package app

import (
	"encoding/json"
	"fmt"
	"os"
	"time"

	"github.com/andyleap/hnh-map/internal/app/store"
	"go.etcd.io/bbolt"
)

type zoomproc struct {
	c Coord
	m int
}

func (a *App) doRebuildZooms() {
	needProcess := map[zoomproc]struct{}{}
	saveGrid := map[zoomproc]string{}

	a.db.Update(func(tx *bbolt.Tx) error {
		b := tx.Bucket(store.BucketGrids)
		if b == nil {
			return nil
		}
		b.ForEach(func(k, v []byte) error {
			grid := GridData{}
			json.Unmarshal(v, &grid)
			needProcess[zoomproc{grid.Coord.Parent(), grid.Map}] = struct{}{}
			saveGrid[zoomproc{grid.Coord, grid.Map}] = grid.ID
			return nil
		})
		tx.DeleteBucket(store.BucketTiles)
		return nil
	})

	for g, id := range saveGrid {
		f := fmt.Sprintf("%s/grids/%s.png", a.gridStorage, id)
		if _, err := os.Stat(f); err != nil {
			continue
		}
		a.SaveTile(g.m, g.c, 0, fmt.Sprintf("grids/%s.png", id), time.Now().UnixNano())
	}
	for z := 1; z <= 5; z++ {
		process := needProcess
		needProcess = map[zoomproc]struct{}{}
		for p := range process {
			a.updateZoomLevel(p.m, p.c, z)
			needProcess[zoomproc{p.c.Parent(), p.m}] = struct{}{}
		}
	}
}