smart-calculator 1.0.3

Natural-language calculator for math, units, time zones, dates, fiat, and crypto conversions
Documentation 
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

use async_trait::async_trait;
use serde::{Deserialize, Serialize};
use serde_json::Value;
use std::{collections::HashMap, error::Error, sync::Arc};

#[derive(Debug, Clone, PartialEq, Serialize, Deserialize)]
#[serde(rename_all = "camelCase")]
pub enum ResultType {
    Math,
    Unit,
    Currency,
    Crypto,
    Time,
    Date,
}

#[derive(Debug, Clone, PartialEq, Serialize, Deserialize)]
#[serde(untagged)]
pub enum AnswerType {
    Number(f64),
    Text(String),
}

#[derive(Debug, Clone, Serialize, Deserialize)]
#[serde(rename_all = "camelCase")]
pub struct CalculatorResult {
    pub res_type: ResultType,
    pub input: String,
    pub result: AnswerType,
    pub formatted: String,

    #[serde(skip_serializing_if = "Option::is_none")]
    pub metadata: Option<HashMap<String, Value>>,
}

#[async_trait]
pub trait RateProvider: Send + Sync {
    async fn get_fiat_rate(
        &self,
        base: &str,
        target: &str,
    ) -> std::result::Result<f64, Box<dyn Error>>;

    async fn get_crypto_rate(
        &self,
        base: &str,
        target: &str,
    ) -> std::result::Result<f64, Box<dyn Error>>;
}

#[derive(Clone, Default)]
pub struct Config {
    rate_provider: Option<Arc<dyn RateProvider + Send + Sync>>,
    timezone: Option<String>,
    locale: Option<String>,
    precision: Option<u8>,
}

impl Config {
    pub fn new() -> Self {
        Self::default()
    }

    pub fn with_rate_provider(
        mut self,
        rate_provider: Arc<dyn RateProvider + Send + Sync>,
    ) -> Self {
        self.rate_provider = Some(rate_provider);
        self
    }

    pub fn with_timezone(mut self, timezone: impl Into<String>) -> Self {
        self.timezone = Some(timezone.into());
        self
    }

    pub fn with_locale(mut self, locale: impl Into<String>) -> Self {
        self.locale = Some(locale.into());
        self
    }

    pub fn with_precision(mut self, precision: u8) -> Self {
        self.precision = Some(precision.clamp(1, 21));
        self
    }

    pub fn rate_provider(&self) -> Option<Arc<dyn RateProvider + Send + Sync>> {
        self.rate_provider.clone()
    }

    pub fn timezone(&self) -> &Option<String> {
        &self.timezone
    }

    pub fn locale(&self) -> &Option<String> {
        &self.locale
    }

    pub fn precision(&self) -> Option<u8> {
        self.precision
    }
}

#[derive(Debug, Clone, PartialEq, Serialize, Deserialize)]
#[serde(tag = "kind", rename_all = "lowercase")]
pub enum Intent {
    Time {
        query: String,
        #[serde(skip_serializing_if = "Option::is_none")]
        from: Option<String>,
        #[serde(skip_serializing_if = "Option::is_none")]
        to: Option<String>,
        #[serde(skip_serializing_if = "Option::is_none")]
        time: Option<String>,
    },

    Date {
        query: String,
    },

    Currency {
        amount: f64,
        from: String,
        to: String,
    },

    Crypto {
        amount: f64,
        from: String,
        to: String,
    },

    Unit {
        amount: f64,
        from: String,
        to: String,
        category: String,
    },

    Math {
        expression: String,
    },
}

#[derive(Debug, Clone, Copy, PartialEq, Eq, Serialize, Deserialize)]
#[serde(rename_all = "lowercase")]
pub enum RelativeDirection {
    Next,
    Last,
    This,
}

impl RelativeDirection {
    pub fn from_str(s: &str) -> Option<Self> {
        match s.to_lowercase().as_str() {
            "next" | "coming" | "upcoming" => Some(Self::Next),
            "last" => Some(Self::Last),
            "this" => Some(Self::This),
            _ => None,
        }
    }
}