import { ConfigurableWorkflowAgent } from './factory';
import { DEFAULT_MULTI_AGENT_WORKFLOW, MultiAgentStageConfig } from '../config';

export class AgentWorkflowManager {
    /**
     * 리팩토링된 고성능 에이전트 엔진을 통해 워크플로우를 실행합니다.
     */
    public static async runStrictWorkflow(
        prompt: string,
        modelName: string,
        brainContext: string,
        signal: AbortSignal,
        onProgress: (step: string, message: string) => void,
        workflow: MultiAgentStageConfig[] = DEFAULT_MULTI_AGENT_WORKFLOW
    ): Promise<string> {
        const stages = workflow.length > 0 ? workflow : DEFAULT_MULTI_AGENT_WORKFLOW;
        const stageOutputs: string[] = [];
        try {
            for (const [index, stage] of stages.entries()) {
                if (signal.aborted) throw new Error('AbortError');

                const agent = new ConfigurableWorkflowAgent(modelName, stage);
                const stepName = stage.name || `Stage ${index + 1}`;
                onProgress(stepName, `Running ${index + 1}/${stages.length}`);

                const stageInput = this.buildStageInput(stage, prompt, stageOutputs);
                const result = await agent.execute(stageInput, brainContext, signal);
                this.validateResult(result, stepName);
                stageOutputs.push(result);

                onProgress(stepName, `Completed ${index + 1}/${stages.length}`);
            }

            return stageOutputs[stageOutputs.length - 1];
        } catch (error: any) {
            if (error.name === 'AbortError' || error.message.includes('cancelled')) {
                throw error;
            }
            throw new Error(`[Workflow Manager] ${error.message}`);
        }
    }

    private static buildStageInput(stage: MultiAgentStageConfig, originalPrompt: string, stageOutputs: string[]): string {
        const previous = stageOutputs[stageOutputs.length - 1] || '';
        if (stage.input === 'original') {
            return originalPrompt;
        }

        if (stage.input === 'previous') {
            return previous || originalPrompt;
        }

        return [
            '## Original User Request',
            originalPrompt,
            '',
            '## Previous Stage Output',
            previous || 'No previous stage output.'
        ].join('\n');
    }

    private static validateResult(data: string, step: string) {
        if (!data || data.trim().length < 10) {
            throw new Error(`${step} agent did not return a usable response.`);
        }
    }
}