use crate::common::{read_string_with_length, write_string_with_length};
use crate::map_property::MabSubProperty;
use binrw::{BinRead, BinResult, binrw};

#[binrw::parser(reader, endian)]
fn custom_parser(size_in_bytes: u32, value_type: &str) -> BinResult<Vec<ArrayEntry>> {
    let mut result = Vec::<ArrayEntry>::new();

    let mut current = reader.stream_position()?;
    let end = current + size_in_bytes as u64 - 4;

    while current < end {
        result.push(ArrayEntry::read_options(reader, endian, (value_type,))?);
        current = reader.stream_position()?;
    }
    Ok(result)
}

#[binrw]
#[derive(Debug)]
#[br(import(value_type: &str))]
pub struct ArrayEntry {
    #[br(args { magic: &value_type })]
    pub key: MabSubProperty,
}

fn calc_size_in_bytes(entries: &Vec<ArrayEntry>) -> u32 {
    // TODO: stub
    18
}

#[binrw]
#[derive(Debug)]
pub struct ArrayProperty {
    #[bw(calc = calc_size_in_bytes(entries))]
    pub size_in_bytes: u32,

    #[brw(pad_before = 4)]
    #[br(parse_with = read_string_with_length)]
    #[bw(write_with = write_string_with_length)]
    pub key_name: String,

    #[brw(pad_before = 1)]
    #[bw(calc = 1)]
    pub unk: u32,

    #[br(parse_with = custom_parser, args(size_in_bytes, &key_name))]
    pub entries: Vec<ArrayEntry>,
}

#[cfg(test)]
mod tests {
    use super::*;
    use crate::map_property::MabSubProperty::String;
    use binrw::{BinRead, BinWrite};
    use std::io::Cursor;
    use crate::map_property::MapSubStrProperty;

    #[test]
    fn read_simple_array() {
        // From Slot.sav
        let data = [
            0x12, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x0c, 0x00, 0x00, 0x00, 0x53, 0x74,
            0x72, 0x50, 0x72, 0x6f, 0x70, 0x65, 0x72, 0x74, 0x79, 0x00, 0x00, 0x01, 0x00, 0x00,
            0x00, 0x0a, 0x00, 0x00, 0x00, 0x72, 0x65, 0x64, 0x73, 0x74, 0x72, 0x61, 0x74, 0x65,
            0x00,
        ];
        let mut cursor = Cursor::new(data);
        let decoded = ArrayProperty::read_le(&mut cursor).unwrap();
        assert_eq!(decoded.key_name, "StrProperty");
        let String(value_property) = &decoded.entries.first().unwrap().key else {
            panic!("StrProperty!")
        };
        assert_eq!(value_property.value, "redstrate");
    }

    #[test]
    fn write_simple_array() {
        let expected_data: [u8; 43] = [
            0x12, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x0c, 0x00, 0x00, 0x00, 0x53, 0x74,
            0x72, 0x50, 0x72, 0x6f, 0x70, 0x65, 0x72, 0x74, 0x79, 0x00, 0x00, 0x01, 0x00, 0x00,
            0x00, 0x0a, 0x00, 0x00, 0x00, 0x72, 0x65, 0x64, 0x73, 0x74, 0x72, 0x61, 0x74, 0x65,
            0x00,
        ];
        let property = ArrayProperty {
            key_name: "StrProperty".to_string(),
            entries: vec![
                ArrayEntry {
                    key: String(MapSubStrProperty {
                        value: "redstrate".to_string(),
                    }),
                }
            ],
        };

        let mut buffer: Vec<u8> = Vec::new();
        {
            let mut cursor = Cursor::new(&mut buffer);
            property.write_le(&mut cursor).unwrap();
        }

        assert_eq!(expected_data, &buffer[..]);
    }
}