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Diffstat (limited to 'graphics/src/widget/qr_code.rs')
| -rw-r--r-- | graphics/src/widget/qr_code.rs | 301 |
1 files changed, 0 insertions, 301 deletions
diff --git a/graphics/src/widget/qr_code.rs b/graphics/src/widget/qr_code.rs deleted file mode 100644 index 12ce5b1f..00000000 --- a/graphics/src/widget/qr_code.rs +++ /dev/null @@ -1,301 +0,0 @@ -//! Encode and display information in a QR code. -use crate::renderer::{self, Renderer}; -use crate::widget::canvas; -use crate::Backend; - -use iced_native::layout; -use iced_native::widget::Tree; -use iced_native::{ - Color, Element, Layout, Length, Point, Rectangle, Size, Vector, Widget, -}; -use thiserror::Error; - -const DEFAULT_CELL_SIZE: u16 = 4; -const QUIET_ZONE: usize = 2; - -/// A type of matrix barcode consisting of squares arranged in a grid which -/// can be read by an imaging device, such as a camera. -#[derive(Debug)] -pub struct QRCode<'a> { - state: &'a State, - dark: Color, - light: Color, - cell_size: u16, -} - -impl<'a> QRCode<'a> { - /// Creates a new [`QRCode`] with the provided [`State`]. - pub fn new(state: &'a State) -> Self { - Self { - cell_size: DEFAULT_CELL_SIZE, - dark: Color::BLACK, - light: Color::WHITE, - state, - } - } - - /// Sets both the dark and light [`Color`]s of the [`QRCode`]. - pub fn color(mut self, dark: Color, light: Color) -> Self { - self.dark = dark; - self.light = light; - self - } - - /// Sets the size of the squares of the grid cell of the [`QRCode`]. - pub fn cell_size(mut self, cell_size: u16) -> Self { - self.cell_size = cell_size; - self - } -} - -impl<'a, Message, B, T> Widget<Message, Renderer<B, T>> for QRCode<'a> -where - B: Backend, -{ - fn width(&self) -> Length { - Length::Shrink - } - - fn height(&self) -> Length { - Length::Shrink - } - - fn layout( - &self, - _renderer: &Renderer<B, T>, - _limits: &layout::Limits, - ) -> layout::Node { - let side_length = (self.state.width + 2 * QUIET_ZONE) as f32 - * f32::from(self.cell_size); - - layout::Node::new(Size::new(side_length, side_length)) - } - - fn draw( - &self, - _state: &Tree, - renderer: &mut Renderer<B, T>, - _theme: &T, - _style: &renderer::Style, - layout: Layout<'_>, - _cursor_position: Point, - _viewport: &Rectangle, - ) { - use iced_native::Renderer as _; - - let bounds = layout.bounds(); - let side_length = self.state.width + 2 * QUIET_ZONE; - - // Reuse cache if possible - let geometry = self.state.cache.draw(bounds.size(), |frame| { - // Scale units to cell size - frame.scale(f32::from(self.cell_size)); - - // Draw background - frame.fill_rectangle( - Point::ORIGIN, - Size::new(side_length as f32, side_length as f32), - self.light, - ); - - // Avoid drawing on the quiet zone - frame.translate(Vector::new(QUIET_ZONE as f32, QUIET_ZONE as f32)); - - // Draw contents - self.state - .contents - .iter() - .enumerate() - .filter(|(_, value)| **value == qrcode::Color::Dark) - .for_each(|(index, _)| { - let row = index / self.state.width; - let column = index % self.state.width; - - frame.fill_rectangle( - Point::new(column as f32, row as f32), - Size::UNIT, - self.dark, - ); - }); - }); - - let translation = Vector::new(bounds.x, bounds.y); - - renderer.with_translation(translation, |renderer| { - renderer.draw_primitive(geometry.into_primitive()); - }); - } -} - -impl<'a, Message, B, T> From<QRCode<'a>> - for Element<'a, Message, Renderer<B, T>> -where - B: Backend, -{ - fn from(qr_code: QRCode<'a>) -> Self { - Self::new(qr_code) - } -} - -/// The state of a [`QRCode`]. -/// -/// It stores the data that will be displayed. -#[derive(Debug)] -pub struct State { - contents: Vec<qrcode::Color>, - width: usize, - cache: canvas::Cache, -} - -impl State { - /// Creates a new [`State`] with the provided data. - /// - /// This method uses an [`ErrorCorrection::Medium`] and chooses the smallest - /// size to display the data. - pub fn new(data: impl AsRef<[u8]>) -> Result<Self, Error> { - let encoded = qrcode::QrCode::new(data)?; - - Ok(Self::build(encoded)) - } - - /// Creates a new [`State`] with the provided [`ErrorCorrection`]. - pub fn with_error_correction( - data: impl AsRef<[u8]>, - error_correction: ErrorCorrection, - ) -> Result<Self, Error> { - let encoded = qrcode::QrCode::with_error_correction_level( - data, - error_correction.into(), - )?; - - Ok(Self::build(encoded)) - } - - /// Creates a new [`State`] with the provided [`Version`] and - /// [`ErrorCorrection`]. - pub fn with_version( - data: impl AsRef<[u8]>, - version: Version, - error_correction: ErrorCorrection, - ) -> Result<Self, Error> { - let encoded = qrcode::QrCode::with_version( - data, - version.into(), - error_correction.into(), - )?; - - Ok(Self::build(encoded)) - } - - fn build(encoded: qrcode::QrCode) -> Self { - let width = encoded.width(); - let contents = encoded.into_colors(); - - Self { - contents, - width, - cache: canvas::Cache::new(), - } - } -} - -#[derive(Debug, Clone, Copy, PartialEq, Eq)] -/// The size of a [`QRCode`]. -/// -/// The higher the version the larger the grid of cells, and therefore the more -/// information the [`QRCode`] can carry. -pub enum Version { - /// A normal QR code version. It should be between 1 and 40. - Normal(u8), - - /// A micro QR code version. It should be between 1 and 4. - Micro(u8), -} - -impl From<Version> for qrcode::Version { - fn from(version: Version) -> Self { - match version { - Version::Normal(v) => qrcode::Version::Normal(i16::from(v)), - Version::Micro(v) => qrcode::Version::Micro(i16::from(v)), - } - } -} - -/// The error correction level. -/// -/// It controls the amount of data that can be damaged while still being able -/// to recover the original information. -/// -/// A higher error correction level allows for more corrupted data. -#[derive(Debug, Clone, Copy, PartialEq, Eq)] -pub enum ErrorCorrection { - /// Low error correction. 7% of the data can be restored. - Low, - /// Medium error correction. 15% of the data can be restored. - Medium, - /// Quartile error correction. 25% of the data can be restored. - Quartile, - /// High error correction. 30% of the data can be restored. - High, -} - -impl From<ErrorCorrection> for qrcode::EcLevel { - fn from(ec_level: ErrorCorrection) -> Self { - match ec_level { - ErrorCorrection::Low => qrcode::EcLevel::L, - ErrorCorrection::Medium => qrcode::EcLevel::M, - ErrorCorrection::Quartile => qrcode::EcLevel::Q, - ErrorCorrection::High => qrcode::EcLevel::H, - } - } -} - -/// An error that occurred when building a [`State`] for a [`QRCode`]. -#[derive(Debug, Clone, Copy, PartialEq, Eq, Error)] -pub enum Error { - /// The data is too long to encode in a QR code for the chosen [`Version`]. - #[error( - "The data is too long to encode in a QR code for the chosen version" - )] - DataTooLong, - - /// The chosen [`Version`] and [`ErrorCorrection`] combination is invalid. - #[error( - "The chosen version and error correction level combination is invalid." - )] - InvalidVersion, - - /// One or more characters in the provided data are not supported by the - /// chosen [`Version`]. - #[error( - "One or more characters in the provided data are not supported by the \ - chosen version" - )] - UnsupportedCharacterSet, - - /// The chosen ECI designator is invalid. A valid designator should be - /// between 0 and 999999. - #[error( - "The chosen ECI designator is invalid. A valid designator should be \ - between 0 and 999999." - )] - InvalidEciDesignator, - - /// A character that does not belong to the character set was found. - #[error("A character that does not belong to the character set was found")] - InvalidCharacter, -} - -impl From<qrcode::types::QrError> for Error { - fn from(error: qrcode::types::QrError) -> Self { - use qrcode::types::QrError; - - match error { - QrError::DataTooLong => Error::DataTooLong, - QrError::InvalidVersion => Error::InvalidVersion, - QrError::UnsupportedCharacterSet => Error::UnsupportedCharacterSet, - QrError::InvalidEciDesignator => Error::InvalidEciDesignator, - QrError::InvalidCharacter => Error::InvalidCharacter, - } - } -} |