wikilyze/brood/src/commands/path.rs

77 lines
2.1 KiB
Rust

use std::{
fs::File,
io::{self, BufReader},
path::Path,
};
use crate::{
algo::Dijkstra,
data::{info::PageInfo, store},
graph::{Graph, NodeIdx},
util,
};
pub fn find_index_of_title(pages: &[PageInfo], title: &str) -> NodeIdx {
let title = util::normalize_link(title);
pages
.iter()
.enumerate()
.find(|(_, p)| util::normalize_link(&p.title) == title)
.map(|(i, _)| NodeIdx::new(i))
.expect("invalid title")
}
pub fn resolve_redirects(pages: &[PageInfo], graph: &Graph, mut page: NodeIdx) -> NodeIdx {
loop {
if pages[page.usize()].redirect {
if let Some(next) = graph.edges_for(page).first() {
page = *next;
continue;
}
}
return page;
}
}
pub fn path(datafile: &Path, start: &str, goal: &str) -> io::Result<()> {
println!(">> Import");
let mut databuf = BufReader::new(File::open(datafile)?);
let (pages, _links, graph) = store::read_graph(&mut databuf)?;
println!(">> Locate from and to");
let start = resolve_redirects(&pages, &graph, find_index_of_title(&pages, start));
let goal = resolve_redirects(&pages, &graph, find_index_of_title(&pages, goal));
println!("Start: {:?}", pages[start.usize()].title);
println!("Goal: {:?}", pages[goal.usize()].title);
println!(">> Find path");
println!("> Preparing dijkstra");
let mut dijkstra = Dijkstra::new(&graph);
println!("> Running dijkstra");
dijkstra.run(
start,
|node| node == goal,
|source, _edge, _target| !pages[source.usize()].redirect as u32,
);
if dijkstra.cost(goal) == u32::MAX {
println!("No path found");
return Ok(());
}
println!("> Collecting path");
let path = dijkstra.path(goal);
let cost = dijkstra.cost(goal);
println!("Path found (cost {cost}, length {}):", path.len());
for page in path {
let info = &pages[page.usize()];
if info.redirect {
println!(" v {:?}", info.title);
} else {
println!(" - {:?}", info.title);
}
}
Ok(())
}