use alloc::fmt::{self, Debug, Formatter};
use core::ops::Deref;
use core::slice::Iter;
use alloc::string::String;
use alloc::vec::Vec;
#[allow(clippy::len_without_is_empty)]
pub trait BMByteSearchable {
fn len(&self) -> usize;
fn value_at(&self, index: usize) -> u8;
fn iter(&self) -> Iter<u8>;
}
impl BMByteSearchable for String {
#[inline]
fn len(&self) -> usize {
String::len(self)
}
#[inline]
fn value_at(&self, index: usize) -> u8 {
self.as_bytes()[index]
}
#[inline]
fn iter(&self) -> Iter<u8> {
self.as_bytes().iter()
}
}
impl BMByteSearchable for &str {
#[inline]
fn len(&self) -> usize {
str::len(self)
}
#[inline]
fn value_at(&self, index: usize) -> u8 {
unsafe { (*(*self as *const str as *const [u8]))[index] }
}
#[inline]
fn iter(&self) -> Iter<u8> {
self.as_bytes().iter()
}
}
impl BMByteSearchable for dyn Deref<Target = [u8]> {
#[inline]
fn len(&self) -> usize {
<[u8]>::len(self)
}
#[inline]
fn value_at(&self, index: usize) -> u8 {
self[index]
}
#[inline]
fn iter(&self) -> Iter<u8> {
<[u8]>::iter(self)
}
}
impl BMByteSearchable for Vec<u8> {
#[inline]
fn len(&self) -> usize {
Vec::len(self)
}
#[inline]
fn value_at(&self, index: usize) -> u8 {
self[index]
}
#[inline]
fn iter(&self) -> Iter<u8> {
self.as_slice().iter()
}
}
impl<T: BMByteSearchable> BMByteSearchable for &T {
#[inline]
fn len(&self) -> usize {
<dyn BMByteSearchable>::len(*self)
}
#[inline]
fn value_at(&self, index: usize) -> u8 {
<dyn BMByteSearchable>::value_at(*self, index)
}
#[inline]
fn iter(&self) -> Iter<u8> {
<dyn BMByteSearchable>::iter(*self)
}
}
pub struct BMByteBadCharShiftMap {
t: [usize; 256],
}
impl Debug for BMByteBadCharShiftMap {
#[inline]
fn fmt(&self, f: &mut Formatter) -> Result<(), fmt::Error> {
debug_helper::impl_debug_for_struct!(BMByteBadCharShiftMap, f, self, let .t = self.t.as_ref());
}
}
impl Deref for BMByteBadCharShiftMap {
type Target = [usize];
#[inline]
fn deref(&self) -> &[usize] {
self.t.as_ref()
}
}
pub struct BMByteBadCharShiftMapRev {
t: [usize; 256],
}
impl Debug for BMByteBadCharShiftMapRev {
#[inline]
fn fmt(&self, f: &mut Formatter) -> Result<(), fmt::Error> {
debug_helper::impl_debug_for_struct!(BMByteBadCharShiftMapRev, f, self, let .t = self.t.as_ref());
}
}
impl Deref for BMByteBadCharShiftMapRev {
type Target = [usize];
#[inline]
fn deref(&self) -> &[usize] {
self.t.as_ref()
}
}
impl BMByteBadCharShiftMap {
pub fn create_bad_char_shift_map<T: BMByteSearchable>(
pattern: T,
) -> Option<BMByteBadCharShiftMap> {
let pattern_len = pattern.len();
if pattern_len == 0 {
return None;
}
let pattern_len_dec = pattern_len - 1;
let mut bad_char_shift_map = [pattern_len; 256];
for (i, c) in pattern.iter().take(pattern_len_dec).map(|&c| c as usize).enumerate() {
bad_char_shift_map[c] = pattern_len_dec - i;
}
Some(BMByteBadCharShiftMap {
t: bad_char_shift_map,
})
}
}
impl BMByteBadCharShiftMapRev {
pub fn create_bad_char_shift_map<T: BMByteSearchable>(
pattern: T,
) -> Option<BMByteBadCharShiftMapRev> {
let pattern_len = pattern.len();
if pattern_len == 0 {
return None;
}
let pattern_len_dec = pattern_len - 1;
let mut bad_char_shift_map = [pattern_len; 256];
for (i, c) in
pattern.iter().enumerate().rev().take(pattern_len_dec).map(|(i, &c)| (i, c as usize))
{
bad_char_shift_map[c] = i;
}
Some(BMByteBadCharShiftMapRev {
t: bad_char_shift_map,
})
}
}
#[derive(Debug)]
pub struct BMByte {
bad_char_shift_map: BMByteBadCharShiftMap,
bad_char_shift_map_rev: BMByteBadCharShiftMapRev,
pattern: Vec<u8>,
}
impl BMByte {
pub fn from<T: BMByteSearchable>(pattern: T) -> Option<BMByte> {
let bad_char_shift_map = BMByteBadCharShiftMap::create_bad_char_shift_map(&pattern)?;
let bad_char_shift_map_rev = BMByteBadCharShiftMapRev::create_bad_char_shift_map(&pattern)?;
Some(BMByte {
bad_char_shift_map,
bad_char_shift_map_rev,
pattern: pattern.iter().copied().collect(),
})
}
}
impl BMByte {
pub fn find_full_all_in<T: BMByteSearchable>(&self, text: T) -> Vec<usize> {
find_full(text, &self.pattern, &self.bad_char_shift_map, 0)
}
pub fn find_full_in<T: BMByteSearchable>(&self, text: T, limit: usize) -> Vec<usize> {
find_full(text, &self.pattern, &self.bad_char_shift_map, limit)
}
}
impl BMByte {
pub fn rfind_full_all_in<T: BMByteSearchable>(&self, text: T) -> Vec<usize> {
rfind_full(text, &self.pattern, &self.bad_char_shift_map_rev, 0)
}
pub fn rfind_full_in<T: BMByteSearchable>(&self, text: T, limit: usize) -> Vec<usize> {
rfind_full(text, &self.pattern, &self.bad_char_shift_map_rev, limit)
}
}
pub fn find_full<TT: BMByteSearchable, TP: BMByteSearchable>(
text: TT,
pattern: TP,
bad_char_shift_map: &BMByteBadCharShiftMap,
limit: usize,
) -> Vec<usize> {
let text_len = text.len();
let pattern_len = pattern.len();
if text_len == 0 || pattern_len == 0 || text_len < pattern_len {
return vec![];
}
let pattern_len_dec = pattern_len - 1;
let last_pattern_char = pattern.value_at(pattern_len_dec);
let mut shift = 0;
let end_index = text_len - pattern_len;
let mut result = vec![];
'outer: loop {
for (i, pc) in pattern.iter().copied().enumerate().rev() {
if text.value_at(shift + i) != pc {
let p = shift + pattern_len;
if p == text_len {
break 'outer;
}
shift += bad_char_shift_map[text.value_at(shift + pattern_len_dec) as usize].max({
let c = text.value_at(p);
if c == last_pattern_char {
1
} else {
bad_char_shift_map[c as usize] + 1
}
});
if shift > end_index {
break 'outer;
}
continue 'outer;
}
}
result.push(shift);
if shift == end_index {
break;
}
if result.len() == limit {
break;
}
shift += bad_char_shift_map[text.value_at(shift + pattern_len_dec) as usize].max({
let c = text.value_at(shift + pattern_len);
if c == last_pattern_char {
1
} else {
bad_char_shift_map[c as usize] + 1
}
});
if shift > end_index {
break;
}
}
result
}
pub fn rfind_full<TT: BMByteSearchable, TP: BMByteSearchable>(
text: TT,
pattern: TP,
bad_char_shift_map: &BMByteBadCharShiftMapRev,
limit: usize,
) -> Vec<usize> {
let text_len = text.len();
let pattern_len = pattern.len();
if text_len == 0 || pattern_len == 0 || text_len < pattern_len {
return vec![];
}
let pattern_len_dec = pattern_len - 1;
let first_pattern_char = pattern.value_at(0);
let mut shift = text_len - 1;
let start_index = pattern_len_dec;
let mut result = vec![];
'outer: loop {
for (i, pc) in pattern.iter().copied().enumerate() {
if text.value_at(shift - pattern_len_dec + i) != pc {
if shift < pattern_len {
break 'outer;
}
let s = bad_char_shift_map[text.value_at(shift - pattern_len_dec) as usize].max({
let c = text.value_at(shift - pattern_len);
if c == first_pattern_char {
1
} else {
bad_char_shift_map[c as usize] + 1
}
});
if shift < s {
break 'outer;
}
shift -= s;
if shift < start_index {
break 'outer;
}
continue 'outer;
}
}
result.push(shift - pattern_len_dec);
if shift == start_index {
break;
}
if result.len() == limit {
break;
}
let s = bad_char_shift_map[text.value_at(shift - pattern_len_dec) as usize].max({
let c = text.value_at(shift - pattern_len);
if c == first_pattern_char {
1
} else {
bad_char_shift_map[c as usize] + 1
}
});
if shift < s {
break;
}
shift -= s;
if shift < start_index {
break;
}
}
result
}
impl BMByte {
pub fn find_all_in<T: BMByteSearchable>(&self, text: T) -> Vec<usize> {
find(text, &self.pattern, &self.bad_char_shift_map, 0)
}
pub fn find_first_in<T: BMByteSearchable>(&self, text: T) -> Option<usize> {
find(text, &self.pattern, &self.bad_char_shift_map, 1).first().copied()
}
pub fn find_in<T: BMByteSearchable>(&self, text: T, limit: usize) -> Vec<usize> {
find(text, &self.pattern, &self.bad_char_shift_map, limit)
}
}
impl BMByte {
pub fn rfind_all_in<T: BMByteSearchable>(&self, text: T) -> Vec<usize> {
rfind(text, &self.pattern, &self.bad_char_shift_map_rev, 0)
}
pub fn rfind_first_in<T: BMByteSearchable>(&self, text: T) -> Option<usize> {
rfind(text, &self.pattern, &self.bad_char_shift_map_rev, 1).first().copied()
}
pub fn rfind_in<T: BMByteSearchable>(&self, text: T, limit: usize) -> Vec<usize> {
rfind(text, &self.pattern, &self.bad_char_shift_map_rev, limit)
}
}
pub fn find<TT: BMByteSearchable, TP: BMByteSearchable>(
text: TT,
pattern: TP,
bad_char_shift_map: &BMByteBadCharShiftMap,
limit: usize,
) -> Vec<usize> {
let text_len = text.len();
let pattern_len = pattern.len();
if text_len == 0 || pattern_len == 0 || text_len < pattern_len {
return vec![];
}
let pattern_len_dec = pattern_len - 1;
let last_pattern_char = pattern.value_at(pattern_len_dec);
let mut shift = 0;
let end_index = text_len - pattern_len;
let mut result = vec![];
'outer: loop {
for (i, pc) in pattern.iter().copied().enumerate().rev() {
if text.value_at(shift + i) != pc {
let p = shift + pattern_len;
if p == text_len {
break 'outer;
}
shift += bad_char_shift_map[text.value_at(shift + pattern_len_dec) as usize].max({
let c = text.value_at(p);
if c == last_pattern_char {
1
} else {
bad_char_shift_map[c as usize] + 1
}
});
if shift > end_index {
break 'outer;
}
continue 'outer;
}
}
result.push(shift);
if shift == end_index {
break;
}
if result.len() == limit {
break;
}
shift += pattern_len;
if shift > end_index {
break;
}
}
result
}
pub fn rfind<TT: BMByteSearchable, TP: BMByteSearchable>(
text: TT,
pattern: TP,
bad_char_shift_map: &BMByteBadCharShiftMapRev,
limit: usize,
) -> Vec<usize> {
let text_len = text.len();
let pattern_len = pattern.len();
if text_len == 0 || pattern_len == 0 || text_len < pattern_len {
return vec![];
}
let pattern_len_dec = pattern_len - 1;
let first_pattern_char = pattern.value_at(0);
let mut shift = text_len - 1;
let start_index = pattern_len_dec;
let mut result = vec![];
'outer: loop {
for (i, pc) in pattern.iter().copied().enumerate() {
if text.value_at(shift - pattern_len_dec + i) != pc {
if shift < pattern_len {
break 'outer;
}
let s = bad_char_shift_map[text.value_at(shift - pattern_len_dec) as usize].max({
let c = text.value_at(shift - pattern_len);
if c == first_pattern_char {
1
} else {
bad_char_shift_map[c as usize] + 1
}
});
if shift < s {
break 'outer;
}
shift -= s;
if shift < start_index {
break 'outer;
}
continue 'outer;
}
}
result.push(shift - pattern_len_dec);
if shift == start_index {
break;
}
if result.len() == limit {
break;
}
shift -= pattern_len;
if shift < start_index {
break;
}
}
result
}