import {DOM} from 'angular2/src/platform/dom/dom_adapter';
import {global, isString} from 'angular2/src/facade/lang';
import {StringMapWrapper} from 'angular2/src/facade/collection';


export interface NgMatchers extends jasmine.Matchers {
  toBePromise(): boolean;
  toBeAnInstanceOf(expected: any): boolean;
  toHaveText(expected: any): boolean;
  toHaveCssClass(expected: any): boolean;
  toHaveCssStyle(expected: any): boolean;
  toImplement(expected: any): boolean;
  toContainError(expected: any): boolean;
  toThrowErrorWith(expectedMessage: any): boolean;
  not: NgMatchers;
}

var _global: jasmine.GlobalPolluter = <any>(typeof window === 'undefined' ? global : window);

export var expect: (actual: any) => NgMatchers = <any>_global.expect;


// Some Map polyfills don't polyfill Map.toString correctly, which
// gives us bad error messages in tests.
// The only way to do this in Jasmine is to monkey patch a method
// to the object :-(
Map.prototype['jasmineToString'] = function() {
  var m = this;
  if (!m) {
    return '' + m;
  }
  var res = [];
  m.forEach((v, k) => { res.push(`${k}:${v}`); });
  return `{ ${res.join(',')} }`;
};

_global.beforeEach(function() {
  jasmine.addMatchers({
    // Custom handler for Map as Jasmine does not support it yet
    toEqual: function(util, customEqualityTesters) {
      return {
        compare: function(actual, expected) {
          return {pass: util.equals(actual, expected, [compareMap])};
        }
      };

      function compareMap(actual, expected) {
        if (actual instanceof Map) {
          var pass = actual.size === expected.size;
          if (pass) {
            actual.forEach((v, k) => { pass = pass && util.equals(v, expected.get(k)); });
          }
          return pass;
        } else {
          return undefined;
        }
      }
    },

    toBePromise: function() {
      return {
        compare: function(actual, expectedClass) {
          var pass = typeof actual === 'object' && typeof actual.then === 'function';
          return {pass: pass, get message() { return 'Expected ' + actual + ' to be a promise'; }};
        }
      };
    },

    toBeAnInstanceOf: function() {
      return {
        compare: function(actual, expectedClass) {
          var pass = typeof actual === 'object' && actual instanceof expectedClass;
          return {
            pass: pass,
            get message() {
              return 'Expected ' + actual + ' to be an instance of ' + expectedClass;
            }
          };
        }
      };
    },

    toHaveText: function() {
      return {
        compare: function(actual, expectedText) {
          var actualText = elementText(actual);
          return {
            pass: actualText == expectedText,
            get message() { return 'Expected ' + actualText + ' to be equal to ' + expectedText; }
          };
        }
      };
    },

    toHaveCssClass: function() {
      return {compare: buildError(false), negativeCompare: buildError(true)};

      function buildError(isNot) {
        return function(actual, className) {
          return {
            pass: DOM.hasClass(actual, className) == !isNot,
            get message() {
              return `Expected ${actual.outerHTML} ${isNot ? 'not ' : ''}to contain the CSS class "${className}"`;
            }
          };
        };
      }
    },

    toHaveCssStyle: function() {
      return {
        compare: function(actual, styles) {
          var allPassed;
          if (isString(styles)) {
            allPassed = DOM.hasStyle(actual, styles);
          } else {
            allPassed = !StringMapWrapper.isEmpty(styles);
            StringMapWrapper.forEach(styles, (style, prop) => {
              allPassed = allPassed && DOM.hasStyle(actual, prop, style);
            });
          }

          return {
            pass: allPassed,
            get message() {
              var expectedValueStr = isString(styles) ? styles : JSON.stringify(styles);
              return `Expected ${actual.outerHTML} ${!allPassed ? ' ' : 'not '}to contain the
                      CSS ${isString(styles) ? 'property' : 'styles'} "${expectedValueStr}"`;
            }
          };
        }
      };
    },

    toContainError: function() {
      return {
        compare: function(actual, expectedText) {
          var errorMessage = actual.toString();
          return {
            pass: errorMessage.indexOf(expectedText) > -1,
            get message() { return 'Expected ' + errorMessage + ' to contain ' + expectedText; }
          };
        }
      };
    },

    toThrowErrorWith: function() {
      return {
        compare: function(actual, expectedText) {
          try {
            actual();
            return {
              pass: false,
              get message() { return "Was expected to throw, but did not throw"; }
            };
          } catch (e) {
            var errorMessage = e.toString();
            return {
              pass: errorMessage.indexOf(expectedText) > -1,
              get message() { return 'Expected ' + errorMessage + ' to contain ' + expectedText; }
            };
          }
        }
      };
    },

    toImplement: function() {
      return {
        compare: function(actualObject, expectedInterface) {
          var objProps = Object.keys(actualObject.constructor.prototype);
          var intProps = Object.keys(expectedInterface.prototype);

          var missedMethods = [];
          intProps.forEach((k) => {
            if (!actualObject.constructor.prototype[k]) missedMethods.push(k);
          });

          return {
            pass: missedMethods.length == 0,
            get message() {
              return 'Expected ' + actualObject + ' to have the following methods: ' +
                     missedMethods.join(", ");
            }
          };
        }
      };
    }
  });
});

function elementText(n) {
  var hasNodes = (n) => {
    var children = DOM.childNodes(n);
    return children && children.length > 0;
  };

  if (n instanceof Array) {
    return n.map(elementText).join("");
  }

  if (DOM.isCommentNode(n)) {
    return '';
  }

  if (DOM.isElementNode(n) && DOM.tagName(n) == 'CONTENT') {
    return elementText(Array.prototype.slice.apply(DOM.getDistributedNodes(n)));
  }

  if (DOM.hasShadowRoot(n)) {
    return elementText(DOM.childNodesAsList(DOM.getShadowRoot(n)));
  }

  if (hasNodes(n)) {
    return elementText(DOM.childNodesAsList(n));
  }

  return DOM.getText(n);
}