Initial commit

20 files changed, 1271 insertions, 0 deletions

diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..1ed2662
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,4 @@
+venv
+__pycache__
+.vscode/
+.env
diff --git a/Dockerfile b/Dockerfile
new file mode 100644
index 0000000..aabee15
--- /dev/null
+++ b/Dockerfile
@@ -0,0 +1,13 @@
+FROM python:alpine
+
+WORKDIR /app
+COPY requirements.txt ./
+RUN pip install --no-cache-dir -r requirements.txt
+COPY migrations ./migrations
+COPY scripts ./scripts
+COPY static ./static
+COPY templates ./templates
+COPY *.py ./
+
+EXPOSE 8000
+CMD ["sh", "scripts/container_entrypoint.sh"]
diff --git a/LICENSE b/LICENSE
new file mode 100644
index 0000000..261eeb9
--- /dev/null
+++ b/LICENSE
@@ -0,0 +1,201 @@
+                                 Apache License
+                           Version 2.0, January 2004
+                        http://www.apache.org/licenses/
+
+   TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
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diff --git a/app.py b/app.py
new file mode 100644
index 0000000..4c9b9f7
--- /dev/null
+++ b/app.py
@@ -0,0 +1,221 @@
+from dotenv import load_dotenv
+load_dotenv()
+
+import datetime
+from dataclasses import dataclass
+from flask import Flask, render_template, redirect, request, make_response
+app = Flask(__name__)
+
+import db
+
+@dataclass
+class ChoicesByVoter:
+  name: str
+  votes: list[bool]
+
+TITLE_MAX_LENGTH = 100
+DESCRIPTION_MAX_LENGTH = 1000
+AUTHOR_NAME_MAX_LENGTH = 100
+AUTHOR_EMAIL_MAX_LENGTH = 100
+VOTER_NAME_MAX_LENGTH = 100
+
+def voter_voted_on_choice(voter_name: str, choice: db.Choice) -> bool:
+  for vote in choice.votes:
+    if vote.voter_name == voter_name:
+      return True
+  return False
+
+def validation_error(message: str):
+  return render_template("error.html.j2", error=message), 400
+
+@app.route("/")
+def hello_world():
+  created_poll_codes = []
+  for k, _ in request.cookies.items():
+    if k.startswith("diddle_manage_code_"):
+      created_poll_codes.append(k.replace("diddle_manage_code_", ""))
+
+  created_polls = db.get_polls_by_codes(created_poll_codes) if len(created_poll_codes) > 0 else []
+
+  return render_template('index.html.j2',
+                         created_polls=created_polls)
+
+@app.post("/poll/create")
+def create():
+  form = request.form
+
+  if "title" not in form or len(form["title"]) == 0:
+    return validation_error("Title is required")
+  if len(form["title"]) > TITLE_MAX_LENGTH:
+    return validation_error(f"Title must be {TITLE_MAX_LENGTH} characters or fewer")
+  if "description" in form and len(form["description"]) > DESCRIPTION_MAX_LENGTH:
+    return validation_error(f"Description must be {DESCRIPTION_MAX_LENGTH} characters or fewer")
+  if "author_name" not in form or len(form["author_name"]) == 0:
+    return validation_error("Author name is required")
+  if len(form["author_name"]) > AUTHOR_NAME_MAX_LENGTH:
+    return validation_error(f"Author name must be {AUTHOR_NAME_MAX_LENGTH} characters or fewer")
+  if "author_email" in form and len(form["author_email"]) > AUTHOR_EMAIL_MAX_LENGTH:
+    return validation_error(f"Author email must be {AUTHOR_EMAIL_MAX_LENGTH} characters or fewer")
+
+  choices = []
+  poll = db.create_poll(
+    form["title"],
+    form["description"],
+    form["author_name"],
+    form["author_email"],
+    choices,
+  )
+  resp = make_response(
+    redirect(f"/manage/{poll.manage_code}")
+  )
+  resp.set_cookie(f"diddle_manage_code_{poll.manage_code}", "1")
+  return resp
+
+@app.get("/poll/<id>")
+def poll(id):
+  poll = db.get_poll(id)
+  if poll is None:
+    return "Poll not found", 404
+
+  display_mode = request.cookies.get("diddle_display_mode", "table")
+
+  voter_names = []
+  for choice in poll.choices:
+    for vote in choice.votes:
+      if vote.voter_name not in voter_names:
+        voter_names.append(vote.voter_name)
+
+  choices_by_voter = []
+  for voter_name in voter_names:
+    votes: list[bool] = []
+    for choice in poll.choices:
+      voted = voter_voted_on_choice(voter_name, choice)
+      votes.append(voted)
+
+    choices_by_voter.append(
+      ChoicesByVoter(name=voter_name, votes=votes)
+    )
+
+  choices_by_voter.sort(key=lambda x: x.name)
+
+  return render_template('poll.html.j2',
+                         poll=poll,
+                         choices_by_voter=choices_by_voter,
+                         choices=poll.choices,
+                         now=datetime.datetime.now(),
+                         display_mode=display_mode,
+  )
+
+@app.post("/poll/<id>/vote")
+def vote_poll(id):
+  form = request.form
+  if "voter_name" not in form or len(form["voter_name"]) == 0:
+    return validation_error("Voter name is required")
+  if len(form["voter_name"]) > VOTER_NAME_MAX_LENGTH:
+    return validation_error(f"Voter name must be {VOTER_NAME_MAX_LENGTH} characters or fewer")
+
+  voter_name = form["voter_name"]
+  choice_ids = []
+  for k in form.keys():
+    if k.startswith("choice_"):
+      choice_id = k.replace("choice_", "")
+      choice_ids.append(choice_id)
+
+  db.vote_poll(id, voter_name, choice_ids)
+
+  return redirect(f"/poll/{id}")
+
+@app.post("/manage/<code>/update_info")
+def update_poll_info(code):
+  form = request.form
+
+  if "title" not in form or len(form["title"]) == 0:
+    return validation_error("Title is required")
+  if len(form["title"]) > TITLE_MAX_LENGTH:
+    return validation_error(f"Title must be {TITLE_MAX_LENGTH} characters or fewer")
+  if "description" in form and len(form["description"]) > DESCRIPTION_MAX_LENGTH:
+    return validation_error(f"Description must be {DESCRIPTION_MAX_LENGTH} characters or fewer")
+  if "author_name" not in form or len(form["author_name"]) == 0:
+    return validation_error("Author name is required")
+  if len(form["author_name"]) > AUTHOR_NAME_MAX_LENGTH:
+    return validation_error(f"Author name must be {AUTHOR_NAME_MAX_LENGTH} characters or fewer")
+  if "author_email" in form and len(form["author_email"]) > AUTHOR_EMAIL_MAX_LENGTH:
+    return validation_error(f"Author email must be {AUTHOR_EMAIL_MAX_LENGTH} characters or fewer")
+
+  db.update_poll_info(
+    code,
+    form["title"],
+    form["description"],
+    form["author_name"],
+    form["author_email"],
+  )
+
+  return redirect(f"/manage/{code}")
+
+@app.post("/manage/<code>/add_choice")
+def add_choice(code):
+  form = request.form
+  if "start_datetime" not in form or len(form["start_datetime"]) == 0:
+    return validation_error("Start datetime is required")
+  if "end_datetime" not in form or len(form["end_datetime"]) == 0:
+    return validation_error("End datetime is required")
+  if form["start_datetime"] >= form["end_datetime"]:
+    return validation_error("Start datetime must be before end datetime")
+
+  db.add_choice_to_poll(
+    code,
+    form["start_datetime"],
+    form["end_datetime"],
+  )
+
+  return redirect(f"/manage/{code}")
+
+@app.post("/manage/<code>/delete_choice/<choice_id>")
+def delete_choice(code, choice_id):
+  poll = db.get_poll_by_code(code)
+  if poll is None:
+    return "Poll not found", 404
+
+  db.delete_choice(choice_id)
+
+  return redirect(f"/manage/{code}")
+
+@app.get("/manage/<code>")
+def manage(code):
+  poll = db.get_poll_by_code(code)
+  if poll is None:
+    return validation_error("Poll not found")
+
+  last_choice_id = poll.choices[-1].id if len(poll.choices) > 0 else None
+  resp = make_response(
+    render_template("manage.html.j2",
+                    poll=poll,
+                    last_choice_id=last_choice_id))
+  resp.set_cookie(f"diddle_manage_code_{code}", "1")
+  return resp
+
+@app.post("/manage/<code>/delete")
+def delete_poll(code):
+  poll = db.get_poll_by_code(code)
+  return render_template("poll_confirm_delete.html.j2", poll=poll)
+
+@app.post("/manage/<code>/confirm_delete")
+def confirm_delete_poll(code):
+  db.delete_poll(code)
+  resp = make_response(redirect("/"))
+  resp.set_cookie(f"diddle_manage_code_{code}", "", expires=0)
+  return resp
+
+@app.post("/options/toggle_display_mode")
+def toggle_display_mode():
+  poll_id = request.form["poll_id"]
+  redirect_url = f"/poll/{poll_id}"
+  display_mode = request.cookies.get("diddle_display_mode", "table")
+  if display_mode == "table":
+    display_mode = "list"
+  else:
+    display_mode = "table"
+
+  resp = make_response(redirect(redirect_url))
+  resp.set_cookie("diddle_display_mode", display_mode)
+  return resp
diff --git a/apply_migrations.py b/apply_migrations.py
new file mode 100644
index 0000000..4ade81e
--- /dev/null
+++ b/apply_migrations.py
@@ -0,0 +1,25 @@
+from dotenv import load_dotenv
+load_dotenv()
+
+import os
+import db
+
+migrations_dir = 'migrations'  # Relative directory path
+
+# Get all migration files
+migration_files = sorted(os.listdir(migrations_dir))
+
+# Apply migrations in alphabetical order
+for migration_file in migration_files:
+  migration_path = os.path.join(migrations_dir, migration_file)
+  print(f"* Applying migration: {migration_path}")
+
+  with open(migration_path, 'r') as f:
+    migration_sql = f.read()
+
+  print(migration_sql)
+
+  db.apply_migration(migration_sql)
+  print(f"* Migration applied: {migration_path}")
+
+print(f"* {len(migration_files)} migrations applied.")
diff --git a/compose.yml b/compose.yml
new file mode 100644
index 0000000..7fae4b0
--- /dev/null
+++ b/compose.yml
@@ -0,0 +1,31 @@
+services:
+  db:
+    image: postgres:14
+    environment:
+      POSTGRES_DB: db
+      POSTGRES_USER: postgres
+      POSTGRES_PASSWORD: postgres
+    ports:
+      - "54321:5432"
+    volumes:
+      - db-data:/var/lib/postgresql/data
+    healthcheck:
+      test: ['CMD-SHELL', 'pg_isready -U postgres']
+      interval: 5s
+      timeout: 5s
+      retries: 5
+
+  web:
+    build: .
+    environment:
+      BASE_URL: http://localhost:8000
+      DB_PASSWORD: postgres
+      DB_HOST: db
+    ports:
+      - "8000:8000"
+    depends_on:
+      db:
+        condition: service_healthy
+
+volumes:
+  db-data:
diff --git a/db.py b/db.py
new file mode 100644
index 0000000..694f53d
--- /dev/null
+++ b/db.py
@@ -0,0 +1,286 @@
+import os
+from dataclasses import dataclass
+import datetime
+import psycopg2
+
+BASE_URL = os.environ["BASE_URL"]
+
+class DbContextManager:
+  def __init__(self, db: "Db"):
+    self.db = db
+
+  def __enter__(self):
+    self.cursor = self.db.get_cursor()
+    return (self.db.conn, self.cursor)
+
+  def __exit__(self, exc_type, exc_val, exc_tb):
+    if self.cursor:
+      self.cursor.close()
+    # Return False to propagate exceptions, True to suppress them
+    return False
+
+class Db:
+  MAX_RETRIES = 5
+
+  def __init__(self):
+    self.connect()
+
+  def connect(self):
+    self.conn = psycopg2.connect(
+      host=os.getenv('DB_HOST', 'localhost'),
+      database=os.getenv('DB_DATABASE', 'postgres'),
+      port=os.getenv('DB_PORT', '5432'),
+      user=os.getenv('DB_USER', 'postgres'),
+      password=os.environ['DB_PASSWORD'])
+
+  def get_cursor(self):
+    for _ in range(self.MAX_RETRIES):
+      try:
+        return self.conn.cursor()
+      except psycopg2.OperationalError:
+        self.connect()
+
+    raise Exception(f"Failed to connect to database after {Db.MAX_RETRIES} retries.")
+
+  def cursor(self):
+    return DbContextManager(db=self)
+
+db = Db()
+
+@dataclass
+class Vote:
+  id: str
+  poll_id: str
+  choice_id: str
+  voter_name: str
+
+@dataclass
+class Choice:
+  id: str
+  poll_id: str
+  start_datetime: datetime.datetime
+  end_datetime: datetime.datetime
+  votes: list[Vote]
+
+  def start_datetime_notz(self):
+    return self.start_datetime.replace(tzinfo=None)
+
+  def end_datetime_notz(self):
+    return self.end_datetime.replace(tzinfo=None)
+
+@dataclass
+class Poll:
+  id: str
+  title: str
+  description: str | None
+  pub_date: datetime.datetime
+  author_name: str
+  author_email: str | None
+  choices: list[Choice]
+  manage_code: str
+
+  def share_url(self):
+    return f"{BASE_URL}/poll/{self.id}"
+
+  def manage_url(self):
+    return f"{BASE_URL}/manage/{self.manage_code}"
+
+def tuple_to_poll(poll_t: tuple) -> Poll:
+  return Poll(
+    id=poll_t[0],
+    title=poll_t[1],
+    description=poll_t[2],
+    pub_date=poll_t[3],
+    author_name=poll_t[4],
+    author_email=poll_t[5],
+    manage_code=poll_t[6],
+    choices=[]
+  )
+
+def tuple_to_choice(choice_t: tuple) -> Choice:
+  return Choice(
+    id=choice_t[0],
+    poll_id=choice_t[1],
+    start_datetime=choice_t[2],
+    end_datetime=choice_t[3],
+    votes=[]
+  )
+
+def tuple_to_vote(vote_t: tuple) -> Vote:
+  return Vote(
+    id=vote_t[0],
+    poll_id=vote_t[1],
+    choice_id=vote_t[2],
+    voter_name=vote_t[3],
+  )
+
+def get_poll(id: str):
+  with db.cursor() as (conn, cur):
+    try:
+      cur.execute("SELECT * FROM polls WHERE id = %s", (id,))
+      poll_t = cur.fetchone()
+      if poll_t is None:
+        return None
+
+      poll = tuple_to_poll(poll_t)
+      cur.execute("SELECT * FROM choices "
+                  "WHERE poll_id = %s "
+                  "ORDER BY start_datetime", (id,))
+      choice_ts = cur.fetchall()
+
+      cur.execute("SELECT * FROM votes "
+                  "WHERE poll_id = %s "
+                  "ORDER BY voter_name", (id,))
+      vote_ts = cur.fetchall()
+
+      for choice_t in choice_ts:
+        choice = tuple_to_choice(choice_t)
+
+        for vote_t in vote_ts:
+          vote = tuple_to_vote(vote_t)
+          if vote.choice_id == choice.id:
+            choice.votes.append(vote)
+
+        poll.choices.append(choice)
+
+      conn.commit()
+      return poll
+    except Exception as e:
+      conn.rollback()
+      raise e
+
+def create_poll(title: str,
+                description: str,
+                author_name: str,
+                author_email: str,
+                choices: list[Choice]):
+
+  with db.cursor() as (conn, cur):
+    try:
+      cur.execute("INSERT INTO polls (title, description, author_name, author_email)"
+                  "VALUES (%s, %s, %s, %s) RETURNING *",
+                  (title, description, author_name, author_email))
+      poll_t = cur.fetchone()
+
+      if poll_t is None:
+        raise Exception("Failed to create poll")
+
+      poll = tuple_to_poll(poll_t)
+
+      for choice in choices:
+        cur.execute("INSERT INTO choices (poll_id, start_datetime, end_datetime)"
+                    "VALUES (%s, %s, %s)",
+                    (poll.id, choice.start_datetime, choice.end_datetime))
+
+      conn.commit()
+      return poll
+    except Exception as e:
+      conn.rollback()
+      raise e
+
+def vote_poll(poll_id: str, voter_name: str, choice_ids: list[str]):
+  with db.cursor() as (conn, cur):
+    try:
+      for choice_id in choice_ids:
+        cur.execute("INSERT INTO votes (poll_id, voter_name, choice_id)"
+                    "VALUES (%s, %s, %s)",
+                    (poll_id, voter_name, choice_id))
+
+      conn.commit()
+    except Exception as e:
+      conn.rollback()
+      raise e
+
+def apply_migration(migration_sql: str) -> None:
+  with db.cursor() as (conn, cur):
+    try:
+      cur.execute(migration_sql)
+      conn.commit()
+    except Exception as e:
+      conn.rollback()
+      raise e
+
+def get_poll_by_code(code: str) -> Poll | None:
+  with db.cursor() as (conn, cur):
+    try:
+      cur.execute("SELECT id FROM polls WHERE manage_code = %s", (code,))
+      poll_t = cur.fetchone()
+      if poll_t is None:
+        return None
+
+      poll = get_poll(poll_t[0])
+      conn.commit()
+      return poll
+    except Exception as e:
+      conn.rollback()
+      raise e
+
+def update_poll_info(
+    code,
+    title,
+    description,
+    author_name,
+    author_email,
+  ) -> None:
+  with db.cursor() as (conn, cur):
+    try:
+      cur.execute("UPDATE polls SET title = %s, description = %s, author_name = %s, author_email = %s "
+                  "WHERE manage_code = %s",
+                  (title, description, author_name, author_email, code))
+      conn.commit()
+    except Exception as e:
+      conn.rollback()
+      raise e
+
+def add_choice_to_poll(
+    code,
+    start_datetime,
+    end_datetime,
+  ) -> None:
+  poll = get_poll_by_code(code)
+  if poll is None:
+    raise Exception(f"Poll not found for code: {code}")
+
+  with db.cursor() as (conn, cur):
+    try:
+      cur.execute("INSERT INTO choices (poll_id, start_datetime, end_datetime)"
+                  "VALUES (%s, %s, %s)",
+                  (poll.id, start_datetime, end_datetime))
+      conn.commit()
+    except Exception as e:
+      conn.rollback()
+      raise e
+
+def delete_choice(choice_id: str) -> None:
+  with db.cursor() as (conn, cur):
+    try:
+      cur.execute("DELETE FROM choices WHERE id = %s", (choice_id,))
+      cur.execute("DELETE FROM votes WHERE choice_id = %s", (choice_id,))
+      conn.commit()
+    except Exception as e:
+      conn.rollback()
+      raise e
+
+def get_polls_by_codes(codes: list[str]) -> list[Poll]:
+  with db.cursor() as (conn, cur):
+    try:
+      codes_t = tuple(codes)
+      cur.execute("SELECT * FROM polls WHERE manage_code IN %s"
+                  "ORDER BY pub_date DESC", (codes_t,))
+      poll_ts = cur.fetchall()
+      polls = [tuple_to_poll(poll_t) for poll_t in poll_ts]
+
+      conn.commit()
+      return polls
+    except Exception as e:
+      conn.rollback()
+      raise e
+
+def delete_poll(code: str) -> None:
+  with db.cursor() as (conn, cur):
+    try:
+      cur.execute("DELETE FROM polls WHERE manage_code = %s", (code,))
+      conn.commit()
+    except Exception as e:
+      conn.rollback()
+      raise e
diff --git a/migrations/0000_initial.sql b/migrations/0000_initial.sql
new file mode 100644
index 0000000..8e9f1ae
--- /dev/null
+++ b/migrations/0000_initial.sql
@@ -0,0 +1,28 @@
+CREATE EXTENSION IF NOT EXISTS "uuid-ossp";
+
+CREATE TABLE IF NOT EXISTS polls (
+    id uuid PRIMARY KEY DEFAULT uuid_generate_v4(),
+    title TEXT NOT NULL,
+    description TEXT,
+    pub_date TIMESTAMP WITH TIME ZONE NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    author_name TEXT NOT NULL,
+    author_email TEXT,
+    manage_code uuid DEFAULT uuid_generate_v4()
+);
+
+CREATE TABLE IF NOT EXISTS choices (
+    id uuid PRIMARY KEY DEFAULT uuid_generate_v4(),
+    poll_id uuid NOT NULL,
+    start_datetime TIMESTAMP NOT NULL,
+    end_datetime TIMESTAMP NOT NULL,
+    FOREIGN KEY (poll_id) REFERENCES polls (id) ON DELETE CASCADE
+);
+
+CREATE TABLE IF NOT EXISTS votes (
+    id uuid PRIMARY KEY DEFAULT uuid_generate_v4(),
+    poll_id uuid NOT NULL,
+    choice_id uuid NOT NULL,
+    voter_name TEXT NOT NULL,
+    FOREIGN KEY (choice_id) REFERENCES choices (id) ON DELETE CASCADE,
+    FOREIGN KEY (poll_id) REFERENCES polls (id) ON DELETE CASCADE
+);
diff --git a/migrations/0001_indices.sql b/migrations/0001_indices.sql
new file mode 100644
index 0000000..42007ee
--- /dev/null
+++ b/migrations/0001_indices.sql
@@ -0,0 +1,3 @@
+CREATE INDEX IF NOT EXISTS idx_votes_poll_id_voter_name ON votes (poll_id, voter_name);
+CREATE INDEX IF NOT EXISTS idx_choices_poll_id_start_datetime ON choices (poll_id, start_datetime);
+CREATE INDEX IF NOT EXISTS idx_votes_choice_id ON votes (choice_id);
diff --git a/requirements.txt b/requirements.txt
new file mode 100644
index 0000000..a1b0023
--- /dev/null
+++ b/requirements.txt
@@ -0,0 +1,11 @@
+blinker==1.7.0
+click==8.1.7
+Flask==3.0.2
+gunicorn==21.2.0
+itsdangerous==2.1.2
+Jinja2==3.1.3
+MarkupSafe==2.1.5
+packaging==23.2
+psycopg2-binary==2.9.9
+python-dotenv==1.0.1
+Werkzeug==3.0.1
diff --git a/scripts/container_entrypoint.sh b/scripts/container_entrypoint.sh
new file mode 100755
index 0000000..9f8dcf2
--- /dev/null
+++ b/scripts/container_entrypoint.sh
@@ -0,0 +1,5 @@
+#!/bin/sh
+set -euxo pipefail
+
+python apply_migrations.py
+gunicorn --bind "0.0.0.0:8000" -w 4 app:app
diff --git a/static/styles.css b/static/styles.css
new file mode 100644
index 0000000..e34660b
--- /dev/null
+++ b/static/styles.css
@@ -0,0 +1,133 @@
+html {
+  font-family: "Helvetica Neue", "Arial", sans-serif;
+  font-size: 16px;
+}
+
+body {
+  padding: 10px;
+  max-width: 1000px;
+  margin: 0 auto;
+}
+
+button,
+input[type="submit"] {
+  cursor: pointer;
+  font-size: 16px;
+  border-radius: 4px;
+  text-shadow: none;
+  box-shadow: none;
+  padding: 5px 8px;
+  border: 0;
+  background-color: rgb(63, 122, 248);
+  color: white;
+}
+
+button.red,
+input[type="submit"].red {
+  background-color: #d42f2f;
+}
+
+button.green,
+input[type="submit"].green {
+  background-color: #4caf50;
+}
+
+button.yellow,
+input[type="submit"].yellow {
+  background-color: #ff9800;
+}
+
+input[type="text"],
+input[type="datetime-local"] {
+  font-size: 16px;
+  color: black;
+}
+
+input[type="text"]:disabled,
+input[type="datetime-local"]:disabled {
+  color: #666;
+}
+
+.contrast {
+  color: #fa8e35;
+}
+
+th, td {
+  padding-left: 0;
+  padding-right: 5px;
+  min-width: 100px;
+}
+
+table {
+  margin-left: -2px;
+}
+
+.vote-table th,
+.vote-table td {
+  text-align: center;
+  padding: 7px 5px;
+}
+
+.vote-table th span {
+  display: block;
+}
+
+.vote-table th span i {
+  font-weight: normal;
+}
+
+.vote-table td:first-child {
+  text-align: left;
+  padding-left: 5px;
+}
+
+.vote-table tr:last-child td:first-child {
+  padding-left: 0;
+}
+
+.vote-table tr td:nth-child(even),
+.vote-table tr th:nth-child(even) {
+  background-color: #f2f2f2; /* Light grey background */
+}
+
+.vote-table tr:nth-child(even),
+.vote-table tr:nth-child(even) {
+  background-color: #f8f6ff; /* Light grey background */
+}
+
+.danger-zone {
+  margin-top: 40px;
+}
+
+.manage-table th {
+  text-align: left;
+}
+
+.poll-form td:last-child,
+.manage-table td:last-child {
+  display: flex;
+  flex-flow: row;
+  align-items: center;
+}
+
+.poll-form td:last-child > *,
+.manage-table td:last-child > * {
+  flex: 1;
+}
+
+.manage-table td:last-child input[type="submit"] {
+  max-width: 70px;
+}
+
+.display-mode-section {
+  margin-bottom: 30px;
+}
+
+.display-mode-section input[type="submit"] {
+  margin-left: 10px;
+}
+
+.vote-list label,
+input[type="checkbox"] {
+  cursor: pointer;
+}
diff --git a/templates/base.html.j2 b/templates/base.html.j2
new file mode 100644
index 0000000..066c39e
--- /dev/null
+++ b/templates/base.html.j2
@@ -0,0 +1,13 @@
+<!DOCTYPE html>
+<html>
+<head>
+    <title>diddle 👉👈</title>
+    <meta charset="utf-8">
+    <meta name="viewport" content="width=device-width, initial-scale=1, user-scalable=no">
+    <link rel="stylesheet" href="/static/styles.css"></link>
+</head>
+<body>
+  <h1><a href="/">diddle 👉👈</a></h1>
+  {% block content %}{% endblock %}
+</body>
+</html>
diff --git a/templates/error.html.j2 b/templates/error.html.j2
new file mode 100644
index 0000000..2d0dc19
--- /dev/null
+++ b/templates/error.html.j2
@@ -0,0 +1,6 @@
+{% extends "base.html.j2" %}
+
+{% block content %}
+<h2>Error</h2>
+{{ error }}
+{% endblock %}
diff --git a/templates/index.html.j2 b/templates/index.html.j2
new file mode 100644
index 0000000..f84b428
--- /dev/null
+++ b/templates/index.html.j2
@@ -0,0 +1,40 @@
+{% extends "base.html.j2" %}
+
+{% block content %}
+<h2>Create new diddle</h2>
+<form class="poll-form" action="/poll/create" method="post">
+  <table>
+    <tbody>
+      <tr>
+        <td><label for="title">Title</label></td>
+        <td><input type="text" name="title" required></td>
+      </tr>
+      <tr>
+        <td><label for="description">Description (optional)</label></td>
+        <td><textarea name="description"></textarea></td>
+      </tr>
+      <tr>
+        <td><label for="author_name">Your name</label></td>
+        <td><input type="text" name="author_name" required></td>
+      </tr>
+      <tr>
+        <td><label for="author_email">Your email (optional)</label></td>
+        <td><input type="text" name="author_email"></td>
+      </tr>
+    </tbody>
+  </table>
+
+  <p>You can add options after submitting.</p>
+  <input class="green" type="submit" value="Create">
+</form>
+
+{% if created_polls | length != 0 %}
+<h3>My diddles</h3>
+<ul>
+  {% for poll in created_polls %}
+  <li><a href="/manage/{{ poll.manage_code }}">{{ poll.title }}</a></li>
+  {% endfor %}
+</ul>
+{% endif %}
+
+{% endblock %}
diff --git a/templates/manage.html.j2 b/templates/manage.html.j2
new file mode 100644
index 0000000..82f67ea
--- /dev/null
+++ b/templates/manage.html.j2
@@ -0,0 +1,119 @@
+{% extends "base.html.j2" %}
+
+{% block content %}
+
+<h2>Managing poll <span class="contrast">{{ poll.title }}</span> by <i>{{ poll.author_name }}</i></h2>
+
+<p>
+  Share this URL with your peers:<br>
+  <a href="{{ poll.share_url() }}">{{ poll.share_url() }}</a>
+</p>
+<p>
+  <strong>Note!</strong> You can only edit this poll if you have this URL or use the same browser session:<br>
+  <a href="{{ poll.manage_url() }}">{{ poll.manage_url() }}</a>
+</p>
+
+<form class="poll-form" action="/manage/{{ poll.manage_code }}/update_info" method="post">
+  <table>
+    <tbody>
+      <tr>
+        <td><label for="title">Title</label></td>
+        <td><input type="text" name="title" value="{{ poll.title }}" required></td>
+      </tr>
+      <tr>
+        <td><label for="description">Description (optional)</label></td>
+        <td><textarea name="description" value="{{ poll.description }}"></textarea></td>
+      </tr>
+      <tr>
+        <td><label for="author_name">Your name</label></td>
+        <td><input type="text" name="author_name" value="{{ poll.author_name }}" required></td>
+      </tr>
+      <tr>
+        <td><label for="author_email">Your email (optional)</label></td>
+        <td><input type="text" name="author_email" value="{{ poll.author_email }}"></td>
+      </tr>
+    </tbody>
+  </table>
+  <br>
+  <input type="submit" value="Update">
+</form>
+
+<div>
+  <h3>Options</h3>
+</div>
+
+<table class="manage-table">
+  <thead>
+    <tr>
+      <th>Start time</th>
+      <th>End time</th>
+      <th></th>
+    </tr>
+  </thead>
+  <tbody>
+    {% for choice in poll.choices %}
+    <form action="/manage/{{ poll.manage_code }}/delete_choice/{{ choice.id }}" method="post">
+      <tr>
+        <td>
+          <input type="datetime-local" name="start_datetime_{{ choice.id }}" value="{{ choice.start_datetime_notz() }}" disabled
+                 {% if last_choice_id == choice.id %}id="last-start-datetime"{% endif %}>
+        </td>
+        <td>
+          <input type="datetime-local" name="end_datetime_{{ choice.id }}" value="{{ choice.end_datetime_notz() }}" disabled
+                 {% if last_choice_id == choice.id %}id="last-end-datetime"{% endif %}>
+        </td>
+        <td>
+          <input class="red" type="submit" value="Delete">
+        </td>
+      </tr>
+    </form>
+    {% endfor %}
+    <form action="/manage/{{ poll.manage_code }}/add_choice" method="post">
+      <tr>
+        <td>
+          <input type="datetime-local" name="start_datetime" required>
+        </td>
+        <td>
+          <input type="datetime-local" name="end_datetime" required>
+        </td>
+        <td>
+          <input class="green" type="submit" value="Add">
+        </td>
+      </tr>
+    </form>
+  </tbody>
+</table>
+
+<div class="danger-zone">
+  <h3>Danger zone</h3>
+  <form action="/manage/{{ poll.manage_code }}/delete" method="post">
+    <!-- Empty forms make Lynx use HTTP method GET incorrectly, so we add a useless field -->
+    <input type="hidden" name="poll_id" value="{{ poll.id }}">
+    <input class="red" type="submit" value="Delete poll">
+  </form>
+</div>
+
+<script>
+const hour = 1000 * 60 * 60;
+
+const startDatetimeInput = document.querySelector('input[name="start_datetime"]');
+const endDatetimeInput = document.querySelector('input[name="end_datetime"]');
+
+const lastStartDatetimeInput = document.getElementById('last-start-datetime');
+const lastEndDatetimeInput = document.getElementById('last-end-datetime');
+
+if (lastStartDatetimeInput !== null && startDatetimeInput.valueAsDate === null) {
+  startDatetimeInput.valueAsDate = new Date(lastStartDatetimeInput.valueAsDate.getTime() + hour);
+}
+
+startDatetimeInput.addEventListener('blur', onStartDatetimeBlur);
+
+function onStartDatetimeBlur(event) {
+  const endDatetimeInput = document.querySelector('input[name="end_datetime"]');
+  if (endDatetimeInput.valueAsDate === null) {
+    endDatetimeInput.valueAsDate = new Date(event.target.valueAsDate.getTime() + hour);
+  }
+}
+</script>
+
+{% endblock %}
\ No newline at end of file
diff --git a/templates/poll.html.j2 b/templates/poll.html.j2
new file mode 100644
index 0000000..e0ede1f
--- /dev/null
+++ b/templates/poll.html.j2
@@ -0,0 +1,34 @@
+{% extends "base.html.j2" %}
+
+{% block content %}
+
+<h2><span class="contrast">{{ poll.title }}</span> by <i>{{ poll.author_name }}</i></h2>
+{% if poll.description %}
+  <p>{{ poll.description }}</p>
+{% endif %}
+
+{% if poll.choices | length  == 0 %}
+<p>No options available.</p>
+{% else %}
+
+<div class="display-mode-section">
+  <form action="/options/toggle_display_mode" method="post">
+    <input type="hidden" name="poll_id" value="{{ poll.id }}">
+    <label>
+      Display mode: <strong>{{ display_mode }}</strong>
+      <input type="submit" value="Toggle">
+    </label>
+  </form>
+</div>
+
+<form action="/poll/{{ poll.id }}/vote" method="post">
+  {% if display_mode == "table" %}
+  {% include "poll_vote_table.html.j2" %}
+  {% else %}
+  {% include "poll_vote_list.html.j2" %}
+  {% endif %}
+</form>
+{% endif %}
+
+
+{% endblock %}
diff --git a/templates/poll_confirm_delete.html.j2 b/templates/poll_confirm_delete.html.j2
new file mode 100644
index 0000000..3a6bc83
--- /dev/null
+++ b/templates/poll_confirm_delete.html.j2
@@ -0,0 +1,13 @@
+{% extends "base.html.j2" %}
+
+{% block content %}
+<h2>Confirm deletion of <span class="contrast">{{ poll.title }}</span></h2>
+
+<p>Are you sure you want to delete {{ poll.title }}?</p>
+
+<form action="/manage/{{ poll.manage_code }}/confirm_delete" method="post">
+  <!-- Empty forms make Lynx use HTTP method GET incorrectly, so we add a useless field -->
+  <input type="hidden" name="poll_id" value="{{ poll.id }}">
+  <input class="red" type="submit" value="Yes, delete it">
+</form>
+{% endblock %}
diff --git a/templates/poll_vote_list.html.j2 b/templates/poll_vote_list.html.j2
new file mode 100644
index 0000000..37b9406
--- /dev/null
+++ b/templates/poll_vote_list.html.j2
@@ -0,0 +1,34 @@
+<div class="vote-list">
+  {% for choice in choices %}
+  <div>
+    <label for="choice_{{ choice.id }}">
+      <input type="checkbox" name="choice_{{ choice.id }}" id="choice_{{ choice.id }}">
+      <strong>
+        {{ choice.start_datetime.strftime("%a %d.%m") }}
+        <span>
+          {% if now.year != choice.start_datetime.year %}.{{choice.start_datetime.year}}{% endif %}
+        </span>
+        <span>
+          {{ choice.start_datetime.strftime("%H:%M") }} &ndash; {{ choice.end_datetime.strftime("%H:%M") }}
+        </span>
+      </strong>
+      <span>
+        <i>{{ choice.votes | length }} votes</i>
+      </span>
+      <div>
+        {% if choice.votes | length != 0 %}
+        Voted by: {% for vote in choice.votes %}{{ vote.voter_name }}{% if not loop.last %}, {% endif %}{% endfor %}
+        {% endif %}
+      <div>
+    </label>
+  </div>
+  <p></p>
+  {% endfor %}
+</div>
+
+<div>
+  <label for="voter_name" hidden>Your name</label>
+  <input type="text" name="voter_name" placeholder="Your name" required>
+  <input class="green" type="submit" value="Submit">
+</div>
+
diff --git a/templates/poll_vote_table.html.j2 b/templates/poll_vote_table.html.j2
new file mode 100644
index 0000000..bfba968
--- /dev/null
+++ b/templates/poll_vote_table.html.j2
@@ -0,0 +1,51 @@
+<table class="vote-table">
+  <tr>
+    <th></th>
+    {% for choice in choices %}
+    <th>
+      {{ choice.start_datetime.strftime("%a %d.%m") }}
+      <span>
+        {% if now.year != choice.start_datetime.year %}.{{choice.start_datetime.year}}{% endif %}
+      </span>
+      <span>
+        {{ choice.start_datetime.strftime("%H:%M") }} &ndash; {{ choice.end_datetime.strftime("%H:%M") }}
+      </span>
+      <span>
+        <i>{{ choice.votes | length }} votes</i>
+      </span>
+    </th>
+    {% endfor %}
+  </tr>
+  {% for voter in choices_by_voter %}
+  <tr>
+    <td>{{ voter.name }}</td>
+    {% for voted in voter.votes %}
+    {% if voted %}
+    <td>
+      <input type="checkbox" checked disabled>
+    </td>
+    {% else %}
+    <td>
+      <input type="checkbox" disabled>
+    </td>
+    {% endif %}
+    {% endfor %}
+  </tr>
+  {% endfor %}
+
+  <!-- Add a row for the current user -->
+  <tr>
+    <td>
+      <label for="voter_name" hidden>Your name</label>
+      <input type="text" name="voter_name" placeholder="Your name" required>
+    </td>
+    {% for choice in choices %}
+    <td>
+      <input type="checkbox" name="choice_{{ choice.id }}">
+    </td>
+    {% endfor %}
+  </tr>
+  <!-- End of the row for the current user -->
+</table>
+
+<input class="green" type="submit" value="Submit">