import { BehaviorInstruction } from 'aurelia-templating';
import { AUController, ViewSlotCorrect, ViewCorrect, ViewFactoryWithTemplate, ViewResources, HtmlBehaviorResourceCorrect } from './_typings'

export interface TraversalInfo {
  parentController: AUController;
  // lookFor: 'function' | 'instance';
  previouslyTraversed: Set<any>;
  immediateParent?: any;
  propertyInParent?: string | number;
  childOfViewSlot?: ViewSlotCorrect;
  relatedView?: ViewCorrect;
  instance?: boolean;
  duplicate?: boolean;
}

/**
 *  traverse interesting places in Controller:
 * - behavior.target (class of ViewModel)
 * - behavior.viewFactory (traverse ViewFactory)
 * - behavior.attributes[array] (?)
 * 
 * - viewFactory.instructions[ALL-obj].providers[ALL-arr] (original functions/classes, not instances, things like If)
 * - viewFactory.instructions[ALL-obj].viewFactory
 * 
 * - viewFactory.resources (ViewResources)
 *      .bindingBehaviors[name] (instances, can fix up .constructor is class)
 *      .valueConverters[name] (instances, can fix up .constructor is class)
 * 
 * - boundProperties[array] ??
 * - container //how can we replace instances in container?
 * - container.children[array<ViewSlot>]?
 * - container
 *      .viewModel? (instance)
 *      .viewResources (ViewResources)
 * 
 * - instruction (BehaviorInstruction)
 *      .viewFactory
 *      .viewModel (instance)
 * 
 * - scope (View)
 *      .bindingContext (instance)
 *      .children[array<ViewSlot>]
 *      .controller (Controller)
 *      .controllers[array<Controller>]
 *      .overrideContext
 *         .bindingContext? (Instance)
 *         .parentOverrideContext
 *               .bindingContext? (and so on...)
 *      .resources (ViewResources)
 *      .viewFactory (ViewFactory)
 * - view (View)
 * - viewModel (instance or RouterView:)
 *      .overrideContext
 *      .router.viewPorts[ALL-obj]. (RouterView)
 *               .overrideContext
 *               .owningView (View)
 *               .view (View)
 *               .viewSlot (ViewSlot)
 *                     .children[array<View>]
 *                     .bindingContext (instance)
 *                     .overrideContext
 **/
export function traverseController(classOrFunction: any, controller: AUController, info: TraversalInfo) {
  const matches = [] as Array<TraversalInfo>
  if (!controller || info.previouslyTraversed.has(controller)) return matches;
  info.previouslyTraversed.add(controller);

  matches.push(
    ...traverseBehaviorResource(
      classOrFunction, controller.behavior as HtmlBehaviorResourceCorrect, { ...info, parentController: controller, immediateParent: controller, propertyInParent: 'behavior' }
    ),
    ...traverseBehaviorInstruction(
      classOrFunction, controller.instruction, { ...info, parentController: controller, immediateParent: controller, propertyInParent: 'instruction' }
    ),
    ...traverseView(
      classOrFunction, controller.scope, { ...info, parentController: controller, immediateParent: controller, propertyInParent: 'scope' }
    ),
    ...traverseView(
      classOrFunction, controller.view, { ...info, parentController: controller, immediateParent: controller, propertyInParent: 'view' }
    ),
    ...traverseViewModel(
      classOrFunction, controller.viewModel, { ...info, parentController: controller, immediateParent: controller, propertyInParent: 'viewModel' }
    )
  )
  return matches;
}

export function traverseBehaviorResource(classOrFunction: any, behavior: HtmlBehaviorResourceCorrect, info: TraversalInfo) {
  const matches = [] as Array<TraversalInfo>
  if (!behavior || info.previouslyTraversed.has(behavior)) return matches;
  info.previouslyTraversed.add(behavior);
  if (behavior.target === classOrFunction) {
    matches.push({ ...info, immediateParent: behavior, propertyInParent: 'target' })
  }
  matches.push(
    ...traverseViewFactory(
      classOrFunction, behavior.viewFactory, { ...info, immediateParent: behavior, propertyInParent: 'viewFactory' }
    )
  );
  
  return matches;
}

export function traverseViewFactory(classOrFunction: any, viewFactory: ViewFactoryWithTemplate, info: TraversalInfo) {
  const matches = [] as Array<TraversalInfo>
  if (!viewFactory || info.previouslyTraversed.has(viewFactory)) return matches;
  info.previouslyTraversed.add(viewFactory);
  if (viewFactory.instructions) {
    Object.keys(viewFactory.instructions).forEach(instructionKey => {
      const instruction = viewFactory.instructions[instructionKey]
      matches.push(...traverseViewFactory(
        classOrFunction, instruction.viewFactory, { ...info, immediateParent: instruction, propertyInParent: 'viewFactory' }
      ));
      if (instruction.providers && instruction.providers.length) {
        (instruction.providers as Array<any>).forEach((providerKey, index) => {
          if (providerKey === classOrFunction) {
            matches.push({ ...info, immediateParent: instruction.providers, propertyInParent: index })
          }
        });
      }
    });
  }
  if (viewFactory.resources) {
    matches.push(
      ...traverseViewResources(classOrFunction, viewFactory.resources, { ...info, immediateParent: viewFactory, propertyInParent: 'resources' })
    )
  }
  return matches;
}

export function traverseViewResources(classOrFunction: any, viewResources: ViewResources | undefined, info: TraversalInfo) {
  const matches = [] as Array<TraversalInfo>
  if (!viewResources || info.previouslyTraversed.has(viewResources)) return matches;
  info.previouslyTraversed.add(viewResources);
  ['bindingBehaviors', 'valueConverters'].forEach(type => {
    const viewResourceInstances = (viewResources as any)[type];
    if (viewResourceInstances) {
      Object.keys(viewResourceInstances).forEach(key => {
        const instance = viewResourceInstances[key];
        if (instance && instance.constructor === classOrFunction) {
          matches.push({ ...info, immediateParent: viewResourceInstances, propertyInParent: key, instance: true });
        }
      });
    }
  });
  matches.push(
    ...traverseViewResources(classOrFunction, viewResources.parent, { ...info, immediateParent: viewResources, propertyInParent: 'parent' })
  )
  return matches;
}

export function traverseBehaviorInstruction(classOrFunction: any, behaviorInstruction: BehaviorInstruction | undefined, info: TraversalInfo) {
  const matches = [] as Array<TraversalInfo>;
  if (!behaviorInstruction || info.previouslyTraversed.has(behaviorInstruction)) return matches;
  info.previouslyTraversed.add(behaviorInstruction);
  matches.push(
    ...traverseViewFactory(
      classOrFunction,
      behaviorInstruction.viewFactory as ViewFactoryWithTemplate,
      { ...info, immediateParent: behaviorInstruction, propertyInParent: 'viewFactory' }
    ),
    ...traverseViewModel(
      classOrFunction,
      behaviorInstruction.viewModel as ViewFactoryWithTemplate,
      { ...info, immediateParent: behaviorInstruction, propertyInParent: 'viewModel' }
    )
  );
  return matches;
}

export function traverseViewModel(classOrFunction: any, viewModel: any, info: TraversalInfo) {
  const matches = [] as Array<TraversalInfo>;
  if (!viewModel) return matches;
  const duplicate = info.previouslyTraversed.has(viewModel);
  info.previouslyTraversed.add(viewModel);

  if (viewModel.constructor === classOrFunction) {
    matches.push({ ...info, instance: true, duplicate });
    if (duplicate) {
      return matches;
    }
  }
  matches.push(
    ...traverseOverrideContext(
      classOrFunction,
      viewModel.overrideContext,
      { ...info, immediateParent: viewModel, propertyInParent: 'overrideContext' }
    ),
    ...traverseRouter(
      classOrFunction,
      viewModel.router,// as RouterView,
      { ...info, immediateParent: viewModel, propertyInParent: 'router' }
    )
  );
  return matches;
}

export function traverseRouter(classOrFunction: any, router: any, info: TraversalInfo) {
  const matches = [] as Array<TraversalInfo>;
  if (!router || info.previouslyTraversed.has(router)) return matches;
  info.previouslyTraversed.add(router);
  if (router.viewPorts) {
    Object.keys(router.viewPorts).forEach(key => {
      const viewPort = router.viewPorts[key];// as RouterView;
      matches.push(
        ...traverseRouterView(
          classOrFunction,
          viewPort,
          { ...info, immediateParent: router.viewPorts, propertyInParent: key }
        ),
      )
    });
  }
  return matches;
}

export function traverseRouterView(classOrFunction: any, routerView: any, info: TraversalInfo) {
  const matches = [] as Array<TraversalInfo>;
  if (!routerView || info.previouslyTraversed.has(routerView)) return matches;
  info.previouslyTraversed.add(routerView);

  matches.push(
    ...traverseOverrideContext(
      classOrFunction,
      routerView.overrideContext,
      { ...info, immediateParent: routerView, propertyInParent: 'overrideContext' }
    ),
    ...traverseView(
      classOrFunction,
      routerView.owningView as ViewCorrect,
      { ...info, immediateParent: routerView, propertyInParent: 'owningView' }
    ),
    ...traverseView(
      classOrFunction,
      routerView.view as ViewCorrect,
      { ...info, immediateParent: routerView, propertyInParent: 'view' }
    ),
    ...traverseViewSlot(
      classOrFunction,
      routerView.viewSlot as ViewSlotCorrect,
      { ...info, immediateParent: routerView, propertyInParent: 'viewSlot' }
    )
  );
  return matches;
}

export function traverseView(classOrFunction: any, view: ViewCorrect, info: TraversalInfo) {
  const matches = [] as Array<TraversalInfo>;
  if (!view || info.previouslyTraversed.has(view)) return matches;
  info.previouslyTraversed.add(view);
  matches.push(
    ...traverseViewModel(
      classOrFunction,
      view.bindingContext,
      { ...info, relatedView: view, immediateParent: view, propertyInParent: 'bindingContext' }
    ),
    ...traverseController(
      classOrFunction,
      view.controller,
      { ...info, relatedView: view, immediateParent: view, propertyInParent: 'controller' }
    ),
    ...traverseOverrideContext(
      classOrFunction,
      view.overrideContext,
      { ...info, relatedView: view, immediateParent: view, propertyInParent: 'overrideContext' }
    ),
    ...traverseViewResources(
      classOrFunction,
      view.resources,
      { ...info, relatedView: view, immediateParent: view, propertyInParent: 'resources' }
    ),
    ...traverseViewFactory(
      classOrFunction,
      view.viewFactory as ViewFactoryWithTemplate,
      { ...info, relatedView: view, immediateParent: view, propertyInParent: 'viewFactory' }
    ),
  );
  if (view.controllers && view.controllers.length) {
    view.controllers.forEach((controller, index) => {
      matches.push(
        ...traverseController(
          classOrFunction,
          controller,
          { ...info, relatedView: view, immediateParent: view.controllers, propertyInParent: index }
        )
      );
    });
  }
  if (view.children && view.children.length) {
    view.children.forEach((viewSlot, index) => {
      matches.push(
        ...traverseViewSlot(
          classOrFunction,
          viewSlot,
          { ...info, childOfViewSlot: viewSlot, relatedView: view, immediateParent: view.children, propertyInParent: index }
        )
      );
    });
  }
  return matches;
}

export function traverseOverrideContext(classOrFunction: any, overrideContext: any, info: TraversalInfo) {
  const matches = [] as Array<TraversalInfo>;
  if (!overrideContext || info.previouslyTraversed.has(overrideContext)) return matches;
  info.previouslyTraversed.add(overrideContext);

  matches.push(
    ...traverseViewModel(
      classOrFunction,
      overrideContext.bindingContext,
      { ...info, immediateParent: overrideContext, propertyInParent: 'bindingContext' }
    ),
    ...traverseOverrideContext(
      classOrFunction,
      overrideContext.parentOverrideContext,
      { ...info, immediateParent: overrideContext, propertyInParent: 'parentOverrideContext' }
    ),
  );
  return matches;
}

export function traverseViewSlot(classOrFunction: any, viewSlot: ViewSlotCorrect, info: TraversalInfo) {
  const matches = [] as Array<TraversalInfo>;
  if (!viewSlot || info.previouslyTraversed.has(viewSlot)) return matches;
  info.previouslyTraversed.add(viewSlot);

  matches.push(
    ...traverseViewModel(
      classOrFunction,
      viewSlot.bindingContext,
      { ...info, immediateParent: viewSlot, propertyInParent: 'bindingContext' }
    ),
    ...traverseOverrideContext(
      classOrFunction,
      viewSlot.overrideContext,
      { ...info, immediateParent: viewSlot, propertyInParent: 'overrideContext' }
    ),
  );

  if (viewSlot.children && viewSlot.children.length) {
    viewSlot.children.forEach((child, index) => {
      matches.push(
        ...traverseView(
          classOrFunction,
          child,
          { ...info, childOfViewSlot: viewSlot, relatedView: child, immediateParent: viewSlot.children, propertyInParent: index }
        ),
      );
    });
  }

  return matches;
}