const {buildOptions,registerCommonValueParsers} = require("./ParserOptionsBuilder");

class OutputBuilder{
  constructor(builderOptions){
      this.options = buildOptions(builderOptions);
      this.registeredParsers = registerCommonValueParsers(this.options);
  }

  registerValueParser(name,parserInstance){//existing name will override the parser without warning
    this.registeredParsers[name] = parserInstance;
  }

  getInstance(parserOptions){
    return new JsObjBuilder(parserOptions, this.options, this.registeredParsers);
  }
}

const BaseOutputBuilder = require("./BaseOutputBuilder");
const rootName = '^';

class JsObjBuilder extends BaseOutputBuilder{

  constructor(parserOptions, builderOptions,registeredParsers) {
    super();
    //hold the raw detail of a tag and sequence with reference to the output
    this.tagsStack = [];
    this.parserOptions = parserOptions;
    this.options = builderOptions;
    this.registeredParsers = registeredParsers;

    this.root = {};
    this.parent = this.root;
    this.tagName = rootName;
    this.value = {};
    this.textValue = "";
    this.attributes = {};
  }

  addTag(tag){

    let value = "";
    if( !isEmpty(this.attributes)){
      value = {};
      if(this.options.attributes.groupBy){
        value[this.options.attributes.groupBy] = this.attributes;
      }else{
        value = this.attributes;
      }
    }

    this.tagsStack.push([this.tagName, this.textValue, this.value]); //parent tag, parent text value, parent tag value (jsobj)
    this.tagName = tag.name;
    this.value = value;
    this.textValue = "";
    this.attributes = {};
  }

  /**
   * Check if the node should be added by checking user's preference
   * @param {Node} node 
   * @returns boolean: true if the node should not be added
   */
  closeTag(){
    const tagName = this.tagName;
    let value = this.value;
    let textValue = this.textValue;

    //update tag text value
    if(typeof value !== "object" && !Array.isArray(value)){
      value = this.parseValue(textValue.trim(), this.options.tags.valueParsers);
    }else if(textValue.length > 0){
      value[this.options.nameFor.text] = this.parseValue(textValue.trim(), this.options.tags.valueParsers);
    }

    
    let resultTag= {
      tagName: tagName,
      value: value
    };

    if(this.options.onTagClose !== undefined){
      //TODO TagPathMatcher 
      resultTag = this.options.onClose(tagName, value, this.textValue, new TagPathMatcher(this.tagsStack,node));

      if(!resultTag) return;
    }

    //set parent node in scope
    let arr = this.tagsStack.pop(); 
    let parentTag = arr[2];
    parentTag=this._addChildTo(resultTag.tagName, resultTag.value, parentTag);

    this.tagName = arr[0];
    this.textValue = arr[1];
    this.value = parentTag;
  }

  _addChild(key, val){
    if(typeof this.value === "string"){
      this.value = { [this.options.nameFor.text] : this.value };
    }

    this._addChildTo(key, val, this.value);
    // this.currentNode.leafType = false;
    this.attributes = {};
  }

  _addChildTo(key, val, node){
    if(typeof node === 'string') node = {};
    if(!node[key]){
      node[key] = val;
    }else{ //Repeated
      if(!Array.isArray(node[key])){ //but not stored as array
        node[key] = [node[key]];
      }
      node[key].push(val);
    }
    return node;
  }


  /**
   * Add text value child node 
   * @param {string} text 
   */
  addValue(text){
    //TODO: use bytes join
    if(this.textValue.length > 0) this.textValue += " " + text;
    else this.textValue = text;
  }

  addPi(name){
    let value = "";
    if( !isEmpty(this.attributes)){
      value = {};
      if(this.options.attributes.groupBy){
        value[this.options.attributes.groupBy] = this.attributes;
      }else{
        value = this.attributes;
      }
    }
    this._addChild(name, value);
    
  }
  getOutput(){
    return this.value;
  }
}

function isEmpty(obj) {
  return Object.keys(obj).length === 0;
}

module.exports = OutputBuilder;