package config

import (
	"errors"
	"os"
	"strconv"
	"time"
)

type Config struct {
	ProfilePath       string
	TasksWSURL        string
	TasksAPIURL       string
	TasksAgentToken   string
	CoreEndpoint      string
	CoreToken         string
	CoreInsecure      bool
	Model             string
	MetricsListenAddr string
	HealthListenAddr  string
	ShutdownTimeout   time.Duration
	ResponseTimeout   time.Duration
}

func Load() (Config, error) {
	c := Config{
		ProfilePath:       env("AGENT_PROFILE_PATH", "profiles/kaya.yaml"),
		TasksWSURL:        os.Getenv("TASKS_WS_URL"),
		TasksAPIURL:       os.Getenv("TASKS_API_URL"),
		TasksAgentToken:   os.Getenv("TASKS_AGENT_TOKEN"),
		CoreEndpoint:      env("CORE_ENDPOINT", "core:50051"),
		CoreToken:         os.Getenv("CORE_TOKEN"),
		CoreInsecure:      envBool("CORE_INSECURE", false),
		Model:             env("MODEL", "deepseek-v4-flash"),
		MetricsListenAddr: env("METRICS_LISTEN_ADDR", ":9097"),
		HealthListenAddr:  env("HEALTH_LISTEN_ADDR", ":8087"),
		ShutdownTimeout:   envDur("SHUTDOWN_TIMEOUT", 15*time.Second),
		ResponseTimeout:   envDur("RESPONSE_TIMEOUT", 120*time.Second),
	}
	if c.TasksWSURL == "" {
		return c, errors.New("TASKS_WS_URL is required")
	}
	if c.TasksAPIURL == "" {
		return c, errors.New("TASKS_API_URL is required")
	}
	if c.TasksAgentToken == "" {
		return c, errors.New("TASKS_AGENT_TOKEN is required")
	}
	if c.CoreToken == "" {
		return c, errors.New("CORE_TOKEN is required")
	}
	if c.ResponseTimeout <= 0 {
		return c, errors.New("RESPONSE_TIMEOUT must be positive")
	}
	return c, nil
}

func env(k, d string) string {
	if v := os.Getenv(k); v != "" {
		return v
	}
	return d
}

func envBool(k string, d bool) bool {
	if v := os.Getenv(k); v != "" {
		b, _ := strconv.ParseBool(v)
		return b
	}
	return d
}

func envDur(k string, d time.Duration) time.Duration {
	if v := os.Getenv(k); v != "" {
		x, err := time.ParseDuration(v)
		if err == nil {
			return x
		}
	}
	return d
}