import disclaimerMarkdown from '../../../media/files/disclaimer.md?raw';
import privacyPolicyMarkdown from '../../../media/files/privacy_policy.md?raw';
import userAgreementMarkdown from '../../../media/files/user_agreement.md?raw';

export type LegalDocumentId =
  | 'user-agreement'
  | 'privacy-policy'
  | 'disclaimer';

export type LegalDocumentBlock =
  | {
      type: 'heading';
      level: 2 | 3;
      text: string;
    }
  | {
      type: 'paragraph';
      text: string;
    }
  | {
      type: 'list';
      items: string[];
    };

export type LegalDocument = {
  id: LegalDocumentId;
  title: string;
  markdown: string;
  blocks: LegalDocumentBlock[];
};

export const LEGAL_CONSENT_STORAGE_KEY =
  'genarrative.auth.legal-consent.v1';
export const ICP_RECORD_NUMBER = '京ICP备2026025677号';
export const ICP_RECORD_URL = 'https://beian.miit.gov.cn/';

function normalizeMarkdownInlineText(value: string) {
  return value.replace(/`([^`]+)`/gu, '$1').trim();
}

function pushParagraph(
  blocks: LegalDocumentBlock[],
  lines: string[],
) {
  if (lines.length === 0) {
    return;
  }

  const text = normalizeMarkdownInlineText(lines.join('\n'));
  if (text) {
    blocks.push({ type: 'paragraph', text });
  }
  lines.length = 0;
}

function pushList(blocks: LegalDocumentBlock[], items: string[]) {
  if (items.length === 0) {
    return;
  }

  blocks.push({
    type: 'list',
    items: items.map(normalizeMarkdownInlineText).filter(Boolean),
  });
  items.length = 0;
}

function parseLegalMarkdown(markdown: string): LegalDocumentBlock[] {
  const blocks: LegalDocumentBlock[] = [];
  const paragraphLines: string[] = [];
  const listItems: string[] = [];

  markdown.split(/\r?\n/u).forEach((rawLine) => {
    const line = rawLine.trim();

    if (!line) {
      pushParagraph(blocks, paragraphLines);
      pushList(blocks, listItems);
      return;
    }

    const headingMatch = /^(#{2,3})\s+(.+)$/u.exec(line);
    if (headingMatch) {
      pushParagraph(blocks, paragraphLines);
      pushList(blocks, listItems);
      blocks.push({
        type: 'heading',
        level: headingMatch[1]?.length === 2 ? 2 : 3,
        text: normalizeMarkdownInlineText(headingMatch[2] ?? ''),
      });
      return;
    }

    const listMatch = /^(?:[-*]|\d+[.)、])\s+(.+)$/u.exec(line);
    if (listMatch) {
      pushParagraph(blocks, paragraphLines);
      listItems.push(listMatch[1] ?? '');
      return;
    }

    pushList(blocks, listItems);
    paragraphLines.push(line);
  });

  pushParagraph(blocks, paragraphLines);
  pushList(blocks, listItems);
  return blocks;
}

const legalDocumentDefinitions = [
  {
    id: 'user-agreement',
    title: '用户协议',
    markdown: userAgreementMarkdown,
  },
  {
    id: 'privacy-policy',
    title: '隐私政策',
    markdown: privacyPolicyMarkdown,
  },
  {
    id: 'disclaimer',
    title: '免责声明',
    markdown: disclaimerMarkdown,
  },
] satisfies Array<{
  id: LegalDocumentId;
  title: string;
  markdown: string;
}>;

export const LEGAL_DOCUMENTS: LegalDocument[] = legalDocumentDefinitions.map(
  (document) => ({
    ...document,
    blocks: parseLegalMarkdown(document.markdown),
  }),
);

export function getLegalDocument(id: LegalDocumentId) {
  return LEGAL_DOCUMENTS.find((document) => document.id === id) ?? null;
}

export function readStoredLegalConsent() {
  if (typeof window === 'undefined') {
    return false;
  }

  return window.localStorage.getItem(LEGAL_CONSENT_STORAGE_KEY) === 'true';
}

export function persistLegalConsent() {
  if (typeof window === 'undefined') {
    return;
  }

  window.localStorage.setItem(LEGAL_CONSENT_STORAGE_KEY, 'true');
}