package main

import (
	"fmt"

	"gopkg.in/urfave/cli.v2"

	"github.com/ipfs/go-cid"

	"github.com/filecoin-project/lotus/chain/types"
	lcli "github.com/filecoin-project/lotus/cli"
)

var staterootStatsCmd = &cli.Command{
	Name:        "stateroot-stats",
	Description: "Walk down the chain and collect stats-obj changes between tipsets",
	Flags: []cli.Flag{
		&cli.StringFlag{
			Name:  "tipset",
			Usage: "specify tipset to start from",
		},
		&cli.IntFlag{
			Name:  "count",
			Usage: "number of tipsets to count back",
			Value: 30,
		},
		&cli.BoolFlag{
			Name:  "diff",
			Usage: "compare tipset with previous",
			Value: false,
		},
	},
	Action: func(cctx *cli.Context) error {
		api, closer, err := lcli.GetFullNodeAPI(cctx)
		if err != nil {
			return err
		}

		defer closer()
		ctx := lcli.ReqContext(cctx)

		ts, err := lcli.LoadTipSet(ctx, cctx, api)
		if err != nil {
			return err
		}

		if ts == nil {
			ts, err = api.ChainHead(ctx)
			if err != nil {
				return err
			}
		}

		fn := func(ts *types.TipSet) (cid.Cid, []cid.Cid) {
			blk := ts.Blocks()[0]
			strt := blk.ParentStateRoot
			cids := blk.Parents

			return strt, cids
		}

		count := cctx.Int("count")
		diff := cctx.Bool("diff")

		fmt.Printf("Height\tSize\tLinks\tObj\tBase\n")
		for i := 0; i < count; i++ {
			if ts.Height() == 0 {
				return nil
			}
			strt, cids := fn(ts)

			k := types.NewTipSetKey(cids...)
			ts, err = api.ChainGetTipSet(ctx, k)
			if err != nil {
				return err
			}

			pstrt, _ := fn(ts)

			if !diff {
				pstrt = cid.Undef
			}

			stats, err := api.ChainStatObj(ctx, strt, pstrt)
			if err != nil {
				return err
			}

			fmt.Printf("%d\t%d\t%d\t%s\t%s\n", ts.Height(), stats.Size, stats.Links, strt, pstrt)
		}

		return nil
	},
}