package releasecheck

import (
	"os"
	"os/exec"
	"path/filepath"
	"strings"
	"testing"
)

func TestReleaseCommandRejectsWrongBranchAndDirtyCheckout(t *testing.T) {
	t.Run("wrong branch", func(t *testing.T) {
		fixture := newReleaseFixture(t)
		fixture.git("checkout", "-qb", "feature")
		fixture.mustFail(t, "release checkout must be on main")
		fixture.requireNoTag(t)
	})
	t.Run("dirty checkout", func(t *testing.T) {
		fixture := newReleaseFixture(t)
		writeReleaseFixtureFile(t, filepath.Join(fixture.worktree, "dirty.txt"), "dirty\n", 0o644)
		fixture.mustFail(t, "release checkout must be clean")
		fixture.requireNoTag(t)
	})
}

func TestReleaseCommandRejectsInvalidInvocation(t *testing.T) {
	fixture := newReleaseFixture(t)
	if output, err := fixture.runWith(); err == nil || !strings.Contains(output, "usage: scripts/release.sh VERSION") {
		t.Fatalf("missing argument error = %v\n%s", err, output)
	}
	if output, err := fixture.runWith("v1.2"); err == nil || !strings.Contains(output, "invalid stable version") {
		t.Fatalf("invalid version error = %v\n%s", err, output)
	}
	fixture.requireNoTag(t)
}

func TestReleaseCommandRejectsUnpublishedOrExistingCandidates(t *testing.T) {
	t.Run("head differs from origin main", func(t *testing.T) {
		fixture := newReleaseFixture(t)
		writeReleaseFixtureFile(t, filepath.Join(fixture.worktree, "local.txt"), "local\n", 0o644)
		fixture.git("add", "local.txt")
		fixture.git("commit", "-qm", "local only")
		fixture.mustFail(t, "HEAD must equal origin/main")
		fixture.requireNoTag(t)
	})
	t.Run("candidate checker fails", func(t *testing.T) {
		fixture := newReleaseFixture(t)
		fixture.extraEnv = append(fixture.extraEnv, "NARRATIO_RELEASE_CHECKER_MODE=fail")
		fixture.mustFail(t, "release candidate validation failed")
		fixture.requireNoTag(t)
	})
	t.Run("local tag exists", func(t *testing.T) {
		fixture := newReleaseFixture(t)
		fixture.git("tag", "v1.2.3")
		fixture.mustFail(t, "local tag already exists")
	})
	t.Run("upstream tag exists", func(t *testing.T) {
		fixture := newReleaseFixture(t)
		fixture.git("tag", "v1.2.3")
		fixture.git("push", "origin", "refs/tags/v1.2.3:refs/tags/v1.2.3")
		fixture.git("tag", "-d", "v1.2.3")
		fixture.mustFail(t, "local tag already exists")
	})
}

func TestReleaseCommandRejectsChangedUpstreamDuringValidation(t *testing.T) {
	fixture := newReleaseFixture(t)
	advance := filepath.Join(t.TempDir(), "advance-origin.sh")
	writeReleaseFixtureFile(t, advance, `#!/bin/sh
set -eu
clone_dir=$(mktemp -d)
trap 'rm -rf "$clone_dir"' 0 HUP INT TERM
git clone -q --branch main "$NARRATIO_RELEASE_TEST_ORIGIN" "$clone_dir"
cd "$clone_dir"
git config user.email releasecheck@example.test
git config user.name 'Release Check'
printf 'advance\n' > upstream.txt
git add upstream.txt
git commit -qm advance
git push -q origin main
`, 0o755)
	fixture.extraEnv = append(fixture.extraEnv,
		"NARRATIO_RELEASE_CHECKER_MODE=advance-origin",
		"NARRATIO_RELEASE_ADVANCE_ORIGIN="+advance,
		"NARRATIO_RELEASE_TEST_ORIGIN="+fixture.origin,
	)
	fixture.mustFail(t, "candidate or origin/main changed during release validation")
	fixture.requireNoTag(t)
}

func TestReleaseCommandPushesOnlyTheRecordedLightweightTag(t *testing.T) {
	fixture := newReleaseFixture(t)
	candidate := fixture.gitOutput("rev-parse", "HEAD^{commit}")
	output, err := fixture.run()
	if err != nil {
		t.Fatalf("release command error = %v\n%s", err, output)
	}
	if !strings.Contains(output, "release: published v1.2.3 at "+candidate) {
		t.Fatalf("release output = %q", output)
	}
	if got := fixture.gitOutput("cat-file", "-t", "refs/tags/v1.2.3"); got != "commit" {
		t.Fatalf("local tag type = %q, want commit", got)
	}
	if got := fixture.gitOutput("rev-parse", "refs/tags/v1.2.3^{commit}"); got != candidate {
		t.Fatalf("local tag commit = %q, want %q", got, candidate)
	}
	if got := fixture.gitOutput("--git-dir", fixture.origin, "show-ref", "--verify", "--hash", "refs/tags/v1.2.3"); got != candidate {
		t.Fatalf("remote tag commit = %q, want %q", got, candidate)
	}
	if got := fixture.gitOutput("--git-dir", fixture.origin, "show-ref", "--verify", "--hash", "refs/heads/main"); got != candidate {
		t.Fatalf("remote main = %q, want %q", got, candidate)
	}
	if got := strings.Fields(fixture.gitOutput("--git-dir", fixture.origin, "for-each-ref", "--format=%(refname)", "refs/heads", "refs/tags")); !slicesEqual(got, []string{"refs/heads/main", "refs/tags/v1.2.3"}) {
		t.Fatalf("remote refs = %#v", got)
	}
}

func TestReleaseCommandKeepsUnpublishedLocalTagAfterPushFailure(t *testing.T) {
	fixture := newReleaseFixture(t)
	writeReleaseFixtureFile(t, filepath.Join(fixture.origin, "hooks", "pre-receive"), "#!/bin/sh\nexit 1\n", 0o755)
	output, err := fixture.run()
	if err == nil || !strings.Contains(output, "local tag v1.2.3 was created but not published") {
		t.Fatalf("push failure = %v\n%s", err, output)
	}
	if got := fixture.gitOutput("cat-file", "-t", "refs/tags/v1.2.3"); got != "commit" {
		t.Fatalf("local tag type after failed push = %q", got)
	}
	if output, err := runReleaseGit(fixture.worktree, "--git-dir", fixture.origin, "show-ref", "--verify", "refs/tags/v1.2.3"); err == nil {
		t.Fatalf("remote tag exists after failed push: %s", output)
	}
}

type releaseFixture struct {
	worktree string
	origin   string
	extraEnv []string
}

func newReleaseFixture(t *testing.T) *releaseFixture {
	t.Helper()
	root := t.TempDir()
	worktree := filepath.Join(root, "worktree")
	origin := filepath.Join(root, "origin.git")
	if err := os.MkdirAll(filepath.Join(worktree, "scripts"), 0o755); err != nil {
		t.Fatal(err)
	}
	if err := os.MkdirAll(filepath.Join(worktree, "docs", "releases"), 0o755); err != nil {
		t.Fatal(err)
	}
	repoRoot := releaseCheckRepoRoot(t)
	copyReleaseFixtureFile(t, filepath.Join(repoRoot, "scripts", "release-lib.sh"), filepath.Join(worktree, "scripts", "release-lib.sh"), 0o755)
	copyReleaseFixtureFile(t, filepath.Join(repoRoot, "scripts", "release.sh"), filepath.Join(worktree, "scripts", "release.sh"), 0o755)
	writeReleaseFixtureFile(t, filepath.Join(worktree, "scripts", "check-release-candidate.sh"), releaseCandidateStub, 0o755)
	writeReleaseFixtureFile(t, filepath.Join(worktree, "docs", "releases", "v1.2.3.md"), "# Narratio v1.2.3\n", 0o644)
	writeReleaseFixtureFile(t, filepath.Join(worktree, "README.md"), "fixture\n", 0o644)

	fixture := &releaseFixture{worktree: worktree, origin: origin}
	fixture.git("init", "-qb", "main")
	fixture.git("config", "user.email", "releasecheck@example.test")
	fixture.git("config", "user.name", "Release Check")
	fixture.git("add", ".")
	fixture.git("commit", "-qm", "fixture")
	if output, err := runReleaseGit(worktree, "init", "--bare", "-q", origin); err != nil {
		t.Fatalf("init bare origin: %v\n%s", err, output)
	}
	fixture.git("remote", "add", "origin", origin)
	fixture.git("push", "-qu", "origin", "main")
	return fixture
}

func (fixture *releaseFixture) run() (string, error) {
	return fixture.runWith("v1.2.3")
}

func (fixture *releaseFixture) runWith(args ...string) (string, error) {
	commandArgs := append([]string{filepath.Join(fixture.worktree, "scripts", "release.sh")}, args...)
	command := exec.Command("sh", commandArgs...)
	command.Dir = fixture.worktree
	command.Env = append(os.Environ(), fixture.extraEnv...)
	output, err := command.CombinedOutput()
	return string(output), err
}

func (fixture *releaseFixture) mustFail(t *testing.T, want string) {
	t.Helper()
	output, err := fixture.run()
	if err == nil || !strings.Contains(output, want) {
		t.Fatalf("release failure = %v\n%s", err, output)
	}
}

func (fixture *releaseFixture) requireNoTag(t *testing.T) {
	t.Helper()
	if fixture.gitOutput("show-ref", "--verify", "refs/tags/v1.2.3") != "" {
		t.Fatal("unexpected local tag")
	}
	if output, err := runReleaseGit(fixture.worktree, "--git-dir", fixture.origin, "show-ref", "--verify", "refs/tags/v1.2.3"); err == nil {
		t.Fatalf("unexpected remote tag: %s", output)
	}
}

func (fixture *releaseFixture) git(args ...string) {
	if output, err := runReleaseGit(fixture.worktree, args...); err != nil {
		panic("fixture git command failed: " + output)
	}
}

func (fixture *releaseFixture) gitOutput(args ...string) string {
	output, err := runReleaseGit(fixture.worktree, args...)
	if err != nil {
		return ""
	}
	return strings.TrimSpace(output)
}

func runReleaseGit(dir string, args ...string) (string, error) {
	command := exec.Command("git", args...)
	command.Dir = dir
	output, err := command.CombinedOutput()
	return string(output), err
}

func copyReleaseFixtureFile(t *testing.T, source, destination string, mode os.FileMode) {
	t.Helper()
	data, err := os.ReadFile(source)
	if err != nil {
		t.Fatal(err)
	}
	writeReleaseFixtureFile(t, destination, string(data), mode)
}

func writeReleaseFixtureFile(t *testing.T, path, contents string, mode os.FileMode) {
	t.Helper()
	if err := os.WriteFile(path, []byte(contents), mode); err != nil {
		t.Fatal(err)
	}
}

const releaseCandidateStub = `#!/bin/sh
set -eu

case "${NARRATIO_RELEASE_CHECKER_MODE:-success}" in
  success) ;;
  fail) exit 1 ;;
  advance-origin) "$NARRATIO_RELEASE_ADVANCE_ORIGIN" ;;
  *) exit 1 ;;
esac
`