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
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198

use anyhow::{bail, Error, Result};
use bc_components::tags;
use dcbor::prelude::*;

use crate::{string_utils::StringUtils, Envelope, EnvelopeEncodable};

use super::FunctionsStore;

#[derive(Clone, Debug, Eq)]
pub enum FunctionName {
    Static(&'static str),
    Dynamic(String),
}

impl FunctionName {
    fn value(&self) -> &str {
        match self {
            Self::Static(name) => name,
            Self::Dynamic(name) => name,
        }
    }
}

impl PartialEq for FunctionName {
    fn eq(&self, other: &Self) -> bool {
        self.value() == other.value()
    }
}

impl std::hash::Hash for FunctionName {
    fn hash<H: std::hash::Hasher>(&self, state: &mut H) {
        self.value().hash(state)
    }
}

/// A declared function.
 #[derive(Debug, Clone, Eq)]
pub enum Function {
    Known(u64, Option<FunctionName>),
    Named(FunctionName),
}

impl Function {
    /// Creates a new function with a value and an optional name.
    pub fn new_known(value: u64, name: Option<String>) -> Self {
        Self::Known(value, name.map(FunctionName::Dynamic))
    }

    /// Creates a new function with a name. This call cannot be used
    /// to declare a function at compile-time.
    pub fn new_named(name: &str) -> Self {
        Self::Named(FunctionName::Dynamic(name.into()))
    }

    /// Creates a new function with a value and a static name.
    /// This call can be used to declare a function at compile-time.
    pub const fn new_with_static_name(value: u64, name: &'static str) -> Self {
        Self::Known(value, Some(FunctionName::Static(name)))
    }

    /// Creates a new function with a static name.
    /// This call can be used to declare a function at compile-time.
    pub const fn new_static_named(name: &'static str) -> Self {
        Self::Named(FunctionName::Static(name))
    }

    /// Returns the name of the function.
    pub fn name(&self) -> String {
        match self {
            Self::Known(value, name) => {
                if let Some(name) = name {
                    name.value().to_string()
                } else {
                    value.to_string()
                }
            },
            Self::Named(name) => name.value().to_string().flanked_by("\"", "\""),
        }
    }

    /// Returns the name of the named function, if any.
    pub fn named_name(&self) -> Option<String> {
        match self {
            Self::Known(_, _) => None,
            Self::Named(name) => Some(name.value().to_string()),
        }
    }

}

impl PartialEq for Function {
    fn eq(&self, other: &Self) -> bool {
        match (self, other) {
            (Function::Known(l, _), Function::Known(r, _)) => l == r,
            (Function::Named(l), Function::Named(r)) => l == r,
            _ => false,
        }
    }
}

impl std::hash::Hash for Function {
    fn hash<H: std::hash::Hasher>(&self, state: &mut H) {
        match self {
            Function::Known(value, _) => value.hash(state),
            Function::Named(name) => name.hash(state),
        }
    }
}

impl From<u64> for Function {
    fn from(value: u64) -> Self {
        Self::new_known(value, None)
    }
}

impl From<&str> for Function {
    fn from(name: &str) -> Self {
        Self::new_named(name)
    }
}

impl From<&Function> for Function {
    fn from(function: &Function) -> Self {
        function.clone()
    }
}

impl CBORTagged for Function {
    fn cbor_tags() -> Vec<Tag> {
        vec![tags::FUNCTION]
    }
}

impl From<Function> for CBOR {
    fn from(value: Function) -> Self {
        value.tagged_cbor()
    }
}

impl CBORTaggedEncodable for Function {
    fn untagged_cbor(&self) -> CBOR {
        match self {
            Function::Known(value, _) => (*value).into(),
            Function::Named(name) => name.value().into(),
        }
    }
}

impl TryFrom<CBOR> for Function {
    type Error = Error;

    fn try_from(cbor: CBOR) -> Result<Self> {
        Self::from_tagged_cbor(cbor)
    }
}

impl CBORTaggedDecodable for Function {
    fn from_untagged_cbor(untagged_cbor: CBOR) -> Result<Self> {
        match untagged_cbor.as_case() {
            CBORCase::Unsigned(value) => Ok(Self::new_known(*value, None)),
            CBORCase::Text(name) => Ok(Self::new_named(name)),
            _ => bail!("invalid function"),
        }
    }
}

impl Function {
    fn description(&self, functions: Option<&FunctionsStore>) -> String {
        match self {
            Function::Known(_, _) => {
                FunctionsStore::name_for_function(self, functions)
            },
            Function::Named(name) => {
                format!("\"{}\"", name.value())
            },
        }
    }
}

impl std::fmt::Display for Function {
    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
        write!(f, "{}", self.description(None))
    }
}

impl EnvelopeEncodable for Function {
    fn into_envelope(self) -> Envelope {
        Envelope::new_leaf(self)
    }
}

impl TryFrom<Envelope> for Function {
    type Error = Error;

    fn try_from(envelope: Envelope) -> Result<Self> {
        Function::try_from(envelope.try_leaf()?)
    }
}