// Copyright 2020 ConsenSys AG
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

package main

import (
	"fmt"
	"gnark-ed25519/poseidon"
	"math/big"
	"time"

	"github.com/consensys/gnark-crypto/ecc"
	"github.com/consensys/gnark/backend/groth16"
	"github.com/consensys/gnark/frontend"
	"github.com/consensys/gnark/frontend/cs/r1cs"
	"github.com/consensys/gnark/test"
)

// type Eddsa25519Circuit struct {
// 	M   []frontend.Variable
// 	Pk  []frontend.Variable
// 	Sig []frontend.Variable
// }

// func (circuit *Eddsa25519Circuit) Define(api frontend.API) error {
// 	c, err := edwards_curve.New[edwards_curve.Ed25519, edwards_curve.Ed25519Scalars](api)
// 	if err != nil {
// 		return err
// 	}
// 	edwards_curve.CheckValid(c, circuit.Sig, circuit.M, circuit.Pk)
// 	return nil
// }

// type Sha512Circuit struct {
// 	in  []frontend.Variable `gnark:"in"`
// 	out []frontend.Variable `gnark:"out"`
// }

// func (circuit *Sha512Circuit) Define(api frontend.API) error {
// 	res := sha512.Sha512(api, circuit.in)
// 	if len(res) != 512 {
// 		panic("bad length")
// 	}
// 	for i := 0; i < 512; i++ {
// 		api.AssertIsEqual(res[i], circuit.out[i])
// 	}
// 	return nil
// }

// func main() {
// 	err := mainImpl()
// 	if err != nil {
// 		fmt.Println(err)
// 		os.Exit(1)
// 	}
// }

// // func mainImpl() error {
// //     in := bytesToBits([]byte("Succinct Labs"))
// //     out := hexToBits("503ace098aa03f6feec1b5df0a38aee923f744a775508bc81f2b94ad139be297c2e8cd8c44af527b5d3f017a7fc929892c896604047e52e3f518924f52bff0dc")

// //     myCircuit := Sha512Circuit{
// //         in,
// //         out,
// //     }
// //     fmt.Println(time.Now(), "compiling...")
// //     r1cs, err := frontend.Compile(ecc.BN254.ScalarField(), r1cs.NewBuilder, &myCircuit)
// //     if err != nil {
// //         return err
// //     }

// //     assignment := &Sha512Circuit{
// //         in,
// //         out,
// //     }
// //     fmt.Println(time.Now(), "generating witness...")
// //     witness, _ := frontend.NewWitness(assignment, ecc.BN254.ScalarField())
// //     publicWitness, _ := witness.Public()
// //     fmt.Println(time.Now(), "groth setup...")
// //     pk, vk, err := groth16.Setup(r1cs)
// //     fmt.Println(time.Now(), "groth prove...")
// //     proof, err := groth16.Prove(r1cs, pk, witness)
// //     fmt.Println(time.Now(), "groth verify...")
// //     err = groth16.Verify(proof, vk, publicWitness)
// //     if err != nil {
// //         return err
// //     }
// //     fmt.Println(proof)
// //     return nil
// // }

// func mainImpl() error {
// 	M := "53756363696e6374204c616273"
// 	Pk := "f7ec1c43f4de9d49556de87b86b26a98942cb078486fdb44de38b80864c39731"
// 	Sig := "35c323757c20640a294345c89c0bfcebe3d554fdb0c7b7a0bdb72222c531b1ec849fed99a053e0f5b02dd9a25bb6eb018885526d9f583cdbde0b1e9f6329da09"

// 	myCircuit := Eddsa25519Circuit{
// 		M:   hexToBits(M),
// 		Pk:  hexToBits(Pk),
// 		Sig: hexToBits(Sig),
// 	}
// 	fmt.Println(time.Now(), "compiling...")
// 	r1cs, err := frontend.Compile(ecc.BN254.ScalarField(), r1cs.NewBuilder, &myCircuit)
// 	if err != nil {
// 		return err
// 	}

// 	assignment := &Eddsa25519Circuit{
// 		M:   hexToBits(M),
// 		Pk:  hexToBits(Pk),
// 		Sig: hexToBits(Sig),
// 	}
// 	fmt.Println(time.Now(), "generating witness...")
// 	witness, _ := frontend.NewWitness(assignment, ecc.BN254.ScalarField())
// 	publicWitness, _ := witness.Public()
// 	fmt.Println(time.Now(), "groth setup...")
// 	pk, vk, err := groth16.Setup(r1cs)
// 	fmt.Println(time.Now(), "groth prove...")
// 	proof, err := groth16.Prove(r1cs, pk, witness)
// 	fmt.Println(time.Now(), "groth verify...")
// 	err = groth16.Verify(proof, vk, publicWitness)
// 	if err != nil {
// 		return err
// 	}
// 	fmt.Println(proof)
// 	return nil
// }

// func hexToBits(h string) []frontend.Variable {
// 	b, err := hex.DecodeString(h)
// 	if err != nil {
// 		panic(err)
// 	}
// 	result := make([]frontend.Variable, len(b)*8)
// 	for i, v := range b {
// 		for j := 0; j < 8; j++ {
// 			if (v & (1 << j)) != 0 {
// 				result[i*8+j] = 1
// 			} else {
// 				result[i*8+j] = 0
// 			}
// 		}
// 	}
// 	return result
// }

// func bytesToBits(arr []byte) []frontend.Variable {
// 	result := make([]frontend.Variable, len(arr)*8)
// 	for i, v := range arr {
// 		for j := 0; j < 8; j++ {
// 			if (v & (1 << (7 - j))) != 0 {
// 				result[i*8+j] = 1
// 			} else {
// 				result[i*8+j] = 0
// 			}
// 		}
// 	}
// 	return result
// }

type PoseidonCircuit struct {
	In  [12]frontend.Variable
	Out [12]frontend.Variable
}

func (circuit *PoseidonCircuit) Define(api frontend.API) error {
	poseidon.Poseidon(api, circuit.In, circuit.Out)
	return nil
}

func main() {
	in_str := [12]string{
		"0",
		"0",
		"0",
		"0",
		"0",
		"0",
		"0",
		"0",
		"0",
		"0",
		"0",
		"0",
	}
	out_str := [12]string{
		"4330397376401421145",
		"14124799381142128323",
		"8742572140681234676",
		"14345658006221440202",
		"15524073338516903644",
		"5091405722150716653",
		"15002163819607624508",
		"2047012902665707362",
		"16106391063450633726",
		"4680844749859802542",
		"15019775476387350140",
		"1698615465718385111",
	}

	var in [12]big.Int
	var out [12]big.Int
	for i := 0; i < 12; i++ {
		n := new(big.Int)
		n, _ = n.SetString(in_str[i], 10)
		in[i] = *n
	}
	for i := 0; i < 12; i++ {
		n := new(big.Int)
		n, _ = n.SetString(out_str[i], 10)
		out[i] = *n
	}

	var _in [12]frontend.Variable
	var _out [12]frontend.Variable

	for i := 0; i < 12; i++ {
		_in[i] = in[i]
		_out[i] = out[i]
	}

	myCircuit := PoseidonCircuit{
		In:  _in,
		Out: _out,
	}

	fmt.Println(time.Now(), "compiling...")
	r1cs, err := frontend.Compile(ecc.BN254.ScalarField(), r1cs.NewBuilder, &myCircuit)
	if err != nil {
		fmt.Println(err)
		panic(err)
	}

	assignment := &PoseidonCircuit{
		In:  _in,
		Out: _out,
	}

	witness, _ := frontend.NewWitness(assignment, ecc.BN254.ScalarField())
	publicWitness, err := witness.Public()
	if err != nil {
		panic(err)
	}
	fmt.Println(time.Now(), "groth setup...")
	pk, vk, err := groth16.Setup(r1cs)
	if err != nil {
		panic(err)
	}
	err = test.IsSolved(&myCircuit, assignment, ecc.BN254.ScalarField())
	if err != nil {
		panic(err)
	}

	fmt.Println(time.Now(), "groth prove...")
	proof, err := groth16.Prove(r1cs, pk, witness)
	if err != nil {
		panic(err)
	}
	fmt.Println(time.Now(), "groth verify...")

	err = groth16.Verify(proof, vk, publicWitness)
	if err != nil {
		panic(err)
	}

}