From a2debf5b2cb551e1f881f6674883cf8847d2917c Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Tom=C3=A1=C5=A1=20Ml=C3=A1dek?= <t@mldk.cz>
Date: Tue, 5 Oct 2021 22:34:29 +0200
Subject: [PATCH] add tag display to sidebar

---
 src/main.rs         | 31 ++++++++++++++++++++++++++++---
 templates/main.css  |  4 ++++
 templates/main.html | 14 ++++++++++++++
 3 files changed, 46 insertions(+), 3 deletions(-)

diff --git a/src/main.rs b/src/main.rs
index ff3e6a4..50cc6fe 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -14,6 +14,7 @@ use percent_encoding::{percent_decode_str, utf8_percent_encode};
 use pulldown_cmark::{html, Event, Options, Parser, Tag};
 use regex::{Captures, Regex};
 use slug::slugify;
+use std::cmp::Reverse;
 use std::collections::HashMap;
 use std::fs::File;
 use std::io::Read;
@@ -44,6 +45,7 @@ struct MutableState {
 struct GardenCache {
     pages: HashMap<String, ParsedPage>,
     files: Vec<PathBuf>,
+    tags: HashMap<String, u32>,
 }
 
 impl Default for GardenCache {
@@ -51,6 +53,7 @@ impl Default for GardenCache {
         GardenCache {
             pages: HashMap::new(),
             files: vec![],
+            tags: HashMap::new(),
         }
     }
 }
@@ -297,6 +300,12 @@ async fn render(
         data.title.as_ref().unwrap_or(&"Digital Garden".to_string()),
     );
     context.insert("files", &cache.files);
+
+    let mut tags: Vec<(&String, &u32)> = cache.tags.iter().collect();
+    tags.sort_by_key(|(t, _)| *t);
+    tags.sort_by_key(|(_, n)| Reverse(*n));
+    context.insert("tags", &tags);
+
     context.insert(
         "recently_changed",
         &recently_changed
@@ -387,6 +396,7 @@ fn update_garden<P: AsRef<Path>>(
     }
 
     let mut pages = current.pages;
+    let mut tags = current.tags;
 
     let markdown_paths = files
         .iter()
@@ -428,9 +438,13 @@ fn update_garden<P: AsRef<Path>>(
                 },
             },
         );
+
+        result.tags.into_iter().for_each(|tag| {
+            *tags.entry(tag).or_insert(0) += 1;
+        });
     }
 
-    let result = GardenCache { pages, files };
+    let result = GardenCache { pages, files, tags };
     trace!("{:#?}", result);
     Ok(result)
 }
@@ -439,6 +453,7 @@ struct ParseResult {
     html: String,
     title: Option<String>,
     links: Vec<String>,
+    tags: Vec<String>,
 }
 
 fn parse_garden<S: AsRef<str>>(text: S) -> anyhow::Result<ParseResult> {
@@ -448,10 +463,19 @@ fn parse_garden<S: AsRef<str>>(text: S) -> anyhow::Result<ParseResult> {
     let mut last_nontext_event: Option<Event> = None;
 
     let mut links: Vec<String> = vec![];
+    let mut tags: Vec<String> = vec![];
 
     let parser = Parser::new_ext(text.as_ref(), Options::all()).map(|event| {
-        if let Event::Start(Tag::Link(_, str, _)) = &event {
-            links.push(str.to_string());
+        if let Event::Start(Tag::Link(_, dest, _)) = &event {
+            links.push(dest.to_string());
+        }
+
+        if let Some(Event::Start(Tag::Link(_, dest, _))) = &last_nontext_event {
+            if let Event::Text(str) = &event {
+                if str.starts_with("#") {
+                    tags.push(dest.to_string());
+                }
+            }
         }
 
         if let Some(Event::Start(Tag::Heading(hl))) = last_nontext_event {
@@ -476,6 +500,7 @@ fn parse_garden<S: AsRef<str>>(text: S) -> anyhow::Result<ParseResult> {
         html,
         title: top_heading_text,
         links,
+        tags,
     })
 }
 
diff --git a/templates/main.css b/templates/main.css
index 251b941..5271a96 100644
--- a/templates/main.css
+++ b/templates/main.css
@@ -183,6 +183,10 @@ nav .graph-view {
     text-align: center;
 }
 
+.tag .count {
+    opacity: .5;
+}
+
 footer {
     padding: 1em 0;
     color: gray;
diff --git a/templates/main.html b/templates/main.html
index 982a902..46aa998 100644
--- a/templates/main.html
+++ b/templates/main.html
@@ -73,6 +73,20 @@
                     {% endfor %}
                 </ul>
             </section>
+            {% if tags %}
+            <section>
+                <h2>Tags</h2>
+                <ul>
+                    {% for tag_cnt in tags %}
+                        <li class="tag">
+                            <a href="/{{tag_cnt.0}}">
+                                <span class="label">#{{tag_cnt.0}}</span> <span class="count">({{tag_cnt.1}})</span>
+                            </a>
+                        </li>
+                    {% endfor %}
+                </ul>
+            </section>
+            {% endif %}
             <section class="graph-view">
                 <a href="/!graph">Graph view (beta)</a>
             </section>