Prepare dijkstra in path command

brood/src/commands/path.rs

@@ -2,32 +2,67 @@ use std::fs::File;
 use std::io::{self, BufReader};
 use std::path::Path;
 
-use crate::data::AdjacencyList;
+use crate::data::{AdjacencyList, Page, PageInfo};
 use crate::util;
 
+fn find_index_of_title(pages: &[Page<PageInfo>], title: &str) -> u32 {
+    let title = util::normalize_link(title);
+    pages
+        .iter()
+        .enumerate()
+        .filter(|(_, p)| !p.data.redirect)
+        .find(|(_, p)| util::normalize_link(&p.data.title) == title)
+        .map(|(i, _)| i)
+        .expect("invalid title") as u32
+}
+
+struct DijkstraPageInfo {
+    distance: u32,
+    prev_page_idx: u32,
+}
+
+impl Default for DijkstraPageInfo {
+    fn default() -> Self {
+        Self {
+            distance: u32::MAX,
+            prev_page_idx: u32::MAX,
+        }
+    }
+}
+
+fn dijkstra(
+    mut data: AdjacencyList<DijkstraPageInfo, ()>,
+    from_idx: u32,
+    to_idx: u32,
+) -> Option<Vec<u32>> {
+    todo!()
+}
+
 pub fn path(datafile: &Path, from: &str, to: &str) -> io::Result<()> {
-    eprintln!(">> Import");
+    println!(">> Import");
     let mut databuf = BufReader::new(File::open(datafile)?);
     let data = AdjacencyList::read(&mut databuf)?;
+    let pages = data.pages.clone();
+    let data = data
+        .change_page_data(&|_| DijkstraPageInfo::default())
+        .change_link_data(&|_| ());
 
-    eprintln!(">> Locate from and to");
-    let from = util::normalize_link(from);
-    let to = util::normalize_link(to);
-    let (from_i, from_p) = data
-        .pages
-        .iter()
-        .enumerate()
-        .filter(|(_, p)| !p.data.redirect)
-        .find(|(_, p)| util::normalize_link(&p.data.title) == from)
-        .unwrap_or_else(|| panic!("no article called {from}"));
-    let (to_i, to_p) = data
-        .pages
-        .iter()
-        .enumerate()
-        .filter(|(_, p)| !p.data.redirect)
-        .find(|(_, p)| util::normalize_link(&p.data.title) == to)
-        .unwrap_or_else(|| panic!("no article called {to}"));
-    dbg!(from_i, from_p, to_i, to_p);
+    println!(">> Locate from and to");
+    let from_idx = find_index_of_title(&pages, from);
+    let to_idx = find_index_of_title(&pages, to);
+
+    println!(">> Find path");
+    let path = dijkstra(data, from_idx, to_idx);
+
+    if let Some(path) = path {
+        println!("Path found:");
+        for page_idx in path {
+            let page = &pages[page_idx as usize];
+            println!(" - {}", page.data.title);
+        }
+    } else {
+        println!("No path found");
+    }
 
     Ok(())
 }