package main

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

	ops "fn-registry/fn_operations"
)

// listProjectDirs returns subdirectories under projectsDir.
func listProjectDirs(projectsDir string) ([]ProjectInfo, error) {
	log.Printf("[listProjectDirs] scanning %s", projectsDir)

	entries, err := os.ReadDir(projectsDir)
	if err != nil {
		if os.IsNotExist(err) {
			log.Printf("[listProjectDirs] dir does not exist, returning nil")
			return nil, nil
		}
		log.Printf("[listProjectDirs] ERROR reading dir: %v", err)
		return nil, err
	}

	log.Printf("[listProjectDirs] found %d entries", len(entries))

	var projects []ProjectInfo
	for _, e := range entries {
		log.Printf("[listProjectDirs]   entry: %s isDir=%v", e.Name(), e.IsDir())
		if !e.IsDir() {
			continue
		}
		dbPath := filepath.Join(projectsDir, e.Name(), "operations.db")
		if _, err := os.Stat(dbPath); err != nil {
			log.Printf("[listProjectDirs]   %s: no operations.db, skipping", e.Name())
			continue
		}

		info := ProjectInfo{Name: e.Name()}

		// Quick counts from the DB
		db, err := ops.Open(dbPath)
		if err == nil {
			entities, _ := db.ListEntities("", "")
			relations, _ := db.ListRelations("")
			info.EntityCount = len(entities)
			info.RelCount = len(relations)
			db.Close()
			log.Printf("[listProjectDirs]   %s: OK (entities=%d relations=%d)", e.Name(), info.EntityCount, info.RelCount)
		} else {
			log.Printf("[listProjectDirs]   %s: ERROR opening db: %v", e.Name(), err)
		}

		projects = append(projects, info)
	}

	log.Printf("[listProjectDirs] returning %d projects", len(projects))
	return projects, nil
}

// createProject creates a new project directory with an operations.db.
func createProject(projectsDir, name string) error {
	dir := filepath.Join(projectsDir, name)
	log.Printf("[createProject] creating dir: %s", dir)

	if err := os.MkdirAll(dir, 0o755); err != nil {
		log.Printf("[createProject] ERROR mkdir: %v", err)
		return fmt.Errorf("creating project directory: %w", err)
	}

	dbPath := filepath.Join(dir, "operations.db")
	log.Printf("[createProject] creating db: %s", dbPath)

	db, err := ops.Open(dbPath)
	if err != nil {
		log.Printf("[createProject] ERROR opening db: %v", err)
		return fmt.Errorf("creating operations.db: %w", err)
	}

	if err := db.Close(); err != nil {
		log.Printf("[createProject] ERROR closing db: %v", err)
		return err
	}

	// Verify
	if fi, err := os.Stat(dbPath); err != nil {
		log.Printf("[createProject] WARNING: db not found after creation: %v", err)
	} else {
		log.Printf("[createProject] OK: db created, size=%d bytes", fi.Size())
	}

	return nil
}

// deleteProject removes a project directory and its operations.db.
func deleteProject(projectsDir, name string) error {
	dir := filepath.Join(projectsDir, name)
	log.Printf("[deleteProject] removing: %s", dir)
	return os.RemoveAll(dir)
}