#![no_main]

use {

    libfuzzer_sys::{fuzz_target, Corpus},

    regex::RegexBuilder,

    regex_syntax::ast::Ast,

};

#[derive(Eq, PartialEq, arbitrary::Arbitrary)]

struct FuzzData {

    ast: Ast,

    haystack: String,

}

impl std::fmt::Debug for FuzzData {

    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {

        let mut builder = f.debug_struct("FuzzData");

        builder.field("ast", &format!("{}", self.ast));

        builder.field("haystack", &self.haystack);

        builder.finish()

    }

}

fuzz_target!(|data: FuzzData| -> Corpus {

    let _ = env_logger::try_init();

    let pattern = format!("{}", data.ast);

    let Ok(re) = RegexBuilder::new(&pattern).size_limit(1 << 20).build()

    else {

        return Corpus::Reject;

    };

    let _ = re.is_match(&data.haystack);

    let _ = re.find(&data.haystack);

    let _ = re.captures(&data.haystack).map_or(0, |c| c.len());

    Corpus::Keep

});