use crate::validators::InputValueValidator;
use crate::Value;

/// List minimum length validator
pub struct ListMinLength {
    /// Must be greater than or equal to this value.
    pub length: i32,
}

impl InputValueValidator for ListMinLength {
    fn is_valid(&self, value: &Value) -> Result<(), String> {
        if let Value::List(values) = value {
            if values.len() < self.length as usize {
                Err(format!(
                    "the value length is {}, must be greater than or equal to {}",
                    values.len(),
                    self.length
                ))
            } else {
                Ok(())
            }
        } else {
            Ok(())
        }
    }
}

/// List maximum length validator
pub struct ListMaxLength {
    /// Must be less than or equal to this value.
    pub length: i32,
}

impl InputValueValidator for ListMaxLength {
    fn is_valid(&self, value: &Value) -> Result<(), String> {
        if let Value::List(values) = value {
            if values.len() > self.length as usize {
                Err(format!(
                    "the value length is {}, must be less than or equal to {}",
                    values.len(),
                    self.length
                ))
            } else {
                Ok(())
            }
        } else {
            Ok(())
        }
    }
}

#[doc(hidden)]
pub struct List<T>(pub T);

impl<T: InputValueValidator> InputValueValidator for List<T> {
    fn is_valid(&self, value: &Value) -> Result<(), String> {
        if let Value::List(elems) = value {
            for elem in elems {
                self.0.is_valid(elem)?;
            }
        }
        Ok(())
    }
}