use crate::data::{AccountName, Hoard, Transaction, TransactionRef};

#[derive(Clone, Copy, Default)]
#[allow(unused)]
pub enum Align {
    #[default]
    Left,
    Centre,
    Right,
}

#[derive(Clone, Default)]
pub struct Column {
    pub align: Align,
    pub left_border: bool,
    pub right_border: bool,
}

pub enum Row {
    Line,
    Data(Vec<String>),
}

pub fn show_table(cols: Vec<Column>, rows: impl Iterator<Item = Row>) {
    let mut min_widths = vec![0usize; cols.len()];

    let table_data = rows.collect::<Vec<_>>();
    for row in &table_data {
        let Row::Data(row) = &row else { continue };
        for (idx, rc) in row.iter().enumerate() {
            min_widths[idx] = min_widths[idx].max(console::measure_text_width(rc.as_str()));
        }
    }

    for row in table_data {
        match row {
            Row::Line => {
                for (idx, col) in min_widths.iter().enumerate() {
                    if cols[idx].left_border {
                        print!("{}", boxy::Char::cross(boxy::Weight::Normal));
                    }
                    for _ in 0..=*col {
                        print!("{}", boxy::Char::horizontal(boxy::Weight::Normal));
                    }
                    if cols[idx].right_border {
                        print!("{}", boxy::Char::cross(boxy::Weight::Normal));
                    }
                }
            }
            Row::Data(row) => {
                for (idx, col) in row.into_iter().enumerate() {
                    if cols[idx].left_border {
                        print!("{}", boxy::Char::vertical(boxy::Weight::Normal));
                    }
                    match cols[idx].align {
                        Align::Left => print!("{col:<width$}", width = min_widths[idx] + 1),
                        Align::Centre => print!("{col:^width$}", width = min_widths[idx] + 1),
                        Align::Right => print!("{col:>width$}", width = min_widths[idx] + 1),
                    }
                    if cols[idx].right_border {
                        print!("{}", boxy::Char::vertical(boxy::Weight::Normal));
                    }
                }
            }
        }
        println!();
    }
}

pub fn show_transaction(_root: Option<&Hoard>, txn: &Transaction) {
    let bluestyle = console::Style::new().blue();
    // let greenstyle = console::Style::new().green();
    let yellowstyle = console::Style::new().yellow();
    let graystyle = console::Style::new().white().dim();
    println!(
        "{}: {}",
        bluestyle.apply_to(txn.datestamp),
        txn.title.as_deref().unwrap_or("")
    );
    for change in &txn.changes {
        println!(
            " - {}: {} {}",
            yellowstyle.apply_to(change.account),
            change.amount,
            graystyle.apply_to(change.unit)
        );
    }
}

#[derive(Clone, Copy, Default)]
pub struct TransactionTable {}

impl TransactionTable {
    fn make_columns(&self) -> Vec<Column> {
        vec![
            // datestamp
            Column {
                align: Align::Left,
                right_border: true,
                ..Default::default()
            },
            // Memo
            Column {
                align: Align::Left,
                ..Default::default()
            },
            // Amount
            Column {
                align: Align::Right,
                ..Default::default()
            },
            // Balance
            Column {
                align: Align::Right,
                left_border: true,
                ..Default::default()
            },
        ]
    }

    fn make_header_row(&self) -> Row {
        Row::Data(vec![
            "Date".into(),
            "Memo".into(),
            "Amount".into(),
            "Balance".into(),
        ])
    }

    fn format_txn(
        &self,
        root: Option<&Hoard>,
        account: AccountName,
        txn: &Transaction,
    ) -> Option<Row> {
        let Some(chg) = txn.change_for(account) else {
            return None;
        };
        let precision = root
            .and_then(|r| r.unit_spec(*chg.unit))
            .and_then(|v| v.precision)
            .unwrap_or(2) as usize;
        Some(Row::Data(vec![
            txn.datestamp.to_string(),
            txn.title.clone().unwrap_or_else(String::new),
            format!("{:.precision$}", chg.amount),
            chg.balance
                .as_deref()
                .map(|b| format!("{:.precision$}", b))
                .unwrap_or(String::new()),
        ]))
    }

    pub fn show<'d>(
        self,
        root: Option<&Hoard>,
        account: AccountName,
        txns: impl Iterator<Item = &'d Transaction>,
    ) {
        show_table(
            self.make_columns(),
            vec![self.make_header_row(), Row::Line]
                .into_iter()
                .chain(txns.filter_map(|txn| self.format_txn(root, account, txn))),
        )
    }

    pub fn show_refs<'d>(
        self,
        root: Option<&Hoard>,
        account: AccountName,
        txns: impl Iterator<Item = &'d TransactionRef>,
    ) {
        show_table(
            self.make_columns(),
            vec![self.make_header_row(), Row::Line]
                .into_iter()
                .chain(txns.filter_map(|txn| self.format_txn(root, account, &txn.borrow()))),
        )
    }
}