use crate::{Error, Pos};
pub struct Source {
pub text: String,
pub positions: Vec<Pos>,
pub options: Vec<String>,
}
const TEXT_START: usize = 7;
const TEXT_END: usize = 72;
pub fn read(input: &str) -> Result<Source, Error> {
read_file(input, 0)
}
pub fn read_file(input: &str, file: u16) -> Result<Source, Error> {
let mut out = Source { text: String::new(), positions: Vec::new(), options: Vec::new() };
let mut seen_program = false;
let mut open_quote: Option<char> = None;
for (index, raw) in input.lines().enumerate() {
let line = index as u32 + 1;
let chars: Vec<char> = raw.trim_end_matches('\r').chars().map(|c| if c == '\t' { ' ' } else { c }).collect();
let body: String = chars.iter().take(TEXT_END).collect();
if !seen_program && let Some(options) = option_card(&body) {
out.options.extend(options);
continue;
}
let indicator = chars.get(6).copied().unwrap_or(' ');
if matches!(indicator, '*' | '/' | 'D' | 'd') {
continue;
}
let area: Vec<char> = chars.iter().take(TEXT_END).skip(TEXT_START).copied().collect();
if area.iter().all(|c| *c == ' ') {
continue;
}
seen_program = true;
let start_col = TEXT_START as u32 + 1;
if indicator == '-' {
let first = area.iter().position(|c| *c != ' ').unwrap();
let skip = match open_quote {
Some(q) if area[first] == q => first + 1,
Some(_) => return Err(Error::at(Pos { file, line, col: start_col + first as u32 }, "a continued literal must resume with its quote")),
None => {
while out.text.ends_with(' ') {
out.text.pop();
out.positions.pop();
}
first
}
};
for (i, &c) in area.iter().enumerate().skip(skip) {
if floating_comment(&area, i, open_quote) {
break;
}
push(&mut out, c, Pos { file, line, col: start_col + i as u32 }, &mut open_quote);
}
} else {
if open_quote.is_some() {
return Err(Error::at(Pos { file, line, col: 1 }, "a literal runs to the end of the line with no continuation"));
}
out.text.push('\n');
out.positions.push(Pos { file, line, col: 0 });
for (i, &c) in area.iter().enumerate() {
if floating_comment(&area, i, open_quote) {
break;
}
push(&mut out, c, Pos { file, line, col: start_col + i as u32 }, &mut open_quote);
}
if open_quote.is_some() {
for i in area.len()..TEXT_END - TEXT_START {
push(&mut out, ' ', Pos { file, line, col: start_col + i as u32 }, &mut open_quote);
}
}
}
}
if open_quote.is_some() {
return Err(Error::at(out.positions.last().copied().unwrap_or_default(), "an unterminated literal"));
}
Ok(out)
}
fn floating_comment(area: &[char], i: usize, open_quote: Option<char>) -> bool {
open_quote.is_none() && area[i] == '*' && area.get(i + 1) == Some(&'>')
}
fn push(out: &mut Source, c: char, pos: Pos, open_quote: &mut Option<char>) {
match *open_quote {
Some(q) if c == q => *open_quote = None,
None if c == '\'' || c == '"' => *open_quote = Some(c),
_ => {}
}
out.text.push(c);
out.positions.push(pos);
}
fn option_card(line: &str) -> Option<Vec<String>> {
let sequence: String = line.chars().take(6).collect();
let line = if sequence.len() == 6 && sequence.chars().all(|c| c.is_ascii_digit() || c == ' ') { &line[6..] } else { line };
let trimmed = line.trim_start();
let rest = trimmed.strip_prefix("CBL ").or_else(|| trimmed.strip_prefix("PROCESS ")).or_else(|| (trimmed == "CBL" || trimmed == "PROCESS").then_some(""))?;
let (mut options, mut current, mut depth) = (Vec::new(), String::new(), 0i32);
for c in rest.chars() {
match c {
'(' => depth += 1,
')' => depth -= 1,
_ => {}
}
if depth == 0 && (c == ',' || c == ' ') {
if !current.is_empty() {
options.push(std::mem::take(&mut current));
}
} else {
current.push(c);
}
}
if !current.is_empty() {
options.push(current);
}
Some(options)
}
#[cfg(test)]
mod tests {
use super::*;
#[test]
fn option_cards_ahead_of_the_program_are_collected() {
let s = read(" CBL TRUNC(OPT),NUMPROC(PFD) ARITH(EXTEND)\n PROCESS SSRANGE\n IDENTIFICATION DIVISION.\n").unwrap();
assert_eq!(s.options, ["TRUNC(OPT)", "NUMPROC(PFD)", "ARITH(EXTEND)", "SSRANGE"]);
assert_eq!(s.text.trim(), "IDENTIFICATION DIVISION.");
}
#[test]
fn a_suboption_list_stays_whole() {
assert_eq!(option_card("CBL FLAG(I,W),X").unwrap(), ["FLAG(I,W)", "X"]);
}
#[test]
fn sequence_numbers_comments_and_columns_past_72_are_dropped() {
let s = read("000100 IDENTIFICATION DIVISION. SEQ00001\n000200*a comment\n000300/page\n").unwrap();
assert_eq!(s.text.trim(), "IDENTIFICATION DIVISION.");
}
#[test]
fn a_continued_literal_keeps_its_trailing_spaces() {
let first = format!(" 01 A PIC X(70) VALUE 'ABC{}", " ".repeat(72 - 34));
let text = format!("{first}\n - 'DEF'.\n");
let s = read(&text).unwrap();
let literal = &s.text[s.text.find('\'').unwrap()..];
assert_eq!(literal.trim_end(), format!("'ABC{}DEF'.", " ".repeat(40)));
}
#[test]
fn an_option_card_may_carry_a_sequence_number() {
assert_eq!(read("000010 CBL ARITH(EXTEND)\n").unwrap().options, ["ARITH(EXTEND)"]);
}
#[test]
fn a_continued_word_joins_without_a_space() {
let s = read(" MOVE ABC\n - DEF TO X.\n").unwrap();
assert!(s.text.contains("MOVE ABCDEF TO X."));
}
#[test]
fn a_floating_comment_ends_the_line_but_not_inside_a_literal() {
let s = read(" MOVE 1 TO X *> set X\n DISPLAY '*> kept'\n").unwrap();
assert!(s.text.contains("MOVE 1 TO X") && !s.text.contains("set X"));
assert!(s.text.contains("'*> kept'"));
}
#[test]
fn positions_point_at_the_source() {
let s = read(" IDENTIFICATION DIVISION.\n").unwrap();
let i = s.text.find('D').unwrap();
assert_eq!(s.positions[i], Pos { file: 0, line: 1, col: 9 });
}
}