package cas

import (
	"io"
	"net/http"
	"strings"
)

type Fetcher interface {
	FetchTo(hash string, w http.ResponseWriter) bool
}

type HTTP struct {
	S       *Store
	Fetcher Fetcher // optional, for federation
}

// Public: GET /c/<hash>
func (h *HTTP) Serve(w http.ResponseWriter, r *http.Request) {
	hash := strings.TrimPrefix(r.URL.Path, "/c/")
	if hash == "" {
		w.WriteHeader(400)
		return
	}
	if h.S.Has(hash) {
		w.Header().Set("Cache-Control", "public, max-age=31536000, immutable")
		_ = h.S.Get(hash, w)
		return
	}
	if h.Fetcher != nil && h.Fetcher.FetchTo(hash, w) {
		return
	}
	w.WriteHeader(404)
}

// Mesh: GET /_mesh/cas/<hash> → raw bytes
func (h *HTTP) MeshGet(w http.ResponseWriter, r *http.Request) {
	hash := strings.TrimPrefix(r.URL.Path, "/_mesh/cas/")
	if hash == "" {
		w.WriteHeader(400)
		return
	}
	if !h.S.Has(hash) {
		w.WriteHeader(404)
		return
	}
	_ = h.S.Get(hash, w)
}

// Mesh: POST /_mesh/cas/put → returns hash as text
func (h *HTTP) MeshPut(w http.ResponseWriter, r *http.Request) {
	hash, err := h.S.PutStream(r.Body)
	if err != nil {
		w.WriteHeader(500)
		return
	}
	io.WriteString(w, hash)
}