feat: Sort subreddit posts by most comments

lib/bdfr_browser/http/plug.ex

@@ -123,6 +123,29 @@ defmodule BdfrBrowser.HTTP.Plug do
     |> send_resp(200, content)
   end
 
+  get "/s/:subreddits/most_comments" do
+    subreddit_names = String.split(subreddits, "+")
+    subreddit_records = Subreddit.multiple_names(subreddit_names) |> Repo.all()
+    {:ok, range_start} = Date.from_iso8601("1970-01-01")
+    range_end = Date.utc_today()
+
+    tpl_args = [
+      subreddit: subreddit_names,
+      date: "Most Comments",
+      posts:
+        subreddit_records
+        |> Post.during_range(range_start, range_end, :most_comments)
+        |> Post.with_comments(1)
+        |> Repo.all()
+    ]
+
+    content = render_template("subreddit_posts", tpl_args)
+
+    conn
+    |> put_resp_header("content-type", "text/html; charset=utf-8")
+    |> send_resp(200, content)
+  end
+
   get "/chats" do
     tpl_args = [chats: Chat.listing() |> Repo.all()]
     content = render_template("chats", tpl_args)

lib/bdfr_browser/post.ex

@@ -1,7 +1,7 @@
 defmodule BdfrBrowser.Post do
   use Ecto.Schema
 
-  import Ecto.Query, only: [from: 2]
+  import Ecto.Query, only: [dynamic: 1, dynamic: 2, from: 2, having: 3]
 
   alias BdfrBrowser.{Comment, Subreddit}
 
@@ -46,7 +46,9 @@ defmodule BdfrBrowser.Post do
     during_range(subreddit, Date.beginning_of_month(d), Date.end_of_month(d))
   end
 
-  def during_range(subreddits, start_date, end_date) when is_list(subreddits) do
+  def during_range(subreddits, start_date, end_date, sort_field \\ :posted_at)
+
+  def during_range(subreddits, start_date, end_date, sort_field) when is_list(subreddits) do
     subreddit_ids = for s <- subreddits, do: s.id
 
     from(p in __MODULE__,
@@ -58,18 +60,19 @@ defmodule BdfrBrowser.Post do
         url: p.url,
         author: p.author,
         posted_at: p.posted_at,
-        num_comments: count(c.id),
+        num_comments: selected_as(count(c.id), :num_comments),
-        subreddit: s.name
+        subreddit: s.name,
+        date: fragment("to_char(?, 'YYYY-MM')", p.posted_at)
       },
       where:
         p.subreddit_id in ^subreddit_ids and type(p.posted_at, :date) >= ^start_date and
           type(p.posted_at, :date) <= ^end_date,
-      order_by: [desc: p.posted_at],
+      order_by: ^dynamic_sort(sort_field),
       group_by: [p.id, s.name]
     )
   end
 
-  def during_range(subreddit, start_date, end_date) do
+  def during_range(subreddit, start_date, end_date, sort_field) do
     from(p in __MODULE__,
       left_join: c in assoc(p, :comments),
       join: s in assoc(p, :subreddit),
@@ -79,17 +82,22 @@ defmodule BdfrBrowser.Post do
         url: p.url,
         author: p.author,
         posted_at: p.posted_at,
-        num_comments: count(c.id),
+        num_comments: selected_as(count(c.id), :num_comments),
-        subreddit: s.name
+        subreddit: s.name,
+        date: fragment("to_char(?, 'YYYY-MM')", p.posted_at)
       },
       where:
         p.subreddit_id == ^subreddit.id and type(p.posted_at, :date) >= ^start_date and
           type(p.posted_at, :date) <= ^end_date,
-      order_by: [desc: p.posted_at],
+      order_by: ^dynamic_sort(sort_field),
       group_by: [p.id, s.name]
     )
   end
 
+  def with_comments(query, more_than \\ 0) do
+    having(query, [p, c, s], count(c.id) > ^more_than)
+  end
+
   def get_full(id) do
     from(p in __MODULE__,
       where: p.id == ^id,
@@ -169,4 +177,7 @@ defmodule BdfrBrowser.Post do
       group_by: [p.id, s.name]
     )
   end
+
+  defp dynamic_sort(:posted_at), do: [{:desc, dynamic([p], p.posted_at)}]
+  defp dynamic_sort(:most_comments), do: dynamic(fragment("num_comments DESC"))
 end

priv/templates/http/post.eex

@@ -12,7 +12,9 @@
 <p>
   <small><%= BdfrBrowser.RenderUtils.link_to_user(post.author) %></small>
   -
-  <small><%= DateTime.to_iso8601(post.posted_at) %></small>
+  <small><%= BdfrBrowser.RenderUtils.format_date(post.posted_at, :long) %></small>
+  -
+  <small><i class="bi bi-arrow-up-square"></i> <%= Float.round(post.upvote_ratio * 100, 1) %>%</small>
   -
   <a href="https://www.reddit.com<%= post.permalink %>" rel="noreferrer">Open reddit</a>
 </p>

priv/templates/http/subreddit.eex

@@ -12,7 +12,7 @@
 </nav>
 
 <h2>
-  <%= if is_list(subreddit) do %>
+  <%= if is_list(subreddit) and length(subreddit) > 1 do %>
     Multi-Reddit
   <% else %>
     <%= subreddit %>
@@ -41,6 +41,12 @@
 
 <div class="row text-center">
   <div class="d-grid gap-2 col-12 mx-auto">
+    <%= if is_list(subreddit) do %>
+      <a class="btn btn-outline-info btn-lg" href="/s/<%= Enum.join(subreddit, "+") %>/most_comments" role="button">Most Comments</a>
+    <% else %>
+      <a class="btn btn-outline-info btn-lg" href="/s/<%= subreddit %>/most_comments" role="button">Most Comments</a>
+    <% end %>
+
     <%= for date <- dates do %>
       <%= if is_list(subreddit) do %>
         <a class="btn btn-outline-secondary btn-lg" href="/m/<%= Enum.join(subreddit, "+") %>/<%= date %>" role="button"><%= date %></a>

priv/templates/http/subreddit_posts.eex

@@ -13,7 +13,7 @@
 </nav>
 
 <h2>
-  <%= if is_list(subreddit) do %>
+  <%= if is_list(subreddit) and length(subreddit) > 1 do %>
     Multi-Reddit
   <% else %>
     <%= subreddit %>
@@ -25,7 +25,7 @@
     <%= for post <- posts do %>
       <div class="card">
         <div class="card-body">
-          <h5 class="card-title"><a href="/r/<%= post.subreddit %>/<%= date %>/<%= post.id %>"><%= post.title %></a></h5>
+          <h5 class="card-title"><a href="/r/<%= post.subreddit %>/<%= post.date %>/<%= post.id %>"><%= post.title %></a></h5>
           <h6 class="card-subtitle mb-2 text-body-secondary">
             <small>
               <%= BdfrBrowser.RenderUtils.post_type_icon(post.url) %>