package http

import (
	"context"
	"errors"
	"net/http"
	"strings"

	"primaya-api/cpone-middleware/internal/databaseconfig"
	"primaya-api/cpone-middleware/internal/repository"
)

type selectedRepositoryKey struct{}

type DatabaseResolver interface {
	Resolve(ctx context.Context, code string) (repository.MySQLLayananRepository, error)
}

func BearerAuth(staticToken string, next http.Handler) http.Handler {
	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		if bearerToken(r.Header.Get("Authorization")) != staticToken {
			WriteJSON(w, http.StatusUnauthorized, Response{
				Success: false,
				Message: "Unauthenticated.",
				Data:    nil,
			})
			return
		}

		next.ServeHTTP(w, r)
	})
}

func SelectDatabase(resolver DatabaseResolver, next http.Handler) http.Handler {
	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		code := strings.TrimSpace(r.Header.Get("X-RS-Code"))
		if code == "" {
			code = strings.TrimSpace(r.URL.Query().Get("kode_rs"))
		}
		if code == "" {
			WriteJSON(w, http.StatusUnprocessableEntity, Response{Success: false,
				Message: "Kode RS wajib diisi melalui header X-RS-Code atau parameter kode_rs", Data: nil})
			return
		}
		code = databaseconfig.NormalizeRSCode(code)

		repo, err := resolver.Resolve(r.Context(), code)
		if err != nil {
			if errors.Is(err, databaseconfig.ErrRSCodeMismatch) {
				WriteJSON(w, http.StatusForbidden, Response{Success: false,
					Message: "X-RS-Code tidak sesuai dengan instance CPONE", Data: nil})
				return
			}
			WriteJSON(w, http.StatusServiceUnavailable, Response{Success: false,
				Message: "Database HIS tidak dapat diakses", Data: nil})
			return
		}
		w.Header().Set("X-RS-Code", code)
		ctx := context.WithValue(r.Context(), selectedRepositoryKey{}, repo)
		next.ServeHTTP(w, r.WithContext(ctx))
	})
}

func selectedRepository(ctx context.Context) (repository.MySQLLayananRepository, bool) {
	repo, ok := ctx.Value(selectedRepositoryKey{}).(repository.MySQLLayananRepository)
	return repo, ok
}

func bearerToken(header string) string {
	const prefix = "Bearer "
	if !strings.HasPrefix(header, prefix) {
		return ""
	}

	return strings.TrimSpace(strings.TrimPrefix(header, prefix))
}