// Copyright (C) 2019 Storj Labs, Inc.
// See LICENSE for copying information.

package testcontext

import (
	"os"
	"os/exec"
	"path"
	"path/filepath"
	"runtime"
	"strconv"
	"testing"

	"storj.io/storj/internal/version"
)

// CLibMath is the standard C math library (see `man math.h`).
var CLibMath = Include{Standard: true, Library: "m"}

// CompileCOptions stores options for compiling C source to an executable.
type CompileCOptions struct {
	Dest     string
	Sources  []string
	Includes []Include
	NoWarn   bool
}

// Compile compiles the specified package and returns the executable name.
func (ctx *Context) Compile(pkg string, preArgs ...string) string {
	ctx.test.Helper()

	var binName string
	if pkg == "" {
		dir, _ := os.Getwd()
		binName = path.Base(dir)
	} else {
		binName = path.Base(pkg)
	}

	exe := ctx.File("build", binName+".exe")

	args := append([]string{"build"}, preArgs...)
	if raceEnabled {
		args = append(args, "-race")
	}
	if drpcEnabled {
		args = append(args, "-tags=drpc,unittest")
	} else {
		args = append(args, "-tag=unittest")
	}
	args = append(args, "-o", exe, pkg)

	cmd := exec.Command("go", args...)
	ctx.test.Log("exec:", cmd.Args)

	out, err := cmd.CombinedOutput()
	if err != nil {
		ctx.test.Error(string(out))
		ctx.test.Fatal(err)
	}

	return exe
}

// CompileWithVersion compiles the specified package with the version variables set
// to the passed version info values and returns the executable name.
func (ctx *Context) CompileWithVersion(pkg string, info version.Info) string {
	ctx.test.Helper()

	ldFlagsX := map[string]string{
		"storj.io/storj/internal/version.buildTimestamp":  strconv.Itoa(int(info.Timestamp.Unix())),
		"storj.io/storj/internal/version.buildCommitHash": info.CommitHash,
		"storj.io/storj/internal/version.buildVersion":    info.Version.String(),
		"storj.io/storj/internal/version.buildRelease":    strconv.FormatBool(info.Release),
	}

	return ctx.CompileWithLDFlagsX(pkg, ldFlagsX)
}

// CompileWithLDFlagsX compiles the specified package with the -ldflags flag set to
// "-s -w [-X <key>=<value>,...]" given the passed map and returns the executable name.
func (ctx *Context) CompileWithLDFlagsX(pkg string, ldFlagsX map[string]string) string {
	ctx.test.Helper()

	var ldFlags = "-s -w"
	for key, value := range ldFlagsX {
		ldFlags += (" -X " + key + "=" + value)
	}

	return ctx.Compile(pkg, "-ldflags", ldFlags)
}

// CompileShared compiles pkg as c-shared.
// TODO: support inclusion from other directories
//  (cgo header paths are currently relative to package root)
func (ctx *Context) CompileShared(t *testing.T, name string, pkg string) Include {
	t.Helper()

	base := ctx.File("build", name)

	args := []string{"build", "-buildmode", "c-shared"}
	if drpcEnabled {
		args = append(args, "-tags=drpc")
	}
	args = append(args, "-o", base+".so", pkg)

	// not using race detector for c-shared
	cmd := exec.Command("go", args...)
	t.Log("exec:", cmd.Args)

	out, err := cmd.CombinedOutput()
	if err != nil {
		t.Error(string(out))
		t.Fatal(err)
	}
	t.Log(string(out))

	return Include{Header: base + ".h", Library: base + ".so"}
}

// CompileC compiles file as with gcc and adds the includes.
func (ctx *Context) CompileC(t *testing.T, opts CompileCOptions) string {
	t.Helper()

	exe := ctx.File("build", opts.Dest+".exe")

	var args = []string{}
	if !opts.NoWarn {
		args = append(args, "-Wall")
	}
	args = append(args, "-ggdb")
	args = append(args, "-o", exe)
	for _, inc := range opts.Includes {
		if inc.Header != "" {
			args = append(args, "-I", filepath.Dir(inc.Header))
		}
		if inc.Library != "" {
			if inc.Standard {
				args = append(args,
					"-l"+inc.Library,
				)
				continue
			}
			if runtime.GOOS == "windows" {
				args = append(args,
					"-L"+filepath.Dir(inc.Library),
					"-l:"+filepath.Base(inc.Library),
				)
			} else {
				args = append(args, inc.Library)
			}
		}
	}
	args = append(args, opts.Sources...)

	cmd := exec.Command("gcc", args...)
	t.Log("exec:", cmd.Args)

	out, err := cmd.CombinedOutput()
	if err != nil {
		t.Error(string(out))
		t.Fatal(err)
	}
	t.Log(string(out))

	return exe
}

// Include defines an includable library for gcc.
type Include struct {
	Header   string
	Library  string
	Standard bool
}