package greet

import (
	"context"
	"encoding/json"
	"io"
	"net/http"

	"github.com/go-chi/chi/v5"
	"github.com/rs/zerolog/log"
)

type GreeterV2 interface {
	GreetV2(ctx context.Context, name string) string
}

type ApiV2Greet interface {
	RegisterRoutes(router chi.Router)
}

type apiV2GreetHandler struct {
	greeter GreeterV2
}

func NewApiV2GreetHandler(greeter GreeterV2) ApiV2Greet {
	return &apiV2GreetHandler{greeter: greeter}
}

func (h *apiV2GreetHandler) RegisterRoutes(router chi.Router) {
	log.Trace().Msg("Registering v2 greet routes")
	router.Post("/", h.handleGreetPost)
	log.Trace().Msg("v2 Greet routes registered")
}

type greetRequest struct {
	Name string `json:"name"`
}

type greetResponse struct {
	Message string `json:"message"`
}

func (h *apiV2GreetHandler) handleGreetPost(w http.ResponseWriter, r *http.Request) {
	// Read request body
	body, err := io.ReadAll(r.Body)
	if err != nil {
		http.Error(w, `{"error":"failed to read request body"}`, http.StatusBadRequest)
		return
	}

	// Parse JSON
	var req greetRequest
	if err := json.Unmarshal(body, &req); err != nil {
		http.Error(w, `{"error":"invalid JSON format"}`, http.StatusBadRequest)
		return
	}

	// Call service
	message := h.greeter.GreetV2(r.Context(), req.Name)

	// Write response
	h.writeJSONResponse(w, message)
}

func (h *apiV2GreetHandler) writeJSONResponse(w http.ResponseWriter, message string) {
	w.Header().Set("Content-Type", "application/json")
	json.NewEncoder(w).Encode(greetResponse{Message: message})
}