deal with simultaneous access to same order

orders/static/css/oders_helper_style.css

@@ -11,11 +11,33 @@
 
 /* - Common */
 
+.pill {
+    border-radius: 30px;
+    min-width: 200px;
+    min-height: 35px;
+    display: flex;
+    flex-direction: column;
+    justify-content: center;
+    align-items: center;
+    padding: 8px 15px 8px 15px;
+    margin: 0 10px 5px 0;
+}
+
+.disabled {
+    background-color: #c9cbce;
+}
+
+.disabled:hover {
+    background-color: #a1a2a3;
+}
 
 /* - Order selection screen */
+#new_order_area {
+    margin-bottom: 40px;
+}
+
 #new_order_form {
     margin-top: 20px;
-    margin-bottom: 30px;
 }
 
 #existing_orders {
@@ -25,24 +47,25 @@
     flex-wrap: wrap;
     width: 80%;
     margin: 0 auto;
-    padding-top: 20px;
+    padding-top: 15px;
 }
 
-.order_pill {
-    border-radius: 30px;
-    min-width: 200px;
-    min-height: 40px;
-    display: flex;
-    flex-direction: column;
-    justify-content: center;
-    align-items: center;
-    padding: 8px;
-    margin: 0 10px 5px 0;
+.order_last_update {
+    font-weight: bold;
+}
+
+.order_modified_msg {
+    font-size: 2rem;
+    color: #e62720;
 }
 
 /* - Main screen */
 
-/* -- Top right action button(s) */
+/* -- Top action button(s) */
+#back_to_order_selection {
+    position: absolute;
+}
+
 #actions_buttons_area {
     position: absolute;
     top: 0;
@@ -108,15 +131,6 @@
 
 .supplier_pill {
     background-color: #e7e9ed;
-    border-radius: 50px;
-    width: 200px;
-    min-height: 35px;
-    display: flex;
-    flex-direction: column;
-    justify-content: center;
-    align-items: center;
-    padding: 8px;
-    margin-right: 10px;
 }
 
 .remove_supplier_icon {

orders/static/js/orders_helper.js

@@ -7,12 +7,19 @@ var suppliers_list = [],
     sync = null,
     order_doc = {
         _id: null,
+        last_update : {
+            timestamp: null,
+            fingerprint: null,
+        },
         products: [],
         selected_suppliers: [],
         selected_rows: []
-    };
+    },
+    fingerprint = null;
 
 
+/* - UTILS */
+
 /**
  * Reset data that changes between screens
  */
@@ -22,11 +29,40 @@ function reset_data() {
     selected_rows = [],
     order_doc = {
         _id: null,
+        last_update : {
+            timestamp: null,
+            fingerprint: null,
+        },
         products: [],
         selected_suppliers: []
     };
 }
 
+/**
+ * Difference between two dates
+ * @param {Date} date1 
+ * @param {Date} date2 
+ * @returns difference object
+ */
+function dates_diff(date1, date2) {
+    var diff = {}
+    var tmp = date2 - date1;
+ 
+    tmp = Math.floor(tmp/1000);
+    diff.sec = tmp % 60;
+ 
+    tmp = Math.floor((tmp-diff.sec)/60);
+    diff.min = tmp % 60;
+ 
+    tmp = Math.floor((tmp-diff.min)/60);
+    diff.hours = tmp % 24;
+     
+    tmp = Math.floor((tmp-diff.hours)/24);
+    diff.days = tmp;
+     
+    return diff;
+}
+
 /* - SUPPLIERS */
 
 /**
@@ -494,13 +530,6 @@ function display_products() {
                 if (cell.hasClass("supplier_input_cell")) {
                     if (cell.text() == "X") {
                         cell.addClass('product_not_from_supplier');
-                    } else {
-                        // TODO: supplier shortage cell coloring, when supplier shortage usecase is defined
-
-                        // let val = parseFloat(cell.find('.product_qty_input').val());
-                        // if (!isNaN(val) && val < 0) {
-                        //     cell.addClass( 'product_supplier_shortage' );
-                        // }
                     }
                 }
             }
@@ -554,7 +583,7 @@ function display_products() {
     });
 
     // Select row(s) on checkbox change
-    $('#products_table').on('click', 'thead th #select_all_products_cb', function () {
+    $(products_table.table().header()).on('click', 'th #select_all_products_cb', function () {
         if (this.checked) {
             selected_rows = [];
             products_table.rows().every(function() {
@@ -619,6 +648,7 @@ function update_main_screen() {
     $('#products_table').off('click', 'tbody td .select_product_cb');
     $(".remove_supplier_icon").off();
 
+    $(".order_name_container").text(order_doc._id);
     display_suppliers();
     display_products();
 
@@ -646,37 +676,23 @@ function update_order_selection_screen() {
     $(".order_pill").off();
 
     let existing_orders_container = $("#existing_orders");
-
     existing_orders_container.empty();
 
     dbc.allDocs({
         include_docs: true
     }).then(function (result) {
+        if (result.rows.length === 0) {
+            existing_orders_container.append(`<i>Aucune commande en cours...</i>`);
+        } else {
             for (let row of result.rows) {
                 let template = $("#templates #order_pill_template");
-
                 template.find(".pill_order_name").text(row.id);
     
                 existing_orders_container.append(template.html());
             }
 
-        $(".order_pill").on("click", function() {
-            let order_name_container = $(this).find('.pill_order_name');
-            let doc_id = $(order_name_container).text();
-
-            dbc.get(doc_id).then((doc) => {
-                order_doc = doc;
-                products = order_doc.products;
-                selected_suppliers = order_doc.selected_suppliers;
-
-                update_main_screen();
-                switch_screen();
-            })
-                .catch(function (err) {
-                    alert('Erreur lors de la récupération de la commande. Si l\'erreur persiste, contactez un administrateur svp.');
-                    console.log(err);
-                });
-        });
+            $(".order_pill").on("click", order_pill_on_click);
+        }
     })
         .catch(function (err) {
             alert('Erreur lors de la synchronisation des commandes. Vous pouvez créer une nouvelle commande.');
@@ -718,6 +734,65 @@ function switch_screen(direction = 'main_screen') {
 
 /* - ORDER */
 
+function goto_main_screen(doc) {
+    order_doc = doc;
+    products = order_doc.products;
+    selected_suppliers = order_doc.selected_suppliers;
+
+    update_order()
+    update_main_screen();
+    switch_screen();
+}
+
+function back() {
+    reset_data();
+    update_order_selection_screen();
+    switch_screen('order_selection');
+}
+	
+/**
+ * Event fct: on click on an order button 
+ */
+function order_pill_on_click() {
+    let order_name_container = $(this).find('.pill_order_name');
+    let doc_id = $(order_name_container).text();
+
+    dbc.get(doc_id).then((doc) => {
+        if (doc.last_update.fingerprint !== fingerprint) {
+            time_diff = dates_diff(new Date(doc.last_update.timestamp), new Date())
+            diff_str = ``
+
+            if (time_diff.days !== 0) {
+                diff_str += `${time_diff.days} jour(s), `
+            }
+            if (time_diff.hours !== 0) {
+                diff_str += `${time_diff.hours} heure(s), `
+            }
+            if (time_diff.min !== 0) {
+                diff_str += `${time_diff.min} min, `
+            }
+            diff_str += `${time_diff.sec}s`
+
+            let modal_order_access = $('#templates #modal_order_access');
+            modal_order_access.find(".order_last_update").text(diff_str);
+
+            openModal(
+                modal_order_access.html(),
+                () => {
+                    goto_main_screen(doc)
+                },
+                'Valider'
+            );
+        } else {
+            goto_main_screen(doc)
+        }
+    })
+    .catch(function (err) {
+        alert('Erreur lors de la récupération de la commande. Si l\'erreur persiste, contactez un administrateur svp.');
+        console.log(err);
+    });
+}
+
 /**
  * Create an order in couchdb if the name doesn't exist
  */
@@ -739,12 +814,18 @@ function create_order() {
 }
 
 /**
- * Update an existing order in couchdb
+ * Update order data of an existing order in couchdb
  */
 function update_order() {
     order_doc.products = products;
     order_doc.selected_suppliers = selected_suppliers;
 
+    // Save that current user last updated the order
+    order_doc.last_update = {
+        timestamp: Date.now(),
+        fingerprint: fingerprint,
+    };
+
     dbc.put(order_doc, function callback(err, result) {
         if (!err && result !== undefined) {
             order_doc._rev = result.rev;
@@ -757,6 +838,7 @@ function update_order() {
 
 
 $(document).ready(function() {
+    fingerprint = new Fingerprint({canvas: true}).get();
     $.ajaxSetup({ headers: { "X-CSRFToken": getCookie('csrftoken') } });
 
     openModal();
@@ -770,10 +852,27 @@ $(document).ready(function() {
     });
 
     sync.on('change', function (info) {
-        console.log(info);
-        // TODO get current order new data (ou prévenir de changements ? -> pas changer les infos brutalement sans prévenir)
-        // TODO alert if current doc was deleted
+        if (info.direction === "pull") {
+            for (const doc of info.change.docs) {
+                // If current order was modified somewhere else
+                if (order_doc._id === doc._id && order_doc._rev !== doc._rev) {
+                    $.notify(
+                        "Un autre navigateur est en train de modifier cette commande !",
+                        {
+                            globalPosition:"top right",
+                            className: "error"
+                        }
+                    );
+                    back();
+                    break;
+                }
+            }
+        }
     }).on('error', function (err) {
+        if (err.status === 409) {
+            alert("Une erreur de synchronisation s'est produite, la commande a sûrement été modifiée sur un autre navigateur. Vous allez être redirigé.e.");
+            back();
+        } 
         console.log('erreur sync');
         console.log(err);
     });
@@ -789,9 +888,7 @@ $(document).ready(function() {
     });
 
     $('#back_to_order_selection').on('click', function() {
-        reset_data();
-        update_order_selection_screen();
-        switch_screen('order_selection');
+        back();
     });
 
     // Order selection screen

templates/orders/helper.html

@@ -16,14 +16,18 @@
 {% block content %}
 <div class="page_body">
     <div id="select_order_content" class="page_content txtcenter">
+        <div id="new_order_area">
             <h2>Créer une nouvelle commande</h2>
             <form id="new_order_form">
                 <input type="text" id="new_order_name" placeholder="Nom de la commande...">
                 <button type="submit" class="btn btn--primary">Valider</button>
             </form>
+        </div>
+        <div id="existing_orders_area">
             <h2>Ou, continuer une commande existante</h2>
             <div id="existing_orders"></div>
         </div>
+    </div>
 
     <div id="main_content" class="page_content" style="display:none;">
         <div id="back_to_order_selection">
@@ -35,6 +39,7 @@
     
         <div class="header txtcenter">
             <h1>Aide à la commande</h1>
+            <i>Commande : <span class="order_name_container"></span></i>
         </div>
     
         <div class="txtcenter" id="supplier_form_container">
@@ -55,7 +60,7 @@
 
     <div id="templates" style="display:none;">
         <div id="supplier_pill_template">
-            <div class="supplier_pill">
+            <div class="pill supplier_pill">
                 <div class="supplier_name_container">
                     <span class="pill_supplier_name"></span>
                     <i class="fas fa-times remove_supplier_icon"></i>
@@ -69,6 +74,20 @@
             </div>
         </div>
 
+        <div id="modal_order_access">
+            <h3>Attention !</h3>
+            <br/>
+            <p class="order_modified_msg"> 
+                Un autre navigateur a modifié cette commande il y a <span class="order_last_update"></span>.
+            </p><br/>
+            <p>
+                Si quelqu'un d'autre que vous est à l'origine de la modification et que celle-ci est récente,
+                nous conseillons fortement de ne pas accéder à la commande afin d'éviter les conflits.
+            </p><br/>
+            <p>Voulez-vous quand même y accéder ?</p>
+            <hr/>
+        </div>
+    
         <div id="modal_remove_supplier">
             <h3>Attention !</h3>
             <p>