package scheduler

import (
	"context"
	"fmt"

	"github.com/robfig/cron/v3"
	"github.com/tradarr/backend/internal/ai"
	"github.com/tradarr/backend/internal/models"
	"github.com/tradarr/backend/internal/scraper"
)

type Scheduler struct {
	cron     *cron.Cron
	registry *scraper.Registry
	pipeline *ai.Pipeline
	repo     *models.Repository
	entryIDs []cron.EntryID
}

func New(registry *scraper.Registry, pipeline *ai.Pipeline, repo *models.Repository) *Scheduler {
	return &Scheduler{
		cron:     cron.New(),
		registry: registry,
		pipeline: pipeline,
		repo:     repo,
	}
}

func (s *Scheduler) Start() error {
	if err := s.loadSchedule(); err != nil {
		return err
	}
	s.cron.Start()
	return nil
}

func (s *Scheduler) Stop() {
	s.cron.Stop()
}

func (s *Scheduler) Reload() error {
	for _, id := range s.entryIDs {
		s.cron.Remove(id)
	}
	s.entryIDs = nil
	return s.loadSchedule()
}

func (s *Scheduler) loadSchedule() error {
	slots, err := s.repo.ListScheduleSlots()
	if err != nil {
		return fmt.Errorf("load schedule: %w", err)
	}
	if len(slots) == 0 {
		fmt.Println("scheduler: no schedule configured, scraping disabled")
		return nil
	}

	for _, slot := range slots {
		// Format cron: "minute hour * * day_of_week"
		spec := fmt.Sprintf("%d %d * * %d", slot.Minute, slot.Hour, slot.DayOfWeek)
		id, err := s.cron.AddFunc(spec, s.run)
		if err != nil {
			fmt.Printf("scheduler: invalid cron spec %q: %v\n", spec, err)
			continue
		}
		s.entryIDs = append(s.entryIDs, id)
	}

	fmt.Printf("scheduler: %d time slots loaded\n", len(s.entryIDs))
	return nil
}

func (s *Scheduler) run() {
	fmt.Println("scheduler: starting scraping cycle")
	if err := s.registry.RunAll(); err != nil {
		fmt.Printf("scheduler scrape error: %v\n", err)
		return
	}
	fmt.Println("scheduler: starting AI summaries")
	if err := s.pipeline.GenerateForAll(context.Background()); err != nil {
		fmt.Printf("scheduler summary error: %v\n", err)
	}
}