import { config as loadDotenv } from "dotenv";
import { z } from "zod";

loadDotenv();

const emptyToUndefined = z.preprocess((value) => {
  if (typeof value !== "string") {
    return value;
  }
  const trimmed = value.trim();
  return trimmed.length === 0 ? undefined : trimmed;
}, z.string().min(1).optional());

const envSchema = z.object({
  DISCORD_BOT_TOKEN: emptyToUndefined,
  DISCORD_APPLICATION_ID: emptyToUndefined,
  DISCORD_COMMAND_GUILD_ID: emptyToUndefined,
  OLLAMA_BASE_URL: z.string().min(1).default("http://localhost:11434"),
  OLLAMA_MODEL: z.string().min(1).default("qwen3:0.6b"),
  OLLAMA_KEEP_ALIVE: z.string().min(1).default("5m"),
  OLLAMA_NUM_CTX: z.coerce.number().int().min(512).max(32768).default(4096),
  LOCAL_AI_VENV_PATH: z.string().min(1).default(".local-ai/.venv"),
  LOCAL_AI_CACHE_DIR: z.string().min(1).default(".local-ai/cache"),
  LOCAL_AI_PYTHON: emptyToUndefined,
  LOCAL_STT_MODEL: z.string().min(1).default("tiny"),
  LOCAL_STT_DEVICE: z.string().min(1).default("auto"),
  LOCAL_STT_COMPUTE_TYPE: z.string().min(1).default("auto"),
  LOCAL_STT_BEAM_SIZE: z.coerce.number().int().min(1).max(8).default(1),
  LOCAL_TTS_LANGUAGE: z.string().min(1).default("KR"),
  LOCAL_TTS_SPEAKER: z.string().min(1).default("KR"),
  LOCAL_TTS_DEVICE: z.string().min(1).default("auto"),
  LOCAL_TTS_SPEED: z.coerce.number().min(0.8).max(1.6).default(1.12),
  BOT_DEFAULT_LANGUAGE: z.string().min(2).default("ko"),
  MAX_CONVERSATION_TURNS: z.coerce.number().int().min(4).max(30).default(12),
  LOCAL_AUDIO_SOURCE: emptyToUndefined,
  LOCAL_AUDIO_SINK: emptyToUndefined,
  LOCAL_SPEAKER_NAME: z.string().min(1).default("local-user"),
  DEBUG_TEXT_EVENTS: z
    .string()
    .optional()
    .transform((value) => value === "true"),
  LOG_LEVEL: z.enum(["debug", "info", "warn", "error"]).default("info"),
});

export type AppConfig = z.infer<typeof envSchema>;
export type AssistantRuntimeConfig = AppConfig;
export type DiscordRuntimeConfig = AssistantRuntimeConfig & {
  DISCORD_BOT_TOKEN: string;
  DISCORD_APPLICATION_ID: string;
};

export function loadConfig(): AppConfig {
  return envSchema.parse(process.env);
}

function requirePresent(value: string | undefined, name: string): string {
  if (!value) {
    throw new Error(`${name} 환경변수가 필요합니다.`);
  }
  return value;
}

export function requireAssistantRuntimeConfig(config: AppConfig): AssistantRuntimeConfig {
  return config;
}

export function requireDiscordRuntimeConfig(config: AppConfig): DiscordRuntimeConfig {
  const assistant = requireAssistantRuntimeConfig(config);
  return {
    ...assistant,
    DISCORD_BOT_TOKEN: requirePresent(config.DISCORD_BOT_TOKEN, "DISCORD_BOT_TOKEN"),
    DISCORD_APPLICATION_ID: requirePresent(config.DISCORD_APPLICATION_ID, "DISCORD_APPLICATION_ID"),
  };
}