package workspace

import (
	"fmt"
	"path/filepath"
	"strings"

	"gitea.maximumdirect.net/eric/notarius/internal/core/config"
)

type Settings struct {
	RootDir            string
	DiagnosticsRoot    string
	CheckpointsRoot    string
	DebugRoot          string
	DiagnosticsEnabled bool
	ResumeEnabled      bool
	DebugEnabled       bool
}

func FromConfig(cfg config.Config) Settings {
	root := cleanPath(cfg.Workspace.Directory)
	settings := Settings{
		RootDir:            root,
		DiagnosticsEnabled: cfg.DiagnosticsEnabled(),
	}
	if settings.DiagnosticsEnabled {
		settings.DiagnosticsRoot = cleanPath(cfg.Diagnostics.WorkDir)
	}
	if root == "" {
		return settings
	}

	settings.CheckpointsRoot = filepath.Join(root, "checkpoints")
	settings.DebugRoot = filepath.Join(root, "debug")
	settings.ResumeEnabled = cfg.Workspace.Resume.Enabled
	settings.DebugEnabled = cfg.Workspace.Debug.Enabled
	return settings
}

func (s Settings) DiagnosticsRunDirectory(runID string) (string, error) {
	if !s.DiagnosticsEnabled || strings.TrimSpace(s.DiagnosticsRoot) == "" {
		return "", nil
	}
	return safeSingleDirectory(s.DiagnosticsRoot, runID, "diagnostics run ID")
}

func (s Settings) CheckpointIdentityDirectory(identity string) (string, error) {
	if !s.ResumeEnabled || strings.TrimSpace(s.CheckpointsRoot) == "" {
		return "", nil
	}
	return SafePath(s.CheckpointsRoot, identity)
}

func (s Settings) DebugRunDirectory(runID string) (string, error) {
	if !s.DebugEnabled || strings.TrimSpace(s.DebugRoot) == "" {
		return "", nil
	}
	return safeSingleDirectory(s.DebugRoot, runID, "debug run ID")
}

func cleanPath(path string) string {
	path = strings.TrimSpace(path)
	if path == "" {
		return ""
	}
	return filepath.Clean(path)
}

func safeSingleDirectory(root string, name string, label string) (string, error) {
	name = strings.TrimSpace(name)
	if strings.Contains(name, "/") || strings.Contains(name, `\`) {
		return "", fmt.Errorf("%s %q must be a single directory name", label, name)
	}
	return SafePath(root, name)
}