#import "FilamentMethodCallHandler.h"
#import "FilamentViewController.h"
#import "FilamentNativeViewFactory.h"

static const FilamentMethodCallHandler* _handler;

static polyvox::ResourceBuffer loadResourceGlobal(const char* name) {
  return [_handler loadResource:name];
}

static void* freeResourceGlobal(void* mem, size_t size, void* misc) {
  [_handler freeResource:mem size:size misc:misc ];
  return nullptr;
}

@implementation FilamentMethodCallHandler {
  FilamentViewController *_controller;
  FlutterMethodChannel* _channel;
  polyvox::FilamentViewer* _viewer;
  void* _layer;
  
  NSObject<FlutterPluginRegistrar>* _registrar;
}
- (instancetype)initWithController:(FilamentViewController*)controller
                         registrar:(NSObject<FlutterPluginRegistrar>*)registrar
                         viewId:(int64_t)viewId
                         layer:(void*)layer
{
  _layer = layer;
  _registrar = registrar;
  _controller = controller;
  NSString* channelName = [NSString stringWithFormat:@"%@_%d",VIEW_TYPE,viewId];
  _channel = [FlutterMethodChannel
    methodChannelWithName:channelName
          binaryMessenger:[registrar messenger]];
  [_channel setMethodCallHandler:^(FlutterMethodCall * _Nonnull call, FlutterResult  _Nonnull result) {
    [self handleMethodCall:call result:result];
  }];
  _handler = self;
  return self;
}

- (void)handleMethodCall:(FlutterMethodCall* _Nonnull)call result:(FlutterResult _Nonnull )result {
  if([@"initialize" isEqualToString:call.method]) {
      if(!call.arguments)
        _viewer = new polyvox::FilamentViewer(_layer, nullptr, nullptr, loadResourceGlobal, freeResourceGlobal);
      else
        _viewer = new polyvox::FilamentViewer(_layer, [call.arguments[0] UTF8String], [call.arguments[1] UTF8String], loadResourceGlobal, freeResourceGlobal);
      [_controller setViewer:_viewer];
      [_controller startDisplayLink];
      result(@"OK");
  } else if([@"loadSkybox" isEqualToString:call.method]) {
    if(!_viewer)
      return;

    _viewer->loadSkybox([call.arguments[0] UTF8String], [call.arguments[1] UTF8String]);
    result(@"OK");
  } else if([@"loadGlb" isEqualToString:call.method]) {
    if(!_viewer)
      return; // TODO should throw exception here
    _viewer->loadGlb([call.arguments UTF8String]);
    result(@"OK");
  } else if([@"loadGltf" isEqualToString:call.method]) {
    if(!_viewer)
      return; // TODO should throw exception here
    _viewer->loadGltf([call.arguments[0] UTF8String], [call.arguments[1] UTF8String]);
    result(@"OK");
  } else if([@"panStart" isEqualToString:call.method]) {
    if(!_viewer)
      return;
    _viewer->manipulator->grabBegin([call.arguments[0] intValue], [call.arguments[1] intValue], true);
    result(@"OK");
  } else if([@"panUpdate" isEqualToString:call.method]) {
    if(!_viewer)
      return;
    _viewer->manipulator->grabUpdate([call.arguments[0] intValue], [call.arguments[1] intValue]);
    result(@"OK");
  } else if([@"panEnd" isEqualToString:call.method]) {
    if(!_viewer)
      return;
    _viewer->manipulator->grabEnd();
    result(@"OK");
  } else if([@"rotateStart" isEqualToString:call.method]) {
    if(!_viewer)
      return;
    _viewer->manipulator->grabBegin([call.arguments[0] intValue], [call.arguments[1] intValue], false);
    result(@"OK");
  } else if([@"rotateUpdate" isEqualToString:call.method]) {
    if(!_viewer)
      return;
    _viewer->manipulator->grabUpdate([call.arguments[0] intValue], [call.arguments[1] intValue]);
    result(@"OK");
  } else if([@"rotateEnd" isEqualToString:call.method]) {
    if(!_viewer)
      return;
    _viewer->manipulator->grabEnd();
    result(@"OK");
  } else if([@"releaseSourceAssets" isEqualToString:call.method]) {
    _viewer->releaseSourceAssets();
    result(@"OK");
  } else if([@"animateWeights" isEqualToString:call.method]) {
    NSArray* frameData = call.arguments[0];
    NSNumber* numWeights = call.arguments[1];
    NSNumber* frameRate = call.arguments[2];

    float* framesArr = (float*)malloc([frameData count] *sizeof(float));
    for(int i =0 ; i < [frameData count]; i++) {
      *(framesArr+i) = [[frameData objectAtIndex:i] floatValue];
    }
    _viewer->animateWeights((float*)framesArr, [numWeights intValue], [frameData count], [frameRate floatValue]);
    result(@"OK");
  } else if([@"createMorpher" isEqualToString:call.method]) {
    const char* meshName = [call.arguments[0] UTF8String];
    NSArray* primitiveIndices = call.arguments[1];
    int* primitiveIndicesArr = (int*)malloc([primitiveIndices count] *sizeof(int));
    for(int i =0 ; i < [primitiveIndices count]; i++) {
      primitiveIndicesArr[i] = [[primitiveIndices objectAtIndex:i] intValue];
    }
    _viewer->createMorpher(meshName, primitiveIndicesArr, [primitiveIndices count]);
    free(primitiveIndicesArr);
    result(@"OK");
  } else if([@"playAnimation" isEqualToString:call.method]) {
    _viewer->playAnimation([call.arguments intValue]);
    result(@"OK");
  } else if([@"getTargetNames" isEqualToString:call.method]) {
    polyvox::StringList list = _viewer->getTargetNames([call.arguments UTF8String]);
    NSMutableArray* asArray = [NSMutableArray arrayWithCapacity:list.count];
    for(int i = 0; i < list.count; i++) {
      asArray[i] = [NSString stringWithFormat:@"%s", list.strings[i]];
    }
    result(asArray);
  } else if([@"applyWeights" isEqualToString:call.method]) {
    if(!_viewer)
      return;
    NSArray* nWeights = call.arguments;
    
    int count = [nWeights count];
    float weights[count];
    for(int i=0; i < count; i++) {
      weights[i] = [nWeights[i] floatValue];
    }
    _viewer->applyWeights(weights, count);
    result(@"OK");
  } else if([@"zoom" isEqualToString:call.method]) {
    if(!_viewer)
      return;
    _viewer->manipulator->scroll(0.0f, 0.0f, [call.arguments floatValue]);
    result(@"OK");
  } else {
    
    result(FlutterMethodNotImplemented);
  }
}

- (polyvox::ResourceBuffer)loadResource:(const char* const)path {
    NSString* p = [NSString stringWithFormat:@"%s", path];
    NSString* key = [_registrar lookupKeyForAsset:p];
    NSString* nsPath = [[NSBundle mainBundle] pathForResource:key
                                                      ofType:nil];
    if (![[NSFileManager defaultManager] fileExistsAtPath:nsPath]) {
        NSLog(@"Error: no file exists at %@", p);
        exit(-1);
    }

    NSData* buffer = [NSData dataWithContentsOfFile:nsPath];
    void* cpy = malloc([buffer length]);
    memcpy(cpy, [buffer bytes],  [buffer length]); // can we avoid this copy somehow?
    polyvox::ResourceBuffer rbuf(cpy, [buffer length]);
    return rbuf;
}

- (void)freeResource:(void*)mem size:(size_t)s misc:(void *)m {
    free(mem);
}

- (void)ready {
  [_channel invokeMethod:@"ready" arguments:nil];
}

@end