import { plainToClass } from 'class-transformer';
import { IsEnum, IsIn, IsNotEmpty, IsNumber, IsString, Max, Min, validateSync } from 'class-validator';
import { BOOLEAN_STRING_VALUES } from '../consts/booleanStringValues';
import type { BooleanStringValue } from '../types/BooleanStringValue';
import { NodeEnv } from '../types/NodeEnv';

class EnvironmentVariables {
    @IsNotEmpty()
    @IsEnum(NodeEnv)
    NODE_ENV: NodeEnv;

    @IsNotEmpty()
    @IsNumber()
    @Min(1)
    @Max(65535)
    BACKEND_PORT: number;

    @IsNotEmpty()
    @IsString()
    POSTGRES_USER: string;

    @IsNotEmpty()
    @IsString()
    POSTGRES_PASSWORD: string;

    @IsNotEmpty()
    @IsString()
    POSTGRES_DB: string;

    @IsNotEmpty()
    @IsString()
    POSTGRES_HOST: string;

    @IsNotEmpty()
    @IsNumber()
    @Min(1)
    @Max(65535)
    POSTGRES_PORT: number;

    @IsNotEmpty()
    @IsIn(BOOLEAN_STRING_VALUES)
    POSTGRES_MIGRATIONS_RUN: BooleanStringValue;

    @IsNotEmpty()
    @IsString()
    CORS_ORIGINS: string;

    @IsNotEmpty()
    @IsIn(BOOLEAN_STRING_VALUES)
    ALTCHA_ENABLED: BooleanStringValue;

    @IsNotEmpty()
    @IsString()
    ALTCHA_HMAC_KEY: string;

    @IsNotEmpty()
    @IsNumber()
    @Min(1)
    @Max(1_000_000)
    ALTCHA_MAX_NUMBER: number;

    @IsNotEmpty()
    @IsNumber()
    @Min(60_000)
    @Max(3_600_000)
    ALTCHA_CHALLENGE_TTL_MS: number;

    @IsNotEmpty()
    @IsNumber()
    @Min(1000)
    @Max(3_600_000)
    THROTTLE_TTL_MS: number;

    @IsNotEmpty()
    @IsNumber()
    @Min(1)
    @Max(1_000_000)
    THROTTLE_LIMIT: number;

    @IsNotEmpty()
    @IsNumber()
    @Min(1000)
    @Max(3_600_000)
    THROTTLE_UPLOAD_TTL_MS: number;

    @IsNotEmpty()
    @IsNumber()
    @Min(1)
    @Max(10_000)
    THROTTLE_UPLOAD_LIMIT: number;

    @IsNotEmpty()
    @IsNumber()
    @Min(1)
    @Max(10_000_000)
    VALIDATION_UPLOAD_MAX_VIEWS_MAX: number;

    @IsNotEmpty()
    @IsNumber()
    @Min(1)
    @Max(50 * 1024 * 1024) // 50MB
    VALIDATION_UPLOAD_MAX_IMAGE_BYTES: number;

    @IsNotEmpty()
    @IsNumber()
    @Min(256 * 1024) // 256KiB
    @Max(16 * 1024 * 1024) // 16MB
    VALIDATION_UPLOAD_JSON_BODY_PADDING_BYTES: number;
}

export const validate = (config: Record<string, unknown>) => {
    const validatedConfig = plainToClass(EnvironmentVariables, config, {
        enableImplicitConversion: true
    });

    const errors = validateSync(validatedConfig, {
        skipMissingProperties: false
    });

    if (errors.length > 0) {
        throw new Error(errors.toString());
    }

    return validatedConfig;
};