From 1c0e790618605cd4c0cdd08496b29e9f0a516b9e Mon Sep 17 00:00:00 2001
From: Julien Castets <castets.j@gmail.com>
Date: Tue, 25 Jul 2023 15:50:36 +0200
Subject: [PATCH] Allow to upload an arbitrary number of legal files

---
 mesads/app/forms.py                           | 12 +++-
 mesads/templates/webpack/formset_files.html   | 72 ++++++-------------
 mesads/templates/webpack/formset_files.ts     | 49 +++++++++++++
 mesads/templates/webpack/pages/ads.ts         |  3 +
 .../webpack/pages/ads_manager_decree.ts       |  3 +
 5 files changed, 87 insertions(+), 52 deletions(-)
 create mode 100644 mesads/templates/webpack/formset_files.ts

diff --git a/mesads/app/forms.py b/mesads/app/forms.py
index 6a0dce94..675ceaf3 100644
--- a/mesads/app/forms.py
+++ b/mesads/app/forms.py
@@ -140,7 +140,11 @@ def _should_delete_form(self, form):
 
 
 ADSLegalFileFormSet = inlineformset_factory(
-    ADS, ADSLegalFile, fields=("file",), can_delete=True, extra=25, max_num=25
+    ADS,
+    ADSLegalFile,
+    fields=("file",),
+    can_delete=True,
+    extra=0,
 )
 
 
@@ -164,7 +168,11 @@ class ADSSearchForm(forms.Form):
 
 
 ADSManagerDecreeFormSet = inlineformset_factory(
-    ADSManager, ADSManagerDecree, fields=("file",), can_delete=True, extra=5, max_num=5
+    ADSManager,
+    ADSManagerDecree,
+    fields=("file",),
+    can_delete=True,
+    extra=0,
 )
 
 
diff --git a/mesads/templates/webpack/formset_files.html b/mesads/templates/webpack/formset_files.html
index fc1e9f55..a4106d82 100644
--- a/mesads/templates/webpack/formset_files.html
+++ b/mesads/templates/webpack/formset_files.html
@@ -1,49 +1,13 @@
 {% comment %}Render a formset to upload one or several files.{% endcomment %}
-
-<script type="text/javascript">
-    // Workaround, because array.findLastIndex is only available for firefox>104
-    function findLastIndex(arr, func) {
-        for (i = arr.length; i > 0; --i) {
-            if (func(arr[i - 1])) {
-                return i - 1;
-            }
-        }
-        return -1;
-    }
-
-    function x_data() {
-        return {
-            numberOfFormsToDisplay: (() => {
-                const allForms = [...document.getElementsByClassName('formset-file')];
-                // list of booleans with one entry per form, true if the form is empty, false is the form is filled or has an error
-                const filled = allForms.map((e) => !!(e.querySelector('input[type="hidden"]') || e.querySelector('p.fr-error-text')));
-                // Index of the first filled form
-                const firstFilled = findLastIndex(filled, (e) => e === true);
-                // All the forms are empty, display one form
-                if (firstFilled < 0) {
-                    return 1;
-                }
-                return firstFilled + 1;
-            })(),
-        };
-    }
-</script>
-
-<div
-    class="fr-input-group"
-    x-data="x_data()"
->
+<div id="formset-files" class="fr-input-group" x-data="{extra: 0}">
     {{ formset.management_form }}
-
     {% for form in formset %}
         <div
             class="fr-download fr-download--card formset-file"
-            x-show="{{ forloop.counter0 }} < numberOfFormsToDisplay"
             x-data="{deleteFile: false}"
             x-bind:style="deleteFile ? {'background-color': 'rgb(253,222,222)'} : {'background-color': '#fff'}"
             x-transition
         >
-        {% comment %}Existing document {% endcomment %}
         {% if form.instance.file %}
             {{ form.id.as_hidden }}
             {{ form.file.as_hidden }}
@@ -90,15 +54,6 @@
                     Annuler la suppression
                 </label>
             </p>
-        {% comment %}New document {% endcomment %}
-        {% else %}
-            <div class="fr-upload-group">
-                <label class="fr-label" for="file-upload">
-                    <strong>Nouveau document</strong>
-                    <span class="fr-hint-text">Taille maximale : 10 Mo. Format préféré : pdf.</span>
-                </label>
-                <input class="fr-upload" type="file" id="{{ form.file.id_for_label }}" name="{{ form.file.html_name }}">
-            </div>
         {% endif %}
 
         {% comment %}Form errors {% endcomment %}
@@ -107,10 +62,27 @@
             {{ error }}
             </p>
         {% endfor %}
-
         </div>
     {% endfor %}
 
+    {% comment %}Extra forms to select new document{% endcomment %}
+    <template x-for="i in extra">
+        <div
+            class="fr-download fr-download--card formset-file"
+            x-data="{deleteFile: false}"
+            x-bind:style="deleteFile ? {'background-color': 'rgb(253,222,222)'} : {'background-color': '#fff'}"
+            x-transition
+        >
+            <div class="fr-upload-group">
+                <label class="fr-label" for="file-upload">
+                    <strong>Nouveau document</strong>
+                    <span class="fr-hint-text">Taille maximale : 10 Mo. Format préféré : pdf.</span>
+                </label>
+                <input class="fr-upload" type="file" id="{{ formset.empty_form.file.id_for_label }}" name="{{ formset.empty_form.file.html_name }}">
+            </div>
+        </div>
+    </template>
+
     {% for error in formset.non_form_errors %}
         <p class="fr-error-text">
             {{ error }}
@@ -120,10 +92,10 @@
     <button
         type="button"
         class="fr-btn fr-btn--sm fr-icon-add-circle-line fr-btn--icon-left fr-btn--secondary"
-        x-on:click="numberOfFormsToDisplay++"
-        x-show="numberOfFormsToDisplay < {{ formset.extra }}"
+        @click="extra++"
+        x-add-file-button
         {% if disabled %}disabled{% endif %}
     >
-        Ajouter un autre document
+        Ajouter un document
     </button>
 </div>
\ No newline at end of file
diff --git a/mesads/templates/webpack/formset_files.ts b/mesads/templates/webpack/formset_files.ts
new file mode 100644
index 00000000..fefbeabc
--- /dev/null
+++ b/mesads/templates/webpack/formset_files.ts
@@ -0,0 +1,49 @@
+import Alpine from "alpinejs";
+
+// This function must be called by the javascript page using formset_files.html
+// to setup the directive "add-file-button".
+export default function SetupFormsetFiles() {
+  Alpine.directive("add-file-button", (el, { expression }, { evaluate }) => {
+    el.addEventListener("click", () => {
+      const form = document.getElementById("formset-files");
+      if (!form) {
+        throw new Error("formset-files not found");
+      }
+
+      // Initial number of forms in the formset
+      const initialForms = Array.from(
+        form.querySelectorAll("input[type=hidden]")
+      ).find((form) => form.id.match(/INITIAL_FORMS/)) as HTMLInputElement;
+
+      const numInitialForms = parseInt(initialForms.value, 10);
+
+      // Retrieve the value of the "extra" x-data attribute
+      const extra = evaluate("extra") as number;
+
+      // For each file input (ie. for each new form), replace the string
+      // __prefix__ present in formset.empty_form.file.id_for_label and
+      // formset.empty_form.file.html_name by the form index. If the forms don't
+      // have a correct index, the files will be ignored by django.
+      el.parentElement
+        ?.querySelectorAll("input[type=file]")
+        .forEach((value) => {
+          const input = value as HTMLInputElement;
+
+          input.id = input.id.replace(
+            /__prefix__/g,
+            (extra + numInitialForms - 1).toString()
+          );
+          input.name = input.name.replace(
+            /__prefix__/,
+            (extra + numInitialForms - 1).toString()
+          );
+        });
+
+      const totalInput = Array.from(
+        form.querySelectorAll("input[type=hidden]")
+      ).find((form) => form.id.match(/TOTAL_FORMS/)) as HTMLInputElement;
+
+      totalInput.value = (parseInt(totalInput.value, 10) + 1).toString();
+    });
+  });
+}
diff --git a/mesads/templates/webpack/pages/ads.ts b/mesads/templates/webpack/pages/ads.ts
index d5da4781..2f049e5f 100644
--- a/mesads/templates/webpack/pages/ads.ts
+++ b/mesads/templates/webpack/pages/ads.ts
@@ -1,4 +1,7 @@
 import Alpine from "alpinejs";
+import SetupFormsetFiles from "../formset_files";
+
+SetupFormsetFiles();
 
 // array.findLastIndex is only available for firefox>104
 function findLastIndex(arr: any[], func: (e: any) => boolean) {
diff --git a/mesads/templates/webpack/pages/ads_manager_decree.ts b/mesads/templates/webpack/pages/ads_manager_decree.ts
index 67a4271b..771fe49b 100644
--- a/mesads/templates/webpack/pages/ads_manager_decree.ts
+++ b/mesads/templates/webpack/pages/ads_manager_decree.ts
@@ -1,3 +1,6 @@
 import Alpine from "alpinejs";
+import SetupFormsetFiles from "../formset_files";
+
+SetupFormsetFiles();
 
 Alpine.start();