ed2e38031c
* uint -> usize * range(a, b) -> (a .. b) * #[deriving] -> #[derive] * [T, ..10] -> [T; 10] * Iterator<X> -> Iterator<Item=X>
294 lines
9.4 KiB
Rust
294 lines
9.4 KiB
Rust
#![unstable]
|
||
|
||
use std::default::Default;
|
||
use std::cmp::{PartialOrd, Ordering};
|
||
|
||
//------------------------------------------------------------------------------
|
||
//{{{ QrResult
|
||
|
||
/// `QrError` encodes the error encountered when generating a QR code.
|
||
#[unstable]
|
||
#[derive(Show, PartialEq, Eq, Copy, Clone)]
|
||
pub enum QrError {
|
||
/// The data is too long to encode into a QR code for the given version.
|
||
DataTooLong,
|
||
|
||
/// The provided version / error correction level combination is invalid.
|
||
InvalidVersion,
|
||
|
||
/// Some characters in the data cannot be supported by the provided QR code
|
||
/// version.
|
||
UnsupportedCharacterSet,
|
||
|
||
/// The provided ECI designator is invalid. A valid designator should be
|
||
/// between 0 and 999999.
|
||
InvalidEciDesignator,
|
||
|
||
/// A character not belonging to the character set is found.
|
||
InvalidCharacter,
|
||
}
|
||
|
||
/// `QrResult` is a convenient alias for a QR code generation result.
|
||
#[stable]
|
||
pub type QrResult<T> = Result<T, QrError>;
|
||
|
||
//}}}
|
||
//------------------------------------------------------------------------------
|
||
//{{{ Error correction level
|
||
|
||
/// The error correction level. It allows the original information be recovered
|
||
/// even if parts of the code is damaged.
|
||
#[derive(Show, PartialEq, Eq, Copy, Clone, PartialOrd, Ord)]
|
||
#[unstable]
|
||
pub enum EcLevel {
|
||
/// Low error correction. Allows up to 7% of wrong blocks.
|
||
L = 0,
|
||
|
||
/// Medium error correction (default). Allows up to 15% of wrong blocks.
|
||
M = 1,
|
||
|
||
/// "Quartile" error correction. Allows up to 25% of wrong blocks.
|
||
Q = 2,
|
||
|
||
/// High error correction. Allows up to 30% of wrong blocks.
|
||
H = 3,
|
||
}
|
||
|
||
//}}}
|
||
//------------------------------------------------------------------------------
|
||
//{{{ Version
|
||
|
||
/// In QR code terminology, `Version` means the size of the generated image.
|
||
/// Larger version means the size of code is larger, and therefore can carry
|
||
/// more information.
|
||
///
|
||
/// The smallest version is `Version::Normal(1)` of size 21×21, and the largest
|
||
/// is `Version::Normal(40)` of size 177×177.
|
||
#[unstable]
|
||
#[derive(Show, PartialEq, Eq, Copy, Clone)]
|
||
pub enum Version {
|
||
/// A normal QR code version. The parameter should be between 1 and 40.
|
||
Normal(i16),
|
||
|
||
/// A Micro QR code version. The parameter should be between 1 and 4.
|
||
Micro(i16),
|
||
}
|
||
|
||
impl Version {
|
||
/// Get the number of "modules" on each size of the QR code, i.e. the width
|
||
/// and height of the code.
|
||
#[unstable]
|
||
pub fn width(&self) -> i16 {
|
||
match *self {
|
||
Version::Normal(v) => v * 4 + 17,
|
||
Version::Micro(v) => v * 2 + 9,
|
||
}
|
||
}
|
||
|
||
/// Obtains an object from a hard-coded table.
|
||
///
|
||
/// The table must be a 44×4 array. The outer array represents the content
|
||
/// for each version. The first 40 entry corresponds to QR code versions 1
|
||
/// to 40, and the last 4 corresponds to Micro QR code version 1 to 4. The
|
||
/// inner array represents the content in each error correction level, in
|
||
/// the order [L, M, Q, H].
|
||
///
|
||
/// If the entry compares equal to the default value of T, this method
|
||
/// returns `Err(QrError::InvalidVersion)`.
|
||
pub fn fetch<T>(&self, ec_level: EcLevel, table: &[[T; 4]]) -> QrResult<T>
|
||
where T: PartialEq + Default + Copy
|
||
{
|
||
match *self {
|
||
Version::Normal(v @ 1...40) => Ok(table[v as usize - 1][ec_level as usize]),
|
||
Version::Micro(v @ 1...4) => {
|
||
let obj = table[v as usize + 39][ec_level as usize];
|
||
if obj != Default::default() {
|
||
Ok(obj)
|
||
} else {
|
||
Err(QrError::InvalidVersion)
|
||
}
|
||
}
|
||
_ => Err(QrError::InvalidVersion)
|
||
}
|
||
}
|
||
|
||
/// The number of bits needed to encode the mode indicator.
|
||
#[unstable]
|
||
pub fn mode_bits_count(&self) -> usize {
|
||
match *self {
|
||
Version::Micro(a) => (a - 1) as usize,
|
||
_ => 4,
|
||
}
|
||
}
|
||
|
||
/// Checks whether is version refers to a Micro QR code.
|
||
#[unstable]
|
||
pub fn is_micro(&self) -> bool {
|
||
match *self {
|
||
Version::Normal(_) => false,
|
||
Version::Micro(_) => true,
|
||
}
|
||
}
|
||
}
|
||
|
||
|
||
//}}}
|
||
//------------------------------------------------------------------------------
|
||
//{{{ Mode indicator
|
||
|
||
/// The mode indicator, which specifies the character set of the encoded data.
|
||
#[unstable]
|
||
#[derive(Show, PartialEq, Eq, Copy, Clone)]
|
||
pub enum Mode {
|
||
/// The data contains only characters 0 to 9.
|
||
Numeric,
|
||
|
||
/// The data contains only uppercase letters (A–Z), numbers (0–9) and a few
|
||
/// punctuations marks (space, `$`, `%`, `*`, `+`, `-`, `.`, `/`, `:`).
|
||
Alphanumeric,
|
||
|
||
/// The data contains arbitrary binary data.
|
||
Byte,
|
||
|
||
/// The data contains Shift-JIS-encoded double-byte text.
|
||
Kanji,
|
||
}
|
||
|
||
impl Mode {
|
||
/// Computes the number of bits needed to encode the data length.
|
||
///
|
||
/// use qrcode::types::{Version, Mode};
|
||
///
|
||
/// assert_eq!(Mode::Numeric.length_bits_count(Version::Normal(1)), 10);
|
||
///
|
||
/// This method will return `Err(QrError::UnsupportedCharacterSet)` if the
|
||
/// mode is not supported in the given version.
|
||
#[unstable]
|
||
pub fn length_bits_count(&self, version: Version) -> usize {
|
||
match version {
|
||
Version::Micro(a) => {
|
||
let a = a as usize;
|
||
match *self {
|
||
Mode::Numeric => 2 + a,
|
||
Mode::Alphanumeric | Mode::Byte => 1 + a,
|
||
Mode::Kanji => a,
|
||
}
|
||
}
|
||
Version::Normal(1...9) => match *self {
|
||
Mode::Numeric => 10,
|
||
Mode::Alphanumeric => 9,
|
||
Mode::Byte => 8,
|
||
Mode::Kanji => 8,
|
||
},
|
||
Version::Normal(10...26) => match *self {
|
||
Mode::Numeric => 12,
|
||
Mode::Alphanumeric => 11,
|
||
Mode::Byte => 16,
|
||
Mode::Kanji => 10,
|
||
},
|
||
Version::Normal(_) => match *self {
|
||
Mode::Numeric => 14,
|
||
Mode::Alphanumeric => 13,
|
||
Mode::Byte => 16,
|
||
Mode::Kanji => 12,
|
||
},
|
||
}
|
||
}
|
||
|
||
/// Computes the number of bits needed to some data of a given raw length.
|
||
///
|
||
/// use qrcode::types::Mode;
|
||
///
|
||
/// assert_eq!(Mode::Numeric.data_bits_count(7), 24);
|
||
///
|
||
/// Note that in Kanji mode, the `raw_data_len` is the number of Kanjis,
|
||
/// i.e. half the total size of bytes.
|
||
#[unstable]
|
||
pub fn data_bits_count(&self, raw_data_len: usize) -> usize {
|
||
match *self {
|
||
Mode::Numeric => (raw_data_len * 10 + 2) / 3,
|
||
Mode::Alphanumeric => (raw_data_len * 11 + 1) / 2,
|
||
Mode::Byte => raw_data_len * 8,
|
||
Mode::Kanji => raw_data_len * 13,
|
||
}
|
||
}
|
||
|
||
/// Find the lowest common mode which both modes are compatible with.
|
||
///
|
||
/// use qrcode::types::Mode;
|
||
///
|
||
/// let a = Mode::Numeric;
|
||
/// let b = Mode::Kanji;
|
||
/// let c = a.max(b);
|
||
/// assert!(a <= c);
|
||
/// assert!(b <= c);
|
||
///
|
||
pub fn max(&self, other: Mode) -> Mode {
|
||
match self.partial_cmp(&other) {
|
||
Some(Ordering::Less) | Some(Ordering::Equal) => other,
|
||
Some(Ordering::Greater) => *self,
|
||
None => Mode::Byte,
|
||
}
|
||
}
|
||
}
|
||
|
||
impl PartialOrd for Mode {
|
||
/// Defines a partial ordering between modes. If `a <= b`, then `b` contains
|
||
/// a superset of all characters supported by `a`.
|
||
fn partial_cmp(&self, other: &Mode) -> Option<Ordering> {
|
||
match (*self, *other) {
|
||
(Mode::Numeric, Mode::Alphanumeric) => Some(Ordering::Less),
|
||
(Mode::Alphanumeric, Mode::Numeric) => Some(Ordering::Greater),
|
||
(Mode::Numeric, Mode::Byte) => Some(Ordering::Less),
|
||
(Mode::Byte, Mode::Numeric) => Some(Ordering::Greater),
|
||
(Mode::Alphanumeric, Mode::Byte) => Some(Ordering::Less),
|
||
(Mode::Byte, Mode::Alphanumeric) => Some(Ordering::Greater),
|
||
(Mode::Kanji, Mode::Byte) => Some(Ordering::Less),
|
||
(Mode::Byte, Mode::Kanji) => Some(Ordering::Greater),
|
||
(a, b) if a == b => Some(Ordering::Equal),
|
||
_ => None,
|
||
}
|
||
}
|
||
}
|
||
|
||
#[cfg(test)]
|
||
mod mode_tests {
|
||
use types::Mode::{Numeric, Alphanumeric, Byte, Kanji};
|
||
|
||
#[test]
|
||
fn test_mode_order() {
|
||
assert!(Numeric < Alphanumeric);
|
||
assert!(Byte > Kanji);
|
||
assert!(!(Numeric < Kanji));
|
||
assert!(!(Numeric >= Kanji));
|
||
}
|
||
|
||
#[test]
|
||
fn test_max() {
|
||
assert_eq!(Byte.max(Kanji), Byte);
|
||
assert_eq!(Numeric.max(Alphanumeric), Alphanumeric);
|
||
assert_eq!(Alphanumeric.max(Alphanumeric), Alphanumeric);
|
||
assert_eq!(Numeric.max(Kanji), Byte);
|
||
assert_eq!(Kanji.max(Numeric), Byte);
|
||
assert_eq!(Alphanumeric.max(Numeric), Alphanumeric);
|
||
assert_eq!(Kanji.max(Kanji), Kanji);
|
||
}
|
||
}
|
||
|
||
//}}}
|
||
|
||
// Copyright 2014 Kenny Chan
|
||
//
|
||
// 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.
|
||
|