one. Foolish if singleton
    obj._id = id;
    var everything = JSON.parse(localStorage[this.label]);

    for(var i=0; i < everything.length; i++){
      if(everything[i]._id == id){
        everything[i] = obj;
      }
    }
    this.set(everything);
  }

  insert(obj){
    // Inserts something into collection. Foolish if collection is a singleton
    var before = this.get();
    if(! before.push){
      alert('You fool! This is a singleton! You cannot push objects into this');
      return;
    }
    obj._id = Random.id();
    before.push(obj);
    var after = before;
    this.set(after);
  }

  remove(id){
    // removes doc with _id: id
    var tables = this.get();
    for(var i=0; i < tables.length; i++){
      if(tables[i]._id == id){
        tables.splice(i,1);
      }
    }
    this.set(tables);
  }

  count(){
    this.dependency.changed();
    var everything = JSON.parse(localStorage[this.label]);
    return everything.length;
  }
}


var StoneSingleton = class {
  
  constructor(label){
    // constructs new LucDB. Needs a label passed
    if(! label){
      alert('You are a fool. You have not provided a label');
      return;
    }
    this.label = label;
    this.dependency = new Tracker.Dependency;
    
    if(!localStorage[label]){
      localStorage[label] = JSON.stringify({_id: Random.id()});
    } 
  }

  update(modifier) {
    // updates the singleton with a modifier
    const keys = Object.keys(modifier);
    let entry = JSON.parse(localStorage[this.label]);
    keys.forEach(key => {
      const value = modifier[key];
      entry[key] = value;
    });
    this.set(entry);
  }

  set(obj){
    // Sets entire collection to obj! 
    if(!obj._id){
      obj._id = Random.id();
    }
    if(obj.constructor == Array){
      obj.forEach(function(o){
        if(!o._id){
          o._id = Random.id();
        }
      });
    }
    localStorage[this.label] = JSON.stringify(obj);
    this.dependency.changed();
  }

  get(){
    // Returns everything in collection
    this.dependency.depend();
    if(localStorage[this.label]){
      return JSON.parse(localStorage[this.label]);
    }
  }
}


Stone = {
  Collection: StoneCollection,
  Singleton: StoneSingleton
}