// Copyright © 2023 Ory Corp
// SPDX-License-Identifier: Apache-2.0

package relationtuple

import (
	"context"
	"net/http"

	"connectrpc.com/connect"
	"github.com/ory/herodot"
	keysetpagination "github.com/ory/x/pagination/keysetpagination_v2"

	rts "github.com/ory/keto/gen/go/ory/keto/relation_tuples/v1alpha2"
	"github.com/ory/keto/gen/go/ory/keto/relation_tuples/v1alpha2/relationtuplesconnect"
	"github.com/ory/keto/ketoapi"
)

var _ relationtuplesconnect.ReadServiceHandler = (*ReadHandler)(nil)

type (
	queryWrapper struct {
		*rts.RelationQuery
	}
	deprecatedQueryWrapper struct {
		*rts.ListRelationTuplesRequest_Query
	}
)

func (q *queryWrapper) GetObject() *string    { return q.Object }
func (q *queryWrapper) GetNamespace() *string { return q.Namespace }
func (q *queryWrapper) GetRelation() *string  { return q.Relation }

func (q *deprecatedQueryWrapper) GetObject() *string {
	if q.Object == "" {
		return nil
	}
	return new(q.Object)
}

func (q *deprecatedQueryWrapper) GetNamespace() *string {
	if q.Namespace == "" {
		return nil
	}
	return new(q.Namespace)
}

func (q *deprecatedQueryWrapper) GetRelation() *string {
	if q.Relation == "" {
		return nil
	}
	return new(q.Relation)
}

func (h *ReadHandler) ListRelationTuples(ctx context.Context, req *connect.Request[rts.ListRelationTuplesRequest]) (*connect.Response[rts.ListRelationTuplesResponse], error) {
	var q ketoapi.RelationQuery

	switch {
	case req.Msg.RelationQuery != nil:
		q.FromDataProvider(&queryWrapper{req.Msg.RelationQuery})
	case req.Msg.Query != nil: //nolint:staticcheck //lint:ignore SA1019 backwards compatibility
		q.FromDataProvider(&deprecatedQueryWrapper{req.Msg.Query}) //nolint:staticcheck //lint:ignore SA1019 backwards compatibility
	default:
		return nil, herodot.ErrBadRequest().WithError("you must provide a query")
	}

	iq, err := h.d.ReadOnlyMapper().FromQuery(ctx, &q)
	if err != nil {
		return nil, err
	}

	paginationKeys := h.d.Config(ctx).PaginationEncryptionKeys()
	pageOpts := make([]keysetpagination.Option, 0, 2)
	if req.Msg.PageSize > 0 {
		pageOpts = append(pageOpts, keysetpagination.WithSize(int(req.Msg.PageSize)))
	}
	if req.Msg.PageToken != "" {
		token, err := keysetpagination.ParsePageToken(paginationKeys, req.Msg.PageToken)
		if err != nil {
			return nil, herodot.ErrBadRequest().WithError(err.Error())
		}
		pageOpts = append(pageOpts, keysetpagination.WithToken(token))
	}
	ir, nextPage, err := h.d.RelationTupleManager().GetRelationTuples(ctx, iq, pageOpts...)
	if err != nil {
		return nil, err
	}
	relations, err := h.d.ReadOnlyMapper().ToTuple(ctx, ir...)
	if err != nil {
		return nil, err
	}

	resp := &rts.ListRelationTuplesResponse{
		RelationTuples: make([]*rts.RelationTuple, len(ir)),
	}
	if !nextPage.IsLast() {
		resp.NextPageToken = nextPage.PageToken().Encrypt(paginationKeys)
	}
	for i, r := range relations {
		resp.RelationTuples[i] = r.ToProto()
	}

	return connect.NewResponse(resp), nil
}

// swagger:route GET /relation-tuples relationship getRelationships
//
// # Query relationships
//
// Get all relationships that match the query. Only the namespace field is required.
//
//	Consumes:
//	-  application/x-www-form-urlencoded
//
//	Produces:
//	- application/json
//
//	Schemes: http, https
//
//	Responses:
//	  200: relationships
//	  404: errorGeneric
//	  default: errorGeneric
//
//	Extensions:
//	  x-ory-ratelimit-bucket: keto-admin-medium
func (h *ReadHandler) getRelations(w http.ResponseWriter, r *http.Request) {
	ctx := r.Context()

	q := r.URL.Query()
	query, err := (&ketoapi.RelationQuery{}).FromURLQuery(q)
	if err != nil {
		h.d.Writer().WriteError(w, r, herodot.ErrBadRequest().WithError(err.Error()))
		return
	}

	l := h.d.Logger()
	for k := range q {
		l = l.WithField(k, q.Get(k))
	}
	l.Debug("querying relationships")

	paginationKeys := h.d.Config(ctx).PaginationEncryptionKeys()
	paginationOpts, err := keysetpagination.ParseQueryParams(paginationKeys, q)
	if err != nil {
		h.d.Writer().WriteError(w, r, herodot.ErrBadRequest().WithError(err.Error()))
		return
	}

	iq, err := h.d.ReadOnlyMapper().FromQuery(ctx, query)
	if err != nil {
		h.d.Writer().WriteError(w, r, err)
		return
	}
	ir, nextPage, err := h.d.RelationTupleManager().GetRelationTuples(ctx, iq, paginationOpts...)
	if err != nil {
		h.d.Writer().WriteError(w, r, err)
		return
	}

	relations, err := h.d.ReadOnlyMapper().ToTuple(ctx, ir...)
	if err != nil {
		h.d.Writer().WriteError(w, r, err)
		return
	}

	resp := &ketoapi.GetResponse{
		RelationTuples: relations,
	}
	if !nextPage.IsLast() {
		resp.NextPageToken = nextPage.PageToken().Encrypt(paginationKeys)
	}

	h.d.Writer().Write(w, r, resp)
}