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use console::style;
use dialoguer::{theme::ColorfulTheme, Input, Select};
use temp_converter::*;
use thousands::Separable;
fn main() -> std::io::Result<()> {
// Define the possible choices of temperature units
let items = vec!["Celsius", "Fahrenheit", "Kelvin"];
// User prompt for selecting the initial temperature unit
let from = Select::with_theme(&ColorfulTheme::default())
.with_prompt("What unit do you want to convert from?")
.clear(true)
.report(true)
.items(&items)
.default(0)
.interact_opt()?;
if from.is_none() {
println!("Goodbye!");
return Ok(());
}
// User prompt for the output temperature unit
let to = Select::with_theme(&ColorfulTheme::default())
.with_prompt("What unit do you want to convert it into?")
.clear(true)
.report(true)
.items(&items)
.default(0)
.interact_opt()?;
if to.is_none() {
println!("Goodbye!");
return Ok(());
}
// Initial value prompt
let input: String = Input::with_theme(&ColorfulTheme::default())
.with_prompt("Please write the value")
.report(true)
.validate_with(|input: &String| -> Result<(), &str> {
if input.parse::<f32>().is_ok() {
Ok(())
} else {
Err("Please input a valid number")
}
})
.interact_text()?;
// Convert the input string to a floating point number,
// unwrapping fearlessly because the input has already been validated
let input_number: f32 = input.parse().unwrap();
let result: f32;
// Stack allocated buffer for result formatting
let mut output = String::new();
// Match all possible choices, using the corresponding function on each one
if let Some(from_index) = from {
if let Some(to_index) = to {
match from_index {
0 => {
if to_index == 1 {
result = celsius_to_fahrenheit(input_number);
output = format!(
"{} {} °F",
style("Result:").green(),
result.separate_with_commas()
);
} else if to_index == 2 {
result = celsius_to_kelvin(input_number);
output = format!(
"{} {} K",
style("Result:").green(),
result.separate_with_commas()
);
} else {
result = input_number;
output = format!(
"{} {} °C",
style("Result:").green(),
result.separate_with_commas()
);
}
}
1 => {
if to_index == 0 {
result = fahrenheit_to_celsius(input_number);
output = format!(
"{} {} °C",
style("Result:").green(),
result.separate_with_commas()
);
} else if to_index == 2 {
result = fahrenheit_to_kelvin(input_number);
output = format!(
"{} {} K",
style("Result:").green(),
result.separate_with_commas()
);
} else {
result = input_number;
output = format!(
"{} {} °F",
style("Result:").green(),
result.separate_with_commas()
);
}
}
2 => {
if to_index == 0 {
result = kelvin_to_celsius(input_number);
output = format!(
"{} {} °C",
style("Result:").green(),
result.separate_with_commas()
);
} else if to_index == 1 {
result = kelvin_to_fahrenheit(input_number);
output = format!(
"{} {} °F",
style("Result:").green(),
result.separate_with_commas()
);
} else {
result = input_number;
output = format!(
"{} {} K",
style("Result:").green(),
result.separate_with_commas()
);
}
}
_ => {}
}
}
}
println!("{output}");
Ok(())
}