const runtime = require('node-red').runtime

let oldpath

module.exports = function(RED) {
  function FirebaseAdmin(config) {
    RED.nodes.createNode(this, config);
    var node = this;

    const cb = (res)=>{
      //console.log('firebase get result '+res)
      //console.dir(res)
      if(config.env_var && process.env[config.env_var]){
        let val = res.val()
        runtime.flows.getFlow({id: val.id}).then((flow)=>{
          console.log('rtdb-to-flow old flow updated_at = '+flow.updated_at+' new flow updated_at = '+val.updated_at)
          if(!flow.updated_at || val.updated_at > flow.updated_at){
            console.log('updating flow...')
            runtime.flows.updateFlow({id: val.id, flow: val})
          }
          //console.log('val='+val)
          node.send({payload:val})
        })
      } else {
        console.log('skipping flow update because environment variable '+config.env_var+' was either not defined or not set to true')
      }
    }

    let setUpListener = (path)=>{
      //console.log('rtdb-get setUpListener for path '+path)
      if(oldpath){
        this.admin.database().ref(oldpath).off('value', cb)
      }
      this.admin.database().ref(path).on('value', cb)
      oldpath = path
    }

    if(config.cred){
      let c = RED.nodes.getNode(config.cred)
      this.admin = c.admin
    }

    //console.log('------------------------------- rtdg-get config')
    //console.dir(config)
    this.path = config.path
    if(this.path){
      setUpListener(this.path)
    }


    //console.log('configuring rtdb-get to listen for messages')
    node.on('input', function(msg) {
      let path = this.path
      if(msg && msg.payload){
        path = msg.payload.path
        setUpListener(path)
      }
    }.bind(this));


  }
  RED.nodes.registerType("rtdb-to-flow", FirebaseAdmin);
}