package config

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

const (
	DefaultMode        = "smoke"
	DefaultPlatformURL = "http://127.0.0.1:8080"
	DefaultEndpointID  = "run-local"
	DefaultDisplayName = "Local Run"
	DefaultVersion     = "0.1.0"
)

type Config struct {
	Mode              string
	PlatformURL       string
	RunEndpointID     string
	DisplayName       string
	Version           string
	RegistrationToken string
	WorkspaceRoot     string
	SpoolRoot         string
	MaxJobs           int
	HeartbeatInterval time.Duration
	PollInterval      time.Duration
	RetryBackoff      time.Duration
}

func Load() Config {
	mode := os.Getenv("RUN_MODE")
	if mode == "" {
		mode = DefaultMode
	}

	platformURL := os.Getenv("RUN_PLATFORM_URL")
	if platformURL == "" {
		platformURL = DefaultPlatformURL
	}

	workspaceRoot := envOrDefault("RUN_WORKSPACE_ROOT", filepath.Join(".", ".run-workspace"))
	return Config{
		Mode:              mode,
		PlatformURL:       platformURL,
		RunEndpointID:     envOrDefault("RUN_ENDPOINT_ID", DefaultEndpointID),
		DisplayName:       envOrDefault("RUN_DISPLAY_NAME", DefaultDisplayName),
		Version:           envOrDefault("RUN_VERSION", DefaultVersion),
		RegistrationToken: envOrDefault("RUN_REGISTRATION_TOKEN", "local-registration"),
		WorkspaceRoot:     workspaceRoot,
		SpoolRoot:         envOrDefault("RUN_SPOOL_ROOT", filepath.Join(workspaceRoot, "spool")),
		MaxJobs:           intEnvOrDefault("RUN_MAX_JOBS", 1),
		HeartbeatInterval: durationEnvOrDefault("RUN_HEARTBEAT_INTERVAL_MS", 15*time.Second),
		PollInterval:      durationEnvOrDefault("RUN_POLL_INTERVAL_MS", 2*time.Second),
		RetryBackoff:      durationEnvOrDefault("RUN_RETRY_BACKOFF_MS", time.Second),
	}
}

func envOrDefault(key string, fallback string) string {
	value := os.Getenv(key)
	if value == "" {
		return fallback
	}
	return value
}

func intEnvOrDefault(key string, fallback int) int {
	value, err := strconv.Atoi(os.Getenv(key))
	if err != nil || value <= 0 {
		return fallback
	}
	return value
}

func durationEnvOrDefault(key string, fallback time.Duration) time.Duration {
	value, err := strconv.Atoi(os.Getenv(key))
	if err != nil || value <= 0 {
		return fallback
	}
	return time.Duration(value) * time.Millisecond
}