package executor

import (
	"context"
	"fmt"
	"io"
	"log/slog"
	"os"
	"os/exec"
	"path/filepath"
	"strings"
	"testing"

	"github.com/thepeterstone/claudomator/internal/storage"
	"github.com/thepeterstone/claudomator/internal/task"
)

func TestContainerRunner_BuildDockerArgs(t *testing.T) {
	runner := &ContainerRunner{
		APIURL:      "http://localhost:8484",
		DropsDir:    "/data/drops",
		SSHAuthSock: "/tmp/ssh.sock",
	}
	workspace := "/tmp/ws"
	taskID := "task-123"

	agentHome := "/tmp/ws/.agent-home"
	args := runner.buildDockerArgs(workspace, agentHome, taskID)

	expected := []string{
		"run", "--rm",
		"--add-host=host.docker.internal:host-gateway",
		fmt.Sprintf("--user=%d:%d", os.Getuid(), os.Getgid()),
		"-v", "/tmp/ws:/workspace",
		"-v", "/tmp/ws/.agent-home:/home/agent",
		"-w", "/workspace",
		"--env-file", "/tmp/ws/.claudomator-env",
		"-e", "HOME=/home/agent",
		"-e", "CLAUDOMATOR_API_URL=http://host.docker.internal:8484",
		"-e", "CLAUDOMATOR_TASK_ID=task-123",
		"-e", "CLAUDOMATOR_DROP_DIR=/data/drops",
		"-v", "/tmp/ssh.sock:/tmp/ssh-auth.sock",
		"-e", "SSH_AUTH_SOCK=/tmp/ssh-auth.sock",
	}

	if len(args) != len(expected) {
		t.Fatalf("expected %d args, got %d. Got: %v", len(expected), len(args), args)
	}
	for i, v := range args {
		if v != expected[i] {
			t.Errorf("arg %d: expected %q, got %q", i, expected[i], v)
		}
	}
}

func TestContainerRunner_BuildInnerCmd(t *testing.T) {
	runner := &ContainerRunner{}
	
	t.Run("claude-fresh", func(t *testing.T) {
		tk := &task.Task{Agent: task.AgentConfig{Type: "claude"}}
		exec := &storage.Execution{}
		cmd := runner.buildInnerCmd(tk, exec, false)
		
		cmdStr := strings.Join(cmd, " ")
		if strings.Contains(cmdStr, "--resume") {
			t.Errorf("unexpected --resume flag in fresh run: %q", cmdStr)
		}
		if !strings.Contains(cmdStr, "INST=$(cat /workspace/.claudomator-instructions.txt); claude -p \"$INST\"") {
			t.Errorf("expected cat instructions in sh command, got %q", cmdStr)
		}
	})

	t.Run("claude-resume", func(t *testing.T) {
		tk := &task.Task{Agent: task.AgentConfig{Type: "claude"}}
		exec := &storage.Execution{ResumeSessionID: "orig-session-123"}
		cmd := runner.buildInnerCmd(tk, exec, true)
		
		cmdStr := strings.Join(cmd, " ")
		if !strings.Contains(cmdStr, "--resume orig-session-123") {
			t.Errorf("expected --resume flag with correct session ID, got %q", cmdStr)
		}
	})

	t.Run("gemini", func(t *testing.T) {
		tk := &task.Task{Agent: task.AgentConfig{Type: "gemini"}}
		exec := &storage.Execution{}
		cmd := runner.buildInnerCmd(tk, exec, false)

		cmdStr := strings.Join(cmd, " ")
		if !strings.Contains(cmdStr, "gemini -p \"$INST\"") {
			t.Errorf("expected gemini command with safer quoting, got %q", cmdStr)
		}
	})

	t.Run("custom-binaries", func(t *testing.T) {
		runnerCustom := &ContainerRunner{
			ClaudeBinary: "/usr/bin/claude-v2",
			GeminiBinary: "/usr/local/bin/gemini-pro",
		}
		
		tkClaude := &task.Task{Agent: task.AgentConfig{Type: "claude"}}
		cmdClaude := runnerCustom.buildInnerCmd(tkClaude, &storage.Execution{}, false)
		if !strings.Contains(strings.Join(cmdClaude, " "), "/usr/bin/claude-v2 -p") {
			t.Errorf("expected custom claude binary, got %q", cmdClaude)
		}

		tkGemini := &task.Task{Agent: task.AgentConfig{Type: "gemini"}}
		cmdGemini := runnerCustom.buildInnerCmd(tkGemini, &storage.Execution{}, false)
		if !strings.Contains(strings.Join(cmdGemini, " "), "/usr/local/bin/gemini-pro -p") {
			t.Errorf("expected custom gemini binary, got %q", cmdGemini)
		}
	})
}

func TestContainerRunner_Run_PreservesWorkspaceOnFailure(t *testing.T) {
	logger := slog.New(slog.NewTextHandler(io.Discard, nil))
	runner := &ContainerRunner{
		Logger: logger,
		Image:  "busybox",
		Command: func(ctx context.Context, name string, arg ...string) *exec.Cmd {
			// Mock docker run to exit 1
			if name == "docker" {
				return exec.Command("sh", "-c", "exit 1")
			}
			// Mock git clone to succeed and create the directory
			if name == "git" && len(arg) > 0 && arg[0] == "clone" {
				dir := arg[len(arg)-1]
				os.MkdirAll(dir, 0755)
				return exec.Command("true")
			}
			return exec.Command("true")
		},
	}

	tk := &task.Task{
		ID:            "test-task",
		RepositoryURL: "https://github.com/example/repo.git",
		Agent:         task.AgentConfig{Type: "claude"},
	}
	exec := &storage.Execution{ID: "test-exec", TaskID: "test-task"}

	err := runner.Run(context.Background(), tk, exec)
	if err == nil {
		t.Fatal("expected error due to mocked docker failure")
	}

	// Verify SandboxDir was set and directory exists.
	if exec.SandboxDir == "" {
		t.Fatal("expected SandboxDir to be set even on failure")
	}
	if _, statErr := os.Stat(exec.SandboxDir); statErr != nil {
		t.Errorf("expected sandbox directory to be preserved, but stat failed: %v", statErr)
	} else {
		os.RemoveAll(exec.SandboxDir)
	}
}

func TestBlockedError_IncludesSandboxDir(t *testing.T) {
	// This test requires mocking 'docker run' or the whole Run() which is hard.
	// But we can test that returning BlockedError works.
	err := &BlockedError{
		QuestionJSON: `{"text":"?"}`,
		SessionID:    "s1",
		SandboxDir:   "/tmp/s1",
	}
	if !strings.Contains(err.Error(), "task blocked") {
		t.Errorf("wrong error message: %v", err)
	}
}

func TestIsCompletionReport(t *testing.T) {
	tests := []struct {
		name     string
		json     string
		expected bool
	}{
		{
			name:     "real question with options",
			json:     `{"text": "Should I proceed with implementation?", "options": ["Yes", "No"]}`,
			expected: false,
		},
		{
			name:     "real question no options",
			json:     `{"text": "Which approach do you prefer?"}`,
			expected: false,
		},
		{
			name:     "completion report no options no question mark",
			json:     `{"text": "All tests pass. Implementation complete. Summary written to CLAUDOMATOR_SUMMARY_FILE."}`,
			expected: true,
		},
		{
			name:     "completion report with empty options",
			json:     `{"text": "Feature implemented and committed.", "options": []}`,
			expected: true,
		},
		{
			name:     "invalid json treated as not a report",
			json:     `not json`,
			expected: false,
		},
	}
	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			got := isCompletionReport(tt.json)
			if got != tt.expected {
				t.Errorf("isCompletionReport(%q) = %v, want %v", tt.json, got, tt.expected)
			}
		})
	}
}

func TestTailFile_ReturnsLastNLines(t *testing.T) {
	f, err := os.CreateTemp("", "tailfile-*")
	if err != nil {
		t.Fatal(err)
	}
	defer os.Remove(f.Name())
	for i := 1; i <= 30; i++ {
		fmt.Fprintf(f, "line %d\n", i)
	}
	f.Close()

	got := tailFile(f.Name(), 5)
	lines := strings.Split(strings.TrimSpace(got), "\n")
	if len(lines) != 5 {
		t.Fatalf("want 5 lines, got %d: %q", len(lines), got)
	}
	if lines[0] != "line 26" || lines[4] != "line 30" {
		t.Errorf("want lines 26-30, got: %q", got)
	}
}

func TestDetectUncommittedChanges_ModifiedFile(t *testing.T) {
	dir := t.TempDir()
	run := func(args ...string) {
		cmd := exec.Command(args[0], args[1:]...)
		cmd.Dir = dir
		if out, err := cmd.CombinedOutput(); err != nil {
			t.Fatalf("%v: %s", args, out)
		}
	}
	run("git", "init", dir)
	run("git", "config", "user.email", "test@test.com")
	run("git", "config", "user.name", "Test")
	// Create and commit a file
	if err := os.WriteFile(dir+"/main.go", []byte("package main"), 0644); err != nil {
		t.Fatal(err)
	}
	run("git", "add", "main.go")
	run("git", "commit", "-m", "init")
	// Now modify without committing — simulates agent that forgot to commit
	if err := os.WriteFile(dir+"/main.go", []byte("package main\n// changed"), 0644); err != nil {
		t.Fatal(err)
	}
	err := detectUncommittedChanges(dir)
	if err == nil {
		t.Fatal("expected error for modified uncommitted file, got nil")
	}
	if !strings.Contains(err.Error(), "uncommitted") {
		t.Errorf("error should mention uncommitted, got: %v", err)
	}
}

func TestDetectUncommittedChanges_NewUntrackedSourceFile(t *testing.T) {
	dir := t.TempDir()
	run := func(args ...string) {
		cmd := exec.Command(args[0], args[1:]...)
		cmd.Dir = dir
		if out, err := cmd.CombinedOutput(); err != nil {
			t.Fatalf("%v: %s", args, out)
		}
	}
	run("git", "init", dir)
	run("git", "config", "user.email", "test@test.com")
	run("git", "config", "user.name", "Test")
	run("git", "commit", "--allow-empty", "-m", "init")
	// Agent wrote a new file but never committed it
	if err := os.WriteFile(dir+"/newfile.go", []byte("package main"), 0644); err != nil {
		t.Fatal(err)
	}
	err := detectUncommittedChanges(dir)
	if err == nil {
		t.Fatal("expected error for new untracked source file, got nil")
	}
}

func TestDetectUncommittedChanges_ScaffoldFilesIgnored(t *testing.T) {
	dir := t.TempDir()
	run := func(args ...string) {
		cmd := exec.Command(args[0], args[1:]...)
		cmd.Dir = dir
		if out, err := cmd.CombinedOutput(); err != nil {
			t.Fatalf("%v: %s", args, out)
		}
	}
	run("git", "init", dir)
	run("git", "config", "user.email", "test@test.com")
	run("git", "config", "user.name", "Test")
	run("git", "commit", "--allow-empty", "-m", "init")
	// Write only scaffold files that the harness injects — should not trigger error
	_ = os.WriteFile(dir+"/.claudomator-env", []byte("KEY=val"), 0600)
	_ = os.WriteFile(dir+"/.claudomator-instructions.txt", []byte("do stuff"), 0644)
	_ = os.MkdirAll(dir+"/.agent-home/.claude", 0755)
	err := detectUncommittedChanges(dir)
	if err != nil {
		t.Errorf("scaffold files should not trigger uncommitted error, got: %v", err)
	}
}

func TestDetectUncommittedChanges_CleanRepo(t *testing.T) {
	dir := t.TempDir()
	run := func(args ...string) {
		cmd := exec.Command(args[0], args[1:]...)
		cmd.Dir = dir
		if out, err := cmd.CombinedOutput(); err != nil {
			t.Fatalf("%v: %s", args, out)
		}
	}
	run("git", "init", dir)
	run("git", "config", "user.email", "test@test.com")
	run("git", "config", "user.name", "Test")
	if err := os.WriteFile(dir+"/main.go", []byte("package main"), 0644); err != nil {
		t.Fatal(err)
	}
	run("git", "add", "main.go")
	run("git", "commit", "-m", "init")
	// No modifications — should pass
	err := detectUncommittedChanges(dir)
	if err != nil {
		t.Errorf("clean repo should not error, got: %v", err)
	}
}

func TestGitSafe_PrependsSafeDirectory(t *testing.T) {
	got := gitSafe("-C", "/some/path", "status")
	want := []string{"-c", "safe.directory=*", "-C", "/some/path", "status"}
	if len(got) != len(want) {
		t.Fatalf("gitSafe() = %v, want %v", got, want)
	}
	for i := range want {
		if got[i] != want[i] {
			t.Errorf("gitSafe()[%d] = %q, want %q", i, got[i], want[i])
		}
	}
}

func TestContainerRunner_MissingCredentials_FailsFast(t *testing.T) {
	logger := slog.New(slog.NewTextHandler(io.Discard, nil))

	claudeConfigDir := t.TempDir()

	// Set up ClaudeConfigDir with MISSING credentials (so pre-flight fails)
	// Don't create .credentials.json
	// But DO create .claude.json so the test isolates the credentials check
	if err := os.WriteFile(filepath.Join(claudeConfigDir, ".claude.json"), []byte("{}"), 0644); err != nil {
		t.Fatal(err)
	}

	runner := &ContainerRunner{
		Logger:          logger,
		Image:           "busybox",
		ClaudeConfigDir: claudeConfigDir,
		Command: func(ctx context.Context, name string, arg ...string) *exec.Cmd {
			if name == "git" && len(arg) > 0 && arg[0] == "clone" {
				dir := arg[len(arg)-1]
				os.MkdirAll(dir, 0755)
				return exec.Command("true")
			}
			return exec.Command("true")
		},
	}

	tk := &task.Task{
		ID:            "test-missing-creds",
		RepositoryURL: "https://github.com/example/repo.git",
		Agent:         task.AgentConfig{Type: "claude"},
	}
	e := &storage.Execution{ID: "test-exec", TaskID: "test-missing-creds"}

	err := runner.Run(context.Background(), tk, e)
	if err == nil {
		t.Fatal("expected error due to missing credentials, got nil")
	}
	if !strings.Contains(err.Error(), "credentials not found") {
		t.Errorf("expected 'credentials not found' error, got: %v", err)
	}
}

func TestContainerRunner_MissingSettings_FailsFast(t *testing.T) {
	logger := slog.New(slog.NewTextHandler(io.Discard, nil))

	claudeConfigDir := t.TempDir()

	// Only create credentials but NOT .claude.json
	if err := os.WriteFile(filepath.Join(claudeConfigDir, ".credentials.json"), []byte("{}"), 0600); err != nil {
		t.Fatal(err)
	}

	runner := &ContainerRunner{
		Logger:          logger,
		Image:           "busybox",
		ClaudeConfigDir: claudeConfigDir,
		Command: func(ctx context.Context, name string, arg ...string) *exec.Cmd {
			if name == "git" && len(arg) > 0 && arg[0] == "clone" {
				dir := arg[len(arg)-1]
				os.MkdirAll(dir, 0755)
				return exec.Command("true")
			}
			return exec.Command("true")
		},
	}

	tk := &task.Task{
		ID:            "test-missing-settings",
		RepositoryURL: "https://github.com/example/repo.git",
		Agent:         task.AgentConfig{Type: "claude"},
	}
	e := &storage.Execution{ID: "test-exec-2", TaskID: "test-missing-settings"}

	err := runner.Run(context.Background(), tk, e)
	if err == nil {
		t.Fatal("expected error due to missing settings, got nil")
	}
	if !strings.Contains(err.Error(), "claude settings") {
		t.Errorf("expected 'claude settings' error, got: %v", err)
	}
}

func TestIsAuthError_DetectsAllVariants(t *testing.T) {
	tests := []struct {
		msg  string
		want bool
	}{
		{"Not logged in", true},
		{"OAuth token has expired", true},
		{"authentication_error: invalid token", true},
		{"Please run /login to authenticate", true},
		{"container execution failed: exit status 1", false},
		{"git clone failed", false},
		{"", false},
	}
	for _, tt := range tests {
		var err error
		if tt.msg != "" {
			err = fmt.Errorf("%s", tt.msg)
		}
		got := isAuthError(err)
		if got != tt.want {
			t.Errorf("isAuthError(%q) = %v, want %v", tt.msg, got, tt.want)
		}
	}
}

func TestContainerRunner_AuthError_SyncsAndRetries(t *testing.T) {
	logger := slog.New(slog.NewTextHandler(io.Discard, nil))

	// Create a sync script that creates a marker file
	syncDir := t.TempDir()
	syncMarker := filepath.Join(syncDir, "sync-called")
	syncScript := filepath.Join(syncDir, "sync-creds")
	os.WriteFile(syncScript, []byte("#!/bin/sh\ntouch "+syncMarker+"\n"), 0755)

	claudeConfigDir := t.TempDir()
	// Create both credential files in ClaudeConfigDir
	os.WriteFile(filepath.Join(claudeConfigDir, ".credentials.json"), []byte(`{"token":"fresh"}`), 0600)
	os.WriteFile(filepath.Join(claudeConfigDir, ".claude.json"), []byte("{}"), 0644)

	callCount := 0
	runner := &ContainerRunner{
		Logger:            logger,
		Image:             "busybox",
		ClaudeConfigDir:   claudeConfigDir,
		CredentialSyncCmd: syncScript,
		Command: func(ctx context.Context, name string, arg ...string) *exec.Cmd {
			if name == "git" {
				if len(arg) > 0 && arg[0] == "clone" {
					dir := arg[len(arg)-1]
					os.MkdirAll(dir, 0755)
				}
				return exec.Command("true")
			}
			if name == "docker" {
				callCount++
				if callCount == 1 {
					// First docker call fails with auth error
					return exec.Command("sh", "-c", "echo 'Not logged in' >&2; exit 1")
				}
				// Second docker call "succeeds"
				return exec.Command("sh", "-c", "exit 0")
			}
			if name == syncScript {
				return exec.Command("sh", "-c", "touch "+syncMarker)
			}
			return exec.Command("true")
		},
	}

	tk := &task.Task{
		ID:            "auth-retry-test",
		RepositoryURL: "https://github.com/example/repo.git",
		Agent:         task.AgentConfig{Type: "claude", Instructions: "test"},
	}
	e := &storage.Execution{ID: "auth-retry-exec", TaskID: "auth-retry-test"}

	// Run — first attempt will fail with auth error, triggering sync+retry
	runner.Run(context.Background(), tk, e)
	// We don't check error strictly since second run may also fail (git push etc.)
	// What we care about is that docker was called twice and sync was called
	if callCount < 2 {
		t.Errorf("expected docker to be called at least twice (original + retry), got %d", callCount)
	}
	if _, err := os.Stat(syncMarker); os.IsNotExist(err) {
		t.Error("expected sync-credentials to be called, but marker file not found")
	}
}