From 633fafd4f50a7dc773aeaa10806525b68ffebae9 Mon Sep 17 00:00:00 2001
From: Austin Wise <AustinWise@gmail.com>
Date: Wed, 2 Feb 2022 00:11:10 -0800
Subject: [PATCH] Add pagination

---
 src/requests.rs               | 29 +++++++++++++++++++++++------
 src/templates.rs              | 11 ++++++++++-
 src/wiki.rs                   | 19 +++++++++++++++----
 templates/search_results.html | 34 ++++++++++++++++++++++++++--------
 4 files changed, 74 insertions(+), 19 deletions(-)

diff --git a/src/requests.rs b/src/requests.rs
index c36ad24..7713d2d 100644
--- a/src/requests.rs
+++ b/src/requests.rs
@@ -285,15 +285,32 @@ fn overview(path: WikiPagePath, w: Wiki) -> Result<response::content::Html<Strin
     overview_inner(path, w)
 }
 
-fn search_inner(q: &str, w: Wiki) -> Result<response::content::Html<String>, MyError> {
-    let results = w.search(q)?;
-    let html = render_search_results(q, results)?;
+fn search_inner(
+    q: &str,
+    offset: Option<usize>,
+    w: Wiki,
+) -> Result<response::content::Html<String>, MyError> {
+    const RESULTS_PER_PAGE: usize = 10;
+    let results = w.search(q, RESULTS_PER_PAGE, offset)?;
+    let prev_url = offset.and_then(|v| {
+        if v >= RESULTS_PER_PAGE {
+            Some(uri!(search(q, Some(v - RESULTS_PER_PAGE))).to_string())
+        } else {
+            None
+        }
+    });
+    let next_url = Some(uri!(search(q, Some(offset.unwrap_or(0) + RESULTS_PER_PAGE))).to_string());
+    let html = render_search_results(q, results, prev_url, next_url)?;
     Ok(response::content::Html(html))
 }
 
-#[get("/search?<q>")]
-fn search(q: &str, w: Wiki) -> Result<response::content::Html<String>, MyError> {
-    search_inner(q, w)
+#[get("/search?<q>&<offset>")]
+fn search(
+    q: &str,
+    offset: Option<usize>,
+    w: Wiki,
+) -> Result<response::content::Html<String>, MyError> {
+    search_inner(q, offset, w)
 }
 
 #[get("/")]
diff --git a/src/templates.rs b/src/templates.rs
index d3e9cf2..ab0629b 100644
--- a/src/templates.rs
+++ b/src/templates.rs
@@ -166,9 +166,16 @@ struct SearchResultsTemplate<'a> {
     query: &'a str,
     documents: Vec<SearchResult>,
     breadcrumbs: Vec<Breadcrumb<'a>>,
+    prev_url: Option<String>,
+    next_url: Option<String>,
 }
 
-pub fn render_search_results(query: &str, documents: Vec<SearchResult>) -> askama::Result<String> {
+pub fn render_search_results(
+    query: &str,
+    documents: Vec<SearchResult>,
+    prev_url: Option<String>,
+    next_url: Option<String>,
+) -> askama::Result<String> {
     let primer_css_uri = &primer_css_uri();
     let favicon_png_uri = &favicon_png_uri();
     let breadcrumbs = vec![];
@@ -179,6 +186,8 @@ pub fn render_search_results(query: &str, documents: Vec<SearchResult>) -> askam
         query,
         breadcrumbs,
         documents,
+        prev_url,
+        next_url,
     };
     template.render()
 }
diff --git a/src/wiki.rs b/src/wiki.rs
index bd0bad0..8561fd4 100644
--- a/src/wiki.rs
+++ b/src/wiki.rs
@@ -125,14 +125,16 @@ fn create_index(settings: &Settings, repository: &RepoBox) -> Result<Index, MyEr
     Ok(index)
 }
 
-// TODO: this does not belong at all in the Wiki, it belongs more in request handeling
+// TODO: this does not belong at all in the Wiki, it belongs more in request handling
 fn highlight(snippet: Snippet) -> String {
     let mut result = String::new();
     let mut start_from = 0;
 
     for fragment_range in snippet.highlighted() {
         result.push_str(&snippet.fragments()[start_from..fragment_range.start]);
-        result.push_str("<span class=\"color-bg-accent-emphasis color-fg-on-emphasis p-1 rounded mb-4\">");
+        result.push_str(
+            "<span class=\"color-bg-accent-emphasis color-fg-on-emphasis p-1 rounded mb-4\">",
+        );
         result.push_str(&snippet.fragments()[fragment_range.clone()]);
         result.push_str("</span>");
         start_from = fragment_range.end;
@@ -177,7 +179,12 @@ impl Wiki {
         self.0.repository.enumerate_files(directory)
     }
 
-    pub fn search(&self, query: &str) -> Result<Vec<SearchResult>, MyError> {
+    pub fn search(
+        &self,
+        query: &str,
+        num_results: usize,
+        offset: Option<usize>,
+    ) -> Result<Vec<SearchResult>, MyError> {
         let reader = self
             .0
             .index
@@ -192,7 +199,11 @@ impl Wiki {
 
         let query = query_parser.parse_query(query)?;
 
-        let top_docs = searcher.search(&query, &TopDocs::with_limit(10))?;
+        let mut top_docs = TopDocs::with_limit(num_results);
+        if let Some(offset) = offset {
+            top_docs = top_docs.and_offset(offset);
+        }
+        let top_docs = searcher.search(&query, &top_docs)?;
 
         let snippet_generator = SnippetGenerator::create(&searcher, &*query, fields.body)?;
 
diff --git a/templates/search_results.html b/templates/search_results.html
index f2ec6c3..c7ff690 100644
--- a/templates/search_results.html
+++ b/templates/search_results.html
@@ -2,12 +2,12 @@
 
 {% block extra_scripts %}
 <script>
-window.addEventListener('DOMContentLoaded', (event) => {
-    // Place the current search query back into the search box
-    let params = (new URL(document.location)).searchParams
-    let input = document.getElementById('search-query');
-    input.value = params.get('q');
-});
+    window.addEventListener('DOMContentLoaded', (event) => {
+        // Place the current search query back into the search box
+        let params = (new URL(document.location)).searchParams
+        let input = document.getElementById('search-query');
+        input.value = params.get('q');
+    });
 </script>
 {% endblock %}
 
@@ -25,8 +25,8 @@ <h1 class="pt-4">
         <li class="Box-row">
             <span class="Counter Counter--gray tooltipped tooltipped-w"
                 aria-label="score: {{doc.score}}">{{doc.score}}</span>
-            <span class="text-bold"><a href="/page{{doc.path}}">{{doc.title}}</a></span> <span
-                class="text-gray-light">- {{doc.path}}</span>
+            <span class="text-bold"><a href="/page{{doc.path}}">{{doc.title}}</a></span> <span class="text-gray-light">-
+                {{doc.path}}</span>
         </li>
         <div class="Box-row">
             {{doc.snippet_html}}
@@ -35,4 +35,22 @@ <h1 class="pt-4">
     </ul>
 </div>
 
+<nav class="paginate-container" aria-label="Pagination">
+    <div class="pagination">
+        {% match prev_url %}
+        {% when Some with (url) %}
+        <a class="previous_page" rel="prev" href="{{url}}" aria-label="Previous Page">Previous</a>
+        {% when None %}
+        <span class="previous_page" aria-disabled="true">Previous</span>
+        {% endmatch %}
+
+        {% match next_url %}
+        {% when Some with (url) %}
+        <a class="next_page" rel="next" href="{{url}}" aria-label="Next Page">Next</a>
+        {% when None %}
+        <span class="next_page" aria-disabled="true">Next</span>
+        {% endmatch %}
+    </div>
+</nav>
+
 {% endblock %}
\ No newline at end of file