package serverless

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

// RegisterRoutes registers all serverless routes on the given mux.
func (h *ServerlessHandlers) RegisterRoutes(mux *http.ServeMux) {
	// Function management
	mux.HandleFunc("/v1/functions", h.handleFunctions)
	mux.HandleFunc("/v1/functions/", h.handleFunctionByName)

	// Direct invoke endpoint
	mux.HandleFunc("/v1/invoke/", h.HandleInvoke)
}

// handleFunctions handles GET /v1/functions (list) and POST /v1/functions (deploy)
func (h *ServerlessHandlers) handleFunctions(w http.ResponseWriter, r *http.Request) {
	switch r.Method {
	case http.MethodGet:
		h.ListFunctions(w, r)
	case http.MethodPost:
		h.DeployFunction(w, r)
	default:
		http.Error(w, "Method not allowed", http.StatusMethodNotAllowed)
	}
}

// handleFunctionByName handles operations on a specific function
// Routes:
//   - GET    /v1/functions/{name}           - Get function info
//   - DELETE /v1/functions/{name}           - Delete function
//   - POST   /v1/functions/{name}/invoke    - Invoke function
//   - GET    /v1/functions/{name}/versions  - List versions
//   - GET    /v1/functions/{name}/logs      - Get logs
//   - WS     /v1/functions/{name}/ws        - WebSocket invoke
func (h *ServerlessHandlers) handleFunctionByName(w http.ResponseWriter, r *http.Request) {
	// Parse path: /v1/functions/{name}[/{action}]
	path := strings.TrimPrefix(r.URL.Path, "/v1/functions/")
	parts := strings.SplitN(path, "/", 2)

	if len(parts) == 0 || parts[0] == "" {
		http.Error(w, "Function name required", http.StatusBadRequest)
		return
	}

	name := parts[0]
	action := ""
	if len(parts) > 1 {
		action = parts[1]
	}

	// Parse version from name if present (e.g., "myfunction@2")
	version := 0
	if idx := strings.Index(name, "@"); idx > 0 {
		vStr := name[idx+1:]
		name = name[:idx]
		if v, err := strconv.Atoi(vStr); err == nil {
			version = v
		}
	}

	switch action {
	case "invoke":
		h.InvokeFunction(w, r, name, version)
	case "ws":
		h.HandleWebSocket(w, r, name, version)
	case "versions":
		h.ListVersions(w, r, name)
	case "logs":
		h.GetFunctionLogs(w, r, name)
	case "":
		switch r.Method {
		case http.MethodGet:
			h.GetFunctionInfo(w, r, name, version)
		case http.MethodDelete:
			h.DeleteFunction(w, r, name, version)
		default:
			http.Error(w, "Method not allowed", http.StatusMethodNotAllowed)
		}
	default:
		http.Error(w, "Unknown action", http.StatusNotFound)
	}
}