1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
// Copyright 2022 Kévin Commaille
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

//! Types and traits for attachments.

#[cfg(feature = "image-proc")]
use std::io::{BufRead, Cursor, Seek};
use std::time::Duration;

#[cfg(feature = "image-proc")]
use image::GenericImageView;
#[cfg(feature = "image-proc")]
pub use image::ImageFormat;
use ruma::{
    assign,
    events::{
        room::{
            message::{AudioInfo, FileInfo, FormattedBody, VideoInfo},
            ImageInfo, ThumbnailInfo,
        },
        Mentions,
    },
    OwnedTransactionId, TransactionId, UInt,
};

#[cfg(feature = "image-proc")]
use crate::ImageError;

/// Base metadata about an image.
#[derive(Debug, Clone)]
pub struct BaseImageInfo {
    /// The height of the image in pixels.
    pub height: Option<UInt>,
    /// The width of the image in pixels.
    pub width: Option<UInt>,
    /// The file size of the image in bytes.
    pub size: Option<UInt>,
    /// The [BlurHash](https://blurha.sh/) for this image.
    pub blurhash: Option<String>,
}

/// Base metadata about a video.
#[derive(Debug, Clone)]
pub struct BaseVideoInfo {
    /// The duration of the video.
    pub duration: Option<Duration>,
    /// The height of the video in pixels.
    pub height: Option<UInt>,
    /// The width of the video in pixels.
    pub width: Option<UInt>,
    /// The file size of the video in bytes.
    pub size: Option<UInt>,
    /// The [BlurHash](https://blurha.sh/) for this video.
    pub blurhash: Option<String>,
}

/// Base metadata about an audio clip.
#[derive(Debug, Clone)]
pub struct BaseAudioInfo {
    /// The duration of the audio clip.
    pub duration: Option<Duration>,
    /// The file size of the audio clip in bytes.
    pub size: Option<UInt>,
}

/// Base metadata about a file.
#[derive(Debug, Clone)]
pub struct BaseFileInfo {
    /// The size of the file in bytes.
    pub size: Option<UInt>,
}

/// Types of metadata for an attachment.
#[derive(Debug)]
pub enum AttachmentInfo {
    /// The metadata of an image.
    Image(BaseImageInfo),
    /// The metadata of a video.
    Video(BaseVideoInfo),
    /// The metadata of an audio clip.
    Audio(BaseAudioInfo),
    /// The metadata of a file.
    File(BaseFileInfo),
    /// The metadata of a voice message
    Voice {
        /// The audio info
        audio_info: BaseAudioInfo,
        /// The waveform of the voice message
        waveform: Option<Vec<u16>>,
    },
}

impl From<AttachmentInfo> for ImageInfo {
    fn from(info: AttachmentInfo) -> Self {
        match info {
            AttachmentInfo::Image(info) => assign!(ImageInfo::new(), {
                height: info.height,
                width: info.width,
                size: info.size,
                blurhash: info.blurhash,
            }),
            _ => ImageInfo::new(),
        }
    }
}

impl From<AttachmentInfo> for VideoInfo {
    fn from(info: AttachmentInfo) -> Self {
        match info {
            AttachmentInfo::Video(info) => assign!(VideoInfo::new(), {
                duration: info.duration,
                height: info.height,
                width: info.width,
                size: info.size,
                blurhash: info.blurhash,
            }),
            _ => VideoInfo::new(),
        }
    }
}

impl From<AttachmentInfo> for AudioInfo {
    fn from(info: AttachmentInfo) -> Self {
        match info {
            AttachmentInfo::Audio(info) => assign!(AudioInfo::new(), {
                duration: info.duration,
                size: info.size,
            }),
            AttachmentInfo::Voice { audio_info, .. } => assign!(AudioInfo::new(), {
                duration: audio_info.duration,
                size: audio_info.size,
            }),
            _ => AudioInfo::new(),
        }
    }
}

impl From<AttachmentInfo> for FileInfo {
    fn from(info: AttachmentInfo) -> Self {
        match info {
            AttachmentInfo::File(info) => assign!(FileInfo::new(), {
                size: info.size,
            }),
            _ => FileInfo::new(),
        }
    }
}

#[derive(Debug, Clone)]
/// Base metadata about a thumbnail.
pub struct BaseThumbnailInfo {
    /// The height of the thumbnail in pixels.
    pub height: Option<UInt>,
    /// The width of the thumbnail in pixels.
    pub width: Option<UInt>,
    /// The file size of the thumbnail in bytes.
    pub size: Option<UInt>,
}

impl From<BaseThumbnailInfo> for ThumbnailInfo {
    fn from(info: BaseThumbnailInfo) -> Self {
        assign!(ThumbnailInfo::new(), {
            height: info.height,
            width: info.width,
            size: info.size,
        })
    }
}

/// A thumbnail to upload and send for an attachment.
#[derive(Debug)]
pub struct Thumbnail {
    /// The raw bytes of the thumbnail.
    pub data: Vec<u8>,
    /// The type of the thumbnail, this will be used as the content-type header.
    pub content_type: mime::Mime,
    /// The metadata of the thumbnail.
    pub info: Option<BaseThumbnailInfo>,
}

/// Configuration for sending an attachment.
#[derive(Debug, Default)]
pub struct AttachmentConfig {
    pub(crate) txn_id: Option<OwnedTransactionId>,
    pub(crate) info: Option<AttachmentInfo>,
    pub(crate) thumbnail: Option<Thumbnail>,
    pub(crate) caption: Option<String>,
    pub(crate) formatted_caption: Option<FormattedBody>,
    pub(crate) mentions: Option<Mentions>,
    #[cfg(feature = "image-proc")]
    pub(crate) generate_thumbnail: bool,
    #[cfg(feature = "image-proc")]
    pub(crate) thumbnail_size: Option<(u32, u32)>,
    #[cfg(feature = "image-proc")]
    pub(crate) thumbnail_format: ThumbnailFormat,
}

impl AttachmentConfig {
    /// Create a new default `AttachmentConfig` without providing a thumbnail.
    ///
    /// To provide a thumbnail use [`AttachmentConfig::with_thumbnail()`].
    pub fn new() -> Self {
        Self::default()
    }

    /// Generate the thumbnail to send for this media.
    ///
    /// Uses [`generate_image_thumbnail()`].
    ///
    /// Thumbnails can only be generated for supported image attachments. For
    /// more information, see the [image](https://github.com/image-rs/image)
    /// crate.
    ///
    /// If generating the thumbnail failed, the error will be logged and sending
    /// the attachment will proceed without a thumbnail.
    ///
    /// # Arguments
    ///
    /// * `size` - The size of the thumbnail in pixels as a `(width, height)`
    /// tuple. If set to `None`, defaults to `(800, 600)`.
    ///
    /// * `format` - The image format to use to encode the thumbnail.
    #[cfg(feature = "image-proc")]
    #[must_use]
    pub fn generate_thumbnail(mut self, size: Option<(u32, u32)>, format: ThumbnailFormat) -> Self {
        self.generate_thumbnail = true;
        self.thumbnail_size = size;
        self.thumbnail_format = format;
        self
    }

    /// Create a new default `AttachmentConfig` with a `thumbnail`.
    ///
    /// # Arguments
    ///
    /// * `thumbnail` - The thumbnail of the media. If the `content_type` does
    /// not support it (eg audio clips), it is ignored.
    ///
    /// To generate automatically a thumbnail from an image, use
    /// [`AttachmentConfig::new()`] and
    /// [`AttachmentConfig::generate_thumbnail()`].
    pub fn with_thumbnail(thumbnail: Thumbnail) -> Self {
        Self { thumbnail: Some(thumbnail), ..Default::default() }
    }

    /// Set the transaction ID to send.
    ///
    /// # Arguments
    ///
    /// * `txn_id` - A unique ID that can be attached to a `MessageEvent` held
    /// in its unsigned field as `transaction_id`. If not given, one is created
    /// for the message.
    #[must_use]
    pub fn txn_id(mut self, txn_id: &TransactionId) -> Self {
        self.txn_id = Some(txn_id.to_owned());
        self
    }

    /// Set the media metadata to send.
    ///
    /// # Arguments
    ///
    /// * `info` - The metadata of the media. If the `AttachmentInfo` type
    /// doesn't match the `content_type`, it is ignored.
    #[must_use]
    pub fn info(mut self, info: AttachmentInfo) -> Self {
        self.info = Some(info);
        self
    }

    /// Set the optional caption
    ///
    /// # Arguments
    ///
    /// * `caption` - The optional caption
    pub fn caption(mut self, caption: Option<String>) -> Self {
        self.caption = caption;
        self
    }

    /// Set the optional formatted caption
    ///
    /// # Arguments
    ///
    /// * `formatted_caption` - The optional formatted caption
    pub fn formatted_caption(mut self, formatted_caption: Option<FormattedBody>) -> Self {
        self.formatted_caption = formatted_caption;
        self
    }

    /// Set the mentions of the message.
    ///
    /// # Arguments
    ///
    /// * `mentions` - The mentions of the message
    pub fn mentions(mut self, mentions: Option<Mentions>) -> Self {
        self.mentions = mentions;
        self
    }
}

/// Generate a thumbnail for an image.
///
/// This is a convenience method that uses the
/// [image](https://github.com/image-rs/image) crate.
///
/// # Arguments
/// * `content_type` - The type of the media, this will be used as the
///   content-type header.
///
/// * `reader` - A `Reader` that will be used to fetch the raw bytes of the
///   media.
///
/// * `size` - The size of the thumbnail in pixels as a `(width, height)` tuple.
///   If set to `None`, defaults to `(800, 600)`.
///
/// * `format` - The image format to use to encode the thumbnail.
///
/// # Examples
///
/// ```no_run
/// use std::{io::Cursor, path::PathBuf};
///
/// use matrix_sdk::attachment::{
///     generate_image_thumbnail, AttachmentConfig, Thumbnail, ThumbnailFormat,
/// };
/// use mime;
/// # use matrix_sdk::{Client, ruma::room_id };
/// # use url::Url;
/// #
/// # async {
/// # let homeserver = Url::parse("http://localhost:8080")?;
/// # let mut client = Client::new(homeserver).await?;
/// # let room_id = room_id!("!test:localhost");
/// let path = PathBuf::from("/home/example/my-cat.jpg");
/// let image = tokio::fs::read(path).await?;
///
/// let cursor = Cursor::new(&image);
/// let thumbnail = generate_image_thumbnail(
///     &mime::IMAGE_JPEG,
///     cursor,
///     None,
///     ThumbnailFormat::Original,
/// )?;
/// let config = AttachmentConfig::with_thumbnail(thumbnail);
///
/// if let Some(room) = client.get_room(&room_id) {
///     room.send_attachment(
///         "my_favorite_cat.jpg",
///         &mime::IMAGE_JPEG,
///         image,
///         config,
///     )
///     .await?;
/// }
/// # anyhow::Ok(()) };
/// ```
#[cfg(feature = "image-proc")]
pub fn generate_image_thumbnail<R: BufRead + Seek>(
    content_type: &mime::Mime,
    reader: R,
    size: Option<(u32, u32)>,
    format: ThumbnailFormat,
) -> Result<Thumbnail, ImageError> {
    use std::str::FromStr;

    let Some(image_format) = ImageFormat::from_mime_type(content_type) else {
        return Err(ImageError::FormatNotSupported);
    };

    let image = image::load(reader, image_format)?;
    let (original_width, original_height) = image.dimensions();

    let (width, height) = size.unwrap_or((800, 600));

    // Don't generate a thumbnail if it would be bigger than or equal to the
    // original.
    if height >= original_height && width >= original_width {
        return Err(ImageError::ThumbnailBiggerThanOriginal);
    }

    let thumbnail = image.thumbnail(width, height);
    let (thumbnail_width, thumbnail_height) = thumbnail.dimensions();

    let thumbnail_format = match format {
        ThumbnailFormat::Always(format) => format,
        ThumbnailFormat::Fallback(format) if !image_format.writing_enabled() => format,
        ThumbnailFormat::Fallback(_) | ThumbnailFormat::Original => image_format,
    };

    let mut data: Vec<u8> = vec![];
    thumbnail.write_to(&mut Cursor::new(&mut data), thumbnail_format)?;
    let data_size = data.len() as u32;

    let content_type = mime::Mime::from_str(thumbnail_format.to_mime_type())?;

    let info = BaseThumbnailInfo {
        width: Some(thumbnail_width.into()),
        height: Some(thumbnail_height.into()),
        size: Some(data_size.into()),
    };

    Ok(Thumbnail { data, content_type, info: Some(info) })
}

/// The format to use for encoding the thumbnail.
#[cfg(feature = "image-proc")]
#[derive(Debug, Default, Clone, Copy)]
pub enum ThumbnailFormat {
    /// Always use this format.
    ///
    /// Will always return an error if this format is not writable by the
    /// `image` crate.
    Always(ImageFormat),
    /// Try to use the same format as the original image, and fallback to this
    /// one if the original format is not writable.
    ///
    /// Will return an error if both the original format and this format are not
    /// writable by the `image` crate.
    Fallback(ImageFormat),
    /// Only try to use the format of the original image.
    ///
    /// Will return an error if the original format is not writable by the
    /// `image` crate.
    ///
    /// This is the default.
    #[default]
    Original,
}