// Copyright 2016 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/>.

package bind

import "github.com/ethereum/go-ethereum/accounts/abi"

// tmplData is the data structure required to fill the binding template.
type tmplData struct {
	Package   string                   // Name of the package to place the generated file in
	Contracts map[string]*tmplContract // List of contracts to generate into this file
}

// tmplContract contains the data needed to generate an individual contract binding.
type tmplContract struct {
	Type        string                 // Type name of the main contract binding
	InputABI    string                 // JSON ABI used as the input to generate the binding from
	InputBin    string                 // Optional EVM bytecode used to denetare deploy code from
	Constructor abi.Method             // Contract constructor for deploy parametrization
	Calls       map[string]*tmplMethod // Contract calls that only read state data
	Transacts   map[string]*tmplMethod // Contract calls that write state data
}

// tmplMethod is a wrapper around an abi.Method that contains a few preprocessed
// and cached data fields.
type tmplMethod struct {
	Original   abi.Method // Original method as parsed by the abi package
	Normalized abi.Method // Normalized version of the parsed method (capitalized names, non-anonymous args/returns)
	Structured bool       // Whether the returns should be accumulated into a contract
}

// tmplSource is the Go source template use to generate the contract binding
// based on.
const tmplSource = `
// This file is an automatically generated Go binding. Do not modify as any
// change will likely be lost upon the next re-generation!

package {{.Package}}

{{range $contract := .Contracts}}
	// {{.Type}}ABI is the input ABI used to generate the binding from.
	const {{.Type}}ABI = ` + "`" + `{{.InputABI}}` + "`" + `

	{{if .InputBin}}
		// {{.Type}}Bin is the compiled bytecode used for deploying new contracts.
		const {{.Type}}Bin = ` + "`" + `{{.InputBin}}` + "`" + `

		// Deploy{{.Type}} deploys a new Ethereum contract, binding an instance of {{.Type}} to it.
		func Deploy{{.Type}}(auth *bind.TransactOpts, backend bind.ContractBackend {{range .Constructor.Inputs}}, {{.Name}} {{bindtype .Type}}{{end}}) (common.Address, *types.Transaction, *{{.Type}}, error) {
		  parsed, err := abi.JSON(strings.NewReader({{.Type}}ABI))
		  if err != nil {
		    return common.Address{}, nil, nil, err
		  }
		  address, tx, contract, err := bind.DeployContract(auth, parsed, common.FromHex({{.Type}}Bin), backend {{range .Constructor.Inputs}}, {{.Name}}{{end}})
		  if err != nil {
		    return common.Address{}, nil, nil, err
		  }
		  return address, tx, &{{.Type}}{ {{.Type}}Caller: {{.Type}}Caller{contract: contract}, {{.Type}}Transactor: {{.Type}}Transactor{contract: contract} }, nil
		}
	{{end}}

	// {{.Type}} is an auto generated Go binding around an Ethereum contract.
	type {{.Type}} struct {
	  {{.Type}}Caller     // Read-only binding to the contract
	  {{.Type}}Transactor // Write-only binding to the contract
	}

	// {{.Type}}Caller is an auto generated read-only Go binding around an Ethereum contract.
	type {{.Type}}Caller struct {
	  contract *bind.BoundContract // Generic contract wrapper for the low level calls
	}

	// {{.Type}}Transactor is an auto generated write-only Go binding around an Ethereum contract.
	type {{.Type}}Transactor struct {
	  contract *bind.BoundContract // Generic contract wrapper for the low level calls
	}

	// {{.Type}}Session is an auto generated Go binding around an Ethereum contract,
	// with pre-set call and transact options.
	type {{.Type}}Session struct {
	  Contract     *{{.Type}}        // Generic contract binding to set the session for
	  CallOpts     bind.CallOpts     // Call options to use throughout this session
	  TransactOpts bind.TransactOpts // Transaction auth options to use throughout this session
	}

	// {{.Type}}CallerSession is an auto generated read-only Go binding around an Ethereum contract,
	// with pre-set call options.
	type {{.Type}}CallerSession struct {
	  Contract *{{.Type}}Caller // Generic contract caller binding to set the session for
	  CallOpts bind.CallOpts    // Call options to use throughout this session
	}

	// {{.Type}}TransactorSession is an auto generated write-only Go binding around an Ethereum contract,
	// with pre-set transact options.
	type {{.Type}}TransactorSession struct {
	  Contract     *{{.Type}}Transactor // Generic contract transactor binding to set the session for
	  TransactOpts bind.TransactOpts    // Transaction auth options to use throughout this session
	}

	// New{{.Type}} creates a new instance of {{.Type}}, bound to a specific deployed contract.
	func New{{.Type}}(address common.Address, backend bind.ContractBackend) (*{{.Type}}, error) {
	  contract, err := bind{{.Type}}(address, backend.(bind.ContractCaller), backend.(bind.ContractTransactor))
	  if err != nil {
	    return nil, err
	  }
	  return &{{.Type}}{ {{.Type}}Caller: {{.Type}}Caller{contract: contract}, {{.Type}}Transactor: {{.Type}}Transactor{contract: contract} }, nil
	}

	// New{{.Type}}Caller creates a new read-only instance of {{.Type}}, bound to a specific deployed contract.
	func New{{.Type}}Caller(address common.Address, caller bind.ContractCaller) (*{{.Type}}Caller, error) {
	  contract, err := bind{{.Type}}(address, caller, nil)
	  if err != nil {
	    return nil, err
	  }
	  return &{{.Type}}Caller{contract: contract}, nil
	}

	// New{{.Type}}Transactor creates a new write-only instance of {{.Type}}, bound to a specific deployed contract.
	func New{{.Type}}Transactor(address common.Address, transactor bind.ContractTransactor) (*{{.Type}}Transactor, error) {
	  contract, err := bind{{.Type}}(address, nil, transactor)
	  if err != nil {
	    return nil, err
	  }
	  return &{{.Type}}Transactor{contract: contract}, nil
	}

	// bind{{.Type}} binds a generic wrapper to an already deployed contract.
	func bind{{.Type}}(address common.Address, caller bind.ContractCaller, transactor bind.ContractTransactor) (*bind.BoundContract, error) {
	  parsed, err := abi.JSON(strings.NewReader({{.Type}}ABI))
	  if err != nil {
	    return nil, err
	  }
	  return bind.NewBoundContract(address, parsed, caller, transactor), nil
	}

	{{range .Calls}}
		{{if .Structured}}
			// {{$contract.Type}}{{.Normalized.Name}}Result is the result of the {{.Normalized.Name}} invocation.
			type {{$contract.Type}}{{.Normalized.Name}}Result struct {
					{{range .Normalized.Outputs}}{{.Name}} {{bindtype .Type}}
					{{end}}
			}
		{{end}}

		// {{.Normalized.Name}} is a free data retrieval call binding the contract method 0x{{printf "%x" .Original.Id}}.
		//
		// Solidity: {{.Original.String}}
		func (_{{$contract.Type}} *{{$contract.Type}}Caller) {{.Normalized.Name}}(opts *bind.CallOpts {{range .Normalized.Inputs}}, {{.Name}} {{bindtype .Type}} {{end}}) ({{if .Structured}}{{$contract.Type}}{{.Normalized.Name}}Result,{{else}}{{range .Normalized.Outputs}}{{bindtype .Type}},{{end}}{{end}} error) {
			var (
				{{if .Structured}}ret = new({{$contract.Type}}{{.Normalized.Name}}Result){{else}}{{range $i, $_ := .Normalized.Outputs}}ret{{$i}} = new({{bindtype .Type}})
				{{end}}{{end}}
			)
			out := {{if .Structured}}ret{{else}}{{if eq (len .Normalized.Outputs) 1}}ret0{{else}}[]interface{}{
				{{range $i, $_ := .Normalized.Outputs}}ret{{$i}},
				{{end}}
			}{{end}}{{end}}
			err := _{{$contract.Type}}.contract.Call(opts, out, "{{.Original.Name}}" {{range .Normalized.Inputs}}, {{.Name}}{{end}})
			return {{if .Structured}}*ret,{{else}}{{range $i, $_ := .Normalized.Outputs}}*ret{{$i}},{{end}}{{end}} err
		}

		// {{.Normalized.Name}} is a free data retrieval call binding the contract method 0x{{printf "%x" .Original.Id}}.
		//
		// Solidity: {{.Original.String}}
		func (_{{$contract.Type}} *{{$contract.Type}}Session) {{.Normalized.Name}}({{range $i, $_ := .Normalized.Inputs}}{{if ne $i 0}},{{end}} {{.Name}} {{bindtype .Type}} {{end}}) ({{if .Structured}}{{$contract.Type}}{{.Normalized.Name}}Result, {{else}} {{range .Normalized.Outputs}}{{bindtype .Type}},{{end}} {{end}} error) {
		  return _{{$contract.Type}}.Contract.{{.Normalized.Name}}(&_{{$contract.Type}}.CallOpts {{range .Normalized.Inputs}}, {{.Name}}{{end}})
		}

		// {{.Normalized.Name}} is a free data retrieval call binding the contract method 0x{{printf "%x" .Original.Id}}.
		//
		// Solidity: {{.Original.String}}
		func (_{{$contract.Type}} *{{$contract.Type}}CallerSession) {{.Normalized.Name}}({{range $i, $_ := .Normalized.Inputs}}{{if ne $i 0}},{{end}} {{.Name}} {{bindtype .Type}} {{end}}) ({{if .Structured}}{{$contract.Type}}{{.Normalized.Name}}Result, {{else}} {{range .Normalized.Outputs}}{{bindtype .Type}},{{end}} {{end}} error) {
		  return _{{$contract.Type}}.Contract.{{.Normalized.Name}}(&_{{$contract.Type}}.CallOpts {{range .Normalized.Inputs}}, {{.Name}}{{end}})
		}
	{{end}}

	{{range .Transacts}}
		// {{.Normalized.Name}} is a paid mutator transaction binding the contract method 0x{{printf "%x" .Original.Id}}.
		//
		// Solidity: {{.Original.String}}
		func (_{{$contract.Type}} *{{$contract.Type}}Transactor) {{.Normalized.Name}}(opts *bind.TransactOpts {{range .Normalized.Inputs}}, {{.Name}} {{bindtype .Type}} {{end}}) (*types.Transaction, error) {
			return _{{$contract.Type}}.contract.Transact(opts, "{{.Original.Name}}" {{range .Normalized.Inputs}}, {{.Name}}{{end}})
		}

		// {{.Normalized.Name}} is a paid mutator transaction binding the contract method 0x{{printf "%x" .Original.Id}}.
		//
		// Solidity: {{.Original.String}}
		func (_{{$contract.Type}} *{{$contract.Type}}Session) {{.Normalized.Name}}({{range $i, $_ := .Normalized.Inputs}}{{if ne $i 0}},{{end}} {{.Name}} {{bindtype .Type}} {{end}}) (*types.Transaction, error) {
		  return _{{$contract.Type}}.Contract.{{.Normalized.Name}}(&_{{$contract.Type}}.TransactOpts {{range $i, $_ := .Normalized.Inputs}}, {{.Name}}{{end}})
		}

		// {{.Normalized.Name}} is a paid mutator transaction binding the contract method 0x{{printf "%x" .Original.Id}}.
		//
		// Solidity: {{.Original.String}}
		func (_{{$contract.Type}} *{{$contract.Type}}TransactorSession) {{.Normalized.Name}}({{range $i, $_ := .Normalized.Inputs}}{{if ne $i 0}},{{end}} {{.Name}} {{bindtype .Type}} {{end}}) (*types.Transaction, error) {
		  return _{{$contract.Type}}.Contract.{{.Normalized.Name}}(&_{{$contract.Type}}.TransactOpts {{range $i, $_ := .Normalized.Inputs}}, {{.Name}}{{end}})
		}
	{{end}}
{{end}}
`