Fix #161

src/app/components/calculator-list/calculator-list.component.html

 <div class="container" fxLayout="row wrap" fxLayoutAlign="space-evenly stretch">
 
+    <mat-card class="welcome-card" *ngIf="nbOpenCalculators === 0">
+
+        <mat-card-header>
+            <!-- <img mat-card-avatar src="https://s3.amazonaws.com/pix.iemoji.com/images/emoji/apple/ios-12/256/water-wave.png"> -->
+            <mat-card-title>{{ uitextWelcomeTitle }}</mat-card-title>
+            <mat-card-subtitle>{{ uitextWelcomeSubtitle }}</mat-card-subtitle>
+        </mat-card-header>
+
+        <mat-card-content [innerHTML]="uitextWelcomeContent">
+        </mat-card-content>
+
+        <img mat-card-image src="../../assets/images/logo_irstea_m.jpg">
+
+        <img mat-card-image src="../../assets/images/logo_afb_m.jpg">
+
+        <mat-card-actions>
+            <div class="container" fxLayout="column" fxLayoutAlign="left" fxLayoutGap="10px">
+                <button mat-raised-button color="accent" class="theme-calculator"></button>
+            </div>
+        </mat-card-actions>
+
+    </mat-card>
+
     <mat-card *ngFor="let theme of items" class="compute-nodes-theme">
 
         <mat-card-header>

src/app/components/calculator-list/calculator-list.component.scss

-mat-card.compute-nodes-theme {
+mat-card.compute-nodes-theme, mat-card.welcome-card {
     width: 300px;
     margin: 1em;
 
@@ -47,3 +47,10 @@ mat-card.compute-nodes-theme {
         }
     }
 }
+
+mat-card.welcome-card {
+
+    .mat-card-content {
+        line-height: 1.4em;
+    }
+}

src/app/components/calculator-list/calculator-list.component.ts

 import { Component, OnInit } from "@angular/core";
 import { Router } from "@angular/router";
 
-import { CalculatorType, EnumEx } from "jalhyd";
+import { CalculatorType, EnumEx, Session } from "jalhyd";
 
 import { FormulaireDefinition } from "../../formulaire/definition/form-definition";
 import { ServiceFactory } from "../../services/service-factory";
@@ -108,10 +108,26 @@ export class CalculatorListComponent implements OnInit {
         });
     }
 
+    public get nbOpenCalculators() {
+        return Session.getInstance().getNumberOfNubs();
+    }
+
     public get items() {
         return this._items;
     }
 
+    public get uitextWelcomeTitle() {
+        return "Cassiopée";
+    }
+
+    public get uitextWelcomeSubtitle() {
+        return ServiceFactory.instance.i18nService.localizeText("INFO_WELCOME_SUBTITLE");
+    }
+
+    public get uitextWelcomeContent() {
+        return ServiceFactory.instance.i18nService.localizeText("INFO_WELCOME_CONTENT");
+    }
+
     // interface Observer
 
     update(sender: any, data: any): void {

src/locale/messages.en.json

@@ -212,6 +212,7 @@
     "INFO_REQUIRES": "requires",
     "INFO_SECTIONPARAMETREE_TITRE": "Parametric section",
     "INFO_SECTIONPARAMETREE_TITRE_COURT": "Param. section",
+    "INFO_SETUP_LANGUAGE": "Language",
     "INFO_SETUP_NEWTON_MAX_ITER": "Newton iteration limit",
     "INFO_SETUP_PRECISION_AFFICHAGE": "Display accuracy",
     "INFO_SETUP_PRECISION_CALCUL": "Computation accuracy",
@@ -233,6 +234,8 @@
     "INFO_THEME_HYDRAULIQUE_EN_CHARGE_DESCRIPTION": "Modules for calculating head losses in pressure pipes",
     "INFO_THEME_LOIS_D_OUVRAGES_TITRE": "Hydraulic structures",
     "INFO_THEME_LOIS_D_OUVRAGES_DESCRIPTION": "Flow calculation for hydraulic devices (gates, weir, orifices)",
+    "INFO_WELCOME_SUBTITLE": "Hydraulic calculators",
+    "INFO_WELCOME_CONTENT": "<p>The Cassiopée software was developed by <a href=\"https://www.afbiodiversite.fr\">AFB</a> (French Agency for Biodiversity) and <a href=\"https://www.irstea.fr/en\">Irstea</a> (National Institute for Environmental and Agricultural Science and Research).</p><p>It includes tools for designing fish passes, and hydraulic calculation tools useful for environmental and agricultural engineering.</p><p>For more information, consult <a href=\"assets/docs-fr/mentions_legales\">legal notice</a> and <a href=\"assets/docs-fr\">documentation</a>.</p>",
     "WARNING_REMOUS_ARRET_CRITIQUE": "Calculation stopped: critical elevation reached at abscissa %x%",
     "WARNING_STRUCTUREKIVI_HP_TROP_ELEVE": "h/p must not be greater than 2.5. h/p is forced to 2.5",
     "WARNING_STRUCTUREKIVI_PELLE_TROP_FAIBLE": "Threshold height should be greater than 0.1 m. Beta coefficient is forced to 0"

src/locale/messages.fr.json

@@ -212,6 +212,7 @@
     "INFO_REQUIRES": "dépend de",
     "INFO_SECTIONPARAMETREE_TITRE": "Section paramétrée",
     "INFO_SECTIONPARAMETREE_TITRE_COURT": "Sec. param.",
+    "INFO_SETUP_LANGUAGE": "Langue",
     "INFO_SETUP_NEWTON_MAX_ITER": "Newton : nombre d'itérations maximum",
     "INFO_SETUP_PRECISION_AFFICHAGE": "Précision d'affichage",
     "INFO_SETUP_PRECISION_CALCUL": "Précision de calcul",
@@ -233,6 +234,8 @@
     "INFO_THEME_HYDRAULIQUE_EN_CHARGE_DESCRIPTION": "Modules de calcul de perte de charge dans les conduites sous pression",
     "INFO_THEME_LOIS_D_OUVRAGES_TITRE": "Lois d'ouvrages",
     "INFO_THEME_LOIS_D_OUVRAGES_DESCRIPTION": "Calculs basés sur les lois de débits d'ouvrages hydrauliques (Vannes, seuils, orifices)",
+    "INFO_WELCOME_SUBTITLE": "Modules de calcul hydrauliques",
+    "INFO_WELCOME_CONTENT": "<p>Le logiciel Cassiopée a été développé par l'<a href=\"https://www.afbiodiversite.fr\">AFB</a> (Agence Française pour la Biodiversité) et <a href=\"https://www.irstea.fr\">Irstea</a> (Institut national de Recherche en Sciences et Technologies pour l’Environnement et l’Agriculture).</p><p>Il regroupe des outils d'aide à la conception de passes à poissons et des outils de calcul hydraulique utiles pour l'ingénierie en environnement et agriculture.</p><p>Pour plus d'informations, consulter les <a href=\"assets/docs-fr/mentions_legales\">mentions légales</a> et la <a href=\"assets/docs-fr\">documentation</a>.</p>",
     "WARNING_REMOUS_ARRET_CRITIQUE": "Arrêt du calcul&nbsp;: hauteur critique atteinte à l'abscisse %x%",
     "WARNING_STRUCTUREKIVI_HP_TROP_ELEVE": "h/p ne doit pas être supérieur à 2,5. h/p est forcé à 2,5",
     "WARNING_STRUCTUREKIVI_PELLE_TROP_FAIBLE": "La pelle du seuil doit mesurer au moins 0,1 m. Le coefficient béta est forcé à 0"