use std::convert::TryFrom;
use tendermint_proto::types::BlockId as RawBlockId;
use tendermint_proto::types::PartSetHeader as RawPartSetHeader;
use tendermint_proto::Protobuf;

impl Protobuf<RawBlockId> for BlockId {}

// Example implementation of a protobuf struct using Protobuf.
#[derive(Clone, Debug)]
pub struct BlockId {
    hash: String,
    part_set_header_exists: bool,
}

// Domain types MUST have the TryFrom trait to convert from Protobuf messages.
impl TryFrom<RawBlockId> for BlockId {
    type Error = &'static str;

    fn try_from(value: RawBlockId) -> Result<Self, Self::Error> {
        Ok(BlockId {
            hash: String::from_utf8(value.hash)
                .map_err(|_| "Could not convert vector to string")?,
            part_set_header_exists: value.part_set_header != None,
        })
    }
}

// Domain types MUST be able to convert to Protobuf messages without errors using the From trait.
impl From<BlockId> for RawBlockId {
    fn from(value: BlockId) -> Self {
        RawBlockId {
            hash: value.hash.into_bytes(),
            part_set_header: match value.part_set_header_exists {
                true => Some(RawPartSetHeader {
                    total: 0,
                    hash: vec![],
                }),
                false => None,
            },
        }
    }
}

// Do any custom implementation for your type
impl PartialEq for BlockId {
    fn eq(&self, other: &Self) -> bool {
        self.part_set_header_exists == other.part_set_header_exists && self.hash == other.hash
    }
}

#[test]
pub fn protobuf_struct_example() {
    let my_domain_type = BlockId {
        hash: "Hello world!".to_string(),
        part_set_header_exists: false,
    };

    let mut wire = vec![];
    my_domain_type.encode(&mut wire).unwrap();
    assert_eq!(
        wire,
        vec![10, 12, 72, 101, 108, 108, 111, 32, 119, 111, 114, 108, 100, 33]
    );
    let new_domain_type = BlockId::decode(wire.as_ref()).unwrap();
    assert_eq!(new_domain_type.hash, "Hello world!".to_string());
    assert!(!new_domain_type.part_set_header_exists);
    assert_eq!(my_domain_type.encoded_len(), 14);
}

#[test]
pub fn protobuf_struct_length_delimited_example() {
    let my_domain_type = BlockId {
        hash: "Hello world!".to_string(),
        part_set_header_exists: false,
    };

    let mut wire = vec![];
    my_domain_type.encode_length_delimited(&mut wire).unwrap();
    assert_eq!(
        wire,
        vec![14, 10, 12, 72, 101, 108, 108, 111, 32, 119, 111, 114, 108, 100, 33]
    );

    let new_domain_type = BlockId::decode_length_delimited(wire.as_ref()).unwrap();
    assert_eq!(new_domain_type.hash, "Hello world!".to_string());
    assert!(!new_domain_type.part_set_header_exists);
}

#[test]
pub fn protobuf_struct_conveniences_example() {
    let my_domain_type = BlockId {
        hash: "Hello world!".to_string(),
        part_set_header_exists: false,
    };

    let wire = my_domain_type.encode_vec().unwrap();
    assert_eq!(
        wire,
        vec![10, 12, 72, 101, 108, 108, 111, 32, 119, 111, 114, 108, 100, 33]
    );
    let new_domain_type = BlockId::decode_vec(&wire).unwrap();
    assert_eq!(my_domain_type, new_domain_type);

    let wire = my_domain_type.encode_length_delimited_vec().unwrap();
    assert_eq!(
        wire,
        vec![14, 10, 12, 72, 101, 108, 108, 111, 32, 119, 111, 114, 108, 100, 33]
    );
    let new_domain_type = BlockId::decode_length_delimited_vec(&wire).unwrap();
    assert_eq!(my_domain_type, new_domain_type);
}