use super::{AccountName, UnitName, Spanned};

mod parse;
pub use parse::parse_ledger;

mod print;
pub use print::print_ledger;

#[derive(Clone, Debug, PartialEq, PartialOrd, Ord, Eq)]
pub struct Balance {
    pub account: Spanned<AccountName>,
    pub amount: Spanned<rust_decimal::Decimal>,
    pub unit: Spanned<UnitName>,
}

#[derive(Clone, Debug, PartialEq, PartialOrd, Eq, Ord)]
pub struct LedgerEntry {
    pub datestamp: (u16, u8, u8),
    pub title: Option<String>,
    pub balances: Vec<Spanned<Balance>>,
}

impl LedgerEntry {
    pub fn modifies(&self, account: AccountName) -> bool {
        self.balances.iter().any(|b| b.account.as_ref() == &account)
    }

    pub fn balance_for(&self, account: AccountName) -> Option<&Spanned<Balance>> {
        self.balances.iter().find(|b| b.account.as_ref() == &account)
    }

    pub fn split_balances(
        &self,
        account: AccountName,
    ) -> Option<(&Spanned<Balance>, impl Iterator<Item = &Spanned<Balance>>)> {
        let index = self.balances.iter().position(|b| b.account.as_ref() == &account)?;
        Some((
            &self.balances[index],
            self.balances[0..index]
                .iter()
                .chain(self.balances[index + 1..].iter()),
        ))
    }
}