import {isPresent, RegExpWrapper} from 'angular2/src/facade/lang';
import {MapWrapper} from 'angular2/src/facade/collection';

import {Parser} from 'angular2/change_detection';

import {CompileStep} from './compile_step';
import {CompileElement} from './compile_element';
import {CompileControl} from './compile_control';

import {dashCaseToCamelCase} from '../util';

// Group 1 = "bind-"
// Group 2 = "var-" or "#"
// Group 3 = "on-"
// Group 4 = "bindon-"
// Group 5 = the identifier after "bind-", "var-/#", or "on-"
// Group 6 = idenitifer inside [()]
// Group 7 = idenitifer inside []
// Group 8 = identifier inside ()
var BIND_NAME_REGEXP = RegExpWrapper.create(
    '^(?:(?:(?:(bind-)|(var-|#)|(on-)|(bindon-))(.+))|\\[\\(([^\\)]+)\\)\\]|\\[([^\\]]+)\\]|\\(([^\\)]+)\\))$');
/**
 * Parses the property bindings on a single element.
 */
export class PropertyBindingParser implements CompileStep {
  _parser: Parser;

  constructor(parser: Parser) { this._parser = parser; }

  process(parent: CompileElement, current: CompileElement, control: CompileControl) {
    var attrs = current.attrs();
    var newAttrs = MapWrapper.create();

    MapWrapper.forEach(attrs, (attrValue, attrName) => {
      var bindParts = RegExpWrapper.firstMatch(BIND_NAME_REGEXP, attrName);
      if (isPresent(bindParts)) {
        if (isPresent(bindParts[1])) {  // match: bind-prop
          this._bindProperty(bindParts[5], attrValue, current, newAttrs);

        } else if (isPresent(
                       bindParts[2])) {  // match: var-name / var-name="iden" / #name / #name="iden"
          var identifier = bindParts[5];
          var value = attrValue == '' ? '\$implicit' : attrValue;
          this._bindVariable(identifier, value, current, newAttrs);

        } else if (isPresent(bindParts[3])) {  // match: on-event
          this._bindEvent(bindParts[5], attrValue, current, newAttrs);

        } else if (isPresent(bindParts[4])) {  // match: bindon-prop
          this._bindProperty(bindParts[5], attrValue, current, newAttrs);
          this._bindAssignmentEvent(bindParts[5], attrValue, current, newAttrs);

        } else if (isPresent(bindParts[6])) {  // match: [(expr)]
          this._bindProperty(bindParts[6], attrValue, current, newAttrs);
          this._bindAssignmentEvent(bindParts[6], attrValue, current, newAttrs);

        } else if (isPresent(bindParts[7])) {  // match: [expr]
          this._bindProperty(bindParts[7], attrValue, current, newAttrs);

        } else if (isPresent(bindParts[8])) {  // match: (event)
          this._bindEvent(bindParts[8], attrValue, current, newAttrs);
        }
      } else {
        var expr = this._parser.parseInterpolation(attrValue, current.elementDescription);
        if (isPresent(expr)) {
          this._bindPropertyAst(attrName, expr, current, newAttrs);
        }
      }
    });

    MapWrapper.forEach(newAttrs,
                       (attrValue, attrName) => { MapWrapper.set(attrs, attrName, attrValue); });
  }

  _bindVariable(identifier, value, current: CompileElement, newAttrs) {
    current.bindElement().bindVariable(dashCaseToCamelCase(identifier), value);
    MapWrapper.set(newAttrs, identifier, value);
  }

  _bindProperty(name, expression, current: CompileElement, newAttrs) {
    this._bindPropertyAst(name, this._parser.parseBinding(expression, current.elementDescription),
                          current, newAttrs);
  }

  _bindPropertyAst(name, ast, current: CompileElement, newAttrs) {
    var binder = current.bindElement();
    var camelCaseName = dashCaseToCamelCase(name);
    binder.bindProperty(camelCaseName, ast);
    MapWrapper.set(newAttrs, name, ast.source);
  }

  _bindAssignmentEvent(name, expression, current: CompileElement, newAttrs) {
    this._bindEvent(name, `${expression}=$event`, current, newAttrs);
  }

  _bindEvent(name, expression, current: CompileElement, newAttrs) {
    current.bindElement().bindEvent(
        dashCaseToCamelCase(name),
        this._parser.parseAction(expression, current.elementDescription));
    // Don't detect directives for event names for now,
    // so don't add the event name to the CompileElement.attrs
  }
}