ocpi_tariffs_cli/

print.rs

use std::fmt::{self, Write as _};

use console::{measure_text_width, style};
use ocpi_tariffs::UnknownFields;
use tracing::error;

/// A general purpose horizontal break
const LINE: &str = "----------------------------------------------------------------";
/// The initial amount of memory allocated for writing out the table.
const TABLE_BUF_LEN: usize = 4096;

/// Print the unknown fields of a CDR to stderr.
pub fn unknown_cdr_fields(unknown_fields: UnknownFields) {
    if unknown_fields.is_empty() {
        return;
    }

    eprintln!(
        "{}: {} Unknown fields found in the CDR",
        style("WARN").yellow(),
        unknown_fields.len(),
    );

    for field_name in unknown_fields {
        eprintln!("  - {}", style(field_name).yellow());
    }

    let line = style(LINE).yellow();
    eprintln!("{line}");
}

/// Print the unknown fields of a list of tariffs to stderr.
pub fn unknown_tariff_fields(unknown_fields: Vec<(String, UnknownFields)>) {
    if unknown_fields
        .iter()
        .all(|(_, unknown_fields)| unknown_fields.is_empty())
    {
        return;
    }

    let line = style(LINE).yellow();

    eprintln!(
        "{}: Unknown fields found in the tariffs",
        style("WARN").yellow(),
    );

    for (tariff_id, unknown_fields) in unknown_fields {
        if unknown_fields.is_empty() {
            continue;
        }

        eprintln!(
            "{}: {} Unknown fields found in the tariff with id: {}",
            style("WARN").yellow(),
            unknown_fields.len(),
            style(tariff_id).yellow(),
        );

        for field_name in unknown_fields {
            eprintln!("  - {}", style(field_name).yellow());
        }

        eprintln!("{line}");
    }

    eprintln!("{line}");
}

/// A helper for printing tables with fixed width cols.
pub struct Table {
    /// The widths given in the `header` fn.
    widths: Vec<usize>,
    /// The table is written into this buffer.
    buf: String,
}

/// The config date for setting up a table column.
pub struct Col<'a> {
    pub label: &'a dyn fmt::Display,
    pub width: usize,
}

impl Col<'_> {
    pub fn empty(width: usize) -> Self {
        Self { label: &"", width }
    }
}

impl Table {
    /// Print the table header and use the column widths for all the following rows.
    pub fn header(header: &[Col<'_>]) -> Self {
        let widths = header
            .iter()
            .map(|Col { label: _, width }| *width)
            .collect::<Vec<_>>();
        let mut buf = String::with_capacity(TABLE_BUF_LEN);
        let labels = header
            .iter()
            .map(|Col { label, width: _ }| *label)
            .collect::<Vec<_>>();

        print_table_line(&mut buf, &widths);
        print_table_row(&mut buf, &widths, &labels);
        print_table_line(&mut buf, &widths);

        Self { widths, buf }
    }

    /// Print a separating line.
    pub fn print_line(&mut self) {
        print_table_line(&mut self.buf, &self.widths);
    }

    /// Print a single row of values.
    pub fn print_row(&mut self, values: &[&dyn fmt::Display]) {
        print_table_row(&mut self.buf, &self.widths, values);
    }

    /// Print a single row with a label stylized based of the validity.
    ///
    /// If the row represents a valid value, the label is colored green.
    /// Otherwise the label is colored red.
    pub fn print_valid_row(
        &mut self,
        is_valid: bool,
        label: &'static str,
        values: &[&dyn fmt::Display],
    ) {
        let label = if is_valid {
            style(label).green()
        } else {
            style(label).red()
        };
        print_table_row_with_label(&mut self.buf, &self.widths, &label, values);
    }

    /// Print the bottom line of the table and return the buffer for printing.
    pub fn finish(self) -> String {
        let Self { widths, mut buf } = self;
        print_table_line(&mut buf, &widths);
        buf
    }
}

/// Just like the std lib `write!` macro except that it suppresses in `fmt::Result`.
///
/// This should only be used if you are in control of the buffer you're writing to
/// and the only way it can fail is if the OS allocator fails.
///
/// See: <https://doc.rust-lang.org/std/io/trait.Write.html#method.write_fmt>
#[macro_export]
macro_rules! write_or {
    ($dst:expr, $($arg:tt)*) => {{
        let _ignore_result = $dst.write_fmt(std::format_args!($($arg)*));
    }};
}

/// Print a separation line for a table.
fn print_table_line(buf: &mut String, widths: &[usize]) {
    write_or!(buf, "+");

    for width in widths {
        write_or!(buf, "{0:->1$}+", "", width + 2);
    }

    write_or!(buf, "\n");
}

/// Print a single row to the buffer with a label.
fn print_table_row(buf: &mut String, widths: &[usize], values: &[&dyn fmt::Display]) {
    assert_eq!(
        widths.len(),
        values.len(),
        "The widths and values amounts should be the same"
    );
    print_table_row_(buf, widths, values, None);
}

/// Print a single row to the buffer with a distinct label.
///
/// This fn is used to create a row with a stylized label.
fn print_table_row_with_label(
    buf: &mut String,
    widths: &[usize],
    label: &dyn fmt::Display,
    values: &[&dyn fmt::Display],
) {
    print_table_row_(buf, widths, values, Some(label));
}

/// Print a single row to the buffer.
fn print_table_row_(
    buf: &mut String,
    widths: &[usize],
    values: &[&dyn fmt::Display],
    label: Option<&dyn fmt::Display>,
) {
    write_or!(buf, "|");

    if let Some(label) = label {
        let mut widths = widths.iter();
        let Some(width) = widths.next() else {
            return;
        };
        print_col(buf, label, *width);

        for (value, width) in values.iter().zip(widths) {
            print_col(buf, *value, *width);
        }
    } else {
        for (value, width) in values.iter().zip(widths) {
            print_col(buf, *value, *width);
        }
    }

    write_or!(buf, "\n");
}

/// Print a single column to the buffer
fn print_col(buf: &mut String, value: &dyn fmt::Display, width: usize) {
    write_or!(buf, " ");

    // The value could contain ANSI escape codes and the `Display` impl of the type
    // may not implement fill and alignment logic. So we need to implement left-aligned text ourselves.
    let len_before = buf.len();
    write_or!(buf, "{value}");
    let len_after = buf.len();

    // Use the len before and after to capture the str just written.
    // And compute it's visible len in the terminal.
    let Some(s) = &buf.get(len_before..len_after) else {
        error!("Non UTF8 values were written as a column value");
        return;
    };

    let len = measure_text_width(s);
    // calculate the padding we need to apply at the end of the str.
    let padding = width.saturating_sub(len);

    // and apply the padding
    for _ in 0..padding {
        write_or!(buf, " ");
    }

    write_or!(buf, " |");
}