From 7393b1293276866e11b990e1ac622a1033fffe9f Mon Sep 17 00:00:00 2001
From: kaveh <ka7eh@pm.me>
Date: Mon, 7 Nov 2022 16:18:26 +0100
Subject: [PATCH] Add API error message and links to code and docs in the
 header

---
 src/app.tsx                     | 97 ++++++++++++++++++++++++++++++++-
 src/components/Main/Content.tsx | 42 +-------------
 src/components/Main/Header.tsx  | 18 ++++++
 3 files changed, 115 insertions(+), 42 deletions(-)

diff --git a/src/app.tsx b/src/app.tsx
index 90823a8..d66a8ff 100755
--- a/src/app.tsx
+++ b/src/app.tsx
@@ -1,14 +1,91 @@
 import React, { StrictMode } from 'react';
+import axios from 'axios';
 import { createRoot } from 'react-dom/client';
 import { StyledEngineProvider, ThemeProvider } from '@mui/material/styles';
 import CssBaseline from '@mui/material/CssBaseline';
+import Box from '@mui/material/Box';
 
+import Icon from '@mui/material/Icon';
 import { StoreContext, initialState, reducers } from './store';
 import { theme } from './theme';
 import Content from './components/Main/Content';
 
+interface ReadyState {
+    model: 'loading' | 'ready' | 'error';
+    sites: 'loading' | 'ready' | 'error';
+    cases: 'loading' | 'ready' | 'error';
+    variables: 'loading' | 'ready' | 'error';
+}
+
 const App = (): JSX.Element => {
     const store = React.useReducer(reducers, initialState);
+    const dispatch = store[1];
+
+    const [readyState, updateReadyState] = React.useState<ReadyState>({
+        model: 'loading',
+        sites: 'loading',
+        cases: 'loading',
+        variables: 'loading'
+    });
+    const [hasAPIError, updateHasAPIError] = React.useState(false);
+
+    const handleReadyState = <R,>(url: string, category: keyof ReadyState, callback: (data: R) => void) => {
+        axios
+            .get<R>(url)
+            .then(({ data }) => {
+                callback(data);
+                updateReadyState((prevState) => ({
+                    ...prevState,
+                    [category]: 'ready'
+                }));
+            })
+            .catch((error) => {
+                console.error(error);
+                updateReadyState((prevState) => ({
+                    ...prevState,
+                    [category]: 'error'
+                }));
+                updateHasAPIError(true);
+            });
+    };
+
+    React.useEffect(() => {
+        dispatch({
+            type: 'updateLoadingState',
+            isLoading: true
+        });
+
+        handleReadyState<ModelInfo>(`${API_PATH}/cases/model-info`, 'model', (info) => {
+            dispatch({ type: 'updateModelInfo', info });
+        });
+
+        handleReadyState<GeoJSON.FeatureCollection<GeoJSON.Point, SiteProps>>(`${API_PATH}/sites`, 'sites', (sites) => {
+            dispatch({ type: 'updateSites', sites });
+        });
+
+        handleReadyState<CaseWithTaskInfo[]>(`${API_PATH}/cases`, 'cases', (cases) => {
+            dispatch({ type: 'updateCases', cases });
+        });
+
+        handleReadyState<CaseVariableConfig[]>(`${API_PATH}/cases/variables`, 'variables', (vars) => {
+            dispatch({ type: 'updateVariablesConfig', vars });
+        });
+    }, []);
+
+    React.useEffect(() => {
+        if (
+            hasAPIError ||
+            (readyState.model === 'ready' &&
+                readyState.sites === 'ready' &&
+                readyState.cases === 'ready' &&
+                readyState.variables === 'ready')
+        ) {
+            dispatch({
+                type: 'updateLoadingState',
+                isLoading: false
+            });
+        }
+    }, [readyState, hasAPIError]);
 
     return (
         <StrictMode>
@@ -16,7 +93,25 @@ const App = (): JSX.Element => {
             <StyledEngineProvider injectFirst>
                 <ThemeProvider theme={theme}>
                     <StoreContext.Provider value={store}>
-                        <Content />
+                        {hasAPIError ? (
+                            <Box
+                                sx={{
+                                    position: 'absolute',
+                                    display: 'flex',
+                                    justifyContent: 'center',
+                                    alignItems: 'center',
+                                    height: '100%',
+                                    width: '100%'
+                                }}
+                            >
+                                <Icon baseClassName="icons" fontSize="small" color="error">
+                                    error_outline
+                                </Icon>
+                                Cannot connect to API
+                            </Box>
+                        ) : (
+                            <Content />
+                        )}
                     </StoreContext.Provider>
                 </ThemeProvider>
             </StyledEngineProvider>
diff --git a/src/components/Main/Content.tsx b/src/components/Main/Content.tsx
index a46e79c..a737ae3 100644
--- a/src/components/Main/Content.tsx
+++ b/src/components/Main/Content.tsx
@@ -1,5 +1,4 @@
 import React from 'react';
-import axios from 'axios';
 import Box from '@mui/material/Box';
 import Divider from '@mui/material/Divider';
 
@@ -13,49 +12,10 @@ import Header from './Header';
 import Loading from './Loading';
 
 const Content = (): JSX.Element => {
-    const [state, dispatch] = React.useContext(StoreContext);
+    const [state] = React.useContext(StoreContext);
 
     const mapRef = React.useRef<maplibregl.Map>();
 
-    React.useEffect(() => {
-        axios.get<ModelInfo>(`${API_PATH}/cases/model-info`).then(({ data }) => {
-            dispatch({
-                type: 'updateModelInfo',
-                info: data
-            });
-        });
-
-        axios
-            .get<GeoJSON.FeatureCollection<GeoJSON.Point, SiteProps>>(`${API_PATH}/sites`)
-            .then(({ data }) => {
-                dispatch({ type: 'updateSites', sites: data });
-            })
-            .catch(console.error);
-
-        axios.get<CaseWithTaskInfo[]>(`${API_PATH}/cases`).then(({ data }) => {
-            dispatch({
-                type: 'updateCases',
-                cases: data
-            });
-        });
-
-        dispatch({
-            type: 'updateLoadingState',
-            isLoading: true
-        });
-        axios
-            .get<CaseVariableConfig[]>(`${API_PATH}/cases/variables`)
-            .then(({ data }) => {
-                dispatch({ type: 'updateVariablesConfig', vars: data });
-            })
-            .finally(() => {
-                dispatch({
-                    type: 'updateLoadingState',
-                    isLoading: false
-                });
-            });
-    }, []);
-
     return (
         <>
             <Header />
diff --git a/src/components/Main/Header.tsx b/src/components/Main/Header.tsx
index c524b1b..194dc53 100644
--- a/src/components/Main/Header.tsx
+++ b/src/components/Main/Header.tsx
@@ -49,6 +49,24 @@ const Header = () => {
                     >
                         <Icon baseClassName="icons">info</Icon>
                     </IconButton>
+                    <IconButton
+                        component={Link}
+                        color="inherit"
+                        href="https://noresmhub.github.io/noresm-land-sites-platform/"
+                        target="_blank"
+                        referrerPolicy="no-referrer"
+                    >
+                        <Icon baseClassName="icons">description</Icon>
+                    </IconButton>
+                    <IconButton
+                        component={Link}
+                        color="inherit"
+                        href="https://github.com/noresmhub/noresm-land-sites-platform/"
+                        target="_blank"
+                        referrerPolicy="no-referrer"
+                    >
+                        <Icon baseClassName="icons">code</Icon>
+                    </IconButton>
                 </Toolbar>
             </AppBar>
             <Dialog