// Copyright (c) 2011 The Chromium Embedded Framework Authors.
// Portions copyright (c) 2006-2008 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "osrplugin.h"
#include "cefclient.h"
#include "string_util.h"
#include <gl/gl.h>
#include <gl/glu.h>
#define _USE_MATH_DEFINES
#include <math.h>
#include <sstream>

#ifdef _WIN32

// Initialized in NP_Initialize.
NPNetscapeFuncs* g_osrbrowser = NULL;

namespace {

GLuint g_textureID = -1;
float g_spinX = 0.0f;
float g_spinY = 0.0f;
int g_width = -1, g_height = -1;
CefRefPtr<CefBrowser> g_offscreenBrowser;

// Class holding pointers for the client plugin window.
class ClientPlugin
{
public:
  ClientPlugin()
  {
    hWnd = NULL;
    hDC = NULL;
    hRC = NULL;
  }

  HWND hWnd;
  HDC hDC;
  HGLRC hRC;
};

// Handler for off-screen rendering windows.
class ClientOSRHandler : public ClientHandler
{
public:
  ClientOSRHandler(ClientPlugin* plugin)
    : plugin_(plugin), view_buffer_(NULL), view_buffer_size_(0),
      popup_buffer_(NULL), popup_buffer_size_(0)
  {
  }
  virtual ~ClientOSRHandler()
  {
    if (view_buffer_)
      delete [] view_buffer_;
    if (popup_buffer_)
      delete [] popup_buffer_;
  }

  virtual RetVal HandleBeforeCreated(CefRefPtr<CefBrowser> parentBrowser,
                                     CefWindowInfo& createInfo, bool popup,
                                     const CefPopupFeatures& popupFeatures,
                                     CefRefPtr<CefHandler>& handler,
                                     const CefString& url,
                                     CefBrowserSettings& settings)
  {
    REQUIRE_UI_THREAD();

    // Popups will be redirected to this browser window.
    if(popup) {
      createInfo.m_bWindowRenderingDisabled = TRUE;
      handler = new ClientPopupHandler(g_offscreenBrowser);
    }

    return RV_CONTINUE;
  }

  virtual RetVal HandleAfterCreated(CefRefPtr<CefBrowser> browser)
  {
    REQUIRE_UI_THREAD();

    // Set the view size to match the plugin window size.
    browser->SetSize(PET_VIEW, g_width, g_height);

    g_offscreenBrowser = browser;

    return ClientHandler::HandleAfterCreated(browser);
  }

  virtual RetVal HandleAddressChange(CefRefPtr<CefBrowser> browser,
                                     CefRefPtr<CefFrame> frame,
                                     const CefString& url)
  {
    REQUIRE_UI_THREAD();

    // Set the "url" value in the HTML.
    std::stringstream ss;
    std::string urlStr = url;
    StringReplace(urlStr, "'", "\\'");
    ss << "document.getElementById('url').value = '" << urlStr.c_str() << "'";
    AppGetBrowser()->GetMainFrame()->ExecuteJavaScript(ss.str(), "", 0);
    return RV_CONTINUE;
  }

  virtual RetVal HandleTitleChange(CefRefPtr<CefBrowser> browser,
                                   const CefString& title)
  {
    REQUIRE_UI_THREAD();

    // Set the "title" value in the HTML.
    std::stringstream ss;
    std::string titleStr = title;
    StringReplace(titleStr, "'", "\\'");
    ss << "document.getElementById('title').innerHTML = '" <<
        titleStr.c_str() << "'";
    AppGetBrowser()->GetMainFrame()->ExecuteJavaScript(ss.str(), "", 0);
    return RV_CONTINUE;
  }

  virtual RetVal HandleGetRect(CefRefPtr<CefBrowser> browser, bool screen,
                               CefRect& rect)
  {
    REQUIRE_UI_THREAD();

    // The simulated screen and view rectangle are the same. This is necessary
    // for popup menus to be located and sized inside the view.
    rect.x = rect.y = 0;
    rect.width = g_width;
    rect.height = g_height;
    return RV_CONTINUE;
  }
  
  virtual RetVal HandleGetScreenPoint(CefRefPtr<CefBrowser> browser,
                                      int viewX, int viewY, int& screenX,
                                      int& screenY)
  {
    REQUIRE_UI_THREAD();

    // Convert the point from view coordinates to actual screen coordinates.
    POINT screen_pt = {viewX, viewY};
    MapWindowPoints(plugin_->hWnd, HWND_DESKTOP, &screen_pt, 1);
    screenX = screen_pt.x;
    screenY = screen_pt.y;
    return RV_CONTINUE;
  }

  virtual RetVal HandlePopupChange(CefRefPtr<CefBrowser> browser, bool show,
                                   const CefRect& rect)
  {
    REQUIRE_UI_THREAD();

    if (show && rect.width > 0) {
      // Update the popup rectange. It will always be inside the view due to
      // HandleGetRect().
      ASSERT(rect.x + rect.width < g_width &&
             rect.y + rect.height < g_height);
      popup_rect_ = rect;
    } else if(!show) {
      // Clear the popup buffer.
      popup_rect_.Set(0,0,0,0);
      if (popup_buffer_) {
        delete [] popup_buffer_;
        popup_buffer_ = NULL;
        popup_buffer_size_ = 0;
      }
    }
    return RV_CONTINUE;
  }

  virtual RetVal HandlePaint(CefRefPtr<CefBrowser> browser,
                             PaintElementType type, const CefRect& dirtyRect,
                             const void* buffer)
  {
    REQUIRE_UI_THREAD();

    wglMakeCurrent(plugin_->hDC, plugin_->hRC);
    
    glBindTexture(GL_TEXTURE_2D, g_textureID);
    
    if (type == PET_VIEW) {
      // Paint the view.
      SetRGB(buffer, g_width, g_height, true);

      // Update the whole texture. This is done for simplicity instead of
      // updating just the dirty region.
      glTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, g_width, g_height, GL_RGB,
          GL_UNSIGNED_BYTE, view_buffer_);
    }
    
    if(popup_rect_.width > 0) {
      if (type == PET_POPUP) {
        // Paint the popup.
        SetRGB(buffer, popup_rect_.width, popup_rect_.height, false);
      }

      if (popup_buffer_) {
        // Update the popup region.
        glTexSubImage2D(GL_TEXTURE_2D, 0, popup_rect_.x,
            g_height-popup_rect_.y-popup_rect_.height, popup_rect_.width,
            popup_rect_.height, GL_RGB, GL_UNSIGNED_BYTE, popup_buffer_);
      }
    }

    return RV_CONTINUE;
  }

  virtual RetVal HandleCursorChange(CefRefPtr<CefBrowser> browser,
                                    CefCursorHandle cursor)
  {
    REQUIRE_UI_THREAD();

    // Change the plugin window's cursor.
    SetClassLong(plugin_->hWnd, GCL_HCURSOR,
        static_cast<LONG>(reinterpret_cast<LONG_PTR>(cursor)));
    SetCursor(cursor);
    return RV_CONTINUE;
  }

protected:
  virtual void SetLoading(bool isLoading)
  {
    // Set the "stop" and "reload" button state in the HTML.
    std::stringstream ss;
    ss << "document.getElementById('stop').disabled = "
       << (isLoading?"false":"true") << ";"
       << "document.getElementById('reload').disabled = "
       << (isLoading?"true":"false") << ";";
    AppGetBrowser()->GetMainFrame()->ExecuteJavaScript(ss.str(), "", 0);
  }

  virtual void SetNavState(bool canGoBack, bool canGoForward)
  {
    // Set the "back" and "forward" button state in the HTML.
    std::stringstream ss;
    ss << "document.getElementById('back').disabled = "
       << (canGoBack?"false":"true") << ";";
    ss << "document.getElementById('forward').disabled = "
       << (canGoForward?"false":"true") << ";";
    AppGetBrowser()->GetMainFrame()->ExecuteJavaScript(ss.str(), "", 0);
  }

  // Set the contents of the RGB buffer.
  void SetRGB(const void* src, int width, int height, bool view)
  {
    SetBufferSize(width, height, view);
    ConvertToRGB((unsigned char*)src, view?view_buffer_:popup_buffer_, width,
        height);
  }

  // Size the RGB buffer.
  void SetBufferSize(int width, int height, bool view)
  {
    int dst_size = width * height * 3;
      
    // Allocate a new buffer if necesary.
    if (view) {
      if (dst_size > view_buffer_size_) {
        if (view_buffer_)
          delete [] view_buffer_;
        view_buffer_ = new unsigned char[dst_size];
        view_buffer_size_ = dst_size;
      }
    } else {
      if (dst_size > popup_buffer_size_) {
        if (popup_buffer_)
          delete [] popup_buffer_;
        popup_buffer_ = new unsigned char[dst_size];
        popup_buffer_size_ = dst_size;
      }
    }
  }

  // Convert from BGRA to RGB format and from upper-left to lower-left origin.
  static void ConvertToRGB(const unsigned char* src, unsigned char* dst,
                           int width, int height)
  {
    int sp = 0, dp = (height-1) * width * 3;
    for(int i = 0; i < height; i++) {
      for(int j = 0; j < width; j++, dp += 3, sp += 4) {
        dst[dp] = src[sp+2]; // R
        dst[dp+1] = src[sp+1]; // G
        dst[dp+2] = src[sp]; // B
      }
      dp -= width * 6;
    }
  }

private:
  ClientPlugin* plugin_;
  unsigned char* view_buffer_;
  int view_buffer_size_;
  unsigned char* popup_buffer_;
  int popup_buffer_size_;
  CefRect popup_rect_;
};

// Forward declarations of functions included in this code module:
LRESULT CALLBACK PluginWndProc(HWND hWnd, UINT message, WPARAM wParam,
                               LPARAM lParam);

// Enable GL.
void EnableGL(HWND hWnd, HDC * hDC, HGLRC * hRC)
{
  PIXELFORMATDESCRIPTOR pfd;
  int format;
  
  // Get the device context.
  *hDC = GetDC(hWnd);
  
  // Set the pixel format for the DC.
  ZeroMemory(&pfd, sizeof(pfd));
  pfd.nSize = sizeof(pfd);
  pfd.nVersion = 1;
  pfd.dwFlags = PFD_DRAW_TO_WINDOW | PFD_SUPPORT_OPENGL | PFD_DOUBLEBUFFER;
  pfd.iPixelType = PFD_TYPE_RGBA;
  pfd.cColorBits = 24;
  pfd.cDepthBits = 16;
  pfd.iLayerType = PFD_MAIN_PLANE;
  format = ChoosePixelFormat(*hDC, &pfd);
  SetPixelFormat(*hDC, format, &pfd);
  
  // Create and enable the render context.
  *hRC = wglCreateContext(*hDC);
  wglMakeCurrent(*hDC, *hRC);

  glClearColor(0.0f, 0.0f, 0.0f, 1.0f);
  glEnable(GL_TEXTURE_2D);

  // Necessary for non-power-of-2 textures to render correctly.
  glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
}

// Disable GL.
void DisableGL(HWND hWnd, HDC hDC, HGLRC hRC)
{
  // Delete the texture.
  if(g_textureID != -1)
    glDeleteTextures(1, &g_textureID);
  
  wglMakeCurrent(NULL, NULL);
  wglDeleteContext(hRC);
  ReleaseDC(hWnd, hDC);
}

// Size the GL view.
void SizeGL(ClientPlugin* plugin, int width, int height)
{
  g_width = width;
  g_height = height;

  wglMakeCurrent(plugin->hDC, plugin->hRC);

  // Match GL units to screen coordinates.
  glViewport(0, 0, width, height);
  glMatrixMode(GL_PROJECTION);
  glLoadIdentity();
  glOrtho(0, 0, width, height, 0.1, 100.0);

  // Delete the existing exture.
  if(g_textureID != -1)
    glDeleteTextures(1, &g_textureID);

  // Create a new texture.
  glGenTextures(1, &g_textureID);
  glBindTexture(GL_TEXTURE_2D, g_textureID);
  glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
  glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);

  // Start with all white contents.
  int size = width * height * 3;
  unsigned char* buffer = new unsigned char[size];
  memset(buffer, 255, size);
  
  glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, width, height, 0,
      GL_RGB, GL_UNSIGNED_BYTE, buffer);

  delete [] buffer;
  
  if(g_offscreenBrowser.get())
    g_offscreenBrowser->SetSize(PET_VIEW, width, height);
}

// Render the view contents.
void RenderGL(ClientPlugin* plugin)
{
  wglMakeCurrent(plugin->hDC, plugin->hRC);
  
  struct {
    float tu, tv;
    float x, y, z;
  } static vertices[] = {
    {0.0f, 0.0f, -1.0f, -1.0f, 0.0f},
    {1.0f, 0.0f,  1.0f, -1.0f, 0.0f},
    {1.0f, 1.0f,  1.0f,  1.0f, 0.0f},
    {0.0f, 1.0f, -1.0f,  1.0f, 0.0f}
  };

  glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);

  glMatrixMode(GL_MODELVIEW);
  glLoadIdentity();
  //glTranslatef(0.0f, 0.0f, -3.0f);
  
  // Rotate the view based on the mouse spin.
  glRotatef(-g_spinX, 1.0f, 0.0f, 0.0f);
  glRotatef(-g_spinY, 0.0f, 1.0f, 0.0f);

  // Enable alpha blending.
  //glEnable(GL_BLEND);
  //glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);

  // Draw the facets with the texture.
  glBindTexture(GL_TEXTURE_2D, g_textureID);
  glInterleavedArrays(GL_T2F_V3F, 0, vertices);
  glDrawArrays(GL_QUADS, 0, 4);

  //glDisable(GL_BLEND);

  SwapBuffers(plugin->hDC);
}

NPError NPP_NewImpl(NPMIMEType plugin_type, NPP instance, uint16 mode,
                    int16 argc, char* argn[], char* argv[],
                    NPSavedData* saved) {
  if (instance == NULL)
    return NPERR_INVALID_INSTANCE_ERROR;

  ClientPlugin *plugin = new ClientPlugin;
  instance->pdata = reinterpret_cast<void*>(plugin);

  return NPERR_NO_ERROR;
}

NPError NPP_DestroyImpl(NPP instance, NPSavedData** save) {
  ClientPlugin *plugin = reinterpret_cast<ClientPlugin*>(instance->pdata);
  
  if (plugin) {
    if(plugin->hWnd) {
      DestroyWindow(plugin->hWnd);
      DisableGL(plugin->hWnd, plugin->hDC, plugin->hRC);
    }
    delete plugin;
  }

  return NPERR_NO_ERROR;
}

NPError NPP_SetWindowImpl(NPP instance, NPWindow* window_info) {
  if (instance == NULL)
    return NPERR_INVALID_INSTANCE_ERROR;

  if (window_info == NULL)
    return NPERR_GENERIC_ERROR;

  ClientPlugin *plugin = reinterpret_cast<ClientPlugin*>(instance->pdata);
  HWND parent_hwnd = reinterpret_cast<HWND>(window_info->window);
  
  if (plugin->hWnd == NULL)
  {
    WNDCLASS wc;
    HINSTANCE hInstance = GetModuleHandle(NULL);
    
    // Register the window class.
    wc.style = CS_OWNDC;
    wc.lpfnWndProc = PluginWndProc;
    wc.cbClsExtra = 0;
    wc.cbWndExtra = 0;
    wc.hInstance = hInstance;
    wc.hIcon = LoadIcon(NULL, IDI_APPLICATION);
    wc.hCursor = LoadCursor(NULL, IDC_ARROW);
    wc.hbrBackground = (HBRUSH)GetStockObject(WHITE_BRUSH);
    wc.lpszMenuName = NULL;
    wc.lpszClassName = L"ClientOSRPlugin";
    RegisterClass(&wc);
  
    // Create the main window.
    plugin->hWnd = CreateWindow(L"ClientOSRPlugin", L"Client OSR Plugin",
        WS_CHILD|WS_CLIPCHILDREN|WS_CLIPSIBLINGS, 0, 0, 0, 0, parent_hwnd, NULL,
        hInstance, NULL);

    SetWindowLongPtr(plugin->hWnd, GWLP_USERDATA,
        reinterpret_cast<LONG_PTR>(plugin));
    
    // Enable GL drawing for the window.
    EnableGL(plugin->hWnd, &(plugin->hDC), &(plugin->hRC));

    // Create the off-screen rendering window.
    CefWindowInfo windowInfo;
    windowInfo.SetAsOffScreen(plugin->hWnd);
    CefBrowser::CreateBrowser(windowInfo, false,
        new ClientOSRHandler(plugin), "http://www.google.com");
  }

  // Position the plugin window and make sure it's visible.
  RECT parent_rect;
  GetClientRect(parent_hwnd, &parent_rect);
  SetWindowPos(plugin->hWnd, NULL, parent_rect.left, parent_rect.top,
      parent_rect.right - parent_rect.left,
      parent_rect.bottom - parent_rect.top, SWP_SHOWWINDOW);

  UpdateWindow(plugin->hWnd);
  ShowWindow(plugin->hWnd, SW_SHOW);

  return NPERR_NO_ERROR;
}

// Plugin window procedure.
LRESULT CALLBACK PluginWndProc(HWND hWnd, UINT message, WPARAM wParam,
                               LPARAM lParam)
{
  static POINT lastMousePos, curMousePos;
  static bool mouseRotation = false;
  static bool mouseTracking = false;

  ClientPlugin* plugin =
      reinterpret_cast<ClientPlugin*>(GetWindowLongPtr(hWnd, GWLP_USERDATA));
  
  switch(message)
  {
  case WM_CREATE:
    // Start the timer that's used for redrawing.
    SetTimer(hWnd, 1, 20, NULL);
    return 0;
    
  case WM_DESTROY:
    // Stop the timer that's used for redrawing.
    KillTimer(hWnd, 1);
    g_offscreenBrowser = NULL;
    return 0;

 case WM_TIMER:
    RenderGL(plugin);
    break;
    
  case WM_LBUTTONDOWN:
  case WM_RBUTTONDOWN:
    SetCapture(hWnd);
    SetFocus(hWnd);
    if (wParam & MK_SHIFT) {
      // Start rotation effect.
      lastMousePos.x = curMousePos.x = LOWORD(lParam);
      lastMousePos.y = curMousePos.y = HIWORD(lParam);
      mouseRotation = true;
    } else {
      if (g_offscreenBrowser.get()) {
        g_offscreenBrowser->SendMouseClickEvent(LOWORD(lParam), HIWORD(lParam),
            (message==WM_LBUTTONDOWN?MBT_LEFT:MBT_RIGHT), false, 1);
      }
    }
    break;

  case WM_LBUTTONUP:
  case WM_RBUTTONUP:
    if (GetCapture() == hWnd)
      ReleaseCapture();
    if (mouseRotation) {
      // End rotation effect.
      mouseRotation = false;
      g_spinX = 0;
      g_spinY = 0;
    } else {
      if (g_offscreenBrowser.get()) {
        g_offscreenBrowser->SendMouseClickEvent(LOWORD(lParam), HIWORD(lParam),
            (message==WM_LBUTTONUP?MBT_LEFT:MBT_RIGHT), true, 1);
      }
    }
    break;

  case WM_MOUSEMOVE:
    if(mouseRotation) {
      // Apply rotation effect.
      curMousePos.x = LOWORD(lParam);
      curMousePos.y = HIWORD(lParam);
      g_spinX -= (curMousePos.x - lastMousePos.x);
      g_spinY -= (curMousePos.y - lastMousePos.y);
      lastMousePos.x = curMousePos.x;
      lastMousePos.y = curMousePos.y;
    } else {
      if (!mouseTracking) {
        // Start tracking mouse leave. Required for the WM_MOUSELEAVE event to
        // be generated.
        TRACKMOUSEEVENT tme;
        tme.cbSize = sizeof(TRACKMOUSEEVENT);
        tme.dwFlags = TME_LEAVE;
        tme.hwndTrack = hWnd;
        TrackMouseEvent(&tme);
        mouseTracking = true;
      }
      if (g_offscreenBrowser.get()) {
        g_offscreenBrowser->SendMouseMoveEvent(LOWORD(lParam), HIWORD(lParam),
            false);
      }
    }
    break;

  case WM_MOUSELEAVE:
    if (mouseTracking) {
      // Stop tracking mouse leave.
      TRACKMOUSEEVENT tme;
      tme.cbSize = sizeof(TRACKMOUSEEVENT);
      tme.dwFlags = TME_LEAVE & TME_CANCEL;
      tme.hwndTrack = hWnd;
      TrackMouseEvent(&tme);
      mouseTracking = false;
    }
    if (g_offscreenBrowser.get())
      g_offscreenBrowser->SendMouseMoveEvent(0, 0, true);
    break;

  case WM_MOUSEWHEEL:
    if (g_offscreenBrowser.get()) {
      g_offscreenBrowser->SendMouseWheelEvent(LOWORD(lParam), HIWORD(lParam),
          GET_WHEEL_DELTA_WPARAM(wParam));
    }
    break;
  
  case WM_SIZE: {
    int width  = LOWORD(lParam); 
    int height = HIWORD(lParam);
    if(width > 0 && height > 0)
      SizeGL(plugin, width, height);
  } break;

  case WM_SETFOCUS:
  case WM_KILLFOCUS:
    if (g_offscreenBrowser.get())
      g_offscreenBrowser->SendFocusEvent(message==WM_SETFOCUS);
    break;

  case WM_CAPTURECHANGED:
  case WM_CANCELMODE:
    if(!mouseRotation) {
      if (g_offscreenBrowser.get())
        g_offscreenBrowser->SendCaptureLostEvent();
    }
    break;

  case WM_KEYDOWN:
  case WM_KEYUP:
  case WM_SYSKEYDOWN:
  case WM_SYSKEYUP:
  case WM_CHAR:
  case WM_SYSCHAR:
  case WM_IME_CHAR:
    if (g_offscreenBrowser.get()) {
      CefBrowser::KeyType type = KT_CHAR;
      bool sysChar = false, imeChar = false;

      if (message == WM_KEYDOWN || message == WM_SYSKEYDOWN)
        type = KT_KEYDOWN;
      else if (message == WM_KEYUP || message == WM_SYSKEYUP)
        type = KT_KEYUP;
      
      if (message == WM_SYSKEYDOWN || message == WM_SYSKEYUP ||
          message == WM_SYSCHAR)
        sysChar = true;

      if (message == WM_IME_CHAR)
        imeChar = true;

       g_offscreenBrowser->SendKeyEvent(type, wParam, lParam, sysChar, imeChar);
    }
    break;

  case WM_PAINT: {
    PAINTSTRUCT ps;
    BeginPaint(hWnd, &ps);
    EndPaint(hWnd, &ps);
  } return 0;

  case WM_ERASEBKGND:
    return 0;
  }

  return DefWindowProc(hWnd, message, wParam, lParam);
}

} // namespace

NPError API_CALL NP_OSRGetEntryPoints(NPPluginFuncs* pFuncs)
{
  pFuncs->newp = NPP_NewImpl;
  pFuncs->destroy = NPP_DestroyImpl;
  pFuncs->setwindow = NPP_SetWindowImpl;
  return NPERR_NO_ERROR;
}

NPError API_CALL NP_OSRInitialize(NPNetscapeFuncs* pFuncs)
{
  g_osrbrowser = pFuncs;
  return NPERR_NO_ERROR;
}

NPError API_CALL NP_OSRShutdown(void)
{
  g_osrbrowser = NULL;
  return NPERR_NO_ERROR;
}

CefRefPtr<CefBrowser> GetOffScreenBrowser()
{
  return g_offscreenBrowser;
}

#endif // _WIN32