Add the ability to use custom css

ui/form/settings.go

@@ -21,6 +21,7 @@ type SettingsForm struct {
 	Timezone          string
 	EntryDirection    string
 	KeyboardShortcuts bool
+	CustomCSS         string
 }
 
 // Merge updates the fields of the given user.
@@ -31,6 +32,7 @@ func (s *SettingsForm) Merge(user *model.User) *model.User {
 	user.Timezone = s.Timezone
 	user.EntryDirection = s.EntryDirection
 	user.KeyboardShortcuts = s.KeyboardShortcuts
+	user.Extra["custom_css"] = s.CustomCSS
 
 	if s.Password != "" {
 		user.Password = s.Password
@@ -74,5 +76,6 @@ func NewSettingsForm(r *http.Request) *SettingsForm {
 		Timezone:          r.FormValue("timezone"),
 		EntryDirection:    r.FormValue("entry_direction"),
 		KeyboardShortcuts: r.FormValue("keyboard_shortcuts") == "1",
+		CustomCSS:         r.FormValue("custom_css"),
 	}
 }

ui/settings_show.go

@@ -33,6 +33,7 @@ func (h *handler) showSettingsPage(w http.ResponseWriter, r *http.Request) {
 		Timezone:          user.Timezone,
 		EntryDirection:    user.EntryDirection,
 		KeyboardShortcuts: user.KeyboardShortcuts,
+		CustomCSS:         user.Extra["custom_css"],
 	}
 
 	timezones, err := h.store.Timezones()

ui/static_stylesheet.go

@@ -16,6 +16,24 @@ import (
 
 func (h *handler) showStylesheet(w http.ResponseWriter, r *http.Request) {
 	filename := request.RouteStringParam(r, "name")
+	if filename == "custom_css" {
+		user, err := h.store.UserByID(request.UserID(r))
+		if err != nil {
+			html.NotFound(w, r)
+			return
+		}
+		b := response.New(w, r)
+		if user == nil {
+			b.WithHeader("Content-Type", "text/css; charset=utf-8")
+			b.WithBody("")
+			b.Write()
+			return
+		}
+		b.WithHeader("Content-Type", "text/css; charset=utf-8")
+		b.WithBody(user.Extra["custom_css"])
+		b.Write()
+		return
+	}
 	etag, found := static.StylesheetsChecksums[filename]
 	if !found {
 		html.NotFound(w, r)