package sourcing

import (
	"encoding/json"
	"errors"
	"net/http"

	"github.com/go-chi/chi/v5"
	"github.com/google/uuid"

	"github.com/missionworkforce/missionmatch/internal/platform/security"
	"github.com/missionworkforce/missionmatch/internal/platform/tenant"
)

// Handler serves the external sourcing read API and the delete path.
type Handler struct{ svc *Service }

func NewHandler(svc *Service) *Handler { return &Handler{svc: svc} }

// Routes mounts the sourcing endpoints under the tenant scoped /api group. The contact fields and the
// compliance log require sourcing.read, and erasure of a sourced candidate requires the destructive
// privacy.erase capability, so these privacy sensitive paths are held to a privacy capable role.
func (h *Handler) Routes(r chi.Router) {
	r.With(security.RequireCapability(security.CapSourcingRead)).Get("/sourcing/candidates", h.list)
	r.With(security.RequireCapability(security.CapSourcingRead)).Get("/sourcing/log", h.log)
	r.With(security.RequireCapability(security.CapPrivacyErase)).Delete("/sourcing/candidates/{id}", h.del)
}

func (h *Handler) list(w http.ResponseWriter, r *http.Request) {
	items, err := h.svc.ListExternal(r.Context())
	writeResult(w, items, err)
}

func (h *Handler) log(w http.ResponseWriter, r *http.Request) {
	items, err := h.svc.Log(r.Context())
	writeResult(w, items, err)
}

func (h *Handler) del(w http.ResponseWriter, r *http.Request) {
	id, err := uuid.Parse(chi.URLParam(r, "id"))
	if err != nil {
		writeJSON(w, http.StatusBadRequest, map[string]string{"error": "invalid id"})
		return
	}
	err = h.svc.Delete(r.Context(), id)
	switch {
	case err == nil:
		writeJSON(w, http.StatusOK, map[string]string{"status": "deleted"})
	case errors.Is(err, ErrNotFound):
		writeJSON(w, http.StatusNotFound, map[string]string{"error": "not found"})
	case errors.Is(err, tenant.ErrNoTenant):
		writeJSON(w, http.StatusForbidden, map[string]string{"error": "no validated tenant"})
	case errors.Is(err, ErrNoDatabase):
		writeJSON(w, http.StatusServiceUnavailable, map[string]string{"error": "database not configured"})
	default:
		writeJSON(w, http.StatusInternalServerError, map[string]string{"error": "internal error"})
	}
}

func writeResult(w http.ResponseWriter, items any, err error) {
	if err != nil {
		switch {
		case errors.Is(err, tenant.ErrNoTenant):
			writeJSON(w, http.StatusForbidden, map[string]string{"error": "no validated tenant"})
		case errors.Is(err, ErrNoDatabase):
			writeJSON(w, http.StatusServiceUnavailable, map[string]string{"error": "database not configured"})
		default:
			writeJSON(w, http.StatusInternalServerError, map[string]string{"error": "internal error"})
		}
		return
	}
	writeJSON(w, http.StatusOK, items)
}

func writeJSON(w http.ResponseWriter, status int, v any) {
	w.Header().Set("Content-Type", "application/json")
	w.WriteHeader(status)
	_ = json.NewEncoder(w).Encode(v)
}