package aplicare

import (
	"api-service/internal/config"
	"context"
	"fmt"
	"time"
)

type SyncResult struct {
	RunAt      string   `json:"run_at"`
	TotalRooms int      `json:"total_rooms"`
	Changed    int      `json:"changed"`
	Posted     int      `json:"posted"`
	Errors     []string `json:"errors,omitempty"`
	DryRun     bool     `json:"dry_run"`
}

type Syncer struct {
	simrs     *SimrsDB
	bpjs      *BpjsClient
	statePath string
	dryRun    bool
}

func NewSyncer(simrs *SimrsDB, cfg *config.Config, statePath string, dryRun bool) *Syncer {
	return &Syncer{
		simrs:     simrs,
		bpjs:      NewBpjsClient(cfg.Bpjs),
		statePath: statePath,
		dryRun:    dryRun,
	}
}

func (s *Syncer) Sync(ctx context.Context) (*SyncResult, error) {
	result := &SyncResult{
		RunAt:  time.Now().Format(time.RFC3339),
		DryRun: s.dryRun,
	}

	// 1. Baca dari SIMRS
	ruangans, err := s.simrs.GetRuangan(ctx)
	if err != nil {
		return nil, fmt.Errorf("baca m_ruang gagal: %w", err)
	}

	detailMap, err := s.simrs.GetBedDetails(ctx)
	if err != nil {
		return nil, fmt.Errorf("baca m_detail gagal: %w", err)
	}

	// 2. Transform
	beds := buildBedData(ruangans, detailMap)
	result.TotalRooms = len(beds)

	// 3. Diff vs state lama
	oldState, err := LoadState(s.statePath)
	if err != nil || oldState == nil {
		oldState = &State{Rooms: make(map[string]RoomState)}
	}

	newState := ComputeDiff(oldState, beds)
	changedBeds := GetChangedBeds(newState, beds)
	result.Changed = len(changedBeds)

	// 4. Dry run — tampilkan perubahan di terminal
	if s.dryRun {
		if len(changedBeds) == 0 {
			fmt.Println("[DRY RUN] Tidak ada perubahan")
		} else {
			fmt.Printf("[DRY RUN] %d ruangan berubah:\n", len(changedBeds))
			for _, bed := range changedBeds {
				old := newState.Rooms[bed.KodeRuang].OldValue
				fmt.Printf("  → %-30s | kelas: %-6s | kapasitas: %d | tersedia: %d → %d\n",
					bed.NamaRuang,
					bed.KodeKelas,
					bed.Kapasitas,
					old.Tersedia,
					bed.Tersedia,
				)
				result.Posted++
			}
		}
		if err := SaveState(s.statePath, newState); err != nil {
			result.Errors = append(result.Errors, fmt.Sprintf("simpan state gagal: %v", err))
		}
		WriteBatchLog(result)
		return result, nil
	}

	// 5. POST ke BPJS hanya yang berubah
	if len(changedBeds) > 0 {
		fmt.Printf("[SYNC] %d ruangan akan dikirim ke BPJS:\n", len(changedBeds))
	}

	for _, bed := range changedBeds {
		if bed.Kapasitas == 0 {
			continue
		}

		oldTersedia := newState.Rooms[bed.KodeRuang].OldValue.Tersedia

		start := time.Now()
		err := s.bpjs.PostKamar(ctx, bed)
		elapsed := time.Since(start).Milliseconds()

		if err != nil {
			msg := fmt.Sprintf("POST %s gagal: %v", bed.KodeRuang, err)
			result.Errors = append(result.Errors, msg)
			fmt.Printf("  → %-30s | kelas: %-6s | tersedia: %d → %d | [GAGAL] %v\n",
				bed.NamaRuang, bed.KodeKelas, oldTersedia, bed.Tersedia, err)
			WriteLog(SyncLog{
				KodeRuang:  bed.KodeRuang,
				NamaRuang:  bed.NamaRuang,
				KodeKelas:  bed.KodeKelas,
				Kapasitas:  bed.Kapasitas,
				Tersedia:   bed.Tersedia,
				Action:     "post",
				Status:     "gagal",
				Error:      err.Error(),
				ResponseMs: elapsed,
			})
			continue
		}

		fmt.Printf("  → %-30s | kelas: %-6s | tersedia: %d → %d | [SUKSES] %dms\n",
			bed.NamaRuang, bed.KodeKelas, oldTersedia, bed.Tersedia, elapsed)
		WriteLog(SyncLog{
			KodeRuang:  bed.KodeRuang,
			NamaRuang:  bed.NamaRuang,
			KodeKelas:  bed.KodeKelas,
			Kapasitas:  bed.Kapasitas,
			Tersedia:   bed.Tersedia,
			Action:     "post",
			Status:     "sukses",
			ResponseMs: elapsed,
		})

		result.Posted++

		if room, ok := newState.Rooms[bed.KodeRuang]; ok {
			room.OldValue = room.NewValue
			room.Changed = false
			room.LastSynced = time.Now().Format(time.RFC3339)
			newState.Rooms[bed.KodeRuang] = room
		}
	}

	// 6. Simpan state
	if err := SaveState(s.statePath, newState); err != nil {
		result.Errors = append(result.Errors, fmt.Sprintf("simpan state gagal: %v", err))
	}

	// 7. Tulis ringkasan ke log
	WriteBatchLog(result)

	return result, nil
}