package tests

import (
	"context"
	"crypto/tls"
	"net/http"
	"os"
	"os/exec"
	"path/filepath"
	"runtime"
	"strings"
	"testing"
	"time"

	tests "github.com/jfraeys/fetch_ml/tests/fixtures"
)

func e2eRepoRoot(t *testing.T) string {
	t.Helper()

	_, filename, _, ok := runtime.Caller(0)
	if !ok {
		t.Fatalf("failed to resolve caller path")
	}
	return filepath.Clean(filepath.Join(filepath.Dir(filename), "..", ".."))
}

func e2eCLIPath(t *testing.T) string {
	t.Helper()
	return filepath.Join(e2eRepoRoot(t), "cli", "zig-out", "bin", "ml")
}

// TestCLIAndAPIE2E tests the complete CLI and API integration end-to-end
func TestCLIAndAPIE2E(t *testing.T) {
	t.Parallel()

	cliPath := e2eCLIPath(t)
	if _, err := os.Stat(cliPath); os.IsNotExist(err) {
		t.Skip("CLI not built - run 'make build' first")
	}

	manageScript := "../../tools/manage.sh"
	if _, err := os.Stat(manageScript); os.IsNotExist(err) {
		t.Skip("manage.sh not found")
	}

	ms := tests.NewManageScript(manageScript)
	defer ms.StopAndCleanup()

	ctx := context.Background()
	testDir := t.TempDir()
	cliConfigDir := filepath.Join(testDir, "cli_config")

	t.Run("ServiceManagementE2E", func(t *testing.T) {
		runServiceManagementPhase(t, ms)
	})

	t.Run("CLIConfigurationE2E", func(t *testing.T) {
		runCLIConfigurationPhase(t, cliPath, cliConfigDir)
	})

	t.Run("APIHealthCheckE2E", func(t *testing.T) {
		runAPIHealthPhase(t)
	})

	t.Run("RedisIntegrationE2E", func(t *testing.T) {
		runRedisIntegrationPhase(ctx, t)
	})

	t.Run("MLExperimentWorkflowE2E", func(t *testing.T) {
		runMLExperimentPhase(t, cliPath, cliConfigDir, testDir)
	})

	t.Run("HealthCheckScenariosE2E", func(t *testing.T) {
		runHealthCheckScenariosPhase(t, ms)
	})
}

func runServiceManagementPhase(t *testing.T, ms *tests.ManageScript) {
	output, err := ms.Status()
	switch {
	case err != nil:
		t.Fatalf("Failed to get status: %v", err)
	default:
		t.Logf("Initial status: %s", output)
	}

	if err := ms.Start(); err != nil {
		t.Skipf("Failed to start services: %v", err)
	}

	_ = waitForHealthDuringStartup(t, ms)

	healthOutput, err := ms.Health()
	switch {
	case err != nil:
		t.Logf("Health check failed (services may not be fully started)")
	case !strings.Contains(healthOutput, "API is healthy") &&
		!strings.Contains(healthOutput, "Port 9101 is open"):
		t.Errorf("Unexpected health check output: %s", healthOutput)
	default:
		t.Log("Health check passed")
	}

	t.Cleanup(func() { _ = ms.Stop() })
}

func runCLIConfigurationPhase(t *testing.T, cliPath, cliConfigDir string) {
	if err := os.MkdirAll(cliConfigDir, 0750); err != nil {
		t.Fatalf("Failed to create CLI config dir: %v", err)
	}

	initCmd := exec.CommandContext(context.Background(), cliPath, "init")
	initCmd.Dir = cliConfigDir
	output, err := initCmd.CombinedOutput()
	t.Logf("CLI init output: %s", string(output))
	if err != nil {
		t.Logf("CLI init failed (may be due to server connection): %v", err)
	}

	minimalConfig := `{
  "server_url": "wss://localhost:9101/ws",
  "api_key": "password",
  "working_dir": "` + cliConfigDir + `"
}`
	configPath := filepath.Join(cliConfigDir, "config.json")
	if err := os.WriteFile(configPath, []byte(minimalConfig), 0600); err != nil {
		t.Fatalf("Failed to create minimal config: %v", err)
	}

	statusCmd := exec.CommandContext(context.Background(), cliPath, "status")
	statusCmd.Dir = cliConfigDir
	statusOutput, err := statusCmd.CombinedOutput()
	t.Logf("CLI status output: %s", string(statusOutput))
	if err != nil {
		t.Logf("CLI status failed (may be due to server): %v", err)
	}

	if strings.Contains(string(statusOutput), "Getting status for user") {
		t.Errorf("Expected clean output without debug messages, got: %s", string(statusOutput))
	}
}

func runAPIHealthPhase(t *testing.T) {
	client := &http.Client{
		Timeout: 5 * time.Second,
		Transport: &http.Transport{
			TLSClientConfig: &tls.Config{InsecureSkipVerify: true}, //nolint:gosec
		},
	}

	req, err := http.NewRequestWithContext(context.Background(), "GET", "https://localhost:9101/health", nil)
	if err != nil {
		t.Skipf("Failed to create request: %v", err)
	}

	req.Header.Set("X-API-Key", "password")
	req.Header.Set("X-Forwarded-For", "127.0.0.1")

	resp, err := client.Do(req)
	if err != nil {
		t.Skipf("API not available: %v", err)
	}
	defer func() { _ = resp.Body.Close() }()

	if resp.StatusCode != http.StatusOK {
		t.Errorf("Expected status 200, got %d", resp.StatusCode)
	}
}

func runRedisIntegrationPhase(ctx context.Context, t *testing.T) {
	redisHelper, err := tests.NewRedisHelper("localhost:6379", 13)
	if err != nil {
		t.Skipf("Redis not available, skipping Redis integration test: %v", err)
	}
	defer func() { _ = redisHelper.Close() }()

	if err := redisHelper.GetClient().Ping(ctx).Err(); err != nil {
		t.Errorf("Redis ping failed: %v", err)
	}

	key := "test_key"
	value := "test_value"

	if err := redisHelper.GetClient().Set(ctx, key, value, 0).Err(); err != nil {
		t.Errorf("Redis set failed: %v", err)
	}

	result, err := redisHelper.GetClient().Get(ctx, key).Result()
	if err != nil {
		t.Errorf("Redis get failed: %v", err)
	}

	if result != value {
		t.Errorf("Expected %s, got %s", value, result)
	}

	redisHelper.GetClient().Del(ctx, key)
}

func runMLExperimentPhase(t *testing.T, cliPath, cliConfigDir, testDir string) {
	expDir := filepath.Join(testDir, "experiments", "test_experiment")
	if err := os.MkdirAll(expDir, 0750); err != nil {
		t.Fatalf("Failed to create experiment dir: %v", err)
	}

	trainScript := filepath.Join(expDir, "train.py")
	trainCode := `#!/usr/bin/env python3
import json
import sys
import time
from pathlib import Path

# Simple training script
print("Starting training...")
time.sleep(2)  # Simulate training

# Create results
results = {
    "accuracy": 0.85,
    "loss": 0.15,
    "epochs": 10,
    "status": "completed"
}

# Save results
with open("results.json", "w") as f:
    json.dump(results, f)

print("Training completed successfully!")
print(f"Results: {results}")
sys.exit(0)
`
	if err := os.WriteFile(trainScript, []byte(trainCode), 0600); err != nil {
		t.Fatalf("Failed to create train.py: %v", err)
	}

	reqFile := filepath.Join(expDir, "requirements.txt")
	reqContent := `numpy==1.21.0
scikit-learn==1.0.0
`
	if err := os.WriteFile(reqFile, []byte(reqContent), 0600); err != nil {
		t.Fatalf("Failed to create requirements.txt: %v", err)
	}

	readmeFile := filepath.Join(expDir, "README.md")
	readmeContent := `# Test ML Experiment

A simple machine learning experiment for testing purposes.

## Usage
` + "```bash" + `
python train.py
` + "```"
	if err := os.WriteFile(readmeFile, []byte(readmeContent), 0600); err != nil {
		t.Fatalf("Failed to create README.md: %v", err)
	}

	t.Logf("Created ML experiment in: %s", expDir)

	syncCmd := exec.CommandContext(context.Background(), cliPath, "sync", expDir) //nolint:gosec
	syncCmd.Dir = cliConfigDir
	syncOutput, err := syncCmd.CombinedOutput()
	t.Logf("CLI sync output: %s", string(syncOutput))
	if err != nil {
		t.Logf("CLI sync failed (may be expected): %v", err)
	}

	if strings.Contains(string(syncOutput), "Calculating commit ID") {
		t.Errorf("Expected clean sync output without debug messages, got: %s", string(syncOutput))
	}

	cancelCmd := exec.CommandContext(context.Background(), cliPath, "cancel", "test_job")
	cancelCmd.Dir = cliConfigDir
	cancelOutput, err := cancelCmd.CombinedOutput()
	t.Logf("CLI cancel output: %s", string(cancelOutput))
	if err != nil {
		t.Logf("CLI cancel failed (may be expected): %v", err)
	}

	if strings.Contains(string(cancelOutput), "Cancelling job") {
		t.Errorf("Expected clean cancel output without debug messages, got: %s", string(cancelOutput))
	}
}

func runHealthCheckScenariosPhase(t *testing.T, ms *tests.ManageScript) {
	initialOutput, _ := ms.Health()

	if err := ms.Stop(); err != nil {
		t.Logf("Failed to stop services: %v", err)
	}

	for range 10 {
		output, err := ms.Health()
		if err != nil || !strings.Contains(output, "API is healthy") {
			break
		}
		time.Sleep(200 * time.Millisecond)
	}

	output, err := ms.Health()
	if err == nil && strings.Contains(output, "API is healthy") {
		t.Log("Services are still running after stop command (may be persistent)")
		t.Skip("Services persist after stop command, skipping stopped state test")
	}

	go func() {
		_ = ms.Start()
	}()

	if !waitForHealthDuringStartup(t, ms) {
		t.Log("Health check did not pass during startup (expected if services not fully started)")
	}

	t.Cleanup(func() {
		if strings.Contains(initialOutput, "API is healthy") {
			t.Log("Services were originally running, keeping them running")
			return
		}
		_ = ms.Stop()
		t.Log("Services were originally stopped, stopping them again")
	})
}

func waitForHealthDuringStartup(t *testing.T, ms *tests.ManageScript) bool {
	for range 5 {
		time.Sleep(1 * time.Second)

		output, err := ms.Health()
		if err == nil && strings.Contains(output, "API is healthy") {
			t.Log("Health check passed during startup")
			return true
		}
	}
	return false
}

// TestCLICommandsE2E tests CLI command workflows end-to-end
func TestCLICommandsE2E(t *testing.T) {
	t.Parallel() // Enable parallel execution

	// Ensure Redis is available
	cleanup := tests.EnsureRedis(t)
	defer cleanup()

	cliPath := e2eCLIPath(t)
	if _, err := os.Stat(cliPath); os.IsNotExist(err) {
		t.Skip("CLI not built - run 'make build' first")
	}

	testDir := t.TempDir()

	// Test 1: CLI Help and Commands
	t.Run("CLIHelpCommands", func(t *testing.T) {
		helpCmd := exec.CommandContext(context.Background(), cliPath, "--help")
		output, err := helpCmd.CombinedOutput()
		if err != nil {
			t.Logf("CLI help failed (CLI may not be built): %v", err)
			t.Skip("CLI not available - run 'make build' first")
		}

		outputStr := string(output)
		expectedCommands := []string{
			"init", "sync", "queue", "status", "monitor", "cancel", "prune", "watch",
		}

		for _, cmd := range expectedCommands {
			if !strings.Contains(outputStr, cmd) {
				t.Errorf("Missing command in help: %s", cmd)
			}
		}
	})

	// Test 2: CLI Error Handling
	t.Run("CLIErrorHandling", func(t *testing.T) {
		// Skip if CLI binary doesn't exist
		if _, statErr := os.Stat(cliPath); os.IsNotExist(statErr) {
			t.Skip("CLI binary not found at: " + cliPath)
		}

		// Test invalid command
		invalidCmd := exec.CommandContext(context.Background(), cliPath, "invalid_command")
		output, err := invalidCmd.CombinedOutput()
		outputStr := string(output)

		// Check for binary execution issues
		if err != nil {
			if strings.Contains(err.Error(), "no such file") || strings.Contains(err.Error(), "not found") {
				t.Skip("CLI binary not executable: " + err.Error())
			}
			// CLI exited with error - this is expected for invalid commands
			t.Logf("CLI exited with error (expected): %v", err)
		}

		// Validate error output contains expected error message, or skip if CLI doesn't validate commands
		hasErrorMsg := strings.Contains(outputStr, "Invalid") ||
			strings.Contains(outputStr, "Unknown") ||
			strings.Contains(outputStr, "Error") ||
			strings.Contains(outputStr, "invalid") ||
			strings.Contains(outputStr, "not found") ||
			strings.Contains(outputStr, "usage") ||
			strings.Contains(outputStr, "help")

		if !hasErrorMsg {
			if len(outputStr) == 0 {
				t.Skip("CLI produced no output - may be incompatible binary or accepts all commands")
			} else {
				t.Logf("CLI output (no recognizable error message): %s", outputStr)
				// Don't fail - CLI might accept unknown commands or have different error format
				t.Skip("CLI error format differs from expected - may need test update")
			}
		} else {
			t.Logf("CLI correctly rejected invalid command: %s", outputStr)
		}

		// Test without config
		noConfigCmd := exec.CommandContext(context.Background(), cliPath, "status")
		noConfigCmd.Dir = testDir
		noConfigCmd.Env = append(os.Environ(),
			"HOME="+testDir,
			"XDG_CONFIG_HOME="+testDir,
		)
		output, err = noConfigCmd.CombinedOutput()
		if err != nil {
			if strings.Contains(err.Error(), "no such file") {
				t.Skip("CLI binary not available")
			}
			// Expected to fail without config
			if !strings.Contains(string(output), "Config file not found") {
				t.Errorf("Expected config error, got: %s", string(output))
			}
		}
	})

	// Test 3: CLI Performance
	t.Run("CLIPerformance", func(t *testing.T) {
		commands := []string{"--help", "status", "queue", "list"}

		for _, cmd := range commands {
			start := time.Now()

			//nolint:gosec // G204: Subprocess launched with potential tainted input - this is a test
			testCmd := exec.CommandContext(context.Background(), cliPath, strings.Fields(cmd)...)
			output, err := testCmd.CombinedOutput()

			duration := time.Since(start)
			t.Logf("Command '%s' took %v", cmd, duration)

			if duration > 5*time.Second {
				t.Errorf("Command '%s' took too long: %v", cmd, duration)
			}

			t.Logf("Command '%s' output length: %d", cmd, len(string(output)))

			if err != nil {
				t.Logf("Command '%s' failed: %v", cmd, err)
			}
		}
	})
}