use crate::*;


pub fn format_inhx32(segments: &[Segment]) -> Result<Vec<u8>, FormatError> {
    let mut records = Vec::new();
    let mut address = 0;
    records.push(extended_linear_address(0));
    for segment in segments {
        if (segment.address >> 16) != (address >> 16) {
            records.push(extended_linear_address(segment.address));
        }
        address = segment.address;
        for chunk in segment.words.chunks(8) {
            records.push(data_record(chunk, address)?);
            address += 8;
        }
    }
    records.push(terminating_record());

    let mut output = String::new();
    for record in records {
        output.push_str(&record.to_string());
    }
    return Ok(output.into_bytes());
}

fn data_record(words: &[Tracked<Word>], address: usize) -> Result<InhxRecord, FormatError> {
    let Ok(address) = u32::try_from(address * 2) else {
        return Err(FormatError::AddressTooLarge(u32::MAX as usize / 2, address));
    };
    let address = address as u16;
    let mut record = InhxRecord::new();
    record.byte((words.len() * 2) as u8);
    record.be_double(address);
    record.byte(0x00);
    for word in words {
        if word.value.width > 16 {
            return Err(FormatError::WordTooWide(16, word.width, word.source.clone()));
        }
        record.le_double(word.value.value as u16);
    }
    return Ok(record);
}

fn extended_linear_address(address: usize) -> InhxRecord {
    let address = (address >> 16) as u16;
    let mut record = InhxRecord::new();
    record.byte(0x02);
    record.be_double(0x0000);
    record.byte(0x04);
    record.be_double(address);
    return record;
}

fn terminating_record() -> InhxRecord {
    let mut record = InhxRecord::new();
    record.byte(0x00);
    record.be_double(0x0000);
    record.byte(0x01);
    return record;
}