package config

import (
	"crypto/rand"
	"encoding/hex"
	"os"
	"path/filepath"

	"gopkg.in/yaml.v3"
)

type Config struct {
	DeviceUUID      string   `yaml:"device_uuid"`
	EdgeID          string   `yaml:"edge_id"`
	CloudURL        string   `yaml:"cloud_url"`
	MqttBroker      string   `yaml:"mqtt_broker"`
	MqttUser        string   `yaml:"mqtt_user"`
	MqttPass        string   `yaml:"mqtt_pass"`
	EdgeToken       string   `yaml:"edge_token"`
	StreamEnabled   bool     `yaml:"stream_enabled"`
	RTSPURLs        []string `yaml:"rtsp_urls"`
	// 新增：自动按需拉流配置
	StreamPullURL  string `yaml:"stream_pull_url"`  // 云端拉流网关地址
	StreamProtocol string `yaml:"stream_protocol"`  // 拉流协议: flv, rtsp, ws_flv
	AutoPull       bool   `yaml:"auto_pull"`        // 是否启用自动按需拉流
	InferSocket     string   `yaml:"infer_socket"`
	InferFPS        int      `yaml:"infer_fps"`
	InferWorkers    int      `yaml:"infer_workers"`
	ConfThreshold   float64  `yaml:"conf_threshold"`
	DedupWindowSec  int      `yaml:"dedup_window_sec"`
	OTAUrl          string   `yaml:"ota_url"`
	Version         string   `yaml:"version"`
	configPath      string   `json:"-"`
}

func Load(path string) *Config {
	cfg := &Config{
		EdgeID:         "edge-unknown",
		CloudURL:       "http://localhost:8004",
		InferSocket:    "/tmp/edge-infer.sock",
		InferFPS:       5,
		InferWorkers:   2,
		ConfThreshold:  0.5,
		DedupWindowSec: 30,
		Version:        "1.0.0",
		configPath:     path,
	}

	cfg.loadUUID()

	if data, err := os.ReadFile(path); err == nil {
		_ = yaml.Unmarshal(data, cfg)
	}

	if cfg.InferWorkers <= 0 {
		cfg.InferWorkers = 1
	}
	if cfg.DedupWindowSec <= 0 {
		cfg.DedupWindowSec = 30
	}
	return cfg
}

func (c *Config) loadUUID() {
	uuidPath := "/opt/tianyan-edge/device.uuid"
	if data, err := os.ReadFile(uuidPath); err == nil {
		c.DeviceUUID = string(data)
	} else {
		b := make([]byte, 16)
		rand.Read(b)
		c.DeviceUUID = hex.EncodeToString(b)
		os.MkdirAll(filepath.Dir(uuidPath), 0755)
		os.WriteFile(uuidPath, []byte(c.DeviceUUID), 0644)
	}
}

func (c *Config) Save() error {
	data, err := yaml.Marshal(c)
	if err != nil {
		return err
	}
	return os.WriteFile(c.configPath, data, 0644)
}

func (c *Config) GetDeviceIdentity() string {
	if c.DeviceUUID != "" {
		return c.DeviceUUID
	}
	return c.EdgeID
}