import * as parse5 from 'parse5'; import treeAdapter = require('parse5/lib/tree-adapters/default'); import { URL } from 'url'; const urlRegex = /^https?:\/\/[\w\/:%#@$&?!()\[\]~.,=+\-]+/; const urlRegexFull = /^https?:\/\/[\w\/:%#@$&?!()\[\]~.,=+\-]+$/; export function fromHtml(html: string, hashtagNames?: string[]): string | null { if (html == null) return null; const dom = parse5.parseFragment(html); let text = ''; for (const n of dom.childNodes) { analyze(n); } return text.trim(); function getText(node: parse5.Node): string { if (treeAdapter.isTextNode(node)) return node.value; if (!treeAdapter.isElementNode(node)) return ''; if (node.nodeName === 'br') return '\n'; if (node.childNodes) { return node.childNodes.map(n => getText(n)).join(''); } return ''; } function appendChildren(childNodes: parse5.ChildNode[]): void { if (childNodes) { for (const n of childNodes) { analyze(n); } } } function analyze(node: parse5.Node) { if (treeAdapter.isTextNode(node)) { text += node.value; return; } // Skip comment or document type node if (!treeAdapter.isElementNode(node)) return; switch (node.nodeName) { case 'br': text += '\n'; break; case 'a': { const txt = getText(node); const rel = node.attrs.find(x => x.name === 'rel'); const href = node.attrs.find(x => x.name === 'href'); // ハッシュタグ if (hashtagNames && href && hashtagNames.map(x => x.toLowerCase()).includes(txt.toLowerCase())) { text += txt; // メンション } else if (txt.startsWith('@') && !(rel && rel.value.match(/^me /))) { const part = txt.split('@'); if (part.length === 2 && href) { //#region ホスト名部分が省略されているので復元する const acct = `${txt}@${(new URL(href.value)).hostname}`; text += acct; //#endregion } else if (part.length === 3) { text += txt; } // その他 } else { const generateLink = () => { if (!href && !txt) { return ''; } if (!href) { return txt; } if (!txt || txt === href.value) { // #6383: Missing text node if (href.value.match(urlRegexFull)) { return href.value; } else { return `<${href.value}>`; } } if (href.value.match(urlRegex) && !href.value.match(urlRegexFull)) { return `[${txt}](<${href.value}>)`; // #6846 } else { return `[${txt}](${href.value})`; } }; text += generateLink(); } break; } case 'h1': { text += '【'; appendChildren(node.childNodes); text += '】\n'; break; } case 'b': case 'strong': { text += '**'; appendChildren(node.childNodes); text += '**'; break; } case 'small': { text += '<small>'; appendChildren(node.childNodes); text += '</small>'; break; } case 's': case 'del': { text += '~~'; appendChildren(node.childNodes); text += '~~'; break; } case 'i': case 'em': { text += '<i>'; appendChildren(node.childNodes); text += '</i>'; break; } // block code (<pre><code>) case 'pre': { if (node.childNodes.length === 1 && node.childNodes[0].nodeName === 'code') { text += '\n```\n'; text += getText(node.childNodes[0]); text += '\n```\n'; } else { appendChildren(node.childNodes); } break; } // inline code (<code>) case 'code': { text += '`'; appendChildren(node.childNodes); text += '`'; break; } case 'blockquote': { const t = getText(node); if (t) { text += '> '; text += t.split('\n').join(`\n> `); } break; } case 'p': case 'h2': case 'h3': case 'h4': case 'h5': case 'h6': { text += '\n\n'; appendChildren(node.childNodes); break; } // other block elements case 'div': case 'header': case 'footer': case 'article': case 'li': case 'dt': case 'dd': { text += '\n'; appendChildren(node.childNodes); break; } default: // includes inline elements { appendChildren(node.childNodes); break; } } } }