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use crate::{simple_match::*, utils::extract_string_element_by_index};
/// Methods to split a longer strong on a separator and return a vector of strings,
/// a tuple of two strings or single optional string segment
/// Note some methods may return empty segments in the case of leading, trailing or repeated separators
/// See notes below
pub trait ToSegments {
/// Extract a vector of non-empty strings from a string-like object with a given separator
/// excluding leading, trailing or double separators
fn to_segments(&self, separator: &str) -> Vec<String>;
/// Extract a vector of strings from a string-like object with a given separator
fn to_parts(&self, separator: &str) -> Vec<String>;
/// Extract only the head before the first occurrence of a separator
fn to_head(&self, separator: &str) -> String;
/// Extract only the first segment before the first occurrence of a non-initial separator
fn to_first(&self, separator: &str) -> String;
/// Extract only the remainder after the first occurrence of a non-initial separator
fn to_remainder_end(&self, separator: &str) -> String;
/// Extract only the last segment after the last occurrence of a non-final separator
fn to_last(&self, separator: &str) -> String;
/// Extract only the beginning before the last segment following the last occurrence of a non-final separator
fn to_remainder_start(&self, separator: &str) -> String;
/// Extract only the last segment
fn to_end(&self, separator: &str) -> String;
/// Extract the start before the last occurrence of the separator
/// or the whole string if the separator is absent
fn to_start(&self, separator: &str) -> String;
/// Extract a non-empty segment identified by its index from the components of a string with a given separator
/// e.g. String::from("/User/maria/Documents") .to_segment(1) yields "maria"
/// with the leading slash separator ignored
/// A negative index parameter will start from the end ignoring trailing separators
fn to_segment(&self, separator: &str, index: i32) -> Option<String> {
let parts = self.to_segments(separator);
extract_string_element_by_index(parts, index)
}
/// Extract a part identified by its index from the components of a string with a given separator
/// e.g. String::from("10/11/2024") .to_parts(1) yields "11"
/// A negative index parameter will start from the end
fn to_part(&self, separator: &str, index: i32) -> Option<String> {
let parts = self.to_parts(separator);
extract_string_element_by_index(parts, index)
}
/// Extract an inner segment via a set of separator + index tuples
fn to_inner_segment(&self, groups: &[(&str, i32)]) -> Option<String>;
/// extract the remainder after the head
fn to_tail(&self, separator: &str) -> String;
/// extract the first and last parts after the first occurrence of the separator
fn to_head_tail(&self, separator: &str) -> (String, String);
/// extract the first and last parts after the last occurrence of the separator
fn to_start_end(&self, separator: &str) -> (String, String);
}
/// Implement string segment split and capture method for String
impl ToSegments for str {
/// Splits a string on the exact separator, whether initial, final or repeated.
/// May yield empty segments
fn to_parts(&self, separator: &str) -> Vec<String> {
let splitter = self.split(separator);
splitter.into_iter().map(|s| s.to_string()).collect::<Vec<String>>()
}
/// Splits a string on a separator, but only returns an array of non-empty strings
/// skipping leading, trailing or repeated separators that may otherwise yield empty strings
fn to_segments(&self, separator: &str) -> Vec<String> {
let splitter = self.split(separator);
splitter.into_iter().map(|s| s.to_string()).filter(|s| s.len() > 0).collect::<Vec<String>>()
}
/// Extract only the head as a string. If the separator is absent return the whole string
fn to_head(&self, separator: &str) -> String {
if let Some((head, _tail)) = self.split_once(separator) {
head.to_string()
} else {
self.to_owned()
}
}
/// Extract only the last segment after the last occurrence of a non-final separator
fn to_last(&self, separator: &str) -> String {
let separator_len = separator.len();
if self.ends_with(separator) && self.len() > separator_len {
let end_index = self.len() - separator_len;
self[0..end_index].to_string().to_end(separator)
} else {
self.to_end(separator)
}
}
/// extract the last segment whether empty or not
fn to_end(&self, separator: &str) -> String {
let (_start, end) = self.to_start_end(separator);
end
}
/// extract the start before last occurrence of the separator
/// or, if absent, return the whole string
fn to_start(&self, separator: &str) -> String {
let (start, _end) = self.to_start_end(separator);
start
}
/// extract the remainder after the first split
/// or the whole string if the separator is absent
fn to_tail(&self, separator: &str) -> String {
let parts = self.to_parts(separator);
let num_parts = parts.len();
if num_parts > 0 {
parts[1..num_parts].join(separator)
} else {
self.to_owned()
}
}
/// Extract only the first segment before the first occurrence of a non-initial separator
fn to_first(&self, separator: &str) -> String {
let separator_len = separator.len();
if self.starts_with(separator) && self.len() > separator_len {
self[separator_len..self.len()].to_string().to_head(separator)
} else {
self.to_head(separator)
}
}
/// Extract only the remainder after the first occurrence of a non-initial separator
fn to_remainder_end(&self, separator: &str) -> String {
let separator_len = separator.len();
if self.starts_with(separator) && self.len() > separator_len {
self[separator_len..].to_string().to_tail(separator)
} else {
self.to_tail(separator)
}
}
/// Extract only the beginning before the last segment following the last occurrence of a non-final separator
fn to_remainder_start(&self, separator: &str) -> String {
let separator_len = separator.len();
if self.ends_with(separator) && self.len() > separator_len {
let end_index = self.len() - separator_len;
self[0..end_index].to_string().to_start(separator)
} else {
self.to_start(separator)
}
}
/// extract an inner segment via a set of tuples with separators and indices.
/// e.g. [("/", 1), ("-", 2)] applied to "pictures/holiday-france-1983/originals"
/// would match "1983" as an optional string
fn to_inner_segment(&self, groups: &[(&str, i32)]) -> Option<String> {
if groups.len() > 0 {
let mut matched: Option<String> = None;
let mut current_string = self.to_string();
for group in groups {
if current_string.len() > 0 {
let (separator, index) = group;
matched = current_string.to_segment(*separator, *index);
current_string = matched.clone().unwrap_or("".to_string());
}
}
matched
} else {
None
}
}
/// Extract a tuple of the head and remainder
/// like split_once but returninga tuple of strings
/// If the separator is absent or at the start, the first part will be empty
fn to_head_tail(&self, separator: &str) -> (String, String) {
if let Some((head, tail)) = self.split_once(separator) {
(head.to_string(), tail.to_string())
} else {
("".to_owned(), self.to_owned())
}
}
/// Extract a tuple of the start and the last part
/// like split_once in reverse and returning a tuple of strings
/// If the separator is absent or at the end, the second part will be empty
fn to_start_end(&self, separator: &str) -> (String, String) {
if let Some((start, end)) = self.rsplit_once(separator) {
(start.to_string(), end.to_string())
} else {
(self.to_owned(), "".to_string())
}
}
}
/// Methods to split a &str/String on the first matched separator character
pub trait ToSegmentsFromChars {
/// Split a string into parts separated by any of the referenced split characters
fn split_on_any_char(&self, separators: &[char]) -> Vec<String>;
/// Split a string into a head and tail separated by the first instance of the first matching separator
/// If none of the separators are matched, the first element is
/// an empty string and the second the whole string
fn to_head_tail_on_any_char(&self, separators: &[char]) -> (String, String);
/// Split a string into s start and tail separated by the last instance of the first matching separator
/// If none of the separators are matched, the first element is
/// an empty string and the second the whole string
fn to_start_end_on_any_char(&self, separators: &[char]) -> (String, String);
}
impl ToSegmentsFromChars for str {
/// Split a string on any of the referenced characters
fn split_on_any_char(&self, separators: &[char]) -> Vec<String> {
let mut parts: Vec<String> = Vec::new();
let mut has_match = false;
let mut indices: Vec<usize> = Vec::new();
for separator in separators {
for matched_index in self.find_char_indices(*separator) {
indices.push(matched_index);
}
}
indices.sort_by(|a, b| a.cmp(b));
let mut prev_start = 0;
for index in indices {
let segment = self[prev_start..index].to_string();
parts.push(segment);
has_match = true;
prev_start = index + 1;
}
if has_match {
parts.push(self[prev_start..].to_string());
parts
} else {
vec![self.to_owned()]
}
}
/// Split into head and tail components on the first occurrence of any of the referenced characters
fn to_head_tail_on_any_char(&self, separators: &[char]) -> (String, String) {
for ch in separators {
if self.contains(*ch) {
if let Some ((first, second)) = self.split_once(*ch) {
return (first.to_string(), second.to_string());
}
}
}
("".to_owned(), self.to_string())
}
/// Split into start and end components on the last occurrence of any of the referenced characters
fn to_start_end_on_any_char(&self, separators: &[char]) -> (String, String) {
for ch in separators {
if self.contains(*ch) {
if let Some ((first, second)) = self.rsplit_once(*ch) {
return (first.to_string(), second.to_string());
}
}
}
(self.to_string(), "".to_owned())
}
}