From 5c63bc44abbd7f0aa7ed439393f29d7cd67b5196 Mon Sep 17 00:00:00 2001
From: Patrik Oldsberg <poldsberg@gmail.com>
Date: Mon, 5 Apr 2021 21:16:20 +0200
Subject: [PATCH] config-schema: initial propper schema viewer

Signed-off-by: Patrik Oldsberg <poldsberg@gmail.com>
---
 .../components/SchemaViewer/SchemaViewer.tsx  | 261 +++++++++++++++++-
 1 file changed, 259 insertions(+), 2 deletions(-)

diff --git a/plugins/config-schema/src/components/SchemaViewer/SchemaViewer.tsx b/plugins/config-schema/src/components/SchemaViewer/SchemaViewer.tsx
index 3f4c11fc31..db29e5acbe 100644
--- a/plugins/config-schema/src/components/SchemaViewer/SchemaViewer.tsx
+++ b/plugins/config-schema/src/components/SchemaViewer/SchemaViewer.tsx
@@ -14,13 +14,270 @@
  * limitations under the License.
  */
 import React from 'react';
-import { CodeSnippet } from '@backstage/core';
 import { Schema } from 'jsonschema';
+import {
+  Box,
+  Chip,
+  Divider,
+  Paper,
+  Table,
+  TableBody,
+  TableCell,
+  TableRow,
+  Typography,
+} from '@material-ui/core';
+import { JsonValue } from '@backstage/config';
+
+interface SchemaViewProps {
+  path: string;
+  depth: number;
+  schema: Schema;
+}
+
+export interface MetadataViewRowProps {
+  label: string;
+  text?: string;
+  data?: JsonValue;
+}
+
+export function MetadataViewRow({ label, text, data }: MetadataViewRowProps) {
+  if (text === undefined && data === undefined) {
+    return null;
+  }
+  return (
+    <TableRow>
+      <TableCell variant="head" style={{ width: 160 }}>
+        <Typography variant="body1" noWrap>
+          {label}
+        </Typography>
+      </TableCell>
+      <TableCell>
+        <Typography variant="body1">
+          {data ? JSON.stringify(data) : text}
+        </Typography>
+      </TableCell>
+    </TableRow>
+  );
+}
+
+export function MetadataView({ schema }: { schema: Schema }) {
+  return (
+    <Paper variant="outlined" square style={{ width: '100%' }}>
+      <Table size="small">
+        <TableBody>
+          <MetadataViewRow label="Type" data={schema.type} />
+          <MetadataViewRow label="Allowed values" data={schema.enum} />
+          <MetadataViewRow label="Format" text={schema.format} />
+          <MetadataViewRow
+            label="Pattern"
+            text={schema.pattern && String(schema.pattern)}
+          />
+          <MetadataViewRow label="Minimum" data={schema.minimum} />
+          <MetadataViewRow label="Maximum" data={schema.maximum} />
+          <MetadataViewRow
+            label="Exclusive minimum"
+            data={schema.exclusiveMinimum}
+          />
+          <MetadataViewRow
+            label="Exclusive maximum"
+            data={schema.exclusiveMaximum}
+          />
+          <MetadataViewRow label="Multiple of" data={schema.multipleOf} />
+          <MetadataViewRow
+            label="Maximum number of items"
+            data={schema.maxItems}
+          />
+          <MetadataViewRow
+            label="Minimum number of items"
+            data={schema.minItems}
+          />
+          <MetadataViewRow
+            label="Maximum number of properties"
+            data={schema.maxProperties}
+          />
+          <MetadataViewRow
+            label="Minimum number of properties"
+            data={schema.minProperties}
+          />
+          <MetadataViewRow label="Maximum Length" data={schema.maxLength} />
+          <MetadataViewRow label="Minimum Length" data={schema.minLength} />
+          <MetadataViewRow
+            label="Items must be unique"
+            data={schema.uniqueItems}
+          />
+        </TableBody>
+      </Table>
+    </Paper>
+  );
+}
+
+export function ScalarView({ schema }: SchemaViewProps) {
+  return (
+    <>
+      {schema.description && (
+        <Box marginBottom={4}>
+          <Typography variant="body1">{schema.description}</Typography>
+        </Box>
+      )}
+      <MetadataView schema={schema} />
+    </>
+  );
+}
+
+function isRequired(name: string, required?: boolean | string[]) {
+  if (required === true) {
+    return true;
+  }
+  if (Array.isArray(required)) {
+    return required.includes(name);
+  }
+  return false;
+}
+
+function titleVariant(depth: number) {
+  if (depth <= 1) {
+    return 'h2';
+  } else if (depth === 2) {
+    return 'h3';
+  } else if (depth === 3) {
+    return 'h4';
+  } else if (depth === 4) {
+    return 'h5';
+  }
+  return 'h6';
+}
+
+export function VisibilityView({ schema }: { schema: Schema }) {
+  const { visibility } = schema as { visibility?: string };
+  if (visibility === 'frontend') {
+    return (
+      <Box
+        marginLeft={1}
+        children={<Chip label="frontend" color="primary" size="small" />}
+      />
+    );
+  } else if (visibility === 'secret') {
+    return (
+      <Box
+        marginLeft={1}
+        children={<Chip label="secret" color="secondary" size="small" />}
+      />
+    );
+  }
+  return null;
+}
+
+export function ArrayView({ path, depth, schema }: SchemaViewProps) {
+  const itemDepth = depth + 1;
+  const itemPath = path ? `${path}[]` : '[]';
+  const itemSchema = schema.items;
+
+  return (
+    <>
+      <Box marginBottom={4}>
+        {schema.description && (
+          <Box marginBottom={4}>
+            <Typography variant="body1">{schema.description}</Typography>
+          </Box>
+        )}
+        <MetadataView schema={schema} />
+      </Box>
+      <Typography variant="overline">Items</Typography>
+      <Box paddingBottom={2} display="flex" flexDirection="row">
+        <Divider orientation="vertical" flexItem />
+        <Box paddingLeft={2} flex={1}>
+          <Box marginBottom={2}>
+            <Typography variant={titleVariant(itemDepth)}>
+              {itemPath}
+            </Typography>
+          </Box>
+          {itemSchema && (
+            <SchemaView
+              path={itemPath}
+              depth={itemDepth}
+              schema={itemSchema as Schema}
+            />
+          )}
+        </Box>
+      </Box>
+    </>
+  );
+}
+
+export function ObjectView({ path, depth, schema }: SchemaViewProps) {
+  const properties = Object.entries(schema.properties ?? {});
+  return (
+    <>
+      {depth > 0 && (
+        <Box marginBottom={4}>
+          {schema.description && (
+            <Box marginBottom={4}>
+              <Typography variant="body1">{schema.description}</Typography>
+            </Box>
+          )}
+          <MetadataView schema={schema} />
+        </Box>
+      )}
+      {properties.length > 0 && (
+        <>
+          {depth > 0 && <Typography variant="overline">Properties</Typography>}
+          {properties.map(([name, propSchema], index) => {
+            const propDepth = depth + 1;
+            const propPath = path ? `${path}.${name}` : name;
+
+            return (
+              <Box
+                paddingBottom={index < properties.length - 1 ? 6 : 2}
+                display="flex"
+                flexDirection="row"
+              >
+                <Divider orientation="vertical" flexItem />
+                <Box paddingLeft={2} flex={1}>
+                  <Box display="flex" flexDirection="row" marginBottom={2}>
+                    <Typography variant={titleVariant(propDepth)}>
+                      {propPath}
+                    </Typography>
+                    {isRequired(name, schema.required) && (
+                      <Box marginLeft={1}>
+                        <Typography variant="subtitle2" color="textSecondary">
+                          required
+                        </Typography>
+                      </Box>
+                    )}
+                    <VisibilityView schema={propSchema} />
+                  </Box>
+                  <SchemaView
+                    path={propPath}
+                    depth={propDepth}
+                    schema={propSchema}
+                  />
+                </Box>
+              </Box>
+            );
+          })}
+        </>
+      )}
+    </>
+  );
+}
+
+export function SchemaView(props: SchemaViewProps) {
+  // TODO(Rugvip): allOf, anyOf, oneOf
+  switch (props.schema.type) {
+    case 'array':
+      return <ArrayView {...props} />;
+    case 'object':
+    case undefined:
+      return <ObjectView {...props} />;
+    default:
+      return <ScalarView {...props} />;
+  }
+}
 
 export interface SchemaViewerProps {
   schema: Schema;
 }
 
 export const SchemaViewer = ({ schema }: SchemaViewerProps) => {
-  return <CodeSnippet language="json" text={JSON.stringify(schema, null, 2)} />;
+  return <SchemaView schema={schema} path="" depth={0} />;
 };