package globals_test

import (
	"runtime/debug"
	"testing"

	"sneak.berlin/go/vaultik/internal/globals"
)

// TestGlobalsNew ensures the globals package initializes correctly
func TestGlobalsNew(t *testing.T) {
	t.Parallel()

	g, err := globals.New()
	if err != nil {
		t.Fatalf("Failed to create Globals: %v", err)
	}

	if g == nil {
		t.Fatal("Globals instance is nil")
	}

	if g.Appname != "vaultik" {
		t.Errorf("Expected Appname to be 'vaultik', got '%s'", g.Appname)
	}

	// Version and Commit will be "dev" and "unknown" by default
	if g.Version == "" {
		t.Error("Version should not be empty")
	}

	if g.Commit == "" {
		t.Error("Commit should not be empty")
	}
}

// TestIsDevVersion covers the boundary that matters: everything
// script/version, a plain docker build and goreleaser's snapshot
// template can emit for an untagged build must be recognised as a
// development build, and a real tag must not be. A plain equality check
// against "dev" used to decide this, which classified every
// commit-stamped dev build as a release.
func TestIsDevVersion(t *testing.T) {
	t.Parallel()

	cases := []struct {
		version string
		want    bool
	}{
		// What an untagged build produces.
		{"dev", true},
		{"dev-b6e4a218a39e", true},
		{"dev-b6e4a218a39e-dirty", true},
		// What `git describe --tags --always --dirty` produces with no
		// tag reachable, and on a commit after a tag.
		{"877eb2f", true},
		{"877eb2f-dirty", true},
		{"v1.0.0-3-g877eb2f", true},
		{"v1.0.0-3-g877eb2f-dirty", true},
		{"1.0.0-rc.1-12-g877eb2f", true},
		// A tagged commit with uncommitted changes is not that tag.
		{"v1.0.0-dirty", true},
		// What Go records for a build without linker flags: a
		// pseudo-version for an untagged commit, "+dirty" for a
		// modified checkout.
		{"v1.0.0-rc3.0.20261111001226-abcdefabcdef", true},
		{"v0.0.0-20261111001226-abcdefabcdef", true},
		{"v1.0.1-0.20261111001226-abcdefabcdef", true},
		{"v1.0.0+dirty", true},
		// What a tagged build produces (goreleaser's .Version strips
		// the leading "v"; script/version keeps it).
		{"1.0.0", false},
		{"0.1.0", false},
		{"1.0.0-rc.1", false},
		{"v1.0.0", false},
		{"v1.0.0-rc3", false},
		// A release must not be mistaken for a dev build just because
		// the string happens to contain "dev".
		{"1.0.0-dev", false},
		{"developer", false},
		// A binary with no version string at all did not get stamped,
		// which is a build failure, not a release. It must never print
		// as one. The Makefile refuses to build when script/version
		// yields nothing; this covers a binary linked some other way.
		{"", true},
		// What script/docker and script/cibuild stamp when the host
		// has no git checkout.
		{"unknown", true},
	}

	for _, tc := range cases {
		if got := globals.IsDevVersion(tc.version); got != tc.want {
			t.Errorf("IsDevVersion(%q) = %v, want %v", tc.version, got, tc.want)
		}
	}
}

// TestDefaultVersionIsDev pins the default: a binary whose linker flags
// and build info name no version must report itself as a development
// build rather than as some default release number.
func TestDefaultVersionIsDev(t *testing.T) {
	t.Parallel()

	if !globals.IsDevVersion(globals.DevVersion) {
		t.Errorf("DevVersion %q is not recognised as a dev version",
			globals.DevVersion)
	}
}

// buildInfo returns build info with the given main module version and,
// when revision is not empty, the commit settings Go records for a
// build from a git checkout.
func buildInfo(version, revision string) *debug.BuildInfo {
	info := &debug.BuildInfo{
		Main: debug.Module{Path: "sneak.berlin/go/vaultik", Version: version},
	}

	if revision != "" {
		info.Settings = []debug.BuildSetting{
			{Key: "vcs.revision", Value: revision},
			{Key: "vcs.time", Value: "2026-11-10T23:12:26Z"},
		}
	}

	return info
}

// TestFromBuildInfo covers a binary from `go install` of a tag, which
// carries no linker flags: it must report the tag. Values the linker
// flags set are kept.
func TestFromBuildInfo(t *testing.T) {
	t.Parallel()

	const (
		tag = "v1.0.0-rc3"
		rev = "0123456789abcdef0123456789abcdef01234567"
	)

	cases := []struct {
		name                    string
		info                    *debug.BuildInfo
		version, commit, date   string
		wantVersion, wantCommit string
		wantDate                string
	}{
		{
			name:        "go install of a tag",
			info:        buildInfo(tag, ""),
			version:     globals.DevVersion,
			commit:      globals.Unknown,
			date:        globals.Unknown,
			wantVersion: tag,
			wantCommit:  globals.Unknown,
			wantDate:    globals.Unknown,
		},
		{
			name:        "empty version",
			info:        buildInfo(tag, ""),
			version:     "",
			commit:      globals.Unknown,
			date:        globals.Unknown,
			wantVersion: tag,
			wantCommit:  globals.Unknown,
			wantDate:    globals.Unknown,
		},
		{
			name:        "go build in a git checkout",
			info:        buildInfo(tag, rev),
			version:     globals.DevVersion,
			commit:      globals.Unknown,
			date:        globals.Unknown,
			wantVersion: tag,
			wantCommit:  rev,
			wantDate:    "2026-11-10",
		},
		{
			name:        "Go could not tell the version",
			info:        buildInfo("(devel)", ""),
			version:     globals.DevVersion,
			commit:      globals.Unknown,
			date:        globals.Unknown,
			wantVersion: globals.DevVersion,
			wantCommit:  globals.Unknown,
			wantDate:    globals.Unknown,
		},
		{
			name:        "linker flags set",
			info:        buildInfo(tag, rev),
			version:     "v1.0.0-rc2-4-gabcdef1",
			commit:      "abcdef1",
			date:        "2026-11-01",
			wantVersion: "v1.0.0-rc2-4-gabcdef1",
			wantCommit:  "abcdef1",
			wantDate:    "2026-11-01",
		},
	}

	for _, tc := range cases {
		version, commit, date := globals.FromBuildInfo(
			tc.info, tc.version, tc.commit, tc.date)

		if version != tc.wantVersion || commit != tc.wantCommit ||
			date != tc.wantDate {
			t.Errorf("%s: got %q, %q, %q; want %q, %q, %q", tc.name,
				version, commit, date,
				tc.wantVersion, tc.wantCommit, tc.wantDate)
		}
	}
}