package config

import (
	"os"
	"path/filepath"
	"time"

	"gopkg.in/yaml.v3"

	"drmdecryption/repo"
)

type Config struct {
	StreamdURL      string   `yaml:"streamd_url"`
	Token           string   `yaml:"token"`
	PollIntervalSec int      `yaml:"poll_interval_sec"`
	DataDir         string   `yaml:"data_dir"`
	Workers         int      `yaml:"workers"`
	MaxAttempts     int      `yaml:"max_attempts"`
	CaptureWaitSec  int      `yaml:"capture_wait_sec"`
	Devices         []string `yaml:"devices"`
	Python          string   `yaml:"python"`
	WVD             string   `yaml:"wvd"` // path to .wvd device file (required for key fetch)
	UserAgent       string   `yaml:"user_agent"`
	AgentID         string   `yaml:"agent_id"`
}

func (c Config) PollInterval() time.Duration {
	if c.PollIntervalSec <= 0 {
		return 30 * time.Second
	}
	return time.Duration(c.PollIntervalSec) * time.Second
}

func (c Config) CaptureWait() time.Duration {
	if c.CaptureWaitSec <= 0 {
		return 180 * time.Second
	}
	return time.Duration(c.CaptureWaitSec) * time.Second
}

func Load(path string) (Config, error) {
	root := repo.Root()
	if path == "" {
		path = filepath.Join(root, "apps", "agent", "agent.yaml")
	}
	var cfg Config
	raw, err := os.ReadFile(path)
	if err != nil {
		if os.IsNotExist(err) {
			cfg = defaults(root)
			return cfg, nil
		}
		return cfg, err
	}
	if err := yaml.Unmarshal(raw, &cfg); err != nil {
		return cfg, err
	}
	cfg = applyDefaults(cfg, root)
	return cfg, nil
}

func defaults(root string) Config {
	return applyDefaults(Config{}, root)
}

func applyDefaults(cfg Config, root string) Config {
	if cfg.StreamdURL == "" {
		cfg.StreamdURL = "http://127.0.0.1:8083"
	}
	if cfg.Token == "" {
		cfg.Token = os.Getenv("STREAMD_TOKEN")
	}
	if cfg.PollIntervalSec <= 0 {
		cfg.PollIntervalSec = 30
	}
	if cfg.DataDir == "" {
		cfg.DataDir = filepath.Join(root, ".cache", "agent")
	} else if !filepath.IsAbs(cfg.DataDir) {
		cfg.DataDir = filepath.Join(root, cfg.DataDir)
	}
	if cfg.Workers <= 0 {
		cfg.Workers = 1
	}
	if cfg.MaxAttempts <= 0 {
		cfg.MaxAttempts = 5
	}
	if cfg.CaptureWaitSec <= 0 {
		cfg.CaptureWaitSec = 180
	}
	if cfg.AgentID == "" {
		// Stable across restarts so the same agent can reclaim after a crash.
		// Override in apps/agent/agent.yaml when running multiple agents.
		host, _ := os.Hostname()
		if host == "" {
			host = "agent"
		}
		cfg.AgentID = host
	}
	if cfg.WVD != "" && !filepath.IsAbs(cfg.WVD) {
		cfg.WVD = filepath.Join(root, cfg.WVD)
	}
	return cfg
}