TextureSync/server/texture-sync-server/src/persistency/search/mod.rs

69 lines
1.9 KiB
Rust

use crate::model::*;
mod query_filter;
pub use self::query_filter::QueryFilterSyntaxError;
use self::query_filter::*;
pub struct Query {
filters: Vec<QueryFilter>,
}
impl Query {
pub fn search(&self, input: &mut Iterator<Item = &Texture>) -> Vec<Texture> {
let mut results: Vec<(u64, &Texture)> = Vec::new();
// We use pseudo decimal fixed point numbers here.
// 1.000_000 = 1_000_000;
// This is done, since algorithms like quicksort can fail on floats.
let required_score = self.required_score() * 1_000_000u64;
for texture in input {
let mut score = 0u64;
for (pos, filter) in self.filters.iter().enumerate() {
match filter.score(texture) {
Score::RequiredMatch(true) => (),
Score::RequiredMatch(false) => {
// skip this texture
continue;
}
Score::Match(true) => {
score += 1_000_000u64 * (1 + (0.1 / f64::sqrt(pos as f64 + 1.0)) as u64);
}
Score::Match(false) => (),
}
}
if score >= required_score {
results.push((score, texture))
}
}
results.sort_by_key(|(score, _)| *score);
results
.iter()
.map(|(_, texture)| Texture::clone(texture))
.collect::<Vec<Texture>>()
}
fn required_score(&self) -> u64 {
let non_special = self.filters.iter().filter(|f| !f.is_special()).count() as u64;
// ceil(non_special / 2)
(non_special + 1) / 2
}
pub fn parse(input: &[String]) -> Result<Query, QueryFilterSyntaxError> {
let mut result = Query { filters: vec![] };
for fltr in input {
let qryfltr = fltr.parse::<QueryFilter>()?;
result.filters.push(qryfltr);
}
Ok(result)
}
}