package releasekit

import (
	"context"
	"errors"
	"fmt"
	"strings"

	internalpreparation "gitea.maximumdirect.net/eric/ReleaseKit/internal/preparation"
	"gitea.maximumdirect.net/eric/ReleaseKit/internal/releaseidentity"
)

// TaggedCheckoutRequest selects a full Git tag and the Git object ID expected
// by an external build or CI event. An empty Remote selects origin.
type TaggedCheckoutRequest struct {
	RepositoryDir  string
	Tag            string
	Remote         string
	ExpectedCommit string
	// VerifyOnly checks an already prepared checkout without fetching or checking out.
	VerifyOnly bool
}

// PrepareTaggedCheckout fetches Tag from Remote, verifies that its peeled
// commit matches ExpectedCommit, and checks out that commit detached. When
// VerifyOnly is true, it performs the same tag, HEAD, and cleanliness checks
// without fetching or changing the checkout. It does not publish a tag or
// hosted content.
func PrepareTaggedCheckout(ctx context.Context, request TaggedCheckoutRequest) error {
	return internalpreparation.PrepareTaggedCheckout(ctx, internalpreparation.TaggedCheckoutRequest{
		RepositoryDir:  request.RepositoryDir,
		Tag:            request.Tag,
		Remote:         request.Remote,
		ExpectedCommit: request.ExpectedCommit,
		VerifyOnly:     request.VerifyOnly,
	})
}

// DependencyPreparationRequest selects the repository module whose dependencies
// should be prepared.
type DependencyPreparationRequest struct {
	RepositoryDir string
	// ModuleDir selects a repository-relative module directory; empty selects
	// the repository root.
	ModuleDir string
}

// PrepareBuildDependencies runs `go mod download` in the selected module with
// workspace discovery disabled and the locally available compatible Go
// toolchain selected. It may access module networks and updates the Go module
// cache using the caller's Go proxy, private-module, credential, and cache
// settings. If required checksums are missing, the Go command may update
// go.sum. Cancellation and Go command failures are returned to the caller.
func PrepareBuildDependencies(ctx context.Context, request DependencyPreparationRequest) error {
	if strings.TrimSpace(request.RepositoryDir) == "" {
		return errors.New("repository directory is required")
	}
	selection, err := releaseidentity.ResolveSelection(request.RepositoryDir, request.ModuleDir)
	if err != nil {
		return fmt.Errorf("resolve dependency preparation module: %w", err)
	}
	return internalpreparation.PrepareBuildDependencies(ctx, selection.ModuleDir)
}