Documentation
#![cfg_attr(not(feature = "std"), no_std)]

#[cfg(feature = "std")]
mod std_tests {
    use std::collections::HashMap;
    use std::convert::{TryFrom, TryInto};
    use std::str::FromStr;

    use cid::{Cid, CidGeneric, Error, Version};
    use multibase::Base;
    use multihash_codetable::{Code, MultihashDigest};

    const RAW: u64 = 0x55;
    const DAG_PB: u64 = 0x70;

    #[test]
    fn basic_marshalling() {
        let h = Code::Sha2_256.digest(b"beep boop");

        let cid = Cid::new_v1(DAG_PB, h);

        let data = cid.to_bytes();
        let out = Cid::try_from(data.clone()).unwrap();
        assert_eq!(cid, out);

        let out2 = data.try_into().unwrap();
        assert_eq!(cid, out2);

        let s = cid.to_string();
        let out3 = Cid::try_from(&s[..]).unwrap();
        assert_eq!(cid, out3);

        let out4 = (&s[..]).try_into().unwrap();
        assert_eq!(cid, out4);
    }

    #[test]
    fn empty_string() {
        assert!(matches!(Cid::try_from(""), Err(Error::InputTooShort)))
    }

    #[test]
    fn v0_handling() {
        let old = "QmdfTbBqBPQ7VNxZEYEj14VmRuZBkqFbiwReogJgS1zR1n";
        let cid = Cid::try_from(old).unwrap();

        assert_eq!(cid.version(), Version::V0);
        assert_eq!(cid.to_string(), old);
    }

    #[test]
    fn from_str() {
        let cid: Cid = "QmdfTbBqBPQ7VNxZEYEj14VmRuZBkqFbiwReogJgS1zR1n"
            .parse()
            .unwrap();
        assert_eq!(cid.version(), Version::V0);

        let bad = "QmdfTbBqBPQ7VNxZEYEj14VmRuZBkqFbiwReogJgS1zIII".parse::<Cid>();
        assert!(matches!(bad, Err(Error::ParsingError)));
    }

    #[test]
    fn v0_error() {
        let bad = "QmdfTbBqBPQ7VNxZEYEj14VmRuZBkqFbiwReogJgS1zIII";
        assert!(matches!(Cid::try_from(bad), Err(Error::ParsingError)));
    }

    #[test]
    fn from() {
        let the_hash = "QmdfTbBqBPQ7VNxZEYEj14VmRuZBkqFbiwReogJgS1zR1n";

        let cases = vec![
            format!("/ipfs/{:}", &the_hash),
            format!("https://ipfs.io/ipfs/{:}", &the_hash),
            format!("http://localhost:8080/ipfs/{:}", &the_hash),
        ];

        for case in cases {
            let cid = Cid::try_from(case).unwrap();
            assert_eq!(cid.version(), Version::V0);
            assert_eq!(cid.to_string(), the_hash);
        }
    }

    #[test]
    fn test_hash() {
        let data: Vec<u8> = vec![1, 2, 3];
        let hash = Code::Sha2_256.digest(&data);
        let mut map = HashMap::new();
        let cid = Cid::new_v0(hash).unwrap();
        map.insert(cid, data.clone());
        assert_eq!(&data, map.get(&cid).unwrap());
    }

    #[test]
    fn test_base32() {
        let cid =
            Cid::from_str("bafkreibme22gw2h7y2h7tg2fhqotaqjucnbc24deqo72b6mkl2egezxhvy").unwrap();
        assert_eq!(cid.version(), Version::V1);
        assert_eq!(cid.codec(), RAW);
        assert_eq!(cid.hash(), &Code::Sha2_256.digest(b"foo"));
    }

    #[test]
    fn to_string() {
        let expected_cid = "bafkreibme22gw2h7y2h7tg2fhqotaqjucnbc24deqo72b6mkl2egezxhvy";
        let cid = Cid::new_v1(RAW, Code::Sha2_256.digest(b"foo"));
        assert_eq!(cid.to_string(), expected_cid);
    }

    #[test]
    fn to_string_of_base32() {
        let expected_cid = "bafkreibme22gw2h7y2h7tg2fhqotaqjucnbc24deqo72b6mkl2egezxhvy";
        let cid = Cid::new_v1(RAW, Code::Sha2_256.digest(b"foo"));
        assert_eq!(
            cid.to_string_of_base(Base::Base32Lower).unwrap(),
            expected_cid
        );
    }

    #[test]
    fn to_string_of_base64() {
        let expected_cid = "mAVUSICwmtGto/8aP+ZtFPB0wQTQTQi1wZIO/oPmKXohiZueu";
        let cid = Cid::new_v1(RAW, Code::Sha2_256.digest(b"foo"));
        assert_eq!(cid.to_string_of_base(Base::Base64).unwrap(), expected_cid);
    }

    #[test]
    fn to_string_of_base58_v0() {
        let expected_cid = "QmRJzsvyCQyizr73Gmms8ZRtvNxmgqumxc2KUp71dfEmoj";
        let cid = Cid::new_v0(Code::Sha2_256.digest(b"foo")).unwrap();
        assert_eq!(
            cid.to_string_of_base(Base::Base58Btc).unwrap(),
            expected_cid
        );
    }

    #[test]
    fn to_string_of_base_v0_error() {
        let cid = Cid::new_v0(Code::Sha2_256.digest(b"foo")).unwrap();
        assert!(matches!(
            cid.to_string_of_base(Base::Base16Upper),
            Err(Error::InvalidCidV0Base)
        ));
    }

    #[test]
    fn explicit_v0_is_disallowed() {
        use std::io::Cursor;
        assert!(matches!(
            Cid::read_bytes(Cursor::new([
                0x00, 0x70, 0x12, 0x12, 0x12, 0x12, 0x12, 0x12, 0x12, 0x12, 0x12, 0x12
            ])),
            Err(Error::InvalidExplicitCidV0)
        ));
    }

    #[test]
    fn new_v0_accepts_only_32_bytes() {
        use multihash::Multihash;
        const SHA2_256: u64 = 0x12;

        for i in 1..64 {
            if i == 32 {
                continue;
            }
            assert!(matches!(
                Cid::new_v0(Multihash::wrap(SHA2_256, &vec![7; i]).unwrap()),
                Err(Error::InvalidCidV0Multihash)
            ));
        }
    }

    fn a_function_that_takes_a_generic_cid<const S: usize>(cid: &CidGeneric<S>) -> String {
        cid.to_string()
    }

    // This test is about having something implemented that used the default size of `Cid`. So the code
    // is using `Cid` instead of `Cid<SomeSize>`. The code will still work with other sizes.
    #[test]
    fn method_can_take_differently_sized_cids() {
        #[derive(Clone, Copy, Debug, Eq, PartialEq, MultihashDigest)]
        #[mh(alloc_size = 128)]
        enum Code128 {
            #[mh(code = 0x12, hasher = multihash_codetable::Sha2_256)]
            Sha2_256,
        }

        let cid_default = Cid::new_v1(RAW, Code::Sha2_256.digest(b"foo"));
        let cid_128 = CidGeneric::<128>::new_v1(RAW, Code128::Sha2_256.digest(b"foo"));

        assert_eq!(
            a_function_that_takes_a_generic_cid(&cid_default),
            a_function_that_takes_a_generic_cid(&cid_128)
        );
    }

    #[test]
    fn test_into_v1() {
        let cid = Cid::from_str("QmTPcW343HGMdoxarwvHHoPhkbo5GfNYjnZkyW5DBtpvLe").unwrap();
        let cid_v1 = cid.into_v1().unwrap();
        assert_eq!(cid_v1.version(), Version::V1);
        assert_eq!(
            cid_v1.to_string(),
            "bafybeiclbsxcvqpfliqcejqz5ghpvw4r7vktjkyk3ruvjvdmam5azct2v4"
        );

        let cid =
            Cid::from_str("bafyreibjo4xmgaevkgud7mbifn3dzp4v4lyaui4yvqp3f2bqwtxcjrdqg4").unwrap();
        let cid_v1 = cid.into_v1().unwrap();
        assert_eq!(cid_v1.version(), Version::V1);
        assert_eq!(cid_v1, cid);
    }
}

#[cfg(all(test, not(feature = "std")))]
mod no_std_tests {
    use cid::Cid;

    #[test]
    fn validate_cid_unwrap_panics() {
        // This should not panic, but should return an error.
        // bad_cid created during fuzz testing
        let bad_cid = [255, 255, 255, 255, 0, 6, 85, 0];
        assert!(Cid::read_bytes(&bad_cid[..]).is_err());
    }
}