package publish

import (
	"context"
	"fmt"
	"os"
	"path/filepath"

	"git.thokra.dev/thokra/stamp/internal/config"
	"git.thokra.dev/thokra/stamp/internal/git"
	giteaClient "git.thokra.dev/thokra/stamp/internal/gitea"
	ghClient "git.thokra.dev/thokra/stamp/internal/github"
)

// Options controls publish behaviour.
type Options struct {
	DryRun   bool
	RepoSlug string // "owner/repo" — required for releases
	RepoRoot string
}

// Publish creates tags, releases, and uploads artifacts for a project.
func Publish(cfg *config.Config, project *config.Project, opts Options) error {
	tag := git.TagName(project.Name, project.Version)

	// --- Git tag ---
	if project.Publish.PublishTags() {
		if opts.DryRun {
			fmt.Printf("[dry-run] would create git tag %s\n", tag)
		} else {
			exists, err := git.TagExists(opts.RepoRoot, tag)
			if err != nil {
				return err
			}
			if exists {
				fmt.Printf("tag %s already exists, skipping\n", tag)
			} else {
				if err := git.Tag(opts.RepoRoot, tag, fmt.Sprintf("release %s %s", project.Name, project.Version)); err != nil {
					return fmt.Errorf("creating tag %s: %w", tag, err)
				}
				if err := git.PushTag(opts.RepoRoot, tag); err != nil {
					return fmt.Errorf("pushing tag %s: %w", tag, err)
				}
				fmt.Printf("created and pushed tag %s\n", tag)
			}
		}
	}

	if !project.Publish.PublishReleases() {
		return nil
	}

	if opts.RepoSlug == "" {
		return fmt.Errorf("STAMP_REPO (owner/repo) must be set to publish releases")
	}

	// --- Collect artifact paths ---
	var artifacts []string
	for _, pattern := range project.Publish.Artifacts {
		matches, err := filepath.Glob(filepath.Join(opts.RepoRoot, pattern))
		if err != nil {
			return fmt.Errorf("glob %q: %w", pattern, err)
		}
		artifacts = append(artifacts, matches...)
	}

	releaseTitle := fmt.Sprintf("%s v%s", project.Name, project.Version)
	releaseBody := fmt.Sprintf("Release of %s version %s", project.Name, project.Version)

	// Detect host: GitHub vs Gitea
	if isGitea() {
		if err := publishGitea(opts, tag, releaseTitle, releaseBody, artifacts); err != nil {
			return err
		}
	} else {
		if err := publishGitHub(opts, tag, releaseTitle, releaseBody, artifacts); err != nil {
			return err
		}
	}

	return nil
}

func publishGitHub(opts Options, tag, title, body string, artifacts []string) error {
	client, err := ghClient.NewClient(opts.RepoSlug)
	if err != nil {
		return err
	}

	ctx := context.Background()

	if opts.DryRun {
		fmt.Printf("[dry-run] would create GitHub release %s with %d artifact(s)\n", tag, len(artifacts))
		return nil
	}

	releaseID, err := client.CreateRelease(ctx, tag, title, body, false, false)
	if err != nil {
		return err
	}
	fmt.Printf("created GitHub release %s (id=%d)\n", tag, releaseID)

	for _, a := range artifacts {
		if err := client.UploadAsset(ctx, releaseID, a); err != nil {
			return err
		}
		fmt.Printf("uploaded artifact: %s\n", a)
	}
	return nil
}

func publishGitea(opts Options, tag, title, body string, artifacts []string) error {
	client, err := giteaClient.NewClient(opts.RepoSlug)
	if err != nil {
		return err
	}

	if opts.DryRun {
		fmt.Printf("[dry-run] would create Gitea release %s with %d artifact(s)\n", tag, len(artifacts))
		return nil
	}

	releaseID, err := client.CreateRelease(tag, title, body, false, false)
	if err != nil {
		return err
	}
	fmt.Printf("created Gitea release %s (id=%d)\n", tag, releaseID)

	for _, a := range artifacts {
		if err := client.UploadAsset(releaseID, a); err != nil {
			return err
		}
		fmt.Printf("uploaded artifact: %s\n", a)
	}
	return nil
}

// isGitea returns true when Gitea environment variables are configured.
func isGitea() bool {
	return os.Getenv("GITEA_BASE_URL") != ""
}