gif_parser/types/
plain_text_ext.rs

1use crate::{
2    error::{GifParserError, PlainTextExtIo},
3    read_ext::{ReadExt, ReadSubBlockExt},
4};
5use std::io::Read;
6
7#[derive(Debug)]
8pub struct PlainTextExtension {
9    pub text_grid_left: u16,
10    pub text_grid_top: u16,
11    pub text_grid_width: u16,
12    pub text_grid_height: u16,
13    pub cell_width: u8,
14    pub cell_height: u8,
15    pub text_fg_color_index: u8,
16    pub text_bg_color_index: u8,
17    pub plain_text_data: String,
18}
19
20impl PlainTextExtension {
21    pub(crate) fn from_bytes<T: Read>(reader: &mut T) -> Result<Self, GifParserError> {
22        let data = reader
23            .read_bytes::<13>()
24            .map_err(PlainTextExtIo)
25            .map_err(GifParserError::PlainTextExtIo)?;
26
27        if data[0] != 0x0C {
28            return Err(GifParserError::PlainTextExtInvalidBlockSize);
29        }
30
31        let text = {
32            let data = reader
33                .read_subblock()
34                .map_err(PlainTextExtIo)
35                .map_err(GifParserError::PlainTextExtIo)?;
36            String::from_utf8(data).map_err(GifParserError::PlainTextExtInvalidUtf8)?
37        };
38
39        let text_grid_left = data[1..3].try_into().expect("Valid range for u16");
40        let text_grid_top = data[3..5].try_into().expect("Valid range for u16");
41        let text_grid_width = data[5..7].try_into().expect("Valid range for u16");
42        let text_grid_height = data[7..9].try_into().expect("Valid range for u16");
43
44        Ok(Self {
45            text_grid_left: u16::from_le_bytes(text_grid_left),
46            text_grid_top: u16::from_le_bytes(text_grid_top),
47            text_grid_width: u16::from_le_bytes(text_grid_width),
48            text_grid_height: u16::from_le_bytes(text_grid_height),
49            cell_width: data[9],
50            cell_height: data[10],
51            text_fg_color_index: data[11],
52            text_bg_color_index: data[12],
53            plain_text_data: text,
54        })
55    }
56}
gif_parser/types/plain_text_ext.rs

gif_parser/types/
plain_text_ext.rs
