use std::borrow::ToOwned;
use std::collections::HashMap;
use std::fmt::Write;
use std::io::BufRead;
use std::iter::Iterator;
#[derive(PartialEq, Eq, Debug)]
struct Config {
column_threshold: usize,
}
impl Config {
fn apply_command(&mut self, cmd: &str) -> Result<(), std::io::Error> {
if let Some(threshold) = cmd.strip_prefix("col_threshold ") {
self.column_threshold = threshold
.parse()
.map_err(|e| std::io::Error::new(std::io::ErrorKind::InvalidInput, e))?;
}
Ok(())
}
}
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>),
Command(&'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 let Some(cmd) = trimmed.strip_prefix('!') {
InputLine::Command(cmd)
} 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>>,
}
#[derive(Debug, PartialEq, Eq)]
enum Rowlike {
Row(Row),
Spacer,
}
struct Reader<'cfg, Input: Iterator
- >> {
input: std::iter::Enumerate,
row: Option
,
config: &'cfg mut Config,
}
impl<'cfg, Input: Iterator- >> Reader<'cfg, Input> {
fn new(config: &'cfg mut Config, input: Input) -> Self {
Self {
input: input.enumerate(),
row: None,
config,
}
}
}
impl<'cfg, Input: Iterator
- >> Iterator
for Reader<'cfg, Input>
{
type Item = Result;
fn next(&mut self) -> Option {
loop {
match self.input.next() {
None => return Ok(std::mem::take(&mut self.row).map(Rowlike::Row)).transpose(),
Some((_, Err(e))) => return Some(Err(e)),
Some((n, Ok(line))) => match InputLine::from(line.as_ref()) {
InputLine::Command(cmd) => {
if let Err(e) = self.config.apply_command(cmd) {
return Some(Err(e));
}
}
InputLine::Blank if self.row.is_some() => {
return Ok(std::mem::take(&mut self.row).map(Rowlike::Row)).transpose()
}
InputLine::Blank => return Some(Ok(Rowlike::Spacer)),
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.map(Rowlike::Row)).transpose();
}
}
},
}
}
}
}
fn read_input(input: impl std::io::Read) -> Result<(Vec, Config), std::io::Error> {
let mut config = Config {
column_threshold: 2,
};
let reader = Reader::new(&mut config, std::io::BufReader::new(input).lines());
reader
.collect::, _>>()
.map(|rows| (rows, config))
}
fn column_counts(rows: &[Rowlike]) -> Vec<(usize, String)> {
let empty = HashMap::new();
let mut counts: Vec<_> = rows
.iter()
.flat_map(|rl| match rl {
Rowlike::Row(r) => r.entries.keys(),
Rowlike::Spacer => empty.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: &[Rowlike]) -> 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(config: &Config, columns: &[String], rowlike: &mut Rowlike) -> HTML {
match rowlike {
Rowlike::Spacer => HTML::from(" |
|---|
\n"),
Rowlike::Row(row) => {
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!(
"| {row_label} | {cells}{leftovers} |
|---|
\n"
))
}
}
}
fn render_column_headers(config: &Config, columns: &[String]) -> HTML {
HTML(
String::from(r#" | "#)
+ &columns.iter().fold(String::new(), |mut acc, col| {
let col_header = HTML::escape(col.as_ref());
write!(
&mut acc,
r#""#
)
.unwrap();
acc
})
+ "
|---|
\n",
)
}
/// # Errors
///
/// Will return `Err` if
/// * there's an i/o error while reading `input`
/// * the log has invalid syntax:
/// * an indented line with no preceding non-indented line
pub fn tablify(input: impl std::io::Read) -> Result {
let (rows, config) = read_input(input)?;
let columns = column_order(&config, &rows);
Ok(HTML(format!(
"{HEADER}{}{}{FOOTER}",
render_column_headers(&config, &columns),
rows.into_iter()
.map(|mut r| render_row(&config, &columns, &mut r))
.collect::()
)))
}
#[cfg(test)]
mod tests {
use super::*;
#[test]
fn test_parse_line() {
assert_eq!(InputLine::from(""), InputLine::Blank);
assert_eq!(InputLine::from(" "), InputLine::Blank);
assert_eq!(InputLine::from("foo"), InputLine::RowHeader("foo"));
assert_eq!(InputLine::from("foo "), InputLine::RowHeader("foo"));
assert_eq!(InputLine::from(" foo"), InputLine::Entry("foo", None));
assert_eq!(
InputLine::from(" foo:bar"),
InputLine::Entry("foo", Some("bar"))
);
assert_eq!(
InputLine::from(" foo: bar"),
InputLine::Entry("foo", Some("bar"))
);
assert_eq!(
InputLine::from(" foo: bar "),
InputLine::Entry("foo", Some("bar"))
);
assert_eq!(
InputLine::from(" foo: bar "),
InputLine::Entry("foo", Some("bar"))
);
assert_eq!(
InputLine::from(" foo : bar "),
InputLine::Entry("foo", Some("bar"))
);
}
fn read_rows(input: impl std::io::Read) -> Result, std::io::Error> {
read_input(input).map(|(rows, _)| rows)
}
fn read_config(input: impl std::io::Read) -> Result {
read_input(input).map(|(_, config)| config)
}
#[test]
fn test_read_rows() {
assert_eq!(
read_rows(&b"foo"[..]).unwrap(),
vec![Rowlike::Row(Row {
label: "foo".to_owned(),
entries: HashMap::new(),
})]
);
assert_eq!(
read_rows(&b"bar"[..]).unwrap(),
vec![Rowlike::Row(Row {
label: "bar".to_owned(),
entries: HashMap::new(),
})]
);
assert_eq!(
read_rows(&b"foo\nbar\n"[..]).unwrap(),
vec![
Rowlike::Row(Row {
label: "foo".to_owned(),
entries: HashMap::new(),
}),
Rowlike::Row(Row {
label: "bar".to_owned(),
entries: HashMap::new(),
})
]
);
assert_eq!(
read_rows(&b"foo\n bar\n"[..]).unwrap(),
vec![Rowlike::Row(Row {
label: "foo".to_owned(),
entries: HashMap::from([("bar".to_owned(), vec![None])]),
})]
);
assert_eq!(
read_rows(&b"foo\n bar\n baz\n"[..]).unwrap(),
vec![Rowlike::Row(Row {
label: "foo".to_owned(),
entries: HashMap::from([
("bar".to_owned(), vec![None]),
("baz".to_owned(), vec![None])
]),
})]
);
assert_eq!(
read_rows(&b"foo\n\nbar\n"[..]).unwrap(),
vec![
Rowlike::Row(Row {
label: "foo".to_owned(),
entries: HashMap::new(),
}),
Rowlike::Row(Row {
label: "bar".to_owned(),
entries: HashMap::new(),
})
]
);
assert_eq!(
read_rows(&b"foo\n\n\nbar\n"[..]).unwrap(),
vec![
Rowlike::Row(Row {
label: "foo".to_owned(),
entries: HashMap::new(),
}),
Rowlike::Spacer,
Rowlike::Row(Row {
label: "bar".to_owned(),
entries: HashMap::new(),
})
]
);
assert_eq!(
read_rows(&b"foo\n \nbar\n"[..]).unwrap(),
vec![
Rowlike::Row(Row {
label: "foo".to_owned(),
entries: HashMap::new(),
}),
Rowlike::Row(Row {
label: "bar".to_owned(),
entries: HashMap::new(),
})
]
);
assert_eq!(
read_rows(&b"foo \n bar \n"[..]).unwrap(),
vec![Rowlike::Row(Row {
label: "foo".to_owned(),
entries: HashMap::from([("bar".to_owned(), vec![None])]),
})]
);
let bad = read_rows(&b" foo"[..]);
assert!(bad.is_err());
assert!(format!("{bad:?}").contains("1: Entry with no header"));
let bad2 = read_rows(&b"foo\n\n bar"[..]);
assert!(bad2.is_err());
assert!(format!("{bad2:?}").contains("3: Entry with no header"));
}
#[test]
fn test_read_config() {
assert_eq!(
read_config(&b"!col_threshold 10"[..])
.unwrap()
.column_threshold,
10
);
let bad_num = read_config(&b"!col_threshold foo"[..]);
assert!(bad_num.is_err());
assert!(format!("{bad_num:?}").contains("Parse"));
}
#[test]
fn test_column_counts() {
assert_eq!(
column_counts(&read_rows(&b"foo\n bar\n baz\n"[..]).unwrap()),
vec![(1, String::from("bar")), (1, String::from("baz"))]
);
assert_eq!(
column_counts(&read_rows(&b"foo\n bar\n baz\nquux\n baz"[..]).unwrap()),
vec![(2, String::from("baz")), (1, String::from("bar"))]
);
assert_eq!(
column_counts(&read_rows(&b"foo\n bar\n bar\n baz\n bar\nquux\n baz"[..]).unwrap()),
vec![(2, String::from("baz")), (1, String::from("bar"))]
);
assert_eq!(
column_counts(
&read_rows(&b"foo\n bar: 1\n bar: 2\n baz\n bar\nquux\n baz"[..]).unwrap()
),
vec![(2, String::from("baz")), (1, String::from("bar"))]
);
}
#[test]
fn test_render_cell() {
assert_eq!(
render_cell(
"foo",
&mut Row {
label: "nope".to_owned(),
entries: HashMap::new(),
}
),
HTML::from(
r#" | "#
)
);
assert_eq!(
render_cell(
"foo",
&mut Row {
label: "nope".to_owned(),
entries: HashMap::from([("bar".to_owned(), vec![None])]),
}
),
HTML::from(
r#" | "#
)
);
assert_eq!(
render_cell(
"foo",
&mut Row {
label: "nope".to_owned(),
entries: HashMap::from([("foo".to_owned(), vec![None])]),
}
),
HTML::from(
r#" | "#
)
);
assert_eq!(
render_cell(
"foo",
&mut Row {
label: "nope".to_owned(),
entries: HashMap::from([("foo".to_owned(), vec![None, None])]),
}
),
HTML::from(
r#"2 | "#
)
);
assert_eq!(
render_cell(
"foo",
&mut Row {
label: "nope".to_owned(),
entries: HashMap::from([(
"foo".to_owned(),
vec![Some("5".to_owned()), Some("10".to_owned())]
)]),
}
),
HTML::from(
r#"5 10 | "#
)
);
assert_eq!(
render_cell(
"foo",
&mut Row {
label: "nope".to_owned(),
entries: HashMap::from([("foo".to_owned(), vec![Some("5".to_owned()), None])]),
}
),
HTML::from(
r#"5 ✓ | "#
)
);
assert_eq!(
render_cell(
"heart",
&mut Row {
label: "nope".to_owned(),
entries: HashMap::from([("heart".to_owned(), vec![Some("<3".to_owned())])]),
}
),
HTML::from(
r#"<3 | "#
)
);
assert_eq!(
render_cell(
"foo",
&mut Row {
label: "bob's".to_owned(),
entries: HashMap::from([("foo".to_owned(), vec![None])]),
}
),
HTML::from(
r#" | "#
)
);
let mut r = Row {
label: "nope".to_owned(),
entries: HashMap::from([
("foo".to_owned(), vec![None]),
("baz".to_owned(), vec![None]),
]),
};
assert_eq!(r.entries.len(), 2);
render_cell("foo", &mut r);
assert_eq!(r.entries.len(), 1);
render_cell("bar", &mut r);
assert_eq!(r.entries.len(), 1);
render_cell("baz", &mut r);
assert_eq!(r.entries.len(), 0);
}
#[test]
fn test_render_leftovers() {
assert_eq!(
render_all_leftovers(&Row {
label: "nope".to_owned(),
entries: HashMap::from([("foo".to_owned(), vec![None])]),
}),
HTML::from("foo")
);
assert_eq!(
render_all_leftovers(&Row {
label: "nope".to_owned(),
entries: HashMap::from([
("foo".to_owned(), vec![None]),
("bar".to_owned(), vec![None])
]),
}),
HTML::from("bar, foo")
);
assert_eq!(
render_all_leftovers(&Row {
label: "nope".to_owned(),
entries: HashMap::from([
("foo".to_owned(), vec![None]),
("bar".to_owned(), vec![None, None])
]),
}),
HTML::from("bar: 2, foo")
);
}
#[test]
fn test_render_row() {
assert_eq!(
render_row(
&Config {
column_threshold: 0,
},
&["foo".to_owned()],
&mut Rowlike::Row(Row {
label: "nope".to_owned(),
entries: HashMap::from([("bar".to_owned(), vec![None])]),
})
),
HTML::from(
r#"| nope | | bar |
|---|
"#
)
);
}
}