package deployment

import (
	"fmt"
	"sync"
	"time"
)

// DeploymentStatus represents deployment status
type DeploymentStatus string

const (
	StatusPending  DeploymentStatus = "pending"
	StatusBuilding DeploymentStatus = "building"
	StatusPushing  DeploymentStatus = "pushing"
	StatusApplying DeploymentStatus = "applying"
	StatusSuccess  DeploymentStatus = "success"
	StatusFailed   DeploymentStatus = "failed"
)

// DeploymentInfo represents a deployment attempt
type DeploymentInfo struct {
	ID        string
	Version   string
	Status    DeploymentStatus
	StartedAt time.Time
	CompletedAt time.Time
	Container string
	Registry  string
	Manifest  string
}

// SelfDeployer handles orchestrator self-deployment
type SelfDeployer struct {
	mu              sync.RWMutex
	deployments     map[string]*DeploymentInfo
	currentVersion  string
	registry        string
	kubeConfig      string
}

// NewSelfDeployer creates a new self deployer
func NewSelfDeployer(registry, kubeConfig string) *SelfDeployer {
	return &SelfDeployer{
		deployments:    make(map[string]*DeploymentInfo),
		currentVersion: "1.0.0",
		registry:       registry,
		kubeConfig:     kubeConfig,
	}
}

// BuildContainer builds a Docker container image
func (sd *SelfDeployer) BuildContainer(version string) (string, error) {
	if version == "" {
		return "", fmt.Errorf("version required")
	}

	sd.mu.Lock()
	defer sd.mu.Unlock()

	deploymentID := fmt.Sprintf("deploy-%s-%d", version, len(sd.deployments))
	
	deployment := &DeploymentInfo{
		ID:        deploymentID,
		Version:   version,
		Status:    StatusBuilding,
		StartedAt: time.Now(),
		Container: fmt.Sprintf("%s/orchestrator:%s", sd.registry, version),
		Registry:  sd.registry,
	}

	sd.deployments[deploymentID] = deployment

	// Simulate build
	deployment.Status = StatusPushing

	return deploymentID, nil
}

// PushImage pushes the container image to registry
func (sd *SelfDeployer) PushImage(deploymentID string) error {
	sd.mu.Lock()
	defer sd.mu.Unlock()

	deployment, exists := sd.deployments[deploymentID]
	if !exists {
		return fmt.Errorf("deployment not found: %s", deploymentID)
	}

	if deployment.Status != StatusPushing {
		return fmt.Errorf("invalid status for push: %s", deployment.Status)
	}

	// Simulate push
	deployment.Status = StatusApplying

	return nil
}

// GenerateManifest generates K8s manifests
func (sd *SelfDeployer) GenerateManifest(deploymentID string, replicas int) (string, error) {
	sd.mu.Lock()
	defer sd.mu.Unlock()

	deployment, exists := sd.deployments[deploymentID]
	if !exists {
		return "", fmt.Errorf("deployment not found: %s", deploymentID)
	}

	manifest := fmt.Sprintf(`
apiVersion: apps/v1
kind: Deployment
metadata:
  name: poimen-orchestrator
spec:
  replicas: %d
  selector:
    matchLabels:
      app: poimen-orchestrator
  template:
    metadata:
      labels:
        app: poimen-orchestrator
    spec:
      containers:
      - name: orchestrator
        image: %s
        ports:
        - containerPort: 7233
        - containerPort: 8081
`, replicas, deployment.Container)

	deployment.Manifest = manifest

	return manifest, nil
}

// Deploy applies the deployment to K8s
func (sd *SelfDeployer) Deploy(deploymentID string) error {
	sd.mu.Lock()
	defer sd.mu.Unlock()

	deployment, exists := sd.deployments[deploymentID]
	if !exists {
		return fmt.Errorf("deployment not found: %s", deploymentID)
	}

	if deployment.Status != StatusApplying {
		return fmt.Errorf("invalid status for deploy: %s", deployment.Status)
	}

	// Simulate deployment
	deployment.Status = StatusSuccess
	deployment.CompletedAt = time.Now()

	// Update current version
	sd.currentVersion = deployment.Version

	return nil
}

// Rollback rolls back to previous version
func (sd *SelfDeployer) Rollback(previousVersion string) error {
	sd.mu.Lock()
	defer sd.mu.Unlock()

	// Create a new deployment for rollback
	deploymentID := fmt.Sprintf("rollback-%s-%d", previousVersion, len(sd.deployments))

	deployment := &DeploymentInfo{
		ID:        deploymentID,
		Version:   previousVersion,
		Status:    StatusSuccess,
		StartedAt: time.Now(),
		CompletedAt: time.Now(),
		Container: fmt.Sprintf("%s/orchestrator:%s", sd.registry, previousVersion),
	}

	sd.deployments[deploymentID] = deployment
	sd.currentVersion = previousVersion

	return nil
}

// GetDeploymentInfo retrieves deployment info
func (sd *SelfDeployer) GetDeploymentInfo(deploymentID string) (*DeploymentInfo, bool) {
	sd.mu.RLock()
	defer sd.mu.RUnlock()

	deployment, exists := sd.deployments[deploymentID]
	return deployment, exists
}

// GetCurrentVersion returns the current orchestrator version
func (sd *SelfDeployer) GetCurrentVersion() string {
	sd.mu.RLock()
	defer sd.mu.RUnlock()

	return sd.currentVersion
}

// ListDeployments returns all deployments
func (sd *SelfDeployer) ListDeployments() map[string]*DeploymentInfo {
	sd.mu.RLock()
	defer sd.mu.RUnlock()

	result := make(map[string]*DeploymentInfo)
	for id, deployment := range sd.deployments {
		result[id] = deployment
	}

	return result
}

// HealthCheck checks if the deployed orchestrator is healthy
func (sd *SelfDeployer) HealthCheck(deploymentID string) (bool, error) {
	sd.mu.RLock()
	defer sd.mu.RUnlock()

	deployment, exists := sd.deployments[deploymentID]
	if !exists {
		return false, fmt.Errorf("deployment not found: %s", deploymentID)
	}

	// Simulate health check
	return deployment.Status == StatusSuccess, nil
}

// SetVersion sets the target version
func (sd *SelfDeployer) SetVersion(version string) {
	sd.mu.Lock()
	defer sd.mu.Unlock()

	sd.currentVersion = version
}