import throttle from 'lodash.throttle';
import {
  vtkInteractorStyleMPRCrosshairs,
  vtkInteractorStyleMPRWindowLevel,
  vtkInteractorStyleMPRRotate,
  vtkSVGCrosshairsWidget,
} from 'react-vtkjs-viewport';

import setMPRLayout from './utils/setMPRLayout.js';
import setViewportToVTK from './utils/setViewportToVTK.js';
import Constants from 'vtk.js/Sources/Rendering/Core/VolumeMapper/Constants.js';

const { BlendMode } = Constants;

const commandsModule = ({ commandsManager }) => {
  // TODO: Put this somewhere else
  let apis = {};

  async function _getActiveViewportVTKApi(viewports) {
    const {
      numRows,
      numColumns,
      layout,
      viewportSpecificData,
      activeViewportIndex,
    } = viewports;

    const currentData = layout.viewports[activeViewportIndex];
    if (currentData && currentData.plugin === 'vtk') {
      // TODO: I was storing/pulling this from Redux but ran into weird issues
      if (apis[activeViewportIndex]) {
        return apis[activeViewportIndex];
      }
    }

    const displaySet = viewportSpecificData[activeViewportIndex];

    let api;
    if (!api) {
      try {
        api = await setViewportToVTK(
          displaySet,
          activeViewportIndex,
          numRows,
          numColumns,
          layout,
          viewportSpecificData
        );
      } catch (error) {
        throw new Error(error);
      }
    }

    return api;
  }

  function _setView(api, sliceNormal, viewUp) {
    const renderWindow = api.genericRenderWindow.getRenderWindow();
    const istyle = renderWindow.getInteractor().getInteractorStyle();
    istyle.setSliceNormal(...sliceNormal);
    istyle.setViewUp(...viewUp);

    renderWindow.render();
  }

  function getVOIFromCornerstoneViewport() {
    const dom = commandsManager.runCommand('getActiveViewportEnabledElement');
    const cornerstoneElement = cornerstone.getEnabledElement(dom);

    if (cornerstoneElement) {
      const imageId = cornerstoneElement.image.imageId;

      const { modality } = cornerstone.metaData.get(
        'generalSeriesModule',
        imageId
      );

      if (modality !== 'PT') {
        const { windowWidth, windowCenter } = cornerstoneElement.viewport.voi;

        return {
          windowWidth,
          windowCenter,
        };
      }
    }
  }

  function setVOI(voi) {
    const { windowWidth, windowCenter } = voi;
    const lower = windowCenter - windowWidth / 2.0;
    const upper = windowCenter + windowWidth / 2.0;

    const rgbTransferFunction = apis[0].volumes[0]
      .getProperty()
      .getRGBTransferFunction(0);

    rgbTransferFunction.setRange(lower, upper);

    apis.forEach(api => {
      api.updateVOI(windowWidth, windowCenter);
    });
  }

  const actions = {
    axial: async ({ viewports }) => {
      const api = await _getActiveViewportVTKApi(viewports);

      apis[viewports.activeViewportIndex] = api;

      _setView(api, [0, 0, 1], [0, -1, 0]);
    },
    sagittal: async ({ viewports }) => {
      const api = await _getActiveViewportVTKApi(viewports);

      apis[viewports.activeViewportIndex] = api;

      _setView(api, [1, 0, 0], [0, 0, 1]);
    },
    coronal: async ({ viewports }) => {
      const api = await _getActiveViewportVTKApi(viewports);

      apis[viewports.activeViewportIndex] = api;

      _setView(api, [0, 1, 0], [0, 0, 1]);
    },
    enableRotateTool: () => {
      apis.forEach(api => {
        const istyle = vtkInteractorStyleMPRRotate.newInstance();

        api.setInteractorStyle({ istyle });
      });
    },
    enableCrosshairsTool: () => {
      apis.forEach((api, apiIndex) => {
        const istyle = vtkInteractorStyleMPRCrosshairs.newInstance();

        api.setInteractorStyle({
          istyle,
          configuration: { apis, apiIndex },
        });
      });
    },
    enableLevelTool: () => {
      function updateVOI(apis, windowWidth, windowCenter) {
        apis.forEach(api => {
          api.updateVOI(windowWidth, windowCenter);
        });
      }

      const throttledUpdateVOIs = throttle(updateVOI, 16, { trailing: true }); // ~ 60 fps

      const callbacks = {
        setOnLevelsChanged: ({ windowCenter, windowWidth }) => {
          apis.forEach(api => {
            const renderWindow = api.genericRenderWindow.getRenderWindow();

            renderWindow.render();
          });

          throttledUpdateVOIs(apis, windowWidth, windowCenter);
        },
      };

      apis.forEach(api => {
        const istyle = vtkInteractorStyleMPRWindowLevel.newInstance();

        api.setInteractorStyle({ istyle, callbacks });
      });
    },
    setSlabThickness: ({ slabThickness }) => {
      apis.forEach(api => {
        api.setSlabThickness(slabThickness);
      });
    },
    changeSlabThickness: ({ change }) => {
      apis.forEach(api => {
        const slabThickness = Math.max(api.getSlabThickness() + change, 0.1);

        api.setSlabThickness(slabThickness);
      });
    },
    setBlendModeToComposite: () => {
      apis.forEach(api => {
        const renderWindow = api.genericRenderWindow.getRenderWindow();
        const istyle = renderWindow.getInteractor().getInteractorStyle();

        const slabThickness = api.getSlabThickness();

        const mapper = api.volumes[0].getMapper();
        if (mapper.setBlendModeToComposite) {
          mapper.setBlendModeToComposite();
        }

        if (istyle.setSlabThickness) {
          istyle.setSlabThickness(slabThickness);
        }
        renderWindow.render();
      });
    },
    setBlendModeToMaximumIntensity: () => {
      apis.forEach(api => {
        const renderWindow = api.genericRenderWindow.getRenderWindow();
        const mapper = api.volumes[0].getMapper();
        if (mapper.setBlendModeToMaximumIntensity) {
          mapper.setBlendModeToMaximumIntensity();
        }
        renderWindow.render();
      });
    },
    setBlendMode: ({ blendMode }) => {
      apis.forEach(api => {
        const renderWindow = api.genericRenderWindow.getRenderWindow();

        api.volumes[0].getMapper().setBlendMode(blendMode);

        renderWindow.render();
      });
    },
    mpr2d: async ({ viewports }) => {
      // TODO push a lot of this backdoor logic lower down to the library level.
      const displaySet =
        viewports.viewportSpecificData[viewports.activeViewportIndex];

      // Get current VOI if cornerstone viewport.
      const cornerstoneVOI = getVOIFromCornerstoneViewport();

      const viewportProps = [
        {
          //Axial
          orientation: {
            sliceNormal: [0, 0, 1],
            viewUp: [0, -1, 0],
          },
        },
        {
          // Sagital
          orientation: {
            sliceNormal: [1, 0, 0],
            viewUp: [0, 0, 1],
          },
        },
        {
          // Coronal
          orientation: {
            sliceNormal: [0, 1, 0],
            viewUp: [0, 0, 1],
          },
        },
      ];

      try {
        apis = await setMPRLayout(displaySet, viewportProps, 1, 3);
      } catch (error) {
        throw new Error(error);
      }

      if (cornerstoneVOI) {
        setVOI(cornerstoneVOI);
      }

      // Add widgets and set default interactorStyle of each viewport.
      apis.forEach((api, apiIndex) => {
        api.addSVGWidget(
          vtkSVGCrosshairsWidget.newInstance(),
          'crosshairsWidget'
        );

        const istyle = vtkInteractorStyleMPRCrosshairs.newInstance();

        api.setInteractorStyle({
          istyle,
          configuration: { apis, apiIndex },
        });
      });
    },
  };

  window.vtkActions = actions;

  const definitions = {
    axial: {
      commandFn: actions.axial,
      storeContexts: ['viewports'],
      options: {},
    },
    coronal: {
      commandFn: actions.coronal,
      storeContexts: ['viewports'],
      options: {},
    },
    sagittal: {
      commandFn: actions.sagittal,
      storeContexts: ['viewports'],
      options: {},
    },
    enableRotateTool: {
      commandFn: actions.enableRotateTool,
      storeContexts: [],
      options: {},
    },
    enableCrosshairsTool: {
      commandFn: actions.enableCrosshairsTool,
      storeContexts: [],
      options: {},
    },
    enableLevelTool: {
      commandFn: actions.enableLevelTool,
      storeContexts: [],
      options: {},
    },
    setBlendModeToComposite: {
      commandFn: actions.setBlendModeToComposite,
      storeContexts: [],
      options: { blendMode: BlendMode.COMPOSITE_BLEND },
    },
    setBlendModeToMaximumIntensity: {
      commandFn: actions.setBlendModeToMaximumIntensity,
      storeContexts: [],
      options: { blendMode: BlendMode.MAXIMUM_INTENSITY_BLEND },
    },
    setBlendModeToMinimumIntensity: {
      commandFn: actions.setBlendMode,
      storeContexts: [],
      options: { blendMode: BlendMode.MINIMUM_INTENSITY_BLEND },
    },
    setBlendModeToAverageIntensity: {
      commandFn: actions.setBlendMode,
      storeContexts: [],
      options: { blendMode: BlendMode.AVERAGE_INTENSITY_BLEND },
    },
    setSlabThickness: {
      // TODO: How do we pass in a function argument?
      commandFn: actions.setSlabThickness,
      storeContexts: [],
      options: {},
    },
    increaseSlabThickness: {
      commandFn: actions.changeSlabThickness,
      storeContexts: [],
      options: {
        change: 3,
      },
    },
    decreaseSlabThickness: {
      commandFn: actions.changeSlabThickness,
      storeContexts: [],
      options: {
        change: -3,
      },
    },
    mpr2d: {
      commandFn: actions.mpr2d,
      storeContexts: ['viewports'],
      options: {},
      context: 'VIEWER',
    },
  };

  return {
    definitions,
    defaultContext: 'ACTIVE_VIEWPORT::VTK',
  };
};

export default commandsModule;