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

/*
 * smartcalc v1.0.8
 * Copyright (c) Erhan BARIS (Ruslan Ognyanov Asenov)
 * Licensed under the GNU General Public License v2.0.
 */

use core::any::Any;
use core::any::TypeId;
use core::ops::Deref;

use alloc::rc::Rc;
use alloc::string::String;
use alloc::string::ToString;
use alloc::format;

use crate::session::Session;
use crate::config::SmartCalcConfig;
use crate::types::*;
use crate::variable::VariableInfo;

pub mod number;
pub mod percent;
pub mod money;
pub mod time;
pub mod duration;
pub mod date;
pub mod date_time;
pub mod dynamic_type;

#[derive(Clone)]
#[derive(Copy)]
pub enum OperationType {
    Add,
    Div,
    Mul,
    Sub
}


#[derive(Clone)]
#[derive(Copy)]
pub enum UnaryType {
    Plus,
    Minus
}

pub trait DataItem: alloc::fmt::Debug {
    fn unary(&self, unary: UnaryType) -> Rc<dyn DataItem>;
    fn is_same(&self, other: &dyn Any) -> bool;
    fn as_token_type(&self) -> TokenType;
    fn as_any(&self) -> &dyn Any;
    fn get_number(&self, other: &dyn DataItem) -> f64;
    fn get_underlying_number(&self) -> f64;
    fn type_name(&self) -> &'static str;
    fn type_id(&self) -> TypeId;
    fn calculate(&self, config: &SmartCalcConfig, on_left: bool, other: &dyn DataItem, operation_type: OperationType) -> Option<Rc<dyn DataItem>>;
    fn print(&self, config: &SmartCalcConfig, session: &Session) -> String;
}

pub struct Interpreter;

impl Interpreter {
    pub fn execute(config: &SmartCalcConfig, ast: Rc<SmartCalcAstType>, session: &Session) -> Result<Rc<SmartCalcAstType>, String> {
        Interpreter::execute_ast(config, session, ast)
    }

    fn execute_ast(config: &SmartCalcConfig, session: &Session, ast: Rc<SmartCalcAstType>) -> Result<Rc<SmartCalcAstType>, String> {
        match ast.deref() {
            SmartCalcAstType::Binary { left, operator, right } => Interpreter::executer_binary(config, session, left.clone(), *operator, right.clone()),
            SmartCalcAstType::Assignment { variable, expression } => Interpreter::executer_assignment(config, session, variable.clone(), expression.clone()),
            SmartCalcAstType::Variable(variable)               => Ok(Interpreter::executer_variable(variable.clone())),
            SmartCalcAstType::Item(_)                          => Ok(ast),
            SmartCalcAstType::Month(_)                         => Ok(ast),
            SmartCalcAstType::PrefixUnary(ch, ast)             => Interpreter::executer_unary(config, session, *ch, ast.clone()),
            SmartCalcAstType::None                             => Ok(Rc::new(SmartCalcAstType::None)),
            _ => {
                log::debug!("Operation not implemented {:?}", ast);
                Ok(Rc::new(SmartCalcAstType::None))
            }
        }
    }

    fn executer_variable(variable: Rc<VariableInfo>) -> Rc<SmartCalcAstType> {
        variable.data.borrow().clone()
    }

    fn executer_assignment(config: &SmartCalcConfig, session: &Session, variable: Rc<VariableInfo>, expression: Rc<SmartCalcAstType>) -> Result<Rc<SmartCalcAstType>, String> {
        let computed  = Interpreter::execute_ast(config, session, expression)?;
        *variable.data.borrow_mut() = computed.clone();
        Ok(computed)
    }
    
    fn calculate_item(config: &SmartCalcConfig, operator: char, left: Rc<SmartCalcAstType>, right: Rc<SmartCalcAstType>) -> Result<Rc<SmartCalcAstType>, String> {
        let left = match left.deref() {
            SmartCalcAstType::Item(left) => left.clone(),
            _ => return Err("Unknown calculation".to_string())
        };
        
        let right = match right.deref() {
            SmartCalcAstType::Item(right) => right.clone(),
            _ => return Err("Unknown calculation".to_string())
        };
        
        let result = match operator {
            '+' => left.calculate(config, true, right.deref(), OperationType::Add),
            '-' => left.calculate(config, true, right.deref(), OperationType::Sub),
            '*' => left.calculate(config, true, right.deref(), OperationType::Mul),
            '/' => left.calculate(config, true, right.deref(), OperationType::Div),
            _ => return Err(format!("Unknown operator. ({})", operator))
        };
        
        match result {
            Some(item) => Ok(Rc::new(SmartCalcAstType::Item(item.clone()))),
            None => Err("Unknown calculation".to_string())
        }
    }

    fn executer_binary(config: &SmartCalcConfig, session: &Session, left: Rc<SmartCalcAstType>, operator: char, right: Rc<SmartCalcAstType>) -> Result<Rc<SmartCalcAstType>, String> {
        let computed_left  = Interpreter::execute_ast(config, session, left)?;
        let computed_right = Interpreter::execute_ast(config, session, right)?;

        match (computed_left.deref(), computed_right.deref()) {
            (SmartCalcAstType::Item(_), _)           | (_, SmartCalcAstType::Item(_))           => Interpreter::calculate_item(config, operator, computed_left.clone(), computed_right.clone()),
            _ => Err("Uknown calculation result".to_string())
        }
    }

    fn executer_unary(config: &SmartCalcConfig, session: &Session, operator: char, ast: Rc<SmartCalcAstType>) -> Result<Rc<SmartCalcAstType>, String> {
        let computed = Interpreter::execute_ast(config, session, ast)?;

        let result = match operator {
            '+' => return Ok(computed),
            '-' => match computed.deref() {
                SmartCalcAstType::Item(item) => SmartCalcAstType::Item(item.unary(UnaryType::Minus)),
                _ => return Err("Syntax error".to_string())
            },
            _ => return Err("Syntax error".to_string())
        };

        Ok(Rc::new(result))
    }
}