import type {
  AgentInfo,
  AgentInteractionConfig,
  AgentValidationIssue,
} from './types';

export const MAX_WELCOME_MESSAGE_LENGTH = 300;
export const MAX_SUGGESTED_QUESTION_COUNT = 6;
export const MAX_SUGGESTED_QUESTION_LENGTH = 80;
export const MAX_INPUT_PLACEHOLDER_LENGTH = 40;
export const DEFAULT_INPUT_PLACEHOLDER = '输入消息';

export function createEmptyInteractionConfig(): AgentInteractionConfig {
  return {
    inputPlaceholder: '',
    suggestedQuestions: [],
    welcomeMessage: '',
  };
}

export function normalizeInteractionConfig(
  source?: Partial<AgentInteractionConfig> | Record<string, unknown>,
): AgentInteractionConfig {
  return {
    inputPlaceholder:
      typeof source?.inputPlaceholder === 'string'
        ? source.inputPlaceholder
        : '',
    suggestedQuestions: Array.isArray(source?.suggestedQuestions)
      ? source.suggestedQuestions.filter(
          (question): question is string => typeof question === 'string',
        )
      : [],
    welcomeMessage:
      typeof source?.welcomeMessage === 'string' ? source.welcomeMessage : '',
  };
}

export function buildInteractionConfigPayload(
  source?: Partial<AgentInteractionConfig> | Record<string, unknown>,
): AgentInteractionConfig {
  const normalized = normalizeInteractionConfig(source);
  return {
    inputPlaceholder: normalized.inputPlaceholder.trim(),
    suggestedQuestions: normalized.suggestedQuestions
      .map((question) => question.trim())
      .filter(Boolean),
    welcomeMessage: normalized.welcomeMessage.trim(),
  };
}

export function resolveInteractionDisplay(
  agent?: Pick<AgentInfo, 'interactionConfigJson' | 'name'>,
) {
  const config = buildInteractionConfigPayload(agent?.interactionConfigJson);
  const agentName = String(agent?.name || '').trim() || '智能体';
  return {
    inputPlaceholder: config.inputPlaceholder || DEFAULT_INPUT_PLACEHOLDER,
    suggestedQuestions: config.suggestedQuestions,
    welcomeMessage:
      config.welcomeMessage || `你好，我是 ${agentName}，有什么可以帮你？`,
  };
}

export function validateInteractionConfig(
  source?: Partial<AgentInteractionConfig> | Record<string, unknown>,
): AgentValidationIssue[] {
  const config = normalizeInteractionConfig(source);
  const issues: AgentValidationIssue[] = [];
  if (config.welcomeMessage.trim().length > MAX_WELCOME_MESSAGE_LENGTH) {
    issues.push({
      field: 'interaction.welcomeMessage',
      message: '欢迎语不能超过 300 个字符',
      nodeId: 'agent-base',
    });
  }
  if (/\r|\n/.test(config.inputPlaceholder)) {
    issues.push({
      field: 'interaction.inputPlaceholder',
      message: '输入提示仅支持单行文本',
      nodeId: 'agent-base',
    });
  } else if (
    config.inputPlaceholder.trim().length > MAX_INPUT_PLACEHOLDER_LENGTH
  ) {
    issues.push({
      field: 'interaction.inputPlaceholder',
      message: '输入提示不能超过 40 个字符',
      nodeId: 'agent-base',
    });
  }

  const questions = config.suggestedQuestions
    .map((question, index) => ({ index, value: question.trim() }))
    .filter((item) => item.value);
  if (questions.length > MAX_SUGGESTED_QUESTION_COUNT) {
    issues.push({
      field: 'interaction.suggestedQuestions',
      message: '猜你想问最多配置 6 条',
      nodeId: 'agent-base',
    });
  }
  const seenQuestions = new Set<string>();
  for (const question of questions) {
    if (question.value.length > MAX_SUGGESTED_QUESTION_LENGTH) {
      issues.push({
        field: `interaction.suggestedQuestions.${question.index}`,
        message: `第 ${question.index + 1} 条猜你想问不能超过 80 个字符`,
        nodeId: 'agent-base',
      });
    }
    if (seenQuestions.has(question.value)) {
      issues.push({
        field: `interaction.suggestedQuestions.${question.index}`,
        message: `第 ${question.index + 1} 条猜你想问与已有内容重复`,
        nodeId: 'agent-base',
      });
    }
    seenQuestions.add(question.value);
  }
  return issues;
}