package config

import (
	"os"
	"strconv"
	"strings"
	"time"
)

// Defaults and constants
const (
	AdminSessionCookieName = "linearvoid_admin_session"
	MaxAdminUploadBytes    int64 = 2 * 1024 * 1024 * 1024
	DefaultAdminChunkSize  int64 = 8 * 1024 * 1024
	MaxAdminChunkSize      int64 = 32 * 1024 * 1024
	DefaultRateLimitMax          = 10
	DefaultRateLimitWindow       = 10 * time.Second
	DefaultAdminSessionTTL       = 12 * time.Hour
	DefaultUserSessionTTL        = 30 * 24 * time.Hour
	DefaultChatPort              = "3000"
)

// PlaylistPath returns the playlist file path from env or default.
func PlaylistPath() string {
	p := strings.TrimSpace(os.Getenv("PLAYLIST_PATH"))
	if p == "" {
		return "/app/playlist/playlist.txt"
	}
	return p
}

// MediaDir returns the media directory from env or default.
func MediaDir() string {
	d := strings.TrimSpace(os.Getenv("MEDIA_DIR"))
	if d == "" {
		return "/app/media"
	}
	return d
}

// AdminUsername returns the admin username from env or default.
func AdminUsername() string {
	u := strings.TrimSpace(os.Getenv("ADMIN_USERNAME"))
	if u == "" {
		return "admin"
	}
	return u
}

// AdminPassword returns the admin password from env or default.
func AdminPassword() string {
	p := strings.TrimSpace(os.Getenv("ADMIN_PASSWORD"))
	if p == "" {
		return "admin"
	}
	return p
}

// AdminSessionTTL returns the admin session TTL from env or default.
func AdminSessionTTL() time.Duration {
	raw := strings.TrimSpace(os.Getenv("ADMIN_SESSION_TTL_HOURS"))
	if raw == "" {
		return DefaultAdminSessionTTL
	}
	hours, err := strconv.Atoi(raw)
	if err != nil || hours <= 0 {
		return DefaultAdminSessionTTL
	}
	return time.Duration(hours) * time.Hour
}

// UserSessionTTL returns the user session TTL from env or default (30 days).
func UserSessionTTL() time.Duration {
	raw := strings.TrimSpace(os.Getenv("USER_SESSION_TTL_HOURS"))
	if raw == "" {
		return DefaultUserSessionTTL
	}
	hours, err := strconv.Atoi(raw)
	if err != nil || hours <= 0 {
		return DefaultUserSessionTTL
	}
	return time.Duration(hours) * time.Hour
}

// RateLimitMax returns the chat rate limit max messages per window.
func RateLimitMax() int {
	raw := strings.TrimSpace(os.Getenv("CHAT_RATE_LIMIT_MAX"))
	if raw == "" {
		return DefaultRateLimitMax
	}
	v, err := strconv.Atoi(raw)
	if err != nil || v <= 0 {
		return DefaultRateLimitMax
	}
	return v
}

// RateLimitWindow returns the chat rate limit window duration.
func RateLimitWindow() time.Duration {
	raw := strings.TrimSpace(os.Getenv("CHAT_RATE_LIMIT_WINDOW_S"))
	if raw == "" {
		return DefaultRateLimitWindow
	}
	v, err := strconv.Atoi(raw)
	if err != nil || v <= 0 {
		return DefaultRateLimitWindow
	}
	return time.Duration(v) * time.Second
}

// ChatPort returns the chat service port from env or default.
func ChatPort() string {
	p := strings.TrimSpace(os.Getenv("CHAT_PORT"))
	if p == "" {
		return DefaultChatPort
	}
	return p
}

// RedisAddress returns the Redis address from env or default.
func RedisAddress() string {
	a := strings.TrimSpace(os.Getenv("REDIS_URL"))
	if a == "" {
		return "redis:6379"
	}
	return a
}

// DatabaseURL returns the database URL from env (empty = SQLite default).
func DatabaseURL() string {
	return strings.TrimSpace(os.Getenv("DATABASE_URL"))
}