use crate::io::Buf;

#[derive(Debug)]

pub(crate) struct CommandComplete {

pub(crate) affected_rows: u64,

}

impl CommandComplete {

pub(crate) fn read(mut buf: &[u8]) -> crate::Result<Self> {

// Attempt to parse the last word in the command tag as an integer

// If it can't be parsed, the tag is probably "CREATE TABLE" or something

// and we should return 0 rows

let rows = buf

.get_str_nul()?

.rsplit(' ')

.next()

.and_then(|s| s.parse().ok())

.unwrap_or(0);

Ok(Self {

affected_rows: rows,

})

}

}

#[cfg(test)]

mod tests {

use super::CommandComplete;

const COMMAND_COMPLETE_INSERT: &[u8] = b"INSERT 0 1\0";

const COMMAND_COMPLETE_UPDATE: &[u8] = b"UPDATE 512\0";

const COMMAND_COMPLETE_CREATE_TABLE: &[u8] = b"CREATE TABLE\0";

const COMMAND_COMPLETE_BEGIN: &[u8] = b"BEGIN\0";

#[test]

fn it_reads_command_complete_for_insert() {

let message = CommandComplete::read(COMMAND_COMPLETE_INSERT).unwrap();

assert_eq!(message.affected_rows, 1);

}

#[test]

fn it_reads_command_complete_for_update() {

let message = CommandComplete::read(COMMAND_COMPLETE_UPDATE).unwrap();

assert_eq!(message.affected_rows, 512);

}

#[test]

fn it_reads_command_complete_for_begin() {

let message = CommandComplete::read(COMMAND_COMPLETE_BEGIN).unwrap();

assert_eq!(message.affected_rows, 0);

}

#[test]

fn it_reads_command_complete_for_create_table() {

let message = CommandComplete::read(COMMAND_COMPLETE_CREATE_TABLE).unwrap();

assert_eq!(message.affected_rows, 0);

}

}