use std::borrow::ToOwned;
use std::collections::HashMap;
use std::fmt::Write;
use std::io::BufRead;
use std::iter::Iterator;
pub struct Config {
pub column_threshold: usize,
}
const HEADER: &str = r#"
"#;
const FOOTER: &str = "
";
#[derive(PartialEq, Eq, Debug)]
pub struct HTML(String);
impl HTML {
fn escape(value: &str) -> HTML {
let mut escaped: String = String::new();
for c in value.chars() {
match c {
'>' => escaped.push_str(">"),
'<' => escaped.push_str("<"),
'\'' => escaped.push_str("'"),
'"' => escaped.push_str("""),
'&' => escaped.push_str("&"),
ok_c => escaped.push(ok_c),
}
}
HTML(escaped)
}
}
impl From<&str> for HTML {
fn from(value: &str) -> HTML {
HTML(String::from(value))
}
}
impl FromIterator for HTML {
fn from_iter(iter: T) -> HTML
where
T: IntoIterator,
{
HTML(iter.into_iter().map(|html| html.0).collect::())
}
}
impl std::fmt::Display for HTML {
fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
write!(f, "{}", self.0)
}
}
#[derive(Debug, PartialEq, Eq)]
enum InputLine<'a> {
Blank,
RowHeader(&'a str),
Entry(&'a str, Option<&'a str>),
}
impl<'a> From<&'a str> for InputLine<'a> {
fn from(value: &'a str) -> InputLine<'a> {
let trimmed = value.trim_end();
if trimmed.is_empty() {
InputLine::Blank
} else if !trimmed.starts_with(' ') {
InputLine::RowHeader(value.trim())
} else {
match value.split_once(':') {
None => InputLine::Entry(value.trim(), None),
Some((col, instance)) => InputLine::Entry(col.trim(), Some(instance.trim())),
}
}
}
}
#[derive(Debug, PartialEq, Eq)]
struct Row {
label: String,
entries: HashMap>>,
}
struct Reader>> {
input: std::iter::Enumerate,
row: Option,
}
impl>> Reader {
fn new(input: Input) -> Self {
Self {
input: input.enumerate(),
row: None,
}
}
}
impl>> Iterator for Reader {
type Item = Result;
fn next(&mut self) -> Option {
loop {
match self.input.next() {
None => return Ok(std::mem::take(&mut self.row)).transpose(),
Some((_, Err(e))) => return Some(Err(e)),
Some((n, Ok(line))) => match InputLine::from(line.as_ref()) {
InputLine::Blank if self.row.is_some() => {
return Ok(std::mem::take(&mut self.row)).transpose()
}
InputLine::Blank => {}
InputLine::Entry(col, instance) => match &mut self.row {
None => {
return Some(Err(std::io::Error::other(format!(
"{}: Entry with no header",
n + 1
))))
}
Some(ref mut row) => {
row.entries
.entry(col.to_owned())
.and_modify(|is| is.push(instance.map(ToOwned::to_owned)))
.or_insert_with(|| vec![instance.map(ToOwned::to_owned)]);
}
},
InputLine::RowHeader(row) => {
let prev = std::mem::take(&mut self.row);
self.row = Some(Row {
label: row.to_owned(),
entries: HashMap::new(),
});
if prev.is_some() {
return Ok(prev).transpose();
}
}
},
}
}
}
}
fn read_rows(input: impl std::io::Read) -> impl Iterator> {
Reader::new(std::io::BufReader::new(input).lines())
}
fn column_counts(rows: &[Row]) -> Vec<(usize, String)> {
let mut counts: Vec<_> = rows
.iter()
.flat_map(|r| r.entries.keys())
.fold(HashMap::new(), |mut cs, col| {
cs.entry(col.to_owned())
.and_modify(|n| *n += 1)
.or_insert(1);
cs
})
.into_iter()
.map(|(col, n)| (n, col))
.collect();
counts.sort_unstable_by(|(an, acol), (bn, bcol)| bn.cmp(an).then(acol.cmp(bcol)));
counts
}
fn column_order(config: &Config, rows: &[Row]) -> Vec {
column_counts(rows)
.into_iter()
.filter_map(|(n, col)| (n >= config.column_threshold).then_some(col))
.collect()
}
fn render_one_instance(instance: &Option) -> HTML {
match instance {
None => HTML::from("✓"),
Some(instance) => HTML::escape(instance.as_ref()),
}
}
fn render_instances(instances: &[Option]) -> HTML {
let all_empty = instances.iter().all(Option::is_none);
if all_empty && instances.len() == 1 {
HTML::from("")
} else if all_empty {
HTML(format!("{}", instances.len()))
} else {
HTML(
instances
.iter()
.map(render_one_instance)
.map(|html| html.0) // Waiting for slice_concat_trait to stabilize
.collect::>()
.join(" "),
)
}
}
fn render_cell(col: &str, row: &mut Row) -> HTML {
let row_label = HTML::escape(row.label.as_ref());
let col_label = HTML::escape(col);
let instances: Option<&Vec>> = row.entries.get(col);
let class = HTML::from(if instances.is_none() { "" } else { "yes" });
let contents = match instances {
None => HTML::from(""),
Some(is) => render_instances(is),
};
row.entries.remove(col);
HTML(format!(
r#"
{contents}
"#
))
}
fn render_leftover(notcol: &str, instances: &[Option]) -> HTML {
let label = HTML::escape(notcol);
let rest = render_instances(instances);
if rest == HTML::from("") {
HTML(format!("{label}"))
} else {
HTML(format!("{label}: {rest}"))
}
}
fn render_all_leftovers(row: &Row) -> HTML {
let mut order: Vec<_> = row.entries.keys().collect();
order.sort_unstable();
HTML(
order
.into_iter()
.map(|notcol| render_leftover(notcol, row.entries.get(notcol).expect("Key vanished?!")))
.map(|html| html.0) // Waiting for slice_concat_trait to stabilize
.collect::>()
.join(", "),
)
}
fn render_row(columns: &[String], row: &mut Row) -> HTML {
let row_label = HTML::escape(row.label.as_ref());
let cells = columns
.iter()
.map(|col| render_cell(col, row))
.collect::();
let leftovers = render_all_leftovers(row);
HTML(format!(
"