import {OpenAPIV3} from "openapi-types";
import * as lodash from "lodash";
import {OperationContext} from "./openapi/OpenAPIVisitor";

/**
 * Extract information for n8n node from OpenAPI operation
 */
export interface IOperationParser {
    /**
     * Name of the operation (e.g. "Create User")
     */
    name(operation: OpenAPIV3.OperationObject, context: OperationContext): string

    /**
     * Value of the operation (e.g. "create-user")
     */
    value(operation: OpenAPIV3.OperationObject, context: OperationContext): string

    /**
     * Action of the operation (e.g. "Create User") - will be visible in list of actions
     */
    action(operation: OpenAPIV3.OperationObject, context: OperationContext): string

    /**
     * Description of the operation
     */
    description(operation: OpenAPIV3.OperationObject, context: OperationContext): string

    /**
     * Should skip this operation or not
     */
    shouldSkip(operation: OpenAPIV3.OperationObject, context: OperationContext): boolean;
}

/**
 * Default behaviour for OpenAPI to n8n operation parser
 * It will use operationId as name, value and action and summary as description
 * Skip deprecated operations
 */
export class DefaultOperationParser implements IOperationParser {
    shouldSkip(operation: OpenAPIV3.OperationObject, context: OperationContext): boolean {
        return !!operation.deprecated
    }

    name(operation: OpenAPIV3.OperationObject, context: OperationContext): string {
        if (operation.operationId) {
            return lodash.startCase(operation.operationId)
        }
        return context.method.toUpperCase() + " " + context.pattern
    }

    value(operation: OpenAPIV3.OperationObject, context: OperationContext): string {
        let name = this.name(operation, context)
        // replace all non-alphanumeric characters with '-'
        return name.replace(/[^a-zA-Z0-9 ]/g, '-');
    }

    action(operation: OpenAPIV3.OperationObject, context: OperationContext): string {
        return operation.summary || this.name(operation, context)
    }

    description(operation: OpenAPIV3.OperationObject, context: OperationContext): string {
        return operation.description || operation.summary || '';
    }
}