use std::collections::{HashMap, HashSet};
use std::io::BufRead;
use std::iter::Iterator;
const HEADER: &str = "
";
const FOOTER: &str = "
";
#[derive(Debug, PartialEq, Eq, Hash)]
struct Entry {
col: String,
instance: Option,
}
impl From<&str> for Entry {
fn from(value: &str) -> Entry {
match value.split_once(':') {
None => Entry {
col: String::from(value),
instance: None,
},
Some((col, instance)) => Entry {
col: String::from(col.trim()),
instance: Some(String::from(instance.trim())),
},
}
}
}
#[derive(Debug, PartialEq, Eq)]
struct RowInput {
label: String,
entries: Vec,
}
struct Reader>> {
input: std::iter::Enumerate,
}
impl>> Reader>> Iterator for Reader;
fn next(&mut self) -> Option {
loop {
match self
.input
.next()
.map(|(n, r)| (n, r.map(|line| String::from(line.trim_end()))))
{
None => return Ok(std::mem::take(&mut self.row)).transpose(),
Some((_, Err(e))) => return Some(Err(e)),
Some((_, Ok(line))) if line.is_empty() && self.row.is_some() => {
return Ok(std::mem::take(&mut self.row)).transpose()
}
Some((_, Ok(line))) if line.is_empty() => {}
Some((n, Ok(line))) if line.starts_with(' ') => 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.push(Entry::from(line.trim())),
},
Some((_, Ok(line))) => {
let prev = std::mem::take(&mut self.row);
self.row = Some(RowInput {
label: line,
entries: vec![],
});
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: &[RowInput]) -> Vec<(usize, String)> {
let mut counts: Vec<_> = rows
.iter()
.flat_map(|r| {
r.entries
.iter()
.map(|e| &e.col)
.collect::
>()
.into_iter()
})
.fold(HashMap::new(), |mut cs, col| {
cs.entry(String::from(col))
.and_modify(|n| *n += 1)
.or_insert(1);
cs
})
.into_iter()
.map(|(col, n)| (n, col))
.collect();
counts.sort();
counts
}
fn column_order(rows: &[RowInput]) -> Vec {
column_counts(rows)
.into_iter()
.map(|(_, col)| col)
.collect()
}
fn render_instance(entry: &Entry) -> String {
match &entry.instance {
None => String::from("✓ "),
Some(instance) => String::from(instance) + " ",
}
}
fn render_cell(col: &str, row: &RowInput) -> String {
// TODO: Escape HTML special characters
let entries: Vec<&Entry> = row.entries.iter().filter(|e| e.col == col).collect();
let class = if entries.is_empty() { "" } else { "yes" };
let all_empty = entries.iter().all(|e| e.instance.is_none());
let contents = if entries.is_empty() || (all_empty && entries.len() == 1) {
String::new()
} else if all_empty {
format!("{}", entries.len())
} else {
entries
.iter()
.map(|i| render_instance(i))
.collect::()
};
format!("{} ", contents.trim())
}
fn render_row(columns: &[String], row: &RowInput) -> String {
// This is O(n^2) & doesn't need to be
// TODO: Escape HTML special characters
format!(
"{} {}()
)
}
fn render_column_headers(columns: &[String]) -> String {
// TODO: Escape HTML special characters
String::from("{c} "))
.collect::()
+ "\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 = read_rows(input).collect::, _>>()?;
let columns = column_order(&rows);
Ok(String::from(HEADER)
+ &render_column_headers(&columns)
+ &rows
.into_iter()
.map(|r| render_row(&columns, &r))
.collect::()
+ FOOTER)
}
#[cfg(test)]
mod tests {
use super::*;
#[test]
fn test_parse_entry() {
assert_eq!(
Entry::from("foo"),
Entry {
col: String::from("foo"),
instance: None
}
);
assert_eq!(
Entry::from("foo:bar"),
Entry {
col: String::from("foo"),
instance: Some(String::from("bar"))
}
);
assert_eq!(
Entry::from("foo: bar"),
Entry {
col: String::from("foo"),
instance: Some(String::from("bar"))
}
);
}
#[test]
fn test_read_rows() {
assert_eq!(
read_rows(&b"foo"[..]).flatten().collect::>(),
vec![RowInput {
label: String::from("foo"),
entries: vec![]
}]
);
assert_eq!(
read_rows(&b"bar"[..]).flatten().collect::>(),
vec![RowInput {
label: String::from("bar"),
entries: vec![]
}]
);
assert_eq!(
read_rows(&b"foo\nbar\n"[..]).flatten().collect::>(),
vec![
RowInput {
label: String::from("foo"),
entries: vec![]
},
RowInput {
label: String::from("bar"),
entries: vec![]
}
]
);
assert_eq!(
read_rows(&b"foo\n bar\n"[..]).flatten().collect::>(),
vec![RowInput {
label: String::from("foo"),
entries: vec![Entry::from("bar")]
}]
);
assert_eq!(
read_rows(&b"foo\n bar\n baz\n"[..])
.flatten()
.collect::>(),
vec![RowInput {
label: String::from("foo"),
entries: vec![Entry::from("bar"), Entry::from("baz")]
}]
);
assert_eq!(
read_rows(&b"foo\n\nbar\n"[..])
.flatten()
.collect::>(),
vec![
RowInput {
label: String::from("foo"),
entries: vec![]
},
RowInput {
label: String::from("bar"),
entries: vec![]
}
]
);
assert_eq!(
read_rows(&b"foo\n \nbar\n"[..])
.flatten()
.collect::>(),
vec![
RowInput {
label: String::from("foo"),
entries: vec![]
},
RowInput {
label: String::from("bar"),
entries: vec![]
}
]
);
assert_eq!(
read_rows(&b"foo \n bar \n"[..])
.flatten()
.collect::>(),
vec![RowInput {
label: String::from("foo"),
entries: vec![Entry::from("bar")]
}]
);
let bad = read_rows(&b" foo"[..]).next().unwrap();
assert!(bad.is_err());
assert!(format!("{bad:?}").contains("1: Entry with no header"));
let bad2 = read_rows(&b"foo\n\n bar"[..]).nth(1).unwrap();
assert!(bad2.is_err());
assert!(format!("{bad2:?}").contains("3: Entry with no header"));
}
#[test]
fn test_column_counts() {
assert_eq!(
column_counts(
&read_rows(&b"foo\n bar\n baz\n"[..])
.collect::, _>>()
.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"[..])
.collect::, _>>()
.unwrap()
),
vec![(1, String::from("bar")), (2, String::from("baz"))]
);
assert_eq!(
column_counts(
&read_rows(&b"foo\n bar\n bar\n baz\n bar\nquux\n baz"[..])
.collect::, _>>()
.unwrap()
),
vec![(1, String::from("bar")), (2, String::from("baz"))]
);
assert_eq!(
column_counts(
&read_rows(&b"foo\n bar: 1\n bar: 2\n baz\n bar\nquux\n baz"[..])
.collect::, _>>()
.unwrap()
),
vec![(1, String::from("bar")), (2, String::from("baz"))]
);
}
#[test]
fn test_render_cell() {
assert_eq!(
render_cell(
"foo",
&RowInput {
label: String::from("nope"),
entries: vec![]
}
),
String::from("2 ")
);
assert_eq!(
render_cell(
"foo",
&RowInput {
label: String::from("nope"),
entries: vec![Entry::from("foo: 5"), Entry::from("foo: 10")]
}
),
String::from("5 10 ")
);
assert_eq!(
render_cell(
"foo",
&RowInput {
label: String::from("nope"),
entries: vec![Entry::from("foo: 5"), Entry::from("foo")]
}
),
String::from("5 ✓ ")
);
}
}