package gcp

import (
	"errors"
	"net/http"
	"slices"

	"github.com/go-logr/logr"
	"google.golang.org/api/googleapi"

	"gitea.home.hrajfrisbee.cz/kacerr/egress-proxies-operator/internal/provider"
)

// classify maps a GCP API error onto the provider taxonomy:
// 404 → NotFound; 429 and quota-flavored 403s → QuotaExceeded;
// 400/401/other 403s → Permanent; 408/5xx and anything unrecognized
// (network errors, context cancellation) → Transient, because retrying is
// always safer than latching Failed on an error nobody taught this
// function to recognize.
func classify(err error) error {
	var gerr *googleapi.Error
	if !errors.As(err, &gerr) {
		return provider.ErrTransient
	}
	switch {
	case gerr.Code == http.StatusNotFound:
		return provider.ErrNotFound
	case gerr.Code == http.StatusTooManyRequests:
		return provider.ErrQuotaExceeded
	case gerr.Code == http.StatusForbidden && hasReason(gerr, "quotaExceeded", "rateLimitExceeded"):
		return provider.ErrQuotaExceeded
	case gerr.Code == http.StatusBadRequest,
		gerr.Code == http.StatusUnauthorized,
		gerr.Code == http.StatusForbidden:
		return provider.ErrPermanent
	default:
		return provider.ErrTransient
	}
}

func (p *Provider) wrapErr(op, id string, err error) error {
	return provider.Wrap(classify(err), op, p.name, id, err)
}

// logAPIError records the raw googleapi error shape (HTTP status, reasons)
// at V(1) — classify collapses it onto the coarser provider taxonomy, so
// this line is the only place the original status survives.
func logAPIError(log logr.Logger, op string, err error) {
	if !log.V(1).Enabled() {
		return
	}
	kv := []any{"op", op, "error", err.Error()}
	var gerr *googleapi.Error
	if errors.As(err, &gerr) {
		reasons := make([]string, 0, len(gerr.Errors))
		for _, item := range gerr.Errors {
			reasons = append(reasons, item.Reason)
		}
		kv = append(kv, "httpStatus", gerr.Code, "reasons", reasons)
	}
	log.V(1).Info("GCP API call failed", kv...)
}

func hasReason(gerr *googleapi.Error, reasons ...string) bool {
	for _, item := range gerr.Errors {
		if slices.Contains(reasons, item.Reason) {
			return true
		}
	}
	return false
}

func isAlreadyExists(err error) bool {
	var gerr *googleapi.Error
	return errors.As(err, &gerr) && gerr.Code == http.StatusConflict
}

func isNotFound(err error) bool {
	var gerr *googleapi.Error
	return errors.As(err, &gerr) && gerr.Code == http.StatusNotFound
}