package git

import (
	"context"
	"errors"
	"os/exec"
	"strings"
	"testing"
	"time"

	"github.com/stretchr/testify/require"
)

func TestDefaultRunner_exec_BinaryNotFound(t *testing.T) {
	t.Parallel()
	r := NewDefaultRunner(Config{Binary: "this-is-not-a-real-binary-xyz"})
	_, _, err := r.exec(context.Background(), "", nil, "--version")
	require.Error(t, err)
	var ge *GitError
	require.True(t, errors.As(err, &ge))
}

func TestDefaultRunner_exec_NonZeroExit(t *testing.T) {
	t.Parallel()
	gitAvailable(t)
	r := newTestRunner(t)
	_, _, err := r.exec(context.Background(), t.TempDir(), nil, "rev-parse", "HEAD")
	require.Error(t, err)
	var ge *GitError
	require.True(t, errors.As(err, &ge))
	require.NotZero(t, ge.ExitCode)
}

func TestDefaultRunner_exec_Timeout(t *testing.T) {
	t.Parallel()
	gitAvailable(t)
	r := newTestRunner(t)
	ctx, cancel := context.WithTimeout(context.Background(), 1*time.Nanosecond)
	defer cancel()
	// 任意命令都会因 ctx 已过期而立刻被 kill
	_, _, err := r.exec(ctx, "", nil, "version")
	require.Error(t, err)
}

func TestIsAuthError(t *testing.T) {
	t.Parallel()
	cases := []struct {
		stderr string
		want   bool
	}{
		{"Authentication failed for https://...", true},
		{"fatal: could not read Username for 'https://...'", true},
		{"Permission denied (publickey).", true},
		{"random other failure", false},
	}
	for _, c := range cases {
		got := IsAuthError(&GitError{Stderr: c.stderr})
		require.Equal(t, c.want, got, "stderr=%q", c.stderr)
	}
}

func TestCredentialEnv_None(t *testing.T) {
	t.Parallel()
	env, cleanup, err := credentialEnv(t.TempDir(), nil)
	require.NoError(t, err)
	require.Nil(t, env)
	cleanup() // 不应 panic
}

func TestCredentialEnv_PAT(t *testing.T) {
	t.Parallel()
	tmp := t.TempDir()
	env, cleanup, err := credentialEnv(tmp, &Credential{Kind: CredentialPAT, Username: "alice", Secret: []byte("tok")})
	require.NoError(t, err)
	defer cleanup()
	joined := strings.Join(env, "\n")
	require.Contains(t, joined, "GIT_ASKPASS=")
	require.Contains(t, joined, "GIT_PAT_USERNAME=alice")
	require.Contains(t, joined, "GIT_PAT_TOKEN=tok")
	require.Contains(t, joined, "GIT_TERMINAL_PROMPT=0")
}

func TestCredentialEnv_SSHKey(t *testing.T) {
	t.Parallel()
	if _, err := exec.LookPath("ssh"); err != nil {
		t.Skip("ssh not available")
	}
	tmp := t.TempDir()
	env, cleanup, err := credentialEnv(tmp, &Credential{
		Kind:   CredentialSSHKey,
		Secret: []byte("-----BEGIN OPENSSH PRIVATE KEY-----\nstub\n-----END OPENSSH PRIVATE KEY-----\n"),
	})
	require.NoError(t, err)
	defer cleanup()
	require.Len(t, env, 1)
	require.True(t, strings.HasPrefix(env[0], "GIT_SSH_COMMAND="))
	require.Contains(t, env[0], "IdentitiesOnly=yes")
	require.Contains(t, env[0], "StrictHostKeyChecking=accept-new")
}