package container

import (
	"context"
	"fmt"
	"log"
	"os"
	"os/exec"
	"path/filepath"
	"sync"
	"syscall"
	"time"

	"git.x2erp.com/qdy/go-svc-code/internal/opencode/config"
	"git.x2erp.com/qdy/go-svc-code/internal/util"
)

// InstanceStatus 实例状态
type InstanceStatus string

const (
	StatusStarting InstanceStatus = "starting"
	StatusRunning  InstanceStatus = "running"
	StatusStopping InstanceStatus = "stopping"
	StatusStopped  InstanceStatus = "stopped"
	StatusError    InstanceStatus = "error"
)

// OpenCodeInstance OpenCode实例
type OpenCodeInstance struct {
	ProjectID  string         `json:"project_id"`
	Port       int            `json:"port"`
	PID        int            `json:"pid"`
	Status     InstanceStatus `json:"status"`
	ConfigPath string         `json:"config_path"`
	WorkDir    string         `json:"work_dir"`
	ToolURL    string         `json:"tool_url"`
	Token      string         `json:"token"`
	TenantID   string         `json:"tenant_id"`
	StartedAt  time.Time      `json:"started_at"`
	StoppedAt  time.Time      `json:"stopped_at,omitempty"`
	Process    *os.Process    `json:"-"`
	Cmd        *exec.Cmd      `json:"-"`
	LogFile    *os.File       `json:"-"`
	Error      string         `json:"error,omitempty"`
}

// InstanceManager 实例管理器
type InstanceManager struct {
	basePort  int                          // 基础端口（svc-code端口）
	basePath  string                       // 项目基础目录
	instances map[string]*OpenCodeInstance // key: projectID
	nextPort  int                          // 下一个可用端口
	mu        sync.RWMutex
	configGen *config.ConfigGenerator
}

// NewInstanceManager 创建实例管理器
func NewInstanceManager(basePort int, basePath, globalConfigPath string) (*InstanceManager, error) {
	// 创建配置生成器
	configGen, err := config.NewConfigGenerator(globalConfigPath)
	if err != nil {
		return nil, fmt.Errorf("创建配置生成器失败: %w", err)
	}

	// 确保基础目录存在
	if err := util.EnsureDirectoryExists(basePath); err != nil {
		return nil, fmt.Errorf("创建基础目录失败: %w", err)
	}

	manager := &InstanceManager{
		basePort:  basePort,
		basePath:  basePath,
		instances: make(map[string]*OpenCodeInstance),
		nextPort:  basePort + 1, // 从基础端口+1开始
		configGen: configGen,
	}

	return manager, nil
}

// StartInstance 启动项目OpenCode实例
func (m *InstanceManager) StartInstance(projectID, tenantID, toolURL, token string) (*OpenCodeInstance, error) {
	m.mu.Lock()
	defer m.mu.Unlock()

	// 检查实例是否已存在
	if instance, exists := m.instances[projectID]; exists {
		if instance.Status == StatusRunning || instance.Status == StatusStarting {
			return instance, fmt.Errorf("项目 %s 的实例已在运行中", projectID)
		}
		// 如果实例存在但已停止，先清理
		delete(m.instances, projectID)
	}

	// 验证项目ID作为目录名的合法性
	if err := util.ValidateProjectDirName(projectID); err != nil {
		return nil, fmt.Errorf("项目ID验证失败: %w", err)
	}

	// 创建项目目录
	projectPath := util.GetProjectPath(m.basePath, projectID)
	if err := util.CreateProjectDirectory(m.basePath, projectID); err != nil {
		return nil, fmt.Errorf("创建项目目录失败: %w", err)
	}

	// 分配端口
	port := m.nextPort
	m.nextPort++ // 简单递增策略

	// 生成配置
	projectConfig := config.ProjectConfig{
		ProjectID: projectID,
		TenantID:  tenantID,
		ToolURL:   toolURL,
		Token:     token,
		Port:      port,
		BasePath:  m.basePath,
	}

	_, err := m.configGen.GenerateAndWrite(projectConfig)
	if err != nil {
		return nil, fmt.Errorf("生成配置失败: %w", err)
	}

	// 创建实例对象
	instance := &OpenCodeInstance{
		ProjectID:  projectID,
		Port:       port,
		Status:     StatusStarting,
		ConfigPath: util.GetOpenCodeConfigPath(m.basePath, projectID),
		WorkDir:    projectPath,
		ToolURL:    toolURL,
		Token:      token,
		TenantID:   tenantID,
		StartedAt:  time.Now(),
	}

	// 启动OpenCode进程
	if err := m.startOpenCodeProcess(instance); err != nil {
		instance.Status = StatusError
		instance.Error = err.Error()
		return instance, fmt.Errorf("启动OpenCode进程失败: %w", err)
	}

	// 保存实例
	m.instances[projectID] = instance

	log.Printf("OpenCode实例启动成功: 项目=%s, 端口=%d, PID=%d", projectID, port, instance.PID)
	return instance, nil
}

// startOpenCodeProcess 启动OpenCode进程
func (m *InstanceManager) startOpenCodeProcess(instance *OpenCodeInstance) error {
	// 构建命令 - opencode serve会自动读取当前目录下的.opencode/opencode.json
	// 使用--port参数指定端口，同时确保配置文件中也有正确的端口
	cmd := exec.Command("opencode", "serve", "--port", fmt.Sprintf("%d", instance.Port))
	cmd.Dir = instance.WorkDir
	cmd.SysProcAttr = &syscall.SysProcAttr{
		Setpgid: true, // 创建进程组，便于管理
	}

	// 设置环境变量
	cmd.Env = append(os.Environ(),
		fmt.Sprintf("OPENCODE_PROJECT_ID=%s", instance.ProjectID),
		fmt.Sprintf("OPENCODE_TENANT_ID=%s", instance.TenantID),
		fmt.Sprintf("OPENCODE_PORT=%d", instance.Port),
		fmt.Sprintf("OPENCODE_TOOL_URL=%s", instance.ToolURL),
	)

	// 创建日志文件
	logsPath := util.GetProjectLogsPath(m.basePath, instance.ProjectID)
	logFile, err := os.Create(filepath.Join(logsPath, fmt.Sprintf("opencode-%s.log", time.Now().Format("20060102-150405"))))
	if err != nil {
		return fmt.Errorf("创建日志文件失败: %w", err)
	}

	// 重定向输出
	cmd.Stdout = logFile
	cmd.Stderr = logFile

	// 启动进程
	if err := cmd.Start(); err != nil {
		logFile.Close()
		return fmt.Errorf("执行命令失败: %w", err)
	}

	// 保存进程信息
	instance.Process = cmd.Process
	instance.Cmd = cmd
	instance.LogFile = logFile
	instance.PID = cmd.Process.Pid
	instance.Status = StatusRunning

	// 启动协程监控进程退出
	go m.monitorProcess(instance)

	return nil
}

// monitorProcess 监控进程状态
func (m *InstanceManager) monitorProcess(instance *OpenCodeInstance) {
	err := instance.Cmd.Wait()

	m.mu.Lock()
	defer m.mu.Unlock()

	// 关闭日志文件
	if instance.LogFile != nil {
		instance.LogFile.Close()
	}

	// 更新实例状态
	if err != nil {
		instance.Status = StatusError
		instance.Error = err.Error()
		log.Printf("OpenCode进程异常退出: 项目=%s, PID=%d, 错误: %v", instance.ProjectID, instance.PID, err)
	} else {
		instance.Status = StatusStopped
		instance.StoppedAt = time.Now()
		log.Printf("OpenCode进程正常退出: 项目=%s, PID=%d", instance.ProjectID, instance.PID)
	}

	// 清理资源
	instance.Process = nil
	instance.Cmd = nil
	instance.LogFile = nil
}

// StopInstance 停止项目OpenCode实例
func (m *InstanceManager) StopInstance(projectID string) error {
	m.mu.Lock()
	defer m.mu.Unlock()

	instance, exists := m.instances[projectID]
	if !exists {
		return fmt.Errorf("项目 %s 的实例不存在", projectID)
	}

	if instance.Status != StatusRunning && instance.Status != StatusStarting {
		return fmt.Errorf("项目 %s 的实例不在运行状态", projectID)
	}

	// 更新状态
	instance.Status = StatusStopping

	// 终止进程组
	if instance.Process != nil {
		// 终止整个进程组
		if err := syscall.Kill(-instance.Process.Pid, syscall.SIGTERM); err != nil {
			log.Printf("发送SIGTERM失败: %v，尝试强制终止", err)
			syscall.Kill(-instance.Process.Pid, syscall.SIGKILL)
		}

		// 等待进程退出
		ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
		defer cancel()

		done := make(chan error, 1)
		go func() {
			_, err := instance.Process.Wait()
			done <- err
		}()

		select {
		case <-ctx.Done():
			log.Printf("进程终止超时，强制杀死: 项目=%s, PID=%d", projectID, instance.PID)
			syscall.Kill(-instance.Process.Pid, syscall.SIGKILL)
		case <-done:
			// 进程已退出
		}
	}

	// 关闭日志文件
	if instance.LogFile != nil {
		instance.LogFile.Close()
		instance.LogFile = nil
	}

	// 更新状态
	instance.Status = StatusStopped
	instance.StoppedAt = time.Now()
	instance.Process = nil
	instance.Cmd = nil

	log.Printf("OpenCode实例已停止: 项目=%s", projectID)
	return nil
}

// GetInstance 获取项目实例
func (m *InstanceManager) GetInstance(projectID string) *OpenCodeInstance {
	m.mu.RLock()
	defer m.mu.RUnlock()

	return m.instances[projectID]
}

// ListInstances 获取所有实例
func (m *InstanceManager) ListInstances() []*OpenCodeInstance {
	m.mu.RLock()
	defer m.mu.RUnlock()

	instances := make([]*OpenCodeInstance, 0, len(m.instances))
	for _, instance := range m.instances {
		instances = append(instances, instance)
	}

	return instances
}

// GetInstanceStatus 获取实例状态
func (m *InstanceManager) GetInstanceStatus(projectID string) (InstanceStatus, error) {
	m.mu.RLock()
	defer m.mu.RUnlock()

	instance, exists := m.instances[projectID]
	if !exists {
		return StatusStopped, fmt.Errorf("项目 %s 的实例不存在", projectID)
	}

	return instance.Status, nil
}

// Cleanup 清理所有实例
func (m *InstanceManager) Cleanup() {
	m.mu.Lock()
	defer m.mu.Unlock()

	for projectID, instance := range m.instances {
		if instance.Status == StatusRunning || instance.Status == StatusStarting {
			log.Printf("清理运行中的实例: 项目=%s", projectID)
			m.stopInstanceInternal(instance)
		}
	}

	m.instances = make(map[string]*OpenCodeInstance)
}

// stopInstanceInternal 内部停止实例方法（无锁）
func (m *InstanceManager) stopInstanceInternal(instance *OpenCodeInstance) {
	if instance.Process != nil {
		syscall.Kill(-instance.Process.Pid, syscall.SIGKILL)
	}

	if instance.LogFile != nil {
		instance.LogFile.Close()
	}

	instance.Status = StatusStopped
	instance.StoppedAt = time.Now()
	instance.Process = nil
	instance.Cmd = nil
	instance.LogFile = nil
}

// GetBasePort 获取基础端口
func (m *InstanceManager) GetBasePort() int {
	return m.basePort
}

// GetBasePath 获取基础路径
func (m *InstanceManager) GetBasePath() string {
	return m.basePath
}

// GetNextPort 获取下一个端口
func (m *InstanceManager) GetNextPort() int {
	m.mu.RLock()
	defer m.mu.RUnlock()
	return m.nextPort
}

// GetInstanceByPort 根据端口获取实例
func (m *InstanceManager) GetInstanceByPort(port int) *OpenCodeInstance {
	m.mu.RLock()
	defer m.mu.RUnlock()

	for _, instance := range m.instances {
		if instance.Port == port {
			return instance
		}
	}

	return nil
}