package watchdog

import (
	"log/slog"
	"orbits-server/internal/server/bootstrap"
	"orbits-server/internal/server/database"
	"time"

	"gorm.io/gorm"
)

type State struct {
	FS map[string]struct{}
	DB map[string]database.File
}

type Result struct {
	FSOrphans []string
	DBOrphans []database.File
}

func Kickoff(env bootstrap.Environment, db *gorm.DB) {
	interval := time.Second * time.Duration(env.WatchdogInterval)
	ticker := time.NewTicker(interval)

	go func() {
		defer ticker.Stop()

		run(env, db)

		running := false
		for range ticker.C {
			if running {
				slog.Warn("watchdog is still running, skipping tick")
				continue
			}

			running = true

			func() {
				defer func() { running = false }()
				run(env, db)
			}()
		}
	}()
}

// the watchdog has 2 tasks
// 1 revoke expires keys
// 2 remove / sync orphaned files/db records
func run(env bootstrap.Environment, db *gorm.DB) {
	slog.Debug("watchdog cycle start")

	revokeExpired(db)

	fsState, err := scanFS(env)
	if err != nil {
		slog.Error("scanFS failed", "error", err)
		return
	}

	dbState, err := scanDB(db)
	if err != nil {
		slog.Error("scanDB failed", "error", err)
		return
	}

	result := reconcile(fsState, dbState)

	if len(result.FSOrphans) > 0 {
		slog.Info("filesystem orphans detected")
		applyFS(env, db, result.FSOrphans)
	}

	if len(result.DBOrphans) > 0 {
		slog.Info("database orphans detected")
		applyDB(db, result.DBOrphans)
	}
}