fix(themes): resolve built-in theme paths instead of hardcoding node_modules path

The previous method only worked locally inside the repo, but not once the package is published to npm.
Once published, built-in themes are flattened instead of nested.

package-lock.json

@@ -4155,6 +4155,21 @@
       "integrity": "sha1-Jsv+k10a7uq7Kbw/5a6wHpPUQiY=",
       "dev": true
     },
+    "resolve-pkg": {
+      "version": "1.0.0",
+      "resolved": "https://registry.npmjs.org/resolve-pkg/-/resolve-pkg-1.0.0.tgz",
+      "integrity": "sha1-4ZoV54rKLhJEYdySsuOUPvk0lNk=",
+      "requires": {
+        "resolve-from": "2.0.0"
+      },
+      "dependencies": {
+        "resolve-from": {
+          "version": "2.0.0",
+          "resolved": "https://registry.npmjs.org/resolve-from/-/resolve-from-2.0.0.tgz",
+          "integrity": "sha1-lICrIOlP+h2egKgEx+oUdhGWa1c="
+        }
+      }
+    },
     "resolve-url": {
       "version": "0.2.1",
       "resolved": "https://registry.npmjs.org/resolve-url/-/resolve-url-0.2.1.tgz",

package.json

@@ -54,6 +54,7 @@
     "micromatch": "^3.1.10",
     "moment": "^2.22.1",
     "readdir-enhanced": "^2.2.1",
+    "resolve-pkg": "^1.0.0",
     "through2": "^2.0.3",
     "thumbsup-downsize": "^2.1.0",
     "url-join": "^4.0.0",

src/website/website.js

@@ -1,9 +1,8 @@
 const path = require('path')
 const async = require('async')
+const resolvePkg = require('resolve-pkg')
 const Theme = require('./theme')
 
-const THUMBSUP_PACKAGES = path.join(__dirname, '..', '..', 'node_modules', '@thumbsup')
-
 exports.build = function (rootAlbum, opts, callback) {
   // create the base layer assets
   // such as shared JS libs, common handlebars helpers, CSS reset...
@@ -13,7 +12,7 @@ exports.build = function (rootAlbum, opts, callback) {
   })
 
   // then create the actual theme assets
-  const themeDir = opts.themePath || path.join(THUMBSUP_PACKAGES, `theme-${opts.theme}`)
+  const themeDir = opts.themePath || localThemePath(opts.theme)
   const theme = new Theme(themeDir, opts.output, {
     stylesheetName: 'theme.css',
     customStylesPath: opts.themeStyle
@@ -58,3 +57,11 @@ function createRenderingTasks (theme, album, gallery, breadcrumbs) {
   })
   return tasks
 }
+
+function localThemePath (themeName) {
+  const local = resolvePkg(`@thumbsup/theme-${themeName}`, {cwd: __dirname})
+  if (!local) {
+    throw new Error(`Could not find a built-in theme called ${themeName}`)
+  }
+  return local
+}