// Copyright (c) 2013, Vastech SA (PTY) LTD. All rights reserved.
// http://github.com/gogo/protobuf
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
//
//     * Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
//     * Redistributions in binary form must reproduce the above
// copyright notice, this list of conditions and the following disclaimer
// in the documentation and/or other materials provided with the
// distribution.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

package union

import (
	"github.com/gogo/protobuf/gogoproto"
	"github.com/gogo/protobuf/plugin/testgen"
	"github.com/gogo/protobuf/protoc-gen-gogo/generator"
)

type test struct {
	*generator.Generator
}

func NewTest(g *generator.Generator) testgen.TestPlugin {
	return &test{g}
}

func (p *test) Generate(imports generator.PluginImports, file *generator.FileDescriptor) bool {
	used := false
	randPkg := imports.NewImport("math/rand")
	timePkg := imports.NewImport("time")
	testingPkg := imports.NewImport("testing")
	for _, message := range file.Messages() {
		if !gogoproto.IsUnion(file.FileDescriptorProto, message.DescriptorProto) ||
			!gogoproto.HasTestGen(file.FileDescriptorProto, message.DescriptorProto) {
			continue
		}
		if message.DescriptorProto.GetOptions().GetMapEntry() {
			continue
		}
		used = true
		ccTypeName := generator.CamelCaseSlice(message.TypeName())

		p.P(`func Test`, ccTypeName, `OnlyOne(t *`, testingPkg.Use(), `.T) {`)
		p.In()
		p.P(`popr := `, randPkg.Use(), `.New(`, randPkg.Use(), `.NewSource(`, timePkg.Use(), `.Now().UnixNano()))`)
		p.P(`p := NewPopulated`, ccTypeName, `(popr, true)`)
		p.P(`v := p.GetValue()`)
		p.P(`msg := &`, ccTypeName, `{}`)
		p.P(`if !msg.SetValue(v) {`)
		p.In()
		p.P(`t.Fatalf("OnlyOne: Could not set Value")`)
		p.Out()
		p.P(`}`)
		p.P(`if !p.Equal(msg) {`)
		p.In()
		p.P(`t.Fatalf("%#v !OnlyOne Equal %#v", msg, p)`)
		p.Out()
		p.P(`}`)
		p.Out()
		p.P(`}`)

	}
	return used
}

func init() {
	testgen.RegisterTestPlugin(NewTest)
}