/* -LICENSE-START-
** Copyright (c) 2009 Blackmagic Design
**
** Permission is hereby granted, free of charge, to any person or organization
** obtaining a copy of the software and accompanying documentation covered by
** this license (the "Software") to use, reproduce, display, distribute,
** execute, and transmit the Software, and to prepare derivative works of the
** Software, and to permit third-parties to whom the Software is furnished to
** do so, all subject to the following:
**
** The copyright notices in the Software and this entire statement, including
** the above license grant, this restriction and the following disclaimer,
** must be included in all copies of the Software, in whole or in part, and
** all derivative works of the Software, unless such copies or derivative
** works are solely in the form of machine-executable object code generated by
** a source language processor.
**
** THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
** IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
** FITNESS FOR A PARTICULAR PURPOSE, TITLE AND NON-INFRINGEMENT. IN NO EVENT
** SHALL THE COPYRIGHT HOLDERS OR ANYONE DISTRIBUTING THE SOFTWARE BE LIABLE
** FOR ANY DAMAGES OR OTHER LIABILITY, WHETHER IN CONTRACT, TORT OR OTHERWISE,
** ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
** DEALINGS IN THE SOFTWARE.
** -LICENSE-END-
**/

#include <stdio.h>
#include <pthread.h>
#include <dlfcn.h>

#include "DeckLinkAPI.h"

#define kDeckLinkAPI_Name "libDeckLinkAPI.so"
#define KDeckLinkPreviewAPI_Name "libDeckLinkPreviewAPI.so"

typedef IDeckLinkIterator* (*CreateIteratorFunc)(void);
typedef IDeckLinkAPIInformation* (*CreateAPIInformationFunc)(void);
typedef IDeckLinkGLScreenPreviewHelper* (*CreateOpenGLScreenPreviewHelperFunc)(void);
typedef IDeckLinkVideoConversion* (*CreateVideoConversionInstanceFunc)(void);
typedef IDeckLinkDiscovery* (*CreateDeckLinkDiscoveryInstanceFunc)(void);

static pthread_once_t gDeckLinkOnceControl = PTHREAD_ONCE_INIT;
static pthread_once_t gPreviewOnceControl = PTHREAD_ONCE_INIT;

static bool gLoadedDeckLinkAPI = false;

static CreateIteratorFunc gCreateIteratorFunc = NULL;
static CreateAPIInformationFunc gCreateAPIInformationFunc = NULL;
static CreateOpenGLScreenPreviewHelperFunc gCreateOpenGLPreviewFunc = NULL;
static CreateVideoConversionInstanceFunc gCreateVideoConversionFunc = NULL;
static CreateDeckLinkDiscoveryInstanceFunc gCreateDeckLinkDiscoveryFunc = NULL;

void InitDeckLinkAPI(void) {
  void* libraryHandle;

  libraryHandle = dlopen(kDeckLinkAPI_Name, RTLD_NOW | RTLD_GLOBAL);
  if (!libraryHandle) {
    fprintf(stderr, "%s\n", dlerror());
    return;
  }

  gLoadedDeckLinkAPI = true;

  gCreateIteratorFunc = (CreateIteratorFunc)dlsym(libraryHandle, "CreateDeckLinkIteratorInstance_0002");
  if (!gCreateIteratorFunc) fprintf(stderr, "%s\n", dlerror());
  gCreateAPIInformationFunc =
      (CreateAPIInformationFunc)dlsym(libraryHandle, "CreateDeckLinkAPIInformationInstance_0001");
  if (!gCreateAPIInformationFunc) fprintf(stderr, "%s\n", dlerror());
  gCreateVideoConversionFunc =
      (CreateVideoConversionInstanceFunc)dlsym(libraryHandle, "CreateVideoConversionInstance_0001");
  if (!gCreateVideoConversionFunc) fprintf(stderr, "%s\n", dlerror());
  gCreateDeckLinkDiscoveryFunc =
      (CreateDeckLinkDiscoveryInstanceFunc)dlsym(libraryHandle, "CreateDeckLinkDiscoveryInstance_0001");
  if (!gCreateDeckLinkDiscoveryFunc) fprintf(stderr, "%s\n", dlerror());
}

void InitDeckLinkPreviewAPI(void) {
  void* libraryHandle;

  libraryHandle = dlopen(KDeckLinkPreviewAPI_Name, RTLD_NOW | RTLD_GLOBAL);
  if (!libraryHandle) {
    fprintf(stderr, "%s\n", dlerror());
    return;
  }
  gCreateOpenGLPreviewFunc =
      (CreateOpenGLScreenPreviewHelperFunc)dlsym(libraryHandle, "CreateOpenGLScreenPreviewHelper_0001");
  if (!gCreateOpenGLPreviewFunc) fprintf(stderr, "%s\n", dlerror());
}

bool IsDeckLinkAPIPresent(void) {
  // If the DeckLink API dynamic library was successfully loaded, return this knowledge to the caller
  return gLoadedDeckLinkAPI;
}

IDeckLinkIterator* CreateDeckLinkIteratorInstance(void) {
  pthread_once(&gDeckLinkOnceControl, InitDeckLinkAPI);

  if (gCreateIteratorFunc == NULL) return NULL;
  return gCreateIteratorFunc();
}

IDeckLinkAPIInformation* CreateDeckLinkAPIInformationInstance(void) {
  pthread_once(&gDeckLinkOnceControl, InitDeckLinkAPI);

  if (gCreateAPIInformationFunc == NULL) return NULL;
  return gCreateAPIInformationFunc();
}

IDeckLinkGLScreenPreviewHelper* CreateOpenGLScreenPreviewHelper(void) {
  pthread_once(&gDeckLinkOnceControl, InitDeckLinkAPI);
  pthread_once(&gPreviewOnceControl, InitDeckLinkPreviewAPI);

  if (gCreateOpenGLPreviewFunc == NULL) return NULL;
  return gCreateOpenGLPreviewFunc();
}

IDeckLinkVideoConversion* CreateVideoConversionInstance(void) {
  pthread_once(&gDeckLinkOnceControl, InitDeckLinkAPI);

  if (gCreateVideoConversionFunc == NULL) return NULL;
  return gCreateVideoConversionFunc();
}

IDeckLinkDiscovery* CreateDeckLinkDiscoveryInstance(void) {
  pthread_once(&gDeckLinkOnceControl, InitDeckLinkAPI);

  if (gCreateDeckLinkDiscoveryFunc == NULL) return NULL;
  return gCreateDeckLinkDiscoveryFunc();
}
