// Copyright (c) 2012-2015 Ugorji Nwoke. All rights reserved.
// Use of this source code is governed by a MIT license found in the LICENSE file.

package codec

// This file sets up the variables used, including testInitFns.
// Each file should add initialization that should be performed
// after flags are parsed.
//
// init is a multi-step process:
//   - setup vars (handled by init functions in each file)
//   - parse flags
//   - setup derived vars (handled by pre-init registered functions - registered in init function)
//   - post init (handled by post-init registered functions - registered in init function)
// This way, no one has to manage carefully control the initialization
// using file names, etc.
//
// Tests which require external dependencies need the -tag=x parameter.
// They should be run as:
//    go test -tags=x -run=. <other parameters ...>
// Benchmarks should also take this parameter, to include the sereal, xdr, etc.
// To run against codecgen, etc, make sure you pass extra parameters.
// Example usage:
//    go test "-tags=x codecgen" -bench=. <other parameters ...>
//
// To fully test everything:
//    go test -tags=x -benchtime=100ms -tv -bg -bi  -brw -bu -v -run=. -bench=.

// Handling flags
// codec_test.go will define a set of global flags for testing, including:
//   - Use Reset
//   - Use IO reader/writer (vs direct bytes)
//   - Set Canonical
//   - Set InternStrings
//   - Use Symbols
//
// This way, we can test them all by running same set of tests with a different
// set of flags.
//
// Following this, all the benchmarks will utilize flags set by codec_test.go
// and will not redefine these "global" flags.

import (
	"bytes"
	"flag"
	"io"
	"sync"
)

// DO NOT REMOVE - replacement line for go-codec-bench import declaration tag //

type testHED struct {
	H Handle
	E *Encoder
	D *Decoder
}

type ioReaderWrapper struct {
	r io.Reader
}

func (x ioReaderWrapper) Read(p []byte) (n int, err error) {
	return x.r.Read(p)
}

type ioWriterWrapper struct {
	w io.Writer
}

func (x ioWriterWrapper) Write(p []byte) (n int, err error) {
	return x.w.Write(p)
}

var (
	// testNoopH    = NoopHandle(8)
	testMsgpackH = &MsgpackHandle{}
	testBincH    = &BincHandle{}
	testSimpleH  = &SimpleHandle{}
	testCborH    = &CborHandle{}
	testJsonH    = &JsonHandle{}

	testHandles     []Handle
	testPreInitFns  []func()
	testPostInitFns []func()

	testOnce sync.Once

	testHEDs []testHED
)

// flag variables used by tests (and bench)
var (
	testDepth int

	testVerbose        bool
	testInitDebug      bool
	testStructToArray  bool
	testCanonical      bool
	testUseReset       bool
	testWriteNoSymbols bool
	testSkipIntf       bool
	testInternStr      bool
	testUseMust        bool
	testCheckCircRef   bool

	testUseIoEncDec  bool
	testUseIoWrapper bool

	testJsonIndent int
	testMaxInitLen int

	testJsonHTMLCharsAsIs bool
	testJsonPreferFloat   bool

	testNumRepeatString int
)

// variables that are not flags, but which can configure the handles
var (
	testEncodeOptions EncodeOptions
	testDecodeOptions DecodeOptions
)

// flag variables used by bench
var (
	benchDoInitBench      bool
	benchVerify           bool
	benchUnscientificRes  bool = false
	benchMapStringKeyOnly bool
	//depth of 0 maps to ~400bytes json-encoded string, 1 maps to ~1400 bytes, etc
	//For depth>1, we likely trigger stack growth for encoders, making benchmarking unreliable.
	benchDepth     int
	benchInitDebug bool
)

func init() {
	testHEDs = make([]testHED, 0, 32)
	testHandles = append(testHandles,
		// testNoopH,
		testMsgpackH, testBincH, testSimpleH,
		testCborH, testJsonH)
	testInitFlags()
	benchInitFlags()
}

func testInitFlags() {
	// delete(testDecOpts.ExtFuncs, timeTyp)
	flag.IntVar(&testDepth, "tsd", 0, "Test Struc Depth")
	flag.BoolVar(&testVerbose, "tv", false, "Test Verbose")
	flag.BoolVar(&testInitDebug, "tg", false, "Test Init Debug")
	flag.BoolVar(&testUseIoEncDec, "ti", false, "Use IO Reader/Writer for Marshal/Unmarshal")
	flag.BoolVar(&testUseIoWrapper, "tiw", false, "Wrap the IO Reader/Writer with a base pass-through reader/writer")
	flag.BoolVar(&testStructToArray, "ts", false, "Set StructToArray option")
	flag.BoolVar(&testWriteNoSymbols, "tn", false, "Set NoSymbols option")
	flag.BoolVar(&testCanonical, "tc", false, "Set Canonical option")
	flag.BoolVar(&testInternStr, "te", false, "Set InternStr option")
	flag.BoolVar(&testSkipIntf, "tf", false, "Skip Interfaces")
	flag.BoolVar(&testUseReset, "tr", false, "Use Reset")
	flag.IntVar(&testJsonIndent, "td", 0, "Use JSON Indent")
	flag.IntVar(&testNumRepeatString, "trs", 10, "Create string variables by repeating a string N times")
	flag.IntVar(&testMaxInitLen, "tx", 0, "Max Init Len")
	flag.BoolVar(&testUseMust, "tm", true, "Use Must(En|De)code")
	flag.BoolVar(&testCheckCircRef, "tl", false, "Use Check Circular Ref")
	flag.BoolVar(&testJsonHTMLCharsAsIs, "tas", false, "Set JSON HTMLCharsAsIs")
	flag.BoolVar(&testJsonPreferFloat, "tjf", false, "Prefer Float in json")
}

func benchInitFlags() {
	flag.BoolVar(&benchMapStringKeyOnly, "bs", false, "Bench use maps with string keys only")
	flag.BoolVar(&benchInitDebug, "bg", false, "Bench Debug")
	flag.IntVar(&benchDepth, "bd", 1, "Bench Depth")
	flag.BoolVar(&benchDoInitBench, "bi", false, "Run Bench Init")
	flag.BoolVar(&benchVerify, "bv", false, "Verify Decoded Value during Benchmark")
	flag.BoolVar(&benchUnscientificRes, "bu", false, "Show Unscientific Results during Benchmark")
}

func testHEDGet(h Handle) *testHED {
	for i := range testHEDs {
		v := &testHEDs[i]
		if v.H == h {
			return v
		}
	}
	testHEDs = append(testHEDs, testHED{h, NewEncoder(nil, h), NewDecoder(nil, h)})
	return &testHEDs[len(testHEDs)-1]
}

func testReinit() {
	testOnce = sync.Once{}
	testHEDs = nil
}

func testInitAll() {
	// only parse it once.
	if !flag.Parsed() {
		flag.Parse()
	}
	for _, f := range testPreInitFns {
		f()
	}
	for _, f := range testPostInitFns {
		f()
	}
}

func testCodecEncode(ts interface{}, bsIn []byte,
	fn func([]byte) *bytes.Buffer, h Handle) (bs []byte, err error) {
	// bs = make([]byte, 0, approxSize)
	var e *Encoder
	var buf *bytes.Buffer
	if testUseReset {
		e = testHEDGet(h).E
	} else {
		e = NewEncoder(nil, h)
	}
	if testUseIoEncDec {
		buf = fn(bsIn)
		if testUseIoWrapper {
			e.Reset(ioWriterWrapper{buf})
		} else {
			e.Reset(buf)
		}
	} else {
		bs = bsIn
		e.ResetBytes(&bs)
	}
	if testUseMust {
		e.MustEncode(ts)
	} else {
		err = e.Encode(ts)
	}
	if testUseIoEncDec {
		bs = buf.Bytes()
	}
	return
}

func testCodecDecode(bs []byte, ts interface{}, h Handle) (err error) {
	var d *Decoder
	// var buf *bytes.Reader
	if testUseReset {
		d = testHEDGet(h).D
	} else {
		d = NewDecoder(nil, h)
	}
	if testUseIoEncDec {
		buf := bytes.NewReader(bs)
		if testUseIoWrapper {
			d.Reset(ioReaderWrapper{buf})
		} else {
			d.Reset(buf)
		}
	} else {
		d.ResetBytes(bs)
	}
	if testUseMust {
		d.MustDecode(ts)
	} else {
		err = d.Decode(ts)
	}
	return
}

// ----- functions below are used only by benchmarks alone

func fnBenchmarkByteBuf(bsIn []byte) (buf *bytes.Buffer) {
	// var buf bytes.Buffer
	// buf.Grow(approxSize)
	buf = bytes.NewBuffer(bsIn)
	buf.Truncate(0)
	return
}

func benchFnCodecEncode(ts interface{}, bsIn []byte, h Handle) (bs []byte, err error) {
	return testCodecEncode(ts, bsIn, fnBenchmarkByteBuf, h)
}

func benchFnCodecDecode(bs []byte, ts interface{}, h Handle) (err error) {
	return testCodecDecode(bs, ts, h)
}