latijnspellen/reaction_game.html at main · jwburssens/latijnspellen · GitHub

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<!doctype html>
<html lang="en">
  <head>
    <meta charset="utf-8" />
    <meta name="viewport" content="width=device-width, initial-scale=1" />
    <title>Latin Reaction Game</title>
    <style>
      body {
        font-family: Arial, sans-serif;
        max-width: 1100px;
        margin: 2rem auto;
        padding: 0 1rem;
      }
      h1 {
        margin-bottom: 0.5rem;
      }
      .muted {
        color: #666;
      }
      .selectors {
        display: grid;
        gap: 0.75rem;
        grid-template-columns: repeat(4, minmax(0, 1fr));
        margin: 1rem 0;
      }
      @media (max-width: 900px) {
        .selectors {
          grid-template-columns: 1fr;
        }
      }
      label {
        display: block;
        font-weight: 600;
        margin-bottom: 0.35rem;
      }
      select,
      button {
        font: inherit;
        width: 100%;
        padding: 0.55rem;
      }
      .actions {
        display: flex;
        gap: 0.75rem;
        margin-bottom: 1rem;
      }
      .actions button {
        width: auto;
        cursor: pointer;
      }
      .status {
        margin-bottom: 0.75rem;
      }
      .error {
        color: #b00020;
      }
      .stats {
        margin-bottom: 0.75rem;
        font-weight: 600;
      }
      .highscores {
        margin-bottom: 0.9rem;
        border: 1px solid #d8d8d8;
        border-radius: 8px;
        background: #fafafa;
        padding: 0.75rem;
      }
      .highscores h2 {
        margin: 0 0 0.4rem 0;
        font-size: 1rem;
      }
      .highscores ol {
        margin: 0;
        padding-left: 1.2rem;
      }
      .highscores li {
        margin: 0.2rem 0;
      }
      .game-wrap {
        position: relative;
        border: 1px solid #d8d8d8;
        border-radius: 10px;
        background: #f8f8f8;
        min-height: 520px;
        overflow: hidden;
      }
      .playfield {
        position: relative;
        height: 420px;
        overflow: hidden;
      }
      .falling-word {
        position: absolute;
        transform: translateX(-50%);
        border: 1px solid #cfcfcf;
        border-radius: 999px;
        background: #ffffff;
        padding: 0.35rem 0.75rem;
        width: auto;
        max-width: 80%;
        cursor: pointer;
        white-space: nowrap;
        user-select: none;
      }
      .falling-word:hover {
        background: #f0f0f0;
      }
      .prompt {
        border-top: 1px solid #dedede;
        background: #efefef;
        padding: 0.9rem 1rem;
      }
      .prompt .label {
        font-size: 0.92rem;
        color: #555;
      }
      .prompt .word {
        font-size: 1.45rem;
        font-weight: 700;
        margin-top: 0.25rem;
      }
      .hint {
        margin-top: 0.25rem;
        color: #666;
      }
    </style>
  </head>
  <body>
    <h1>Latin Reaction Game</h1>
    <p><a id="backLink" href="index.html">← Back to index</a></p>
    <p class="muted">
      A prompt appears at the bottom. Click the matching dropping word before it
      vanishes.
    </p>

    <div class="selectors">
      <div>
        <label for="schoolSelect">School</label>
        <select id="schoolSelect" disabled>
          <option>Loading...</option>
        </select>
      </div>
      <div>
        <label for="yearSelect">Year</label>
        <select id="yearSelect" disabled>
          <option>Select school first</option>
        </select>
      </div>
      <div>
        <label for="chapterSelect">Chapter</label>
        <select id="chapterSelect" disabled>
          <option>Select year first</option>
        </select>
      </div>
      <div>
        <label for="sectionSelect">Section</label>
        <select id="sectionSelect" disabled>
          <option>Select chapter first</option>
        </select>
      </div>
      <div>
        <label for="scopeSelect">Play scope</label>
        <select id="scopeSelect">
          <option value="section" selected>Selected section</option>
          <option value="chapter">Whole chapter</option>
        </select>
      </div>
    </div>

    <div class="actions">
      <button type="button" id="startBtn" disabled>Start game</button>
      <button type="button" id="stopBtn" disabled>Stop</button>
    </div>

    <div id="status" class="status muted"></div>
    <div id="stats" class="stats"></div>
    <section class="highscores" aria-live="polite">
      <h2>Top 3 Highscores</h2>
      <ol id="highscoresList">
        <li>-</li>
      </ol>
    </section>

    <section class="game-wrap" aria-live="polite">
      <div id="playfield" class="playfield"></div>
      <div class="prompt">
        <div class="label" id="promptLabel">Prompt</div>
        <div class="word" id="promptWord">-</div>
        <div class="hint">Click the matching Dutch translation above.</div>
      </div>
    </section>

    <script>
      const API_URL = "api/section_words.php";

      const schoolSelect = document.getElementById("schoolSelect");
      const yearSelect = document.getElementById("yearSelect");
      const chapterSelect = document.getElementById("chapterSelect");
      const sectionSelect = document.getElementById("sectionSelect");
      const scopeSelect = document.getElementById("scopeSelect");
      const startBtn = document.getElementById("startBtn");
      const stopBtn = document.getElementById("stopBtn");
      const backLink = document.getElementById("backLink");
      const status = document.getElementById("status");
      const stats = document.getElementById("stats");
      const highscoresList = document.getElementById("highscoresList");
      const playfield = document.getElementById("playfield");
      const promptLabel = document.getElementById("promptLabel");
      const promptWord = document.getElementById("promptWord");
      const GAME_KEY = "reaction";

      let structure = null;
      let wordPairs = [];
      let currentPair = null;
      let particles = [];
      let score = 0;
      let misses = 0;
      let running = false;
      let lastFrameTime = 0;
      let spawnAccumulator = 0;
      let animationFrameId = 0;
      let activePromptVersion = 0;
      let highscores = [];

      function setStatus(text, isError = false) {
        status.textContent = text;
        status.className = isError ? "status error" : "status muted";
      }

      function fillSelect(selectEl, items, placeholder) {
        selectEl.innerHTML = "";

        if (!items.length) {
          const option = document.createElement("option");
          option.value = "";
          option.textContent = placeholder;
          selectEl.appendChild(option);
          selectEl.disabled = true;
          return;
        }

        const chooseOption = document.createElement("option");
        chooseOption.value = "";
        chooseOption.textContent = "Choose...";
        selectEl.appendChild(chooseOption);

        items.forEach((item) => {
          const option = document.createElement("option");
          option.value = item;
          option.textContent = item;
          selectEl.appendChild(option);
        });

        selectEl.disabled = false;
      }

      function sortedKeys(obj) {
        return Object.keys(obj || {}).sort((a, b) =>
          a.localeCompare(b, undefined, { sensitivity: "base", numeric: true }),
        );
      }

      function updateStats() {
        const speedMultiplier = getSpeedMultiplier().toFixed(2);
        stats.textContent = `Score: ${score} | Misses: ${misses} | Speed x${speedMultiplier}`;
      }

      function currentSelection() {
        return {
          school: schoolSelect.value,
          year: yearSelect.value,
          chapter: chapterSelect.value,
          section: sectionSelect.value,
        };
      }

      function updateStartButtonAvailability() {
        const scope = scopeSelect.value;
        const hasChapter = !!(
          schoolSelect.value &&
          yearSelect.value &&
          chapterSelect.value
        );
        if (scope === "chapter") {
          startBtn.disabled = !hasChapter;
          return;
        }

        startBtn.disabled = !(hasChapter && sectionSelect.value);
      }

      function updateBackLink() {
        const selection = currentSelection();
        const params = new URLSearchParams();

        if (selection.school) {
          params.set("school", selection.school);
        }
        if (selection.year) {
          params.set("year", selection.year);
        }
        if (selection.chapter) {
          params.set("chapter", selection.chapter);
        }
        if (selection.section) {
          params.set("section", selection.section);
        }

        backLink.href = params.toString()
          ? `index.html?${params.toString()}`
          : "index.html";
      }

      function renderHighscores() {
        highscoresList.innerHTML = "";

        if (!highscores.length) {
          highscoresList.innerHTML = "<li>No highscores yet.</li>";
          return;
        }

        highscores.forEach((entry) => {
          const li = document.createElement("li");
          const name = entry.name || "Unknown";
          const entryScore = Number(entry.score || 0);
          li.textContent = `${name} — ${entryScore}`;
          highscoresList.appendChild(li);
        });
      }

      function isTopThreeScore(candidateScore) {
        if (highscores.length < 3) {
          return true;
        }

        const lastScore = Number(highscores[highscores.length - 1].score || 0);
        return candidateScore > lastScore;
      }

      async function loadHighscores() {
        const selection = currentSelection();
        if (
          !selection.school ||
          !selection.year ||
          !selection.chapter ||
          !selection.section
        ) {
          highscores = [];
          renderHighscores();
          return;
        }

        const params = new URLSearchParams({
          action: "highscores_get",
          game: GAME_KEY,
          school: selection.school,
          year: selection.year,
          chapter: selection.chapter,
          section: selection.section,
        });

        try {
          const response = await fetch(`${API_URL}?${params.toString()}`, {
            cache: "no-store",
          });
          const data = await response.json();

          if (!response.ok || !data.ok) {
            throw new Error(data.error || `HTTP ${response.status}`);
          }

          highscores = Array.isArray(data.scores) ? data.scores : [];
          renderHighscores();
        } catch {
          highscores = [];
          renderHighscores();
        }
      }

      async function submitHighscoreIfEligible(finalScore) {
        const selection = currentSelection();
        if (
          !selection.school ||
          !selection.year ||
          !selection.chapter ||
          !selection.section
        ) {
          return;
        }

        if (!isTopThreeScore(finalScore)) {
          return;
        }

        const name = window.prompt("New top 3 score! Enter your name:", "");
        if (!name || !name.trim()) {
          return;
        }

        const params = new URLSearchParams({
          action: "highscores_add",
          game: GAME_KEY,
          school: selection.school,
          year: selection.year,
          chapter: selection.chapter,
          section: selection.section,
          name: name.trim(),
          score: String(finalScore),
        });

        try {
          const response = await fetch(`${API_URL}?${params.toString()}`, {
            cache: "no-store",
          });
          const data = await response.json();

          if (!response.ok || !data.ok) {
            throw new Error(data.error || `HTTP ${response.status}`);
          }

          highscores = Array.isArray(data.scores) ? data.scores : [];
          renderHighscores();
        } catch {
          // ignore highscore submit errors in gameplay flow
        }
      }

      function clearParticles() {
        particles.forEach((particle) => particle.el.remove());
        particles = [];
      }

      function resetGameState() {
        clearParticles();
        score = 0;
        misses = 0;
        activePromptVersion = 0;
        currentPair = null;
        promptWord.textContent = "-";
        updateStats();
      }

      function getSpeedMultiplier() {
        return 1 + score * 0.08;
      }

      function getSpawnIntervalMs() {
        const base = 1200;
        const interval = base - score * 45;
        return Math.max(350, interval);
      }

      function getDropPixelsPerSecond() {
        const base = 45;
        return base * getSpeedMultiplier();
      }

      function chooseNewPrompt() {
        if (!wordPairs.length) {
          currentPair = null;
          promptWord.textContent = "-";
          return;
        }

        const randomIndex = Math.floor(Math.random() * wordPairs.length);
        currentPair = wordPairs[randomIndex];
        activePromptVersion += 1;
        promptWord.textContent = currentPair.latin;
      }

      function createParticle(text, isCorrectWord, promptVersion) {
        const element = document.createElement("button");
        element.type = "button";
        element.className = "falling-word";
        element.textContent = text;

        const fieldWidth = playfield.clientWidth;
        const x = 24 + Math.random() * Math.max(30, fieldWidth - 48);

        element.style.left = `${x}px`;
        element.style.top = `-26px`;

        const particle = {
          el: element,
          text,
          y: -26,
          isCorrectWord,
          promptVersion,
          removed: false,
        };

        element.addEventListener("click", () => {
          if (!running || particle.removed) {
            return;
          }

          if (!currentPair) {
            return;
          }

          if (
            particle.isCorrectWord &&
            particle.promptVersion === activePromptVersion
          ) {
            score += 1;
            setStatus("Correct!", false);
            removeParticle(particle);
            chooseNewPrompt();
          } else {
            misses += 1;
            setStatus("Wrong word.", true);
            removeParticle(particle);
          }

          updateStats();

          if (misses >= 3) {
            endRound("Game over. You reached 3 misses.");
          }
        });

        playfield.appendChild(element);
        particles.push(particle);
      }

      function removeParticle(particle) {
        if (particle.removed) {
          return;
        }
        particle.removed = true;
        particle.el.remove();
      }

      function getDistractorTranslation(correctTranslation) {
        const pool = wordPairs
          .map((pair) => pair.nl)
          .filter((translation) => translation !== correctTranslation);

        if (!pool.length) {
          return correctTranslation;
        }

        const index = Math.floor(Math.random() * pool.length);
        return pool[index];
      }

      function spawnWords() {
        if (!currentPair) {
          return;
        }

        const targetFirst = Math.random() < 0.55;
        const distractorCount = 2 + Math.floor(Math.random() * 2);

        if (targetFirst) {
          createParticle(currentPair.nl, true, activePromptVersion);
        }

        for (let index = 0; index < distractorCount; index += 1) {
          const translation = getDistractorTranslation(currentPair.nl);
          createParticle(translation, false, activePromptVersion);
        }

        if (!targetFirst) {
          createParticle(currentPair.nl, true, activePromptVersion);
        }
      }

      function gameLoop(timestamp) {
        if (!running) {
          return;
        }

        if (!lastFrameTime) {
          lastFrameTime = timestamp;
        }

        const deltaMs = timestamp - lastFrameTime;
        lastFrameTime = timestamp;
        spawnAccumulator += deltaMs;

        const dropSpeed = getDropPixelsPerSecond();
        const maxY = playfield.clientHeight + 40;

        particles.forEach((particle) => {
          if (particle.removed) {
            return;
          }

          particle.y += (dropSpeed * deltaMs) / 1000;
          particle.el.style.top = `${particle.y}px`;

          if (particle.y > maxY) {
            if (
              particle.isCorrectWord &&
              particle.promptVersion === activePromptVersion
            ) {
              misses += 1;
              setStatus("Too slow, target vanished.", true);
              chooseNewPrompt();
              updateStats();

              if (misses >= 3) {
                endRound("Game over. You reached 3 misses.");
              }
            }
            removeParticle(particle);
          }
        });

        particles = particles.filter((particle) => !particle.removed);

        const spawnInterval = getSpawnIntervalMs();
        while (spawnAccumulator >= spawnInterval) {
          spawnAccumulator -= spawnInterval;
          spawnWords();
        }

        animationFrameId = requestAnimationFrame(gameLoop);
      }

      function stopGame(showMessage = true) {
        running = false;
        if (animationFrameId) {
          cancelAnimationFrame(animationFrameId);
          animationFrameId = 0;
        }
        clearParticles();
        stopBtn.disabled = true;
        if (showMessage) {
          setStatus("Game stopped.");
        }
      }

      function endRound(message) {
        if (!running) {
          return;
        }

        const finalScore = score;
        stopGame(false);
        setStatus(message);
        submitHighscoreIfEligible(finalScore);
      }

      function startGame() {
        if (wordPairs.length < 3) {
          setStatus(
            "Need at least 3 words with Dutch translations in this section.",
            true,
          );
          return;
        }

        stopGame(false);
        resetGameState();
        running = true;
        stopBtn.disabled = false;
        chooseNewPrompt();
        setStatus("Game started. Click the matching Dutch translation.");
        lastFrameTime = 0;
        spawnAccumulator = 0;
        animationFrameId = requestAnimationFrame(gameLoop);
      }

      async function loadStructure() {
        try {
          const response = await fetch(`${API_URL}?action=structure`, {
            cache: "no-store",
          });
          const data = await response.json();

          if (!response.ok || !data.ok) {
            throw new Error(data.error || `HTTP ${response.status}`);
          }

          structure = data;
          fillSelect(
            schoolSelect,
            sortedKeys(structure.schools),
            "No schools found",
          );
          fillSelect(yearSelect, [], "Select school first");
          fillSelect(chapterSelect, [], "Select year first");
          fillSelect(sectionSelect, [], "Select chapter first");
          renderHighscores();
          setStatus("Choose a section and click Start game.");
        } catch (error) {
          setStatus(`Could not load structure: ${error.message}`, true);
        }
      }

      function clearSelectionGameData() {
        stopGame(false);
        resetGameState();
        wordPairs = [];
        highscores = [];
        renderHighscores();
        startBtn.disabled = true;
      }

      function updateYears() {
        fillSelect(
          yearSelect,
          sortedKeys(structure?.schools?.[schoolSelect.value]),
          "No years found",
        );
        fillSelect(chapterSelect, [], "Select year first");
        fillSelect(sectionSelect, [], "Select chapter first");
        clearSelectionGameData();
        updateBackLink();
        updateStartButtonAvailability();
      }

      function updateChapters() {
        fillSelect(
          chapterSelect,
          sortedKeys(
            structure?.schools?.[schoolSelect.value]?.[yearSelect.value],
          ),
          "No chapters found",
        );
        fillSelect(sectionSelect, [], "Select chapter first");
        clearSelectionGameData();
        updateBackLink();
        updateStartButtonAvailability();
      }

      function updateSections() {
        fillSelect(
          sectionSelect,
          sortedKeys(
            structure?.schools?.[schoolSelect.value]?.[yearSelect.value]?.[
              chapterSelect.value
            ],
          ),
          "No sections found",
        );
        clearSelectionGameData();
        updateBackLink();
        updateStartButtonAvailability();
      }

      async function loadSectionData() {
        const school = schoolSelect.value;
        const year = yearSelect.value;
        const chapter = chapterSelect.value;
        const section = sectionSelect.value;
        const scope = scopeSelect.value;

        if (!school || !year || !chapter || (scope === "section" && !section)) {
          setStatus(
            scope === "chapter"
              ? "Please choose school, year and chapter."
              : "Please choose school, year, chapter and section.",
            true,
          );
          return;
        }

        stopGame(false);
        resetGameState();

        setStatus("Loading section words...");

        try {
          const sectionsToLoad =
            scope === "chapter"
              ? sortedKeys(structure?.schools?.[school]?.[year]?.[chapter])
              : [section];

          const sectionResponses = await Promise.all(
            sectionsToLoad.map(async (sectionName) => {
              const params = new URLSearchParams({
                action: "section",
                school,
                year,
                chapter,
                section: sectionName,
              });

              const response = await fetch(`${API_URL}?${params.toString()}`, {
                cache: "no-store",
              });
              const data = await response.json();

              if (!response.ok || !data.ok) {
                throw new Error(data.error || `HTTP ${response.status}`);
              }

              return data;
            }),
          );

          const combinedMap = new Map();
          sectionResponses.forEach((data) => {
            data.words.forEach((entry) => {
              if (!entry.found || !entry.attributes || !entry.attributes.nl) {
                return;
              }

              if (!combinedMap.has(entry.latin)) {
                combinedMap.set(entry.latin, {
                  latin: entry.latin,
                  nl: entry.attributes.nl,
                });
              }
            });
          });

          wordPairs = Array.from(combinedMap.values());

          if (wordPairs.length < 3) {
            startBtn.disabled = true;
            setStatus(
              "Need at least 3 words with translations for this game.",
              true,
            );
            return;
          }

          startBtn.disabled = false;
          setStatus(
            scope === "chapter"
              ? `Loaded ${wordPairs.length} words from whole chapter. Click Start game.`
              : `Loaded ${wordPairs.length} words. Click Start game.`,
          );
          await loadHighscores();
          startGame();
        } catch (error) {
          startBtn.disabled = true;
          setStatus(`Could not load section: ${error.message}`, true);
        }
      }

      schoolSelect.addEventListener("change", updateYears);
      yearSelect.addEventListener("change", updateChapters);
      chapterSelect.addEventListener("change", updateSections);
      sectionSelect.addEventListener("change", () => {
        clearSelectionGameData();
        updateStartButtonAvailability();
        updateBackLink();
      });
      scopeSelect.addEventListener("change", () => {
        clearSelectionGameData();
        updateStartButtonAvailability();
      });

      startBtn.addEventListener("click", loadSectionData);
      stopBtn.addEventListener("click", () => {
        if (!running) {
          stopGame(true);
          return;
        }

        endRound("Game stopped.");
      });

      function applySelectionFromQuery() {
        const params = new URLSearchParams(window.location.search);
        const school = params.get("school") || "";
        const year = params.get("year") || "";
        const chapter = params.get("chapter") || "";
        const section = params.get("section") || "";

        if (
          school &&
          Array.from(schoolSelect.options).some((o) => o.value === school)
        ) {
          schoolSelect.value = school;
          updateYears();
        }

        if (
          year &&
          Array.from(yearSelect.options).some((o) => o.value === year)
        ) {
          yearSelect.value = year;
          updateChapters();
        }

        if (
          chapter &&
          Array.from(chapterSelect.options).some((o) => o.value === chapter)
        ) {
          chapterSelect.value = chapter;
          updateSections();
        }

        if (
          section &&
          Array.from(sectionSelect.options).some((o) => o.value === section)
        ) {
          sectionSelect.value = section;
        }

        updateStartButtonAvailability();
        updateBackLink();
      }

      loadStructure().then(applySelectionFromQuery);
    </script>
  </body>
</html>