feat(cli): discover ThothII projects and installations

tools/tht/internal/config/discovery.go

@@ -0,0 +1,144 @@
+package config
+
+import (
+	"errors"
+	"fmt"
+	"os"
+	"path/filepath"
+	"sort"
+	"strings"
+
+	"github.com/aritmolab/thothii/tools/tht/internal/project"
+)
+
+// Resolve selects one installation descriptor without searching arbitrary descendants.
+// Explicit paths and THOTHII_INSTALLATION are authoritative; automatic discovery considers
+// only the current directory, its parents, and immediate deploy/* descriptors.
+func Resolve(explicit string, environment func(string) string, workingDirectory string) (string, error) {
+	if explicit != "" {
+		return validateSelectedPath(explicit, "--installation")
+	}
+	if environment != nil {
+		if value := strings.TrimSpace(environment("THOTHII_INSTALLATION")); value != "" {
+			return validateSelectedPath(value, "THOTHII_INSTALLATION")
+		}
+	}
+
+	friendlyRoot, err := filepath.Abs(workingDirectory)
+	if err != nil {
+		return "", errors.New("installation discovery could not resolve the current directory")
+	}
+	info, err := os.Stat(friendlyRoot)
+	if err != nil || !info.IsDir() {
+		return "", errors.New("installation discovery could not read the current directory")
+	}
+	root, err := project.Discover(friendlyRoot)
+	if err != nil {
+		return "", fmt.Errorf("installation descriptor not found from %s; run tht setup or use --installation <absolute-path>/%s", filepath.Clean(friendlyRoot), installationFileName)
+	}
+	start, err := filepath.EvalSymlinks(friendlyRoot)
+	if err != nil {
+		return "", errors.New("installation discovery could not resolve the current directory")
+	}
+
+	candidates := make(map[string]string)
+	for directory := filepath.Clean(start); ; directory = filepath.Dir(directory) {
+		for _, path := range discoveryCandidates(directory) {
+			if hasArtifactsComponent(path) {
+				continue
+			}
+			info, statErr := os.Stat(path)
+			if statErr != nil || !info.Mode().IsRegular() {
+				continue
+			}
+			if _, loadErr := Load(path); loadErr != nil {
+				continue
+			}
+			canonical := canonicalPath(path)
+			candidates[canonical] = path
+		}
+		if directory == root.Path {
+			break
+		}
+		parent := filepath.Dir(directory)
+		if parent == directory {
+			break
+		}
+	}
+
+	paths := make([]string, 0, len(candidates))
+	for _, path := range candidates {
+		paths = append(paths, path)
+	}
+	sort.Strings(paths)
+	switch len(paths) {
+	case 1:
+		return paths[0], nil
+	case 0:
+		return "", fmt.Errorf("installation descriptor not found from %s; run tht setup or use --installation <absolute-path>/%s", filepath.Clean(friendlyRoot), installationFileName)
+	default:
+		return "", fmt.Errorf("multiple valid installation descriptors found: %s; use --installation <absolute-path>/%s", formatCandidates(paths, root.Path), installationFileName)
+	}
+}
+
+func formatCandidates(paths []string, root string) string {
+	formatted := make([]string, 0, len(paths))
+	for _, path := range paths {
+		id := filepath.Base(filepath.Dir(path))
+		relative, err := filepath.Rel(filepath.Join(root, "deploy"), path)
+		if err == nil {
+			parts := strings.Split(filepath.Clean(relative), string(filepath.Separator))
+			if len(parts) == 2 && parts[1] == installationFileName {
+				id = parts[0]
+			}
+		}
+		formatted = append(formatted, fmt.Sprintf("%s: %s", id, path))
+	}
+	return strings.Join(formatted, ", ")
+}
+
+func validateSelectedPath(path, source string) (string, error) {
+	if !filepath.IsAbs(path) {
+		return "", fmt.Errorf("%s must be an absolute path", source)
+	}
+	path = filepath.Clean(path)
+	if filepath.Base(path) != installationFileName {
+		return "", fmt.Errorf("%s must name %s", source, installationFileName)
+	}
+	if _, err := Load(path); err != nil {
+		return "", fmt.Errorf("%s is unavailable: %w", source, err)
+	}
+	return path, nil
+}
+
+func discoveryCandidates(directory string) []string {
+	candidates := []string{filepath.Join(directory, installationFileName)}
+	deploy := filepath.Join(directory, "deploy")
+	entries, err := os.ReadDir(deploy)
+	if err != nil {
+		return candidates
+	}
+	for _, entry := range entries {
+		if entry.IsDir() {
+			candidates = append(candidates, filepath.Join(deploy, entry.Name(), installationFileName))
+		}
+	}
+	sort.Strings(candidates)
+	return candidates
+}
+
+func canonicalPath(path string) string {
+	if resolved, err := filepath.EvalSymlinks(path); err == nil {
+		return filepath.Clean(resolved)
+	}
+	return filepath.Clean(path)
+}
+
+func hasArtifactsComponent(path string) bool {
+	for _, component := range strings.Split(filepath.Clean(path), string(filepath.Separator)) {
+		if component == ".artifacts" {
+			return true
+		}
+	}
+	return false
+}