/**
 * The answer side of ask_clarifying_questions: submitted payload, persisted
 * answers for the settled card, and the Mixpanel properties.
 */

import {
  isQuestionComplete,
  SOMETHING_ELSE_LABEL,
  type ClarifyingQuestion,
  type QuestionState,
  type SelectedAnswer,
} from './questionsUtils';

/**
 * Completed questions only; the backend marks the rest skipped. `excludeIndex`
 * drops a just-skipped question, whose cleared state has not re-rendered yet.
 */
export function buildAnswersPayload(
  questions: ClarifyingQuestion[],
  states: Record<number, QuestionState>,
  excludeIndex?: number,
): SelectedAnswer[] {
  return questions
    .map((question, index) => ({ question, index }))
    .filter(({ index }) => index !== excludeIndex)
    .filter(({ question, index }) => isQuestionComplete(question, states[index]))
    .map(({ question, index }) => {
      const state = states[index];
      const customText = state.customText.trim();
      const answer: SelectedAnswer = { question_index: index };
      if (question.multi_select) {
        answer.selected_labels = state.answer.selected_labels ?? [];
      } else if (state.answer.selected_label) {
        answer.selected_label = state.answer.selected_label;
      }
      if (customText) answer.custom_text = customText;
      return answer;
    });
}

/** Answer text for the settled summary, from persisted user_input.answers. */
export function answerTextFromSelected(answer: SelectedAnswer): string {
  const custom = answer.custom_text?.trim();
  if (answer.selected_labels && answer.selected_labels.length > 0) {
    return answer.selected_labels
      .map((l) => (l === SOMETHING_ELSE_LABEL && custom ? custom : l))
      .filter((l) => l !== SOMETHING_ELSE_LABEL || custom)
      .join(', ');
  }
  if (custom) return custom;
  if (answer.selected_label && answer.selected_label !== SOMETHING_ELSE_LABEL) return answer.selected_label;
  return '';
}

/** Tolerant of shape drift in older persisted calls. */
export function persistedAnswers(userInput: unknown): SelectedAnswer[] {
  const answers = (userInput as { answers?: unknown } | null)?.answers;
  if (!Array.isArray(answers)) return [];
  return answers.filter(
    (a): a is SelectedAnswer => !!a && typeof a === 'object' && typeof (a as SelectedAnswer).question_index === 'number',
  );
}

/**
 * Answered questions only — listing a skipped one reads as a dropped answer
 * (web QuestionListDisplay parity).
 */
export function answeredQuestionRows(
  questions: ClarifyingQuestion[],
  answers: SelectedAnswer[],
): { question: string; answerText: string }[] {
  const answersByQuestion = new Map(answers.map((answer) => [answer.question_index, answer]));
  return questions
    .map((question, index) => ({ question, answer: answersByQuestion.get(index) }))
    .filter((row) => !!row.answer)
    .map((row) => ({ question: row.question.question, answerText: answerTextFromSelected(row.answer!) }));
}

/**
 * Names and shapes mirror the web events so both stitch into one report; app_id
 * and platform are already super-properties here.
 */
export function buildClarificationSuggestedProperties(questions: ClarifyingQuestion[]) {
  return {
    number_of_questions: questions.length,
    options_per_question: questions.map((question) => question.options.length),
    multi_select_per_question: questions.map((question) => question.multi_select ?? false),
  };
}

export function buildClarificationSubmittedProperties(
  questions: ClarifyingQuestion[],
  answers: SelectedAnswer[],
) {
  return {
    selected_answers: answers.filter(
      (answer) =>
        (answer.selected_label && answer.selected_label !== SOMETHING_ELSE_LABEL) ||
        (answer.selected_labels?.length ?? 0) > 0,
    ).length,
    something_else_answers: answers.filter((answer) => !!answer.custom_text).length,
    multi_select_questions: questions.filter((question) => question.multi_select).length,
    multi_select_answered: answers.filter(
      (answer) => questions[answer.question_index]?.multi_select && (answer.selected_labels?.length ?? 0) > 0,
    ).length,
  };
}