today/src/parse/line.rs

102 lines
2.6 KiB
Rust

use std::result;
use chrono::NaiveDate;
use crate::commands::{BirthdaySpec, Done, Spec};
use super::error::ParseError;
#[derive(Debug)]
pub enum Line {
Empty,
Indented(String),
Task(String),
Note(String),
Birthday(String),
Date(Spec),
BDate(BirthdaySpec),
From(NaiveDate),
Until(NaiveDate),
Except(NaiveDate),
Done(Done),
}
#[derive(Debug, thiserror::Error)]
pub enum Reason {
#[error("unknown format")]
UnknownFormat,
#[error("unknown command {0:?}")]
UnknownCommand(String),
#[error("empty command body")]
EmptyCommand,
}
type Result<T> = result::Result<T, ParseError>;
pub fn parse_lines(content: &str) -> Result<Vec<Line>> {
content
.lines()
.enumerate()
.map(|(line, content)| parse_line(line, content))
.collect()
}
fn parse_line(line: usize, content: &str) -> Result<Line> {
println!("Parsing line {:?}", content);
if content.is_empty() {
Ok(Line::Empty)
} else if content.starts_with('\t') || content.starts_with(' ') {
Ok(Line::Indented(content.to_string()))
} else if let Some((name, rest)) = parse_command(content) {
let rest = rest.trim();
if rest.is_empty() {
return ParseError::pack(line, Reason::EmptyCommand);
}
match name {
"TASK" => Ok(Line::Task(rest.to_string())),
"NOTE" => Ok(Line::Note(rest.to_string())),
"BIRTHDAY" => Ok(Line::Birthday(rest.to_string())),
"DATE" => parse_date(rest),
"BDATE" => parse_bdate(rest),
"FROM" => parse_datum(rest).map(Line::From),
"UNTIL" => parse_datum(rest).map(Line::Until),
"EXCEPT" => parse_datum(rest).map(Line::Except),
"DONE" => parse_done(rest),
_ => ParseError::pack(line, Reason::UnknownCommand(name.to_string())),
}
} else {
ParseError::pack(line, Reason::UnknownFormat)
}
}
fn parse_command(line: &str) -> Option<(&str, &str)> {
if let Some(space) = line.find(' ') {
let name = &line[..space];
let content = &line[space + 1..];
Some((name, content))
} else {
None
}
}
fn parse_date(s: &str) -> Result<Line> {
println!(" parsing date from {:?}", s);
Ok(Line::Empty) // TODO
}
fn parse_bdate(s: &str) -> Result<Line> {
println!(" parsing bdate from {:?}", s);
Ok(Line::Empty) // TODO
}
fn parse_datum(s: &str) -> Result<NaiveDate> {
println!(" parsing datum from {:?}", s);
Ok(NaiveDate::from_ymd(2015, 3, 14)) // TODO
}
fn parse_done(s: &str) -> Result<Line> {
println!(" parsing done from {:?}", s);
Ok(Line::Empty) // TODO
}