Atlas/internal/service/asset/url.go

package asset

import (
	"net/http"
	"strings"
)

const userFilesPathPrefix = "/api/v1/user/files/"

func PublicBaseURL(r *http.Request) string {
	scheme := "http"
	if r.TLS != nil {
		scheme = "https"
	}
	if proto := strings.TrimSpace(r.Header.Get("X-Forwarded-Proto")); proto != "" {
		scheme = strings.ToLower(proto)
	}
	host := r.Host
	if fwd := strings.TrimSpace(r.Header.Get("X-Forwarded-Host")); fwd != "" {
		host = strings.Split(fwd, ",")[0]
		host = strings.TrimSpace(host)
	}
	if host == "" {
		return ""
	}
	return scheme + "://" + host
}

func APIBaseURL(r *http.Request) string {
	base := PublicBaseURL(r)
	if base == "" {
		return ""
	}
	return strings.TrimRight(base, "/") + "/api/v1"
}

func ResolvePublicFileURLs(params map[string]any, publicBase string) {
	if publicBase == "" || len(params) == 0 {
		return
	}
	publicBase = strings.TrimRight(publicBase, "/")
	for key, value := range params {
		params[key] = resolvePublicFileValue(value, publicBase)
	}
}

func resolvePublicFileValue(value any, publicBase string) any {
	switch v := value.(type) {
	case string:
		return resolvePublicFileString(v, publicBase)
	case []any:
		out := make([]any, len(v))
		for i, item := range v {
			out[i] = resolvePublicFileValue(item, publicBase)
		}
		return out
	case []string:
		out := make([]string, len(v))
		for i, item := range v {
			out[i] = resolvePublicFileString(item, publicBase)
		}
		return out
	default:
		return value
	}
}

func resolvePublicFileString(raw, publicBase string) string {
	value := strings.TrimSpace(raw)
	if value == "" || !strings.HasPrefix(value, userFilesPathPrefix) {
		return raw
	}
	return publicBase + value
}