// Copyright 2015 The go-ethereum Authors
// This file is part of the go-ethereum library.
//
// The go-ethereum library is free software: you can redistribute it and/or modify
// it under the terms of the GNU Lesser General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// The go-ethereum library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public License
// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.

//go:build integration

package tests

import (
	"bufio"
	"bytes"
	"context"
	"fmt"
	"reflect"
	"runtime"
	"testing"

	"github.com/ledgerwatch/erigon-lib/kv/memdb"
	"github.com/ledgerwatch/erigon/core/vm"
	"github.com/ledgerwatch/erigon/eth/tracers/logger"
	"github.com/ledgerwatch/log/v3"
)

func TestState(t *testing.T) {
	defer log.Root().SetHandler(log.Root().GetHandler())
	log.Root().SetHandler(log.LvlFilterHandler(log.LvlError, log.StderrHandler))
	if runtime.GOOS == "windows" {
		t.Skip("fix me on win please") // it's too slow on win, need generally improve speed of this tests
	}
	//t.Parallel()

	st := new(testMatcher)

	// EOF is not implemented yet
	st.skipLoad(`^EIPTests/stEOF/`)

	// Very time consuming
	st.skipLoad(`^stTimeConsuming/`)
	st.skipLoad(`.*vmPerformance/loop.*`)

	st.walk(t, stateTestDir, func(t *testing.T, name string, test *StateTest) {
		db := memdb.NewTestDB(t)
		for _, subtest := range test.Subtests() {
			subtest := subtest
			key := fmt.Sprintf("%s/%d", subtest.Fork, subtest.Index)
			t.Run(key, func(t *testing.T) {
				withTrace(t, func(vmconfig vm.Config) error {
					tx, err := db.BeginRw(context.Background())
					if err != nil {
						t.Fatal(err)
					}
					defer tx.Rollback()
					_, err = test.Run(tx, subtest, vmconfig)
					tx.Rollback()
					if err != nil && len(test.json.Post[subtest.Fork][subtest.Index].ExpectException) > 0 {
						// Ignore expected errors
						return nil
					}
					return st.checkFailure(t, err)
				})
			})
		}
	})
}

func withTrace(t *testing.T, test func(vm.Config) error) {
	// Use config from command line arguments.
	config := vm.Config{}
	err := test(config)
	if err == nil {
		return
	}

	// Test failed, re-run with tracing enabled.
	t.Error(err)
	buf := new(bytes.Buffer)
	w := bufio.NewWriter(buf)
	tracer := logger.NewJSONLogger(&logger.LogConfig{DisableMemory: true}, w)
	config.Debug, config.Tracer = true, tracer
	err2 := test(config)
	if !reflect.DeepEqual(err, err2) {
		t.Errorf("different error for second run: %v", err2)
	}
	w.Flush()
	if buf.Len() == 0 {
		t.Log("no EVM operation logs generated")
	} else {
		t.Log("EVM operation log:\n" + buf.String())
	}
	//t.Logf("EVM output: 0x%x", tracer.Output())
	//t.Logf("EVM error: %v", tracer.Error())
}