1  use std::fmt;
 2  
 3  #[derive(Debug, Clone, PartialEq, Eq)]
 4  pub enum Error {
 5      InvalidUtf8 { offset: usize, reason: String },
 6      UnclosedQuote { quote_type: &'static str, offset: usize },
 7      InvalidKey { offset: usize, reason: String },
 8      ForbiddenWhitespace { location: &'static str, offset: usize },
 9      DoubleEquals { offset: usize },
10      InvalidBom { offset: usize },
11      Expected { offset: usize, expected: &'static str },
12      Generic { offset: usize, message: String },
13      Io(String),
14  }
15  
16  impl Error {
17      pub fn offset(&self) -> usize {
18          match self {
19              Error::InvalidUtf8 { offset, .. } => *offset,
20              Error::UnclosedQuote { offset, .. } => *offset,
21              Error::InvalidKey { offset, .. } => *offset,
22              Error::ForbiddenWhitespace { offset, .. } => *offset,
23              Error::DoubleEquals { offset } => *offset,
24              Error::InvalidBom { offset } => *offset,
25              Error::Expected { offset, .. } => *offset,
26              Error::Generic { offset, .. } => *offset,
27              Error::Io(_) => 0,
28          }
29      }
30  }
31  
32  impl fmt::Display for Error {
33      fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
34          match self {
35              Error::InvalidUtf8 { offset, reason } => write!(f, "Invalid UTF-8 at byte {}: {}", offset, reason),
36              Error::UnclosedQuote { quote_type, offset } => write!(f, "Unclosed {} quote starting at byte {}", quote_type, offset),
37              Error::InvalidKey { offset, reason } => write!(f, "Invalid key at byte {}: {}", offset, reason),
38              Error::ForbiddenWhitespace { location, offset } => write!(f, "Whitespace not allowed {} at byte {}", location, offset),
39              Error::DoubleEquals { offset } => write!(f, "Double equals sign detected at byte {}. Use quotes: KEY=\"=val\"", offset),
40              Error::InvalidBom { offset } => write!(f, "BOM found at invalid position (byte {})", offset),
41              Error::Expected { offset, expected } => write!(f, "Expected {} at byte {}", expected, offset),
42              Error::Generic { offset, message } => write!(f, "{} at byte {}", message, offset),
43              Error::Io(msg) => write!(f, "IO Error: {}", msg),
44          }
45      }
46  }
47  
48  impl std::error::Error for Error {}