Implement logging system

src/state/models/log.ts

@@ -0,0 +1,94 @@
+import {makeAutoObservable} from 'mobx'
+import {isObj, hasProp} from '../lib/type-guards'
+
+interface LogEntry {
+  id: string
+  type?: string
+  summary?: string
+  details?: string
+  ts?: number
+}
+
+let _lastTs: string
+let _lastId: string
+function genId(): string {
+  let candidate = String(Date.now())
+  if (_lastTs === candidate) {
+    const id = _lastId + 'x'
+    _lastId = id
+    return id
+  }
+  _lastTs = candidate
+  _lastId = candidate
+  return candidate
+}
+
+export class LogModel {
+  entries: LogEntry[] = []
+
+  constructor() {
+    makeAutoObservable(this, {serialize: false, hydrate: false})
+  }
+
+  serialize(): unknown {
+    return {
+      entries: this.entries.slice(-100),
+    }
+  }
+
+  hydrate(v: unknown) {
+    if (isObj(v)) {
+      if (hasProp(v, 'entries') && Array.isArray(v.entries)) {
+        this.entries = v.entries.filter(
+          e => isObj(e) && hasProp(e, 'id') && typeof e.id === 'string',
+        )
+      }
+    }
+  }
+
+  private add(entry: LogEntry) {
+    this.entries.push(entry)
+  }
+
+  debug(summary: string, details?: any) {
+    if (details && typeof details !== 'string') {
+      details = JSON.stringify(details, null, 2)
+    }
+    console.debug(summary, details || '')
+    this.add({
+      id: genId(),
+      type: 'debug',
+      summary,
+      details,
+      ts: Date.now(),
+    })
+  }
+
+  warn(summary: string, details?: any) {
+    if (details && typeof details !== 'string') {
+      details = JSON.stringify(details, null, 2)
+    }
+    console.warn(summary, details || '')
+    this.add({
+      id: genId(),
+      type: 'warn',
+      summary,
+      details,
+      ts: Date.now(),
+    })
+  }
+
+  error(summary: string, details?: any) {
+    if (details && typeof details !== 'string') {
+      details = JSON.stringify(details, null, 2)
+    }
+    console.error(summary, details || '')
+    this.add({
+      id: genId(),
+      type: 'error',
+      summary,
+      details,
+      ts: Date.now(),
+    })
+  }
+}