/* ----------------------------------------------------------------- */
///
/// GetSize
///
/// <summary>
/// ページサイズを取得します。
/// </summary>
///
/// <remarks>
/// PDFium は回転後のサイズを返しますが、Page オブジェクトでは
/// 回転前の情報として格納します。そのため、場合によって幅と
/// 高さの情報を反転しています。
/// </remarks>
///
/* ----------------------------------------------------------------- */
private SizeF GetPageSize(IntPtr handle, int degree)
{
var w = (float)PdfiumApi.FPDF_GetPageWidth(handle);
var h = (float)PdfiumApi.FPDF_GetPageHeight(handle);
return((degree != 90 && degree != 270) ? new SizeF(w, h) : new SizeF(h, w));
}
/* ----------------------------------------------------------------- */
///
/// GetPageRotation
///
/// <summary>
/// ページの回転角度を取得します。
/// </summary>
///
/* ----------------------------------------------------------------- */
private int GetPageRotation(IntPtr handle)
{
var dest = PdfiumApi.FPDFPage_GetRotation(handle);
return(dest == 1 ? 90 :
dest == 2 ? 180 :
dest == 3 ? 270 : 0);
}
/* ----------------------------------------------------------------- */
///
/// Create
///
/// <summary>
/// Creates a PdfFile object from the specified arguments.
/// </summary>
///
/* ----------------------------------------------------------------- */
private PdfFile Create(string password, bool fullaccess)
{
var dest = IO.GetPdfFile(Source, password);
dest.Count = Invoke(e => PdfiumApi.FPDF_GetPageCount(e));
dest.FullAccess = fullaccess;
return(dest);
}
/* ----------------------------------------------------------------- */
///
/// GetText
///
/// <summary>
/// Gets the metadata corresponding to the specified name.
/// </summary>
///
/* ----------------------------------------------------------------- */
private static string GetText(PdfiumReader core, string name)
{
var size = core.Invoke(e => PdfiumApi.FPDF_GetMetaText(e, name, null, 0));
if (size <= 2)
{
return(string.Empty);
}
var buffer = new byte[size];
core.Invoke(e => PdfiumApi.FPDF_GetMetaText(e, name, buffer, size));
return(Encoding.Unicode.GetString(buffer, 0, (int)(size - 2)));
}
/* ----------------------------------------------------------------- */
///
/// Create
///
/// <summary>
/// Creates a new instance of the Encryption class with the
/// specified arguments.
/// </summary>
///
/// <param name="core">PDFium object.</param>
/// <param name="password">Password</param>
///
/// <returns>Encryption object.</returns>
///
/// <remarks>
/// 現在 FPDF_GetDocPermissions の結果で諸々の判定を行っているが
/// 最終的には OwnerPassword で開いた状態でもオリジナルの
/// Permission を取得する事を目指す。それに伴って、各種操作も
/// 修正する必要がある。
/// </remarks>
///
/* ----------------------------------------------------------------- */
public static Encryption Create(PdfiumReader core, string password)
{
var method = core.Invoke(e => PdfiumApi.FPDF_GetSecurityHandlerRevision(e));
var permission = (uint)core.Invoke(e => PdfiumApi.FPDF_GetDocPermissions(e));
var restrict = permission != 0xfffffffc;
return(method == -1 ?
new Encryption() :
new Encryption
{
Enabled = true,
OwnerPassword = restrict ? string.Empty : password,
OpenWithPassword = restrict,
UserPassword = restrict ? password : string.Empty,
Method = CreateMethod(method),
Permission = new Permission(permission),
});
}
/* ----------------------------------------------------------------- */
///
/// Dispose
///
/// <summary>
/// Releases the unmanaged resources used by the PdfiumReader
/// and optionally releases the managed resources.
/// </summary>
///
/// <param name="disposing">
/// true to release both managed and unmanaged resources;
/// false to release only unmanaged resources.
/// </param>
///
/* ----------------------------------------------------------------- */
private void Dispose(bool disposing)
{
if (_disposed)
{
return;
}
_disposed = true;
lock (_lock)
{
if (_core != IntPtr.Zero)
{
PdfiumApi.FPDF_CloseDocument(_core);
_core = IntPtr.Zero;
}
}
if (disposing)
{
_stream?.Dispose();
}
}
/* ----------------------------------------------------------------- */
///
/// Load
///
/// <summary>
/// Loads the PDF document.
/// </summary>
///
/// <param name="password">Password.</param>
///
/* ----------------------------------------------------------------- */
private void Load(string password)
{
var core = PdfiumApi.FPDF_LoadCustomDocument(
new FileAccess
{
Length = (uint)_stream.Length,
GetBlock = Marshal.GetFunctionPointerForDelegate(_delegate),
Parameter = IntPtr.Zero,
},
password
);
if (core == IntPtr.Zero)
{
throw GetLastError();
}
_core = core;
Encryption = EncryptionFactory.Create(this, password);
File = Create(password, !Encryption.OpenWithPassword);
Pages = new ReadOnlyPageList(this, File);
Metadata = MetadataFactory.Create(this);
}
/* ----------------------------------------------------------------- */
///
/// Render
///
/// <summary>
/// Executes the rendering with the specified arguments.
/// </summary>
///
/* ----------------------------------------------------------------- */
private static void Render(IntPtr core, Graphics dest, Page page,
PointF point, SizeF size, int flags)
{
if (core == IntPtr.Zero)
{
return;
}
var n = 5;
var hp = PdfiumApi.FPDF_LoadPage(core, page.Number - 1, n);
if (hp == IntPtr.Zero)
{
throw new LoadException(LoadStatus.PageError);
}
var hdc = dest.GetHdc();
try
{
PdfiumApi.FPDF_RenderPage(
hdc,
hp,
(int)point.X,
(int)point.Y,
(int)size.Width,
(int)size.Height,
GetRotation(page.Delta),
flags,
n
);
}
finally
{
dest.ReleaseHdc(hdc);
PdfiumApi.FPDF_ClosePage(hp);
}
}
/* ----------------------------------------------------------------- */
///
/// GetPage
///
/// <summary>
/// Page オブジェクトを取得します。
/// </summary>
///
/// <param name="index">
/// 最初のページを "ゼロ" とするインデックス
/// </param>
///
/* ----------------------------------------------------------------- */
private Page GetPage(int index)
{
var page = _core.Invoke(e => PdfiumApi.FPDF_LoadPage(e, index, 5));
if (page == IntPtr.Zero)
{
throw _core.GetLastError();
}
try
{
var degree = GetPageRotation(page);
var size = GetPageSize(page, degree);
return(new Page(
File, // File
index + 1, // Number
size, // Size
new Angle(degree), // Rotation
new PointF(72.0f, 72.0f) // Resolution
));
}
finally { PdfiumApi.FPDF_ClosePage(page); }
}