// Copyright (c) 2026 Storm Dragon
// SPDX-License-Identifier: GPL-3.0-or-later

package app

import (
	"errors"
	"slices"

	"git.stormux.org/storm/cthulhu/internal/tentacle"
)

func change_tentacle_repositories(repositories []tentacle.Repository, request tentacle.ManagementRequest, repository *tentacle.Repository) ([]tentacle.Repository, error) {
	if request.Entry != nil || request.ID != "" {
		return nil, errors.New("unexpected tentacle entry in repository request")
	}
	origin, err := tentacle.RepositoryURL(request.URL)
	if err != nil {
		return nil, err
	}
	next := tentacle.CloneRepositories(repositories)
	index := slices.IndexFunc(next, func(value tentacle.Repository) bool { return value.URL == origin })
	switch request.Action {
	case "repository-add", "repository-refresh":
		if repository == nil || repository.URL != origin {
			return nil, errors.New("validated repository metadata is required")
		}
		candidate := tentacle.CloneRepositories([]tentacle.Repository{*repository})[0]
		if request.Action == "repository-add" {
			if index >= 0 {
				return nil, errors.New("repository already added")
			}
			next = append(next, candidate)
		} else {
			if index < 0 {
				return nil, errors.New("repository does not exist")
			}
			if next[index].ID != repository.ID {
				return nil, errors.New("repository identity changed; the previous catalog was retained")
			}
			next[index] = candidate
		}
	case "repository-remove":
		if index < 0 {
			return nil, errors.New("repository does not exist")
		}
		next = slices.Delete(next, index, index+1)
	default:
		return nil, errors.New("unknown repository operation")
	}
	return next, tentacle.ValidateRepositories(next)
}