]> git.scottworley.com Git - voter/blobdiff - src/main.rs
Update vote counts to reflect local votes
[voter] / src / main.rs
index 994ffac9b049ab2c6a8d0795ea067a47e5e9e663..528a2301c04a44ba486551cb4e5568ff3e117075 100644 (file)
@@ -1,4 +1,5 @@
 use rand::prelude::*;
+use std::collections::{HashMap, HashSet};
 use std::io::prelude::*;
 use std::path::{Path, PathBuf};
 
@@ -44,15 +45,42 @@ fn get_voter(request: &cgi::Request) -> Result<&[u8], cgi::Response> {
     }
 }
 
+fn tally_votes(dir: PathBuf) -> std::io::Result<HashMap<String, HashSet<String>>> {
+    let mut tally: HashMap<String, HashSet<String>> = HashMap::new();
+    let vfile = std::fs::File::open(dir.join("votes"))?;
+    for liner in std::io::BufReader::new(vfile).lines() {
+        let line = liner?;
+        if let Some((voter, datum)) = line.split_once(' ') {
+            if voter.len() == COOKIE_LENGTH {
+                if let Some((vote, candidate)) = datum.split_once(' ') {
+                    if vote == "0" {
+                        if let Some(entry) = tally.get_mut(candidate) {
+                            entry.remove(voter);
+                        }
+                    } else if vote == "1" {
+                        tally
+                            .entry(candidate.to_owned())
+                            .or_default()
+                            .insert(voter.to_owned());
+                    }
+                }
+            }
+        }
+    }
+    Ok(tally)
+}
+
 fn make_random_id() -> [u8; COOKIE_LENGTH] {
-    std::iter::from_fn(random)
-        .filter(|c| {
-            (b'A'..=b'Z').contains(c) || (b'a'..=b'z').contains(c) || (b'0'..=b'9').contains(c)
-        })
-        .take(COOKIE_LENGTH)
-        .collect::<Vec<_>>()
-        .try_into()
-        .unwrap()
+    let mut id = [0; COOKIE_LENGTH];
+    for i in 0..COOKIE_LENGTH {
+        while !(b'A'..=b'Z').contains(&id[i])
+            && !(b'a'..=b'z').contains(&id[i])
+            && !(b'0'..=b'9').contains(&id[i])
+        {
+            id[i] = random()
+        }
+    }
+    id
 }
 
 fn set_cookie(mut response: cgi::Response, path: &str) -> Result<cgi::Response, cgi::Response> {
@@ -73,19 +101,105 @@ fn set_cookie(mut response: cgi::Response, path: &str) -> Result<cgi::Response,
     Ok(response)
 }
 
+const HTML_HEADER: &str = "<!DOCTYPE html>
+<html>
+  <head>
+    <meta charset=\"utf-8\">
+    <title>Vote!</title>
+    <style>
+      th { font-size: 70%; text-align: left }
+      input { transform: scale(1.5) }
+      div { animation: 2s infinite linear spin }
+      @keyframes spin {
+        from { transform:rotate(0) }
+        to { transform:rotate(1turn) }
+      }
+    </style>
+    <script>
+      window.onload = function() {
+        for (cb of document.getElementsByTagName('input')) {
+          cb.addEventListener('click', (function(cb) {
+            return function() {
+              cb.style.display = 'none'
+              const spin = document.createElement('div')
+              spin.appendChild(document.createTextNode('⏳'))
+              cb.parentElement.insertBefore(spin, cb)
+
+              const req = new XMLHttpRequest()
+              req.addEventListener('load', function(e) {
+                cb.parentElement.removeChild(cb.previousElementSibling)
+                if (req.status == 200) {
+                    cb.style.display = ''
+                    const delta = cb.checked ? 1 : -1
+                    const count_td = cb.parentElement.previousElementSibling
+                    count_td.textContent = parseInt(count_td.textContent) + delta
+                } else {
+                   cb.parentElement.insertBefore(document.createTextNode('❗'), cb)
+                }
+              })
+              req.open('PUT', window.location.href)
+              req.send((cb.checked ? 1 : 0) + ' ' + cb.parentElement.nextElementSibling.innerHTML)
+            }
+          })(cb))
+          cb.disabled = false
+        }
+      }
+    </script>
+  </head>
+  <body>
+    <table>
+      <tr>
+        <th>Count</th>
+        <th>Vote</th>
+        <th>Candidate</th>
+      </tr>";
+const HTML_FOOTER: &str = "
+    </table>
+  </body>
+</html>";
+
+fn supports(tally: &HashMap<String, HashSet<String>>, me: &str, candidate: &str) -> bool {
+    tally
+        .get(candidate)
+        .map(|supporters| supporters.contains(me))
+        .unwrap_or(false)
+}
+
 fn prompt_for_vote(dir: PathBuf, request: cgi::Request) -> Result<cgi::Response, cgi::Response> {
     let voter = get_voter(&request);
+    let me = if let Ok(id) = voter {
+        std::str::from_utf8(id).ok()
+    } else {
+        None
+    };
+    let tally =
+        tally_votes(dir.clone()).map_err(|_| cgi::text_response(503, "Couldn't tally votes"))?;
     let cfile = std::fs::File::open(dir.join("candidates"))
         .map_err(|_| cgi::text_response(503, "No candidates"))?;
     let mut response = cgi::html_response(
         200,
-        std::iter::once(Ok("<html><body><table>".to_owned()))
-            .chain(
-                std::io::BufReader::new(cfile)
-                    .lines()
-                    .map(|rc| rc.map(|c| format!("<tr><td>{c}</td></tr>"))),
-            )
-            .chain(std::iter::once(Ok("</table></body></html>".to_owned())))
+        std::iter::once(Ok(HTML_HEADER.to_owned()))
+            .chain(std::io::BufReader::new(cfile).lines().map(|rc| {
+                rc.map(|c| {
+                    let count = tally
+                        .get(&c)
+                        .map(|supporters| supporters.len())
+                        .unwrap_or(0);
+                    let checked = if me.map(|me| supports(&tally, me, &c)).unwrap_or(false) {
+                        "checked"
+                    } else {
+                        ""
+                    };
+                    format!(
+                        "<tr>
+                        <td>{count}</td>
+                        <td><input type=\"checkbox\" autocomplete=\"off\" {checked} disabled></td>
+                        <td>{c}</td>
+                        </tr>"
+                    )
+                })
+            }))
+            .chain(std::iter::once(Ok(HTML_FOOTER.to_owned())))
             .collect::<std::io::Result<String>>()
             .map_err(|_| cgi::text_response(503, "Missing candidates"))?,
     );