//! Functions for console output.
use super::{
    api,
    bt::{BuildTemplate, Traitline},
};
use std::{error::Error, io, io::Write};
use termcolor::{Color, ColorChoice, ColorSpec, StandardStream, WriteColor};

const HEADER_COLOR: Color = Color::Cyan;

/// Format a skill for displaying.
///
/// This is just the skill name (if given).
fn format_skill(skill: &Option<api::Skill>) -> String {
    match *skill {
        None => "none".to_owned(),
        Some(ref skill) => skill.name.to_owned(),
    }
}

/// Format a traitline for displaying.
fn format_traitline(traitline: &Option<Traitline>) -> String {
    match *traitline {
        None => "none".to_owned(),
        Some((ref spec, choices)) => format!(
            "{} - {} - {} - {}",
            spec.name, choices[0], choices[1], choices[2],
        ),
    }
}

/// Show a build template to the standard output stream.
pub fn show_build_template(build: &BuildTemplate) -> io::Result<()> {
    let mut stdout = StandardStream::stdout(ColorChoice::Auto);
    let mut color_spec = ColorSpec::new();
    color_spec.set_fg(Some(HEADER_COLOR));
    color_spec.set_bold(true);

    let mut fields = vec![("Profession:", build.profession().to_string())];

    fields.push(("Skills:", format_skill(&build.skills()[0])));
    for skill in build.skills().iter().skip(1) {
        fields.push(("", format_skill(&skill)));
    }

    fields.push(("Traitlines:", format_traitline(&build.traitlines()[0])));
    for traitline in build.traitlines().iter().skip(1) {
        fields.push(("", format_traitline(&traitline)));
    }

    for (header, field) in &fields {
        stdout.set_color(&color_spec)?;
        write!(stdout, "{:15}", header)?;
        stdout.reset()?;
        writeln!(stdout, "{}", field)?;
    }

    writeln!(stdout)?;
    stdout.set_color(&color_spec)?;
    write!(stdout, "{:15}", "Chat code:")?;
    stdout.reset()?;
    writeln!(stdout, "{}", build.chatlink())?;

    Ok(())
}

/// Show an error to the standard error stream.
///
/// This will also show the chain of errors that lead up to this error, if available.
pub fn show_error<E: Error + ?Sized>(error: &E) -> io::Result<()> {
    let mut error_color = ColorSpec::new();
    error_color.set_fg(Some(Color::Red));
    let mut stderr = StandardStream::stderr(ColorChoice::Auto);

    stderr.set_color(&error_color)?;
    write!(stderr, "[Error]")?;
    stderr.reset()?;
    writeln!(stderr, " {}", error)?;

    let mut source = error.source();
    while let Some(s) = source {
        stderr.set_color(&error_color)?;
        write!(stderr, "  [caused by]")?;
        stderr.reset()?;
        writeln!(stderr, " {}", s)?;

        source = s.source();
    }
    Ok(())
}