1
 2
 3
 4
 5
 6
 7
 8
 9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89

use std::fmt;

pub type Result<T> = std::result::Result<T, Error>;

/// The error type for errors that occur whilst reading the header.
///
/// # Notes
///
/// I've opted for specific error messages related to the format of the header so, for example, you
/// would be able to tell the parsing failed because of an unuspported version. However, for IO
/// errors there is just a single error type and it won't be clear which part of the file caused it
/// (because usually it won't matter).
#[derive(Debug)]
pub enum Error {
    Io(std::io::Error),
    InvalidIdentifier,
    UnsupportedReplayVersion(u32),
    UnsupportedResultVersion(u32),
    MissingSpyUsername,
    MissingSniperUsername,
    InvalidString(std::string::FromUtf8Error),
    InvalidGameResult(u32),
    InvalidGameMode(u32),
    UnknownMap(String),
    UnknownMapVariant(u32),
    UnknownGameResult(String),
    UnknownGameMode(String),
    UnknownMission(String),
}

impl fmt::Display for Error {
    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
        match self {
            Error::Io(err) => write!(f, "IO error ({})", err),
            Error::InvalidIdentifier => write!(f, "invalid identifier"),
            Error::UnsupportedReplayVersion(v) => write!(f, "unsupported replay version ({})", v),
            Error::UnsupportedResultVersion(v) => {
                write!(f, "unsupported result data version ({})", v)
            }
            Error::MissingSpyUsername => write!(f, "missing spy username"),
            Error::MissingSniperUsername => write!(f, "missing sniper username"),
            Error::InvalidString(err) => write!(f, "invalid UTF8 string ({})", err),
            Error::InvalidGameResult(result) => write!(f, "invalid game result ({})", result),
            Error::InvalidGameMode(mode) => write!(f, "invalid game mode ({})", mode),
            Error::UnknownMap(map) => write!(f, "unknown map ({})", map),
            Error::UnknownMapVariant(variant) => write!(f, "unknown map variant ({})", variant),
            Error::UnknownGameResult(result) => write!(f, "unknown game result ({})", result),
            Error::UnknownGameMode(mode) => write!(f, "unknown game mode ({})", mode),
            Error::UnknownMission(mission) => write!(f, "unknown mission ({})", mission),
        }
    }
}

impl std::error::Error for Error {
    fn cause(&self) -> Option<&dyn std::error::Error> {
        match self {
            Error::Io(err) => Some(err),
            _ => None,
        }
    }
}

impl From<std::io::Error> for Error {
    fn from(err: std::io::Error) -> Self {
        Error::Io(err)
    }
}

impl From<std::string::FromUtf8Error> for Error {
    fn from(err: std::string::FromUtf8Error) -> Self {
        Error::InvalidString(err)
    }
}

/// Simple macro to allow returning early with an error.
macro_rules! bail {
    ($e:expr) => {
        return Err($e);
    };
}

/// Simple macro to allow returning early with an error if a condition isn't satisfied.
macro_rules! ensure {
    ($cond:expr, $e:expr) => {
        if !($cond) {
            bail!($e);
        }
    };
}