package executor

import (
	"context"
	"os/exec"
	"strings"
	"sync"
	"testing"
	"time"
)

func TestNew(t *testing.T) {
	e := New("test-namespace")
	if e.namespace != "test-namespace" {
		t.Errorf("namespace = %q, want %q", e.namespace, "test-namespace")
	}
}

func TestCommand_Types(t *testing.T) {
	tests := []struct {
		cmdType CommandType
		want    string
	}{
		{CommandTypeClaude, "claude"},
		{CommandTypeShell, "shell"},
		{CommandTypeGit, "git"},
	}

	for _, tt := range tests {
		t.Run(string(tt.cmdType), func(t *testing.T) {
			if string(tt.cmdType) != tt.want {
				t.Errorf("CommandType = %q, want %q", tt.cmdType, tt.want)
			}
		})
	}
}

func TestExecutor_buildArgs(t *testing.T) {
	e := New("apps")

	tests := []struct {
		name     string
		cmd      *Command
		wantArgs []string
		wantErr  bool
	}{
		{
			name: "claude command",
			cmd: &Command{
				ID:      "cmd-1",
				PodName: "claudebox-test",
				Type:    CommandTypeClaude,
				Args:    []string{"Write a hello world"},
			},
			wantArgs: []string{
				"exec", "-n", "apps", "claudebox-test", "--",
				"claude", "Write a hello world",
			},
		},
		{
			name: "shell command",
			cmd: &Command{
				ID:      "cmd-2",
				PodName: "claudebox-test",
				Type:    CommandTypeShell,
				Args:    []string{"ls -la /workspace"},
			},
			wantArgs: []string{
				"exec", "-n", "apps", "claudebox-test", "--",
				"bash", "-c", "ls -la /workspace",
			},
		},
		{
			name: "git command",
			cmd: &Command{
				ID:      "cmd-3",
				PodName: "claudebox-test",
				Type:    CommandTypeGit,
				Args:    []string{"status"},
			},
			wantArgs: []string{
				"exec", "-n", "apps", "claudebox-test", "--",
				"git", "-C", "/workspace", "status",
			},
		},
		{
			name: "git command with multiple args",
			cmd: &Command{
				ID:      "cmd-4",
				PodName: "claudebox-test",
				Type:    CommandTypeGit,
				Args:    []string{"commit", "-m", "test message"},
			},
			wantArgs: []string{
				"exec", "-n", "apps", "claudebox-test", "--",
				"git", "-C", "/workspace", "commit", "-m", "test message",
			},
		},
	}

	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			// We can't directly test buildArgs since it's internal to Exec,
			// but we can verify the command construction by checking what would be built
			var args []string

			switch tt.cmd.Type {
			case CommandTypeClaude:
				args = []string{
					"exec", "-n", e.namespace, tt.cmd.PodName, "--",
					"claude", tt.cmd.Args[0],
				}
			case CommandTypeShell:
				args = []string{
					"exec", "-n", e.namespace, tt.cmd.PodName, "--",
					"bash", "-c", tt.cmd.Args[0],
				}
			case CommandTypeGit:
				args = append([]string{
					"exec", "-n", e.namespace, tt.cmd.PodName, "--",
					"git", "-C", "/workspace",
				}, tt.cmd.Args...)
			}

			if len(args) != len(tt.wantArgs) {
				t.Errorf("args length = %d, want %d", len(args), len(tt.wantArgs))
				return
			}

			for i, arg := range args {
				if arg != tt.wantArgs[i] {
					t.Errorf("args[%d] = %q, want %q", i, arg, tt.wantArgs[i])
				}
			}
		})
	}
}

func TestExecutor_Exec_UnknownType(t *testing.T) {
	e := New("test")

	var output []string
	handler := func(stream, line string) {
		output = append(output, line)
	}

	result := e.Exec(context.Background(), &Command{
		Type: CommandType("unknown"),
	}, handler)

	if result.ExitCode != 1 {
		t.Errorf("ExitCode = %d, want 1", result.ExitCode)
	}

	if result.Error == nil {
		t.Error("Error should not be nil for unknown command type")
	}

	if !strings.Contains(result.Error.Error(), "unknown command type") {
		t.Errorf("Error = %v, want to contain 'unknown command type'", result.Error)
	}
}

func TestExecutor_Exec_ContextCancellation(t *testing.T) {
	// Skip if kubectl is not available
	if _, err := exec.LookPath("kubectl"); err != nil {
		t.Skip("kubectl not available")
	}

	e := New("default")

	ctx, cancel := context.WithCancel(context.Background())

	var wg sync.WaitGroup
	var result Result

	wg.Add(1)
	go func() {
		defer wg.Done()
		result = e.Exec(ctx, &Command{
			ID:      "test-cancel",
			PodName: "nonexistent-pod",
			Type:    CommandTypeShell,
			Args:    []string{"sleep 10"},
		}, func(stream, line string) {})
	}()

	// Cancel immediately
	cancel()

	wg.Wait()

	// The command should either fail due to context cancellation or pod not found
	// Either way it shouldn't hang
	if result.ExitCode == 0 && result.Error == nil {
		t.Error("Expected command to fail due to cancellation or pod not found")
	}
}

func TestExecutor_CheckConnection(t *testing.T) {
	// This test requires kubectl to be configured
	if _, err := exec.LookPath("kubectl"); err != nil {
		t.Skip("kubectl not available")
	}

	e := New("default")
	ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
	defer cancel()

	// CheckConnection will succeed if kubectl is configured, fail otherwise
	// We just verify it doesn't panic
	_ = e.CheckConnection(ctx)
}

func TestExecutor_PodExists(t *testing.T) {
	// Skip if kubectl is not available
	if _, err := exec.LookPath("kubectl"); err != nil {
		t.Skip("kubectl not available")
	}

	e := New("default")
	ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
	defer cancel()

	// Check for a pod that definitely doesn't exist
	exists, err := e.PodExists(ctx, "definitely-nonexistent-pod-12345")

	// Should return false without error (or skip if cluster not available)
	if err != nil {
		t.Skipf("cluster not available: %v", err)
	}

	if exists {
		t.Error("Expected pod to not exist")
	}
}

// TestStreamOutput tests the streamOutput function behavior
func TestStreamOutput(t *testing.T) {
	tests := []struct {
		name   string
		input  string
		want   []string
	}{
		{
			name:  "single line",
			input: "hello world",
			want:  []string{"hello world"},
		},
		{
			name:  "multiple lines",
			input: "line1\nline2\nline3",
			want:  []string{"line1", "line2", "line3"},
		},
		{
			name:  "empty input",
			input: "",
			want:  nil,
		},
		{
			name:  "trailing newline",
			input: "hello\n",
			want:  []string{"hello"},
		},
	}

	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			var got []string
			handler := func(stream, line string) {
				if stream != "stdout" {
					t.Errorf("stream = %q, want %q", stream, "stdout")
				}
				got = append(got, line)
			}

			r := strings.NewReader(tt.input)
			streamOutput(r, "stdout", handler)

			if len(got) != len(tt.want) {
				t.Errorf("got %d lines, want %d", len(got), len(tt.want))
				return
			}

			for i, line := range got {
				if line != tt.want[i] {
					t.Errorf("line[%d] = %q, want %q", i, line, tt.want[i])
				}
			}
		})
	}
}

// TestResult verifies Result struct behavior
func TestResult(t *testing.T) {
	t.Run("successful result", func(t *testing.T) {
		r := Result{
			ExitCode:   0,
			DurationMs: 1500,
			Error:      nil,
		}

		if r.ExitCode != 0 {
			t.Errorf("ExitCode = %d, want 0", r.ExitCode)
		}

		if r.DurationMs != 1500 {
			t.Errorf("DurationMs = %d, want 1500", r.DurationMs)
		}

		if r.Error != nil {
			t.Errorf("Error = %v, want nil", r.Error)
		}
	})

	t.Run("failed result", func(t *testing.T) {
		r := Result{
			ExitCode:   1,
			DurationMs: 500,
			Error:      nil,
		}

		if r.ExitCode != 1 {
			t.Errorf("ExitCode = %d, want 1", r.ExitCode)
		}
	})
}

// TestCommand verifies Command struct
func TestCommand(t *testing.T) {
	now := time.Now()
	cmd := Command{
		ID:        "cmd-123",
		PodName:   "test-pod",
		Type:      CommandTypeClaude,
		Args:      []string{"prompt here"},
		StartedAt: now,
	}

	if cmd.ID != "cmd-123" {
		t.Errorf("ID = %q, want %q", cmd.ID, "cmd-123")
	}

	if cmd.PodName != "test-pod" {
		t.Errorf("PodName = %q, want %q", cmd.PodName, "test-pod")
	}

	if cmd.Type != CommandTypeClaude {
		t.Errorf("Type = %q, want %q", cmd.Type, CommandTypeClaude)
	}

	if len(cmd.Args) != 1 || cmd.Args[0] != "prompt here" {
		t.Errorf("Args = %v, want [\"prompt here\"]", cmd.Args)
	}

	if !cmd.StartedAt.Equal(now) {
		t.Errorf("StartedAt = %v, want %v", cmd.StartedAt, now)
	}
}