package gotool

import (
	"context"
	"encoding/json"
	"os"
	"path/filepath"
	"runtime"
	"strings"
	"testing"
)

func TestNativeAndStaticCommandsUseOwnedBaseline(t *testing.T) {
	clearGoSettings(t)
	t.Setenv("GOENV", "off")
	t.Setenv("GOFLAGS", "-run=^$")
	t.Setenv("GOOS", "windows")
	t.Setenv("GOARCH", "arm64")
	t.Setenv("GOAMD64", "v2")
	t.Setenv("GOEXPERIMENT", "loopvar")

	tool, err := New(context.Background(), t.TempDir())
	if err != nil {
		t.Fatal(err)
	}
	if tool.HostTarget() != (Target{OS: runtime.GOOS, Arch: runtime.GOARCH}) {
		t.Fatalf("Go host = %#v, want runtime host %s/%s", tool.HostTarget(), runtime.GOOS, runtime.GOARCH)
	}

	native := readSettings(t, tool, Native, Target{}, "GOENV", "GOOS", "GOARCH", "GOFLAGS", "GOAMD64", "GOEXPERIMENT", "CGO_ENABLED")
	if native["GOENV"] != "" || native["GOOS"] != runtime.GOOS || native["GOARCH"] != runtime.GOARCH {
		t.Fatalf("native environment = %#v", native)
	}
	if native["GOFLAGS"] != "-mod=readonly" || native["GOAMD64"] == "v2" || native["GOEXPERIMENT"] != "" {
		t.Fatalf("native Go settings = %#v", native)
	}
	if native["CGO_ENABLED"] == "" {
		t.Fatalf("native cgo setting was not resolved: %#v", native)
	}

	static := readSettings(t, tool, Static, Target{OS: "linux", Arch: "amd64"}, "GOOS", "GOARCH", "GOFLAGS", "CGO_ENABLED", "GOAMD64", "GOEXPERIMENT")
	if static["GOOS"] != "linux" || static["GOARCH"] != "amd64" || static["CGO_ENABLED"] != "0" {
		t.Fatalf("static environment = %#v", static)
	}
	if static["GOFLAGS"] != "-mod=readonly" || static["GOAMD64"] != "v1" || static["GOEXPERIMENT"] != "" {
		t.Fatalf("static baseline settings = %#v", static)
	}
}

func TestPersistentSettingsPreserveCachesAndNativeCTools(t *testing.T) {
	clearGoSettings(t)
	cache := filepath.Join(t.TempDir(), "configured-cache")
	moduleCache := filepath.Join(t.TempDir(), "configured-module-cache")
	temporary := filepath.Join(t.TempDir(), "configured-temporary")
	if err := os.Mkdir(temporary, 0o700); err != nil {
		t.Fatal(err)
	}
	goEnv := filepath.Join(t.TempDir(), "go-env")
	contents := strings.Join([]string{
		"GOFLAGS=-run=^$",
		"GOOS=windows",
		"GOARCH=arm64",
		"GOAMD64=v2",
		"GOEXPERIMENT=loopvar",
		"GOCACHE=" + cache,
		"GOMODCACHE=" + moduleCache,
		"GOTMPDIR=" + temporary,
		"CGO_ENABLED=1",
		"CC=releasekit-test-cc",
		"CXX=releasekit-test-cxx",
		"CGO_CFLAGS=-O0 -g",
		"PKG_CONFIG=releasekit-test-pkg-config",
	}, "\n") + "\n"
	if err := os.WriteFile(goEnv, []byte(contents), 0o600); err != nil {
		t.Fatal(err)
	}
	t.Setenv("GOENV", goEnv)

	tool, err := New(context.Background(), t.TempDir())
	if err != nil {
		t.Fatal(err)
	}
	if tool.HostTarget() != (Target{OS: runtime.GOOS, Arch: runtime.GOARCH}) {
		t.Fatalf("Go host = %#v, want runtime host %s/%s", tool.HostTarget(), runtime.GOOS, runtime.GOARCH)
	}
	native := readSettings(t, tool, Native, Target{}, "GOENV", "GOOS", "GOARCH", "GOFLAGS", "GOAMD64", "GOEXPERIMENT", "CGO_ENABLED", "CC", "CXX", "CGO_CFLAGS", "GOCACHE", "GOMODCACHE", "GOTMPDIR", "PKG_CONFIG")
	if native["GOENV"] != "" || native["GOOS"] != runtime.GOOS || native["GOARCH"] != runtime.GOARCH {
		t.Fatalf("native environment = %#v", native)
	}
	if native["GOFLAGS"] != "-mod=readonly" || native["GOAMD64"] == "v2" || native["GOEXPERIMENT"] != "" {
		t.Fatalf("persisted overrides were not cleared: %#v", native)
	}
	if native["CGO_ENABLED"] != "1" || native["CC"] != "releasekit-test-cc" || native["CXX"] != "releasekit-test-cxx" || native["CGO_CFLAGS"] != "-O0 -g" || native["PKG_CONFIG"] != "releasekit-test-pkg-config" {
		t.Fatalf("persistent native C settings = %#v", native)
	}
	if native["GOCACHE"] != cache || native["GOMODCACHE"] != moduleCache || native["GOTMPDIR"] != temporary {
		t.Fatalf("persistent cache settings = %#v", native)
	}
	static := readSettings(t, tool, Static, Target{OS: "linux", Arch: "amd64"}, "GOENV", "GOOS", "GOARCH", "GOFLAGS", "CGO_ENABLED", "GOAMD64", "GOEXPERIMENT", "GOCACHE")
	if static["GOENV"] != "" || static["GOOS"] != "linux" || static["GOARCH"] != "amd64" || static["CGO_ENABLED"] != "0" || static["GOAMD64"] != "v1" || static["GOEXPERIMENT"] != "" || static["GOCACHE"] != cache {
		t.Fatalf("persistent static environment = %#v", static)
	}
}

func readSettings(t *testing.T, tool *Tool, mode Mode, target Target, names ...string) map[string]string {
	t.Helper()
	args := append([]string{"env", "-json"}, names...)
	output, err := tool.Run(context.Background(), t.TempDir(), mode, target, nil, args...)
	if err != nil {
		t.Fatal(err)
	}
	var settings map[string]string
	if err := json.Unmarshal(output, &settings); err != nil {
		t.Fatalf("decode Go environment %q: %v", output, err)
	}
	return settings
}

func clearGoSettings(t *testing.T) {
	t.Helper()
	for _, key := range []string{
		"GOENV", "GOFLAGS", "GOWORK", "GOTOOLCHAIN", "GOPROXY", "GONOPROXY", "GOSUMDB",
		"GOOS", "GOARCH", "GOEXPERIMENT", "GOAMD64", "GOARM", "GOARM64", "GO386", "GOMIPS", "GOMIPS64", "GOPPC64", "GORISCV64", "GOWASM",
		"CGO_ENABLED", "CC", "CXX", "CGO_CFLAGS", "CGO_CPPFLAGS", "CGO_CXXFLAGS", "CGO_LDFLAGS", "GOCACHE", "GOCACHEPROG", "GOMODCACHE", "GOPATH", "GOROOT", "GOTMPDIR", "PKG_CONFIG",
	} {
		value, exists := os.LookupEnv(key)
		if err := os.Unsetenv(key); err != nil {
			t.Fatal(err)
		}
		t.Cleanup(func() {
			if exists {
				_ = os.Setenv(key, value)
			} else {
				_ = os.Unsetenv(key)
			}
		})
	}
}