logo
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

use super::*;
use serde::de::Error;
use std::result::Result;

impl Serialize for Color {
    fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
    where
        S: Serializer,
    {
        serializer.serialize_u32(u32::from(*self))
    }
}

struct RGBAVisitor;

struct FieldVisitor;

enum RGBAField {
    Red,
    Green,
    Blue,
    Alpha,
}

impl<'de> Visitor<'de> for FieldVisitor {
    type Value = RGBAField;

    fn expecting(&self, formatter: &mut std::fmt::Formatter) -> std::fmt::Result {
        formatter.write_str("`red` or `green` or `blue` or `alpha`")
    }

    fn visit_str<E>(self, value: &str) -> Result<RGBAField, E>
    where
        E: Error,
    {
        match value.to_ascii_lowercase().as_str() {
            "red" | "r" => Ok(RGBAField::Red),
            "green" | "g" => Ok(RGBAField::Green),
            "blue" | "b" => Ok(RGBAField::Blue),
            "alpha" | "a" => Ok(RGBAField::Alpha),
            _ => Err(Error::unknown_field(value, &["red", "green", "blue", "alpha"])),
        }
    }
}

impl<'de> Deserialize<'de> for RGBAField {
    fn deserialize<D>(deserializer: D) -> Result<RGBAField, D::Error>
    where
        D: Deserializer<'de>,
    {
        deserializer.deserialize_identifier(FieldVisitor)
    }
}

impl<'de> Visitor<'de> for RGBAVisitor {
    type Value = Color;

    fn expecting(&self, formatter: &mut Formatter) -> std::fmt::Result {
        formatter.write_str("a hex string or a tuple of three or four integer between 0-255.")
    }

    fn visit_i32<E>(self, v: i32) -> Result<Self::Value, E>
    where
        E: Error,
    {
        Ok(Color::from(v as u32))
    }

    /// used for json
    fn visit_i64<E>(self, v: i64) -> Result<Self::Value, E>
    where
        E: Error,
    {
        Ok(Color::from(v as u32))
    }
    fn visit_u32<E>(self, v: u32) -> Result<Self::Value, E>
    where
        E: Error,
    {
        Ok(Color::from(v))
    }

    fn visit_u64<E>(self, v: u64) -> Result<Self::Value, E>
    where
        E: Error,
    {
        Ok(Color::from(v as u32))
    }

    fn visit_str<E>(self, v: &str) -> Result<Self::Value, E>
    where
        E: Error,
    {
        Color::from_str(v).map_err(|e| Error::custom(e))
    }

    fn visit_bytes<E>(self, v: &[u8]) -> Result<Self::Value, E>
    where
        E: Error,
    {
        match v {
            [r, g, b] => Ok(Color::new(*r, *g, *b, 255)),
            [r, g, b, a] => Ok(Color::new(*r, *g, *b, *a)),
            _ => Err(Error::custom(format!("RGBA must be a tuple of three or four integer between 0-255"))),
        }
    }

    fn visit_newtype_struct<D>(self, deserializer: D) -> Result<Self::Value, D::Error>
    where
        D: Deserializer<'de>,
    {
        let _ = deserializer;
        todo!()
    }

    fn visit_seq<A>(self, seq: A) -> Result<Self::Value, A::Error>
    where
        A: SeqAccess<'de>,
    {
        let _ = seq;
        todo!()
    }

    fn visit_map<A>(self, map: A) -> Result<Self::Value, A::Error>
    where
        A: MapAccess<'de>,
    {
        let _ = map;
        todo!()
    }
}

impl<'de> Deserialize<'de> for Color {
    fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
    where
        D: Deserializer<'de>,
    {
        deserializer.deserialize_any(RGBAVisitor)
    }
}