package api

import (
	"encoding/json"
	"net/http"
	"strings"
	"time"

	"nettopo-go/internal/scans"
)

type Handler struct {
	store scans.Store
}

func NewHandler(store scans.Store) *Handler {
	return &Handler{store: store}
}

func (h *Handler) Routes() http.Handler {
	mux := http.NewServeMux()
	mux.HandleFunc("GET /health", h.health)
	mux.HandleFunc("POST /api/scans", h.createScan)
	mux.HandleFunc("GET /api/scans/{id}", h.getScan)
	return withJSON(mux)
}

func (h *Handler) health(w http.ResponseWriter, _ *http.Request) {
	writeJSON(w, http.StatusOK, map[string]any{
		"status": "ok",
		"time":   time.Now().UTC(),
	})
}

func (h *Handler) createScan(w http.ResponseWriter, r *http.Request) {
	var req scans.CreateScanRequest
	if err := json.NewDecoder(r.Body).Decode(&req); err != nil {
		writeError(w, http.StatusBadRequest, "invalid json body")
		return
	}

	req.Name = strings.TrimSpace(req.Name)
	if req.Name == "" {
		req.Name = "manual-scan"
	}

	job, err := h.store.CreateScan(req)
	if err != nil {
		writeError(w, http.StatusBadRequest, err.Error())
		return
	}

	writeJSON(w, http.StatusCreated, map[string]any{
		"scan_id": job.ID,
		"status":  job.Status,
	})
}

func (h *Handler) getScan(w http.ResponseWriter, r *http.Request) {
	id := r.PathValue("id")
	if id == "" {
		writeError(w, http.StatusBadRequest, "scan id is required")
		return
	}

	job, ok := h.store.GetScan(id)
	if !ok {
		writeError(w, http.StatusNotFound, "scan not found")
		return
	}

	writeJSON(w, http.StatusOK, job)
}

func withJSON(next http.Handler) http.Handler {
	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		w.Header().Set("Content-Type", "application/json; charset=utf-8")
		next.ServeHTTP(w, r)
	})
}

func writeJSON(w http.ResponseWriter, status int, payload any) {
	w.WriteHeader(status)
	_ = json.NewEncoder(w).Encode(payload)
}

func writeError(w http.ResponseWriter, status int, message string) {
	writeJSON(w, status, map[string]string{"error": message})
}