{% extends 'mobile/mobile_base.html' %}
{% load static %}
{% load i18n %}

{% block title %}{% translate "Scanner QR" %}{% endblock title %}

{% block upleft %}
<a href="javascript:history.back()" class="nav-link" style="color: white;">
    <i class="bi bi-arrow-left fs-3"></i>
</a>
{% endblock upleft %}

{% block extra_head %}
<style>
    #scanner-container {
        position: relative;
        width: 100%;
        max-width: 400px;
        margin: 0 auto;
    }
    #video {
        width: 100%;
        border-radius: 1rem;
        background: #000;
        display: block;
    }
    #canvas { display: none; }
    #scan-overlay {
        position: absolute;
        top: 50%;
        left: 50%;
        transform: translate(-50%, -50%);
        width: 60%;
        aspect-ratio: 1;
        border: 3px solid rgba(255,255,255,0.85);
        border-radius: 0.75rem;
        box-shadow: 0 0 0 9999px rgba(0,0,0,0.35);
        pointer-events: none;
    }
    #scan-line {
        position: absolute;
        left: 5%;
        right: 5%;
        height: 2px;
        background: linear-gradient(to right, transparent, #2f3e8b, transparent);
        animation: scanline 2s linear infinite;
    }
    @keyframes scanline {
        0%   { top: 8%; }
        100% { top: 92%; }
    }
    #status-bar {
        text-align: center;
        padding: 0.75rem 0 0.5rem;
        font-size: 0.9rem;
        color: #6c757d;
        min-height: 2.5rem;
    }
    #result-card {
        display: none;
        border-radius: 0.75rem;
        border: 1px solid #dee2e6;
        padding: 1rem;
        margin-top: 1rem;
        background: #fff;
        box-shadow: 0 2px 8px rgba(47,62,139,0.08);
        text-align: center;
    }
    #error-card {
        display: none;
        border-radius: 0.75rem;
        border: 1px solid #f5c2c7;
        padding: 1rem;
        margin-top: 1rem;
        background: #fff3f4;
        text-align: center;
        color: #842029;
    }
    #start-btn, #restart-btn {
        display: block;
        width: 100%;
        max-width: 400px;
        margin: 1rem auto 0;
    }
</style>
{% endblock extra_head %}

{% block content %}

<div class="text-center mb-3">
    <p class="text-muted" style="font-size:0.9rem;">
        {% translate "Pointez la caméra vers un QR code StreetUp pour être redirigé automatiquement." %}
    </p>
</div>

<div id="scanner-container">
    <video id="video" autoplay playsinline muted></video>
    <canvas id="canvas"></canvas>
    <div id="scan-overlay"><div id="scan-line"></div></div>
</div>

<div id="status-bar">{% translate "Initialisation de la caméra…" %}</div>

<div id="result-card">
    <i class="bi bi-check-circle-fill text-success fs-3 d-block mb-2"></i>
    <div id="result-text" class="fw-semibold mb-3"></div>
    <a id="result-link" class="btn btn-primary w-100">{% translate "Ouvrir" %}</a>
</div>

<div id="error-card">
    <i class="bi bi-exclamation-triangle-fill fs-3 d-block mb-2"></i>
    <div id="error-text" class="mb-3"></div>
    <button id="restart-btn-err" class="btn btn-outline-secondary btn-sm">{% translate "Réessayer" %}</button>
</div>

<button id="start-btn" class="btn btn-outline-secondary" style="display:none;">
    <i class="bi bi-camera me-1"></i>{% translate "Démarrer la caméra" %}
</button>

<!-- jsQR via CDN -->
<script src="https://cdn.jsdelivr.net/npm/jsqr@1.4.0/dist/jsQR.min.js"></script>
<script>
(function () {
    const video    = document.getElementById('video');
    const canvas   = document.getElementById('canvas');
    const ctx      = canvas.getContext('2d');
    const statusEl = document.getElementById('status-bar');
    const resultCard = document.getElementById('result-card');
    const resultText = document.getElementById('result-text');
    const resultLink = document.getElementById('result-link');
    const errorCard  = document.getElementById('error-card');
    const errorText  = document.getElementById('error-text');
    const startBtn   = document.getElementById('start-btn');
    const restartErrBtn = document.getElementById('restart-btn-err');

    const RESOLVE_URL = "{% url 'mobile:qr_resolve' %}";

    let scanning = false;
    let rafId = null;

    function setStatus(msg) { statusEl.textContent = msg; }

    async function startCamera() {
        startBtn.style.display = 'none';
        resultCard.style.display = 'none';
        errorCard.style.display = 'none';
        setStatus("{% translate 'Initialisation de la caméra…' %}");
        try {
            const stream = await navigator.mediaDevices.getUserMedia({
                video: { facingMode: { ideal: 'environment' }, width: { ideal: 1280 }, height: { ideal: 720 } }
            });
            video.srcObject = stream;
            video.onloadedmetadata = () => {
                video.play();
                scanning = true;
                setStatus("{% translate 'Pointez vers un QR code…' %}");
                tick();
            };
        } catch (err) {
            setStatus('');
            startBtn.style.display = 'block';
            console.error('Camera error:', err);
        }
    }

    function tick() {
        if (!scanning) return;
        if (video.readyState === video.HAVE_ENOUGH_DATA) {
            canvas.width  = video.videoWidth;
            canvas.height = video.videoHeight;
            ctx.drawImage(video, 0, 0);
            const imageData = ctx.getImageData(0, 0, canvas.width, canvas.height);
            const code = jsQR(imageData.data, imageData.width, imageData.height, {
                inversionAttempts: 'dontInvert'
            });
            if (code) {
                scanning = false;
                cancelAnimationFrame(rafId);
                handleCode(code.data);
                return;
            }
        }
        rafId = requestAnimationFrame(tick);
    }

    function stopCamera() {
        scanning = false;
        if (video.srcObject) {
            video.srcObject.getTracks().forEach(t => t.stop());
            video.srcObject = null;
        }
    }

    async function handleCode(data) {
        setStatus("{% translate 'QR Code détecté, résolution…' %}");
        try {
            const resp = await fetch(RESOLVE_URL + '?code=' + encodeURIComponent(data), {
                headers: { 'X-Requested-With': 'XMLHttpRequest' }
            });
            const json = await resp.json();
            if (json.url) {
                stopCamera();
                resultText.textContent = json.label || data;
                resultLink.href = json.url;
                resultCard.style.display = 'block';
                setStatus('');
                // Redirection automatique après 1.2s
                setTimeout(() => { window.location.href = json.url; }, 1200);
            } else {
                showError(json.error || "{% translate 'QR Code non reconnu.' %}");
            }
        } catch (e) {
            showError("{% translate 'Erreur lors de la résolution.' %}");
        }
    }

    function showError(msg) {
        errorText.textContent = msg;
        errorCard.style.display = 'block';
        setStatus('');
        // Reprendre le scan après 2.5s
        setTimeout(() => {
            errorCard.style.display = 'none';
            scanning = true;
            setStatus("{% translate 'Pointez vers un QR code…' %}");
            tick();
        }, 2500);
    }

    restartErrBtn.addEventListener('click', () => {
        errorCard.style.display = 'none';
        scanning = true;
        setStatus("{% translate 'Pointez vers un QR code…' %}");
        tick();
    });

    startBtn.addEventListener('click', startCamera);

    // Démarrage automatique
    startCamera();
})();
</script>
{% endblock content %}