add basic theming support

README.md

@@ -57,6 +57,10 @@ typical workflow.
 After ingesting the data with `lieu ingest`, you can also use lieu to search the
 corpus in the terminal with `lieu search`.
 
+## Theming
+
+Tweak the `theme` values of the config, specified below.
+
 ## Config
 
 The config file is written in [TOML](https://toml.io/en/).
@@ -68,6 +72,12 @@ name = "Merveilles Webring"
 url = "https://webring.xxiivv.com"
 port = 10001
 
+[theme]
+# colors specified in hex (or valid css names) which determine the theme of the lieu instance
+foreground = "#ffffff"
+background = "#000000"
+links = "#ffffff"
+
 [data]
 # the source file should contain the crawl command's output 
 source = "data/crawled.txt"

html/head.html

@@ -12,6 +12,7 @@
         </style>
 
         <link href="/assets/style.css" rel="stylesheet">
+        <link href="/assets/theme.css" rel="stylesheet">
 
         <link rel="icon" href="/assets/favicon.ico">
         <link rel="icon" href="/assets/logo.svg" type="image/svg+xml">

server/server.go

@@ -227,7 +227,23 @@ func (h RequestHandler) renderView(res http.ResponseWriter, tmpl string, view *T
 	}
 }
 
+func WriteTheme(config types.Config) {
+	theme := config.Theme
+  // no theme is set, use the default
+  if theme.Foreground == "" {
+    return
+  }
+	colors := fmt.Sprintf(`:root {
+  --primary: %s;
+  --secondary: %s;
+  --link: %s;
+}\n`, theme.Foreground, theme.Background, theme.Links)
+	err := os.WriteFile("html/assets/theme.css", []byte(colors), 0644)
+	util.Check(err)
+}
+
 func Serve(config types.Config) {
+	WriteTheme(config)
 	db := database.InitDB(config.Data.Database)
 	handler := RequestHandler{config: config, db: db}
 

types/types.go

@@ -21,6 +21,11 @@ type Config struct {
 		URL         string `json:url`
 		Port        int    `json:port`
 	} `json:general`
+	Theme struct {
+		Foreground string `json:"foreground"`
+		Background string `json:"background"`
+		Links      string `json:"links"`
+	} `json:"theme"`
 	Data struct {
 		Source     string `json:source`
 		Database   string `json:database`

util/util.go

@@ -105,6 +105,12 @@ name = "Sweet Webring"
 url = "https://example.com/"
 port = 10001
 
+[theme]
+# colors specified in hex (or valid css names) which determine the theme of the lieu instance
+foreground = "#ffffff"
+background = "#000000"
+links = "#ffffff"
+
 [data]
 # the source file should contain the crawl command's output 
 source = "data/crawled.txt"