aboutsummaryrefslogtreecommitdiff
path: root/src/meta.rs
blob: 75452c26f9e4ca645704566ecad27426aa5a7ef4 (plain) (blame)
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
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
use std::{borrow::Cow, collections::HashMap, fmt::Display};

/// Structure-ize a Gemini response's meta section into it's mime type and it's
/// parameters.
#[derive(Debug, Default, Clone, PartialEq, Eq)]
pub struct Meta {
  /// The mime type of a Gemini response
  mime:       String,
  /// The parameters of a Gemini response
  parameters: HashMap<String, String>,
}

impl Display for Meta {
  fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
    write!(f, "{}", self.mime)?;

    if !self.parameters.is_empty() {
      write!(f, "; ")?;

      let mut parameters: Vec<_> = self.parameters.iter().collect();

      parameters.sort_by(|a, b| a.0.cmp(b.0));

      for (i, (key, value)) in parameters.iter().enumerate() {
        if i > 0 {
          write!(f, "; ")?;
        }

        write!(f, "{key}={value}")?;
      }
    }

    Ok(())
  }
}

impl Meta {
  /// Create a new `Meta`
  ///
  /// # Example
  ///
  /// ```rust
  /// let mut meta = germ::meta::Meta::new(); 
  /// ```
  #[must_use]
  pub fn new() -> Self { Self::default() }

  /// Create a `Meta` from a string
  ///
  /// # Example
  ///
  /// ```rust
  /// assert_eq!(
  ///   germ::meta::Meta::from_string("text/gemini; hi=2; hi2=string=2").mime(),
  ///   "text/gemini",
  /// );
  /// ```
  #[must_use]
  pub fn from_string<'a>(meta: impl Into<std::borrow::Cow<'a, str>>) -> Self {
    let meta = meta.into().to_string();
    let mut metas = meta.split(';');
    let mime = metas.next().unwrap_or("").to_string();
    let mut parameters = HashMap::new();

    for parameter in metas {
      let trimmed = parameter.trim_start();

      // Only parse parameters containing '=' as those without are malformed
      // according to RFC 2045
      if let Some(equal_pos) = trimmed.find('=') {
        let (key, value) = trimmed.split_at(equal_pos);

        parameters.insert(key.to_string(), value[1..].to_string());
      }
    }

    Self { mime, parameters }
  }

  /// Obtain non-mutable access to the mime of the `Meta`
  ///
  /// # Example
  ///
  /// ```rust
  /// assert_eq!(
  ///   germ::meta::Meta::from_string("text/gemini; hi=2; hi2=string=2").mime(),
  ///   "text/gemini",
  /// );
  /// ```
  #[allow(clippy::missing_const_for_fn)]
  #[must_use]
  pub fn mime(&self) -> Cow<'_, str> { Cow::Borrowed(&self.mime) }

  /// Obtain mutable access to the mime of the `Meta`
  ///
  /// # Example
  ///
  /// ```rust
  /// let mut meta = germ::meta::Meta::new();
  ///
  /// *meta.mime_mut() = "text/gemini".to_string();
  /// ```
  pub const fn mime_mut(&mut self) -> &mut String { &mut self.mime }

  /// Obtain non-mutable access to the parameters of the `Meta`
  ///
  /// # Example
  ///
  /// ```rust
  /// assert_eq!(
  ///   germ::meta::Meta::from_string("text/gemini; hi=2; hi2=string=2")
  ///     .parameters()
  ///     .get("hi2"),
  ///   Some(&"string=2".to_string()),
  /// );
  /// ```
  #[must_use]
  pub const fn parameters(&self) -> &HashMap<String, String> {
    &self.parameters
  }

  /// Obtain mutable access to the parameters of the `Meta`
  ///
  /// # Example
  ///
  /// ```rust
  /// let mut meta = germ::meta::Meta::new();
  /// let mut parameters = std::collections::HashMap::new();
  ///
  /// parameters.insert("hi".to_string(), "2".to_string());
  /// parameters.insert("hi2".to_string(), "string=2".to_string());
  ///
  /// *meta.parameters_mut() = parameters;
  /// ```
  pub const fn parameters_mut(&mut self) -> &mut HashMap<String, String> {
    &mut self.parameters
  }
}