Autocolors

WIP on a new feature: trying to guess current Peertube theme's colors,
and apply them to ConverseJS.

shared/lib/autocolors.ts

@@ -0,0 +1,59 @@
+import type { ChatType } from './types'
+
+type AutoColorValue = string
+
+interface AutoColors {
+  mainForeground: AutoColorValue
+  mainBackground: AutoColorValue
+  greyForeground: AutoColorValue
+  greyBackground: AutoColorValue
+  menuForeground: AutoColorValue
+  menuBackground: AutoColorValue
+  inputForeground: AutoColorValue
+  inputBackground: AutoColorValue
+  buttonForeground: AutoColorValue
+  buttonBackground: AutoColorValue
+  link: AutoColorValue
+  linkHover: AutoColorValue
+}
+
+/**
+ * @param chatType value of the settings 'chat-type'
+ * @param theme value of the settings 'converse-theme'
+ * @returns true if the theme can use autocolors
+ */
+function isAutoColorsAvailable (chatType: ChatType, theme: string): boolean {
+  if (chatType !== 'builtin-prosody' && chatType !== 'builtin-converse') {
+    return false
+  }
+  return theme === 'peertube' // currently the only theme that can handle autocolors.
+}
+
+/**
+ * @param autocolors
+ * @returns true if ok. Else a string array with invalid values.
+ */
+function areAutoColorsValid (autocolors: AutoColors): true | string[] {
+  const errors: string[] = []
+  for (const k in autocolors) {
+    const color = autocolors[k as keyof AutoColors]
+    // FIXME: there are missing cases. For now there are only basic values formats.
+    if (
+      !/^rgb\(\d{1,3},\s*\d{1,3},\s*\d{1,3}\)$/.test(color) &&
+      !/^rgba\(\d{1,3},\s*\d{1,3},\s*\d{1,3},\s*(1|0|0?.\d+)\)$/.test(color) &&
+      !/^#[0-9a-fA-F]{3,6}$/.test(color)
+    ) {
+      errors.push(color)
+    }
+  }
+  if (errors.length) {
+    return errors
+  }
+  return true
+}
+
+export {
+  AutoColors,
+  isAutoColorsAvailable,
+  areAutoColorsValid
+}