correction syntaxe appliquer promo

Reviewed-on: #9

my-library/src/pages/Orders.jsx

@@ -1,11 +1,17 @@
 import { useState } from 'react';
 import { createOrder } from '../api/orders';
+import { getBookById } from '../api/books';
 
 export default function Orders() {
   const [customerId, setCustomerId] = useState('');
   const [paymentMethod, setPaymentMethod] = useState('CREDIT_CARD');
   const [address, setAddress] = useState({ street: '', city: '', postalCode: '', country: '' });
   const [lines, setLines] = useState([{ bookId: '', quantity: 1 }]);
+  const [promoCode, setPromoCode] = useState('');
+  const [promoValid, setPromoValid] = useState(true);
+  const [estimate, setEstimate] = useState(null);
+  const [estimating, setEstimating] = useState(false);
+  const [estimateError, setEstimateError] = useState(null);
   const [message, setMessage] = useState(null);
   const [submitting, setSubmitting] = useState(false);
 
@@ -17,13 +23,66 @@ export default function Orders() {
   function handleLineChange(index, field, value) {
     setLines((prev) => prev.map((line, i) => (i === index ? { ...line, [field]: value } : line)));
   }
+
   function addLine() {
     setLines((prev) => [...prev, { bookId: '', quantity: 1 }]);
   }
+
   function removeLine(index) {
     setLines((prev) => prev.filter((_, i) => i !== index));
   }
 
+  function validatePromo(code) {
+    if (!code) return true;
+    return /^PROMO\d{1,2}$/.test(code);
+  }
+
+  function handlePromoChange(e) {
+    const code = e.target.value;
+    setPromoCode(code);
+    setPromoValid(validatePromo(code));
+  }
+
+  async function handleEstimate() {
+    setEstimating(true);
+    setEstimate(null);
+    setEstimateError(null);
+    try {
+      const ids = lines.map((l) => Number(l.bookId)).filter((n) => !isNaN(n) && n > 0);
+      if (ids.length === 0) {
+        setEstimateError('Aucun ISBN valide.');
+        return;
+      }
+      const unique = [...new Set(ids)];
+      const responses = await Promise.all(unique.map((id) => getBookById(id).then((r) => r.data)));
+      const priceMap = new Map();
+      unique.forEach((id, idx) => priceMap.set(id, responses[idx].prix ?? responses[idx].price ?? 0));
+
+      let total = 0;
+      for (const l of lines) {
+        const id = Number(l.bookId);
+        const qty = Number(l.quantity) || 0;
+        total += (priceMap.get(id) || 0) * qty;
+      }
+
+      let discounted = total;
+      if (promoCode) {
+        const m = promoCode.match(/^PROMO(\d{1,2})$/);
+        if (m) {
+          const pct = Math.max(0, Math.min(100, Number(m[1])));
+          discounted = total * (1 - pct / 100);
+        }
+      }
+
+      setEstimate({ total, discounted });
+    } catch (err) {
+      setEstimateError("Erreur lors de l'estimation.");
+      console.error(err);
+    } finally {
+      setEstimating(false);
+    }
+  }
+
   function handleSubmit(e) {
     e.preventDefault();
     setSubmitting(true);
@@ -37,10 +96,11 @@ export default function Orders() {
         bookId: Number(line.bookId),
         quantity: Number(line.quantity),
       })),
+      ...(promoCode ? { promoCode } : {}),
     };
 
     createOrder(payload)
-      .then((response) => setMessage('Commande créée'))
+      .then(() => setMessage('Commande créée avec succès !'))
       .catch((error) => {
         console.error(error);
         setMessage(error.response?.data?.message || 'Erreur lors de la commande.');
@@ -58,10 +118,10 @@ export default function Orders() {
 
         <h2>Livres</h2>
         {lines.map((line, index) => (
-          <div key={index}>
+          <div key={index} style={{ display: 'flex', gap: '0.5rem', marginBottom: '0.5rem' }}>
             <input type="number" placeholder="ISBN du livre" value={line.bookId}
               onChange={(e) => handleLineChange(index, 'bookId', e.target.value)} required />
-            <input type="number" placeholder="Quantité" value={line.quantity}
+            <input type="number" placeholder="Quantité" min="1" value={line.quantity}
               onChange={(e) => handleLineChange(index, 'quantity', e.target.value)} required />
             {lines.length > 1 && (
               <button type="button" onClick={() => removeLine(index)}>Retirer</button>
@@ -77,15 +137,35 @@ export default function Orders() {
         <input name="country" placeholder="Pays" value={address.country} onChange={handleAddressChange} required />
 
         <h2>Paiement</h2>
+        <label>Code promo (optionnel)
+          <input value={promoCode} onChange={handlePromoChange} placeholder="ex: PROMO10" />
+        </label>
+        {!promoValid && <p style={{ color: 'red' }}>Format invalide (ex: PROMO10)</p>}
+
         <select value={paymentMethod} onChange={(e) => setPaymentMethod(e.target.value)}>
           <option value="CREDIT_CARD">Carte bancaire</option>
         </select>
 
-        <button type="submit" disabled={submitting}>
+        <div>
+          <button type="button" onClick={handleEstimate} disabled={estimating}>
+            {estimating ? 'Estimation…' : 'Estimer le total'}
+          </button>
+          {estimateError && <p style={{ color: 'red' }}>{estimateError}</p>}
+          {estimate && (
+            <div>
+              <p>Total estimé : {estimate.total.toFixed(2)} €</p>
+              {estimate.total !== estimate.discounted && (
+                <p>Après promo : <strong>{estimate.discounted.toFixed(2)} €</strong></p>
+              )}
+            </div>
+          )}
+        </div>
+
+        <button type="submit" disabled={submitting || !promoValid}>
           {submitting ? 'Envoi…' : 'Valider la commande'}
         </button>
       </form>
-      {message && <p>{message}</p>}
+      {message && <p style={{ color: message.includes('succès') ? 'green' : 'red' }}>{message}</p>}
     </main>
   );
 }