"use strict"; (() => { // src/constants.ts var PROD_BASE = "https://ui-patterns.langchain.com"; // src/ChatLangChainEmbed.ts var MOBILE_BREAKPOINT = 768; var ROOT_OPEN_CLASS = "lc-chat-widget-open"; var LOCAL_EMBED_BASE_URL = "http://localhost:4100"; var PROD_EMBED_BASE_URL = `${PROD_BASE}/react`; var CHAT_APP_URL = "https://chat.langchain.com/"; var PANEL_TRANSITION = "300ms cubic-bezier(0.22, 1, 0.36, 1)"; var WIDGET_STYLE_ID = "lc-chat-widget-style"; var WIDGET_INIT_KEY = "__lcChatWidgetInitialized"; var MIN_PANEL_WIDTH = 280; var MAX_PANEL_WIDTH_RATIO = 0.7; function lcIsLocalhost() { if (typeof window === "undefined") return false; var h = window.location.hostname; return h === "localhost" || h === "127.0.0.1" || h === "[::1]"; } function lcDetectPageTheme() { if (typeof document === "undefined") return "light"; var el = document.documentElement; if (el.classList.contains("dark")) return "dark"; if (el.getAttribute("data-theme") === "dark") return "dark"; if (el.style.colorScheme === "dark") return "dark"; return "light"; } function lcGetEmbedSrc(apiUrl, assistantId, sessionBust) { var baseUrl = lcIsLocalhost() ? LOCAL_EMBED_BASE_URL : PROD_EMBED_BASE_URL; var params = []; if (apiUrl) params.push("apiUrl=" + encodeURIComponent(apiUrl)); if (assistantId) params.push("assistantId=" + encodeURIComponent(assistantId)); if (sessionBust !== void 0) { params.push("_lcSession=" + encodeURIComponent(String(sessionBust))); } var query = params.length ? "?" + params.join("&") : ""; return baseUrl + "/" + query + "#/chat-langchain"; } function lcGetPanelWidth() { if (window.innerWidth <= MOBILE_BREAKPOINT) return 0; return Math.round(Math.max(360, Math.min(window.innerWidth * 0.3, 480))); } var WIDGET_CSS = ( /*css*/ ` :root { --lc-chat-panel-width: 420px; --lc-chat-widget-bg-light: #161F34; --lc-chat-widget-bg-dark: #006DDD; --lc-chat-widget-surface-light: #ffffff; --lc-chat-widget-surface-dark: #030710; --lc-chat-widget-border-light: #dde4ef; --lc-chat-widget-border-dark: rgb(38, 38, 38); --lc-chat-widget-shadow-light: 0 20px 60px rgba(3, 7, 16, 0.15); --lc-chat-widget-shadow-dark: 0 20px 60px rgba(0, 0, 0, 0.5); } #lc-chat-widget-close:focus-visible, #lc-chat-widget-open-link:focus-visible, #lc-chat-widget-new-thread:focus-visible, #lc-chat-widget-history:focus-visible { outline: 2px solid #7fc8ff; outline-offset: 3px; } #lc-chat-widget-close svg, #lc-chat-widget-open-link svg, #lc-chat-widget-new-thread svg, #lc-chat-widget-history svg { width: 18px; height: 18px; } #lc-chat-widget-panel { position: fixed; top: 0; right: 0; z-index: 9998; width: var(--lc-chat-panel-width); height: 100vh; display: flex; flex-direction: column; transform: translateX(100%); transition: transform ${PANEL_TRANSITION}; background: var(--lc-chat-widget-surface-light); border-left: 1px solid var(--lc-chat-widget-border-light); } /* Mintlify (and similar) top banner \u2014 keep panel below fixed banner */ #lc-chat-widget-panel[data-lc-banner-offset="true"] { margin-top: 40px; height: calc(100vh - 40px); } html.${ROOT_OPEN_CLASS} #lc-chat-widget-panel { transform: translateX(0); } #lc-chat-widget-panel[data-theme='dark'] { background: var(--lc-chat-widget-surface-dark); border-left-color: var(--lc-chat-widget-border-dark); } #lc-chat-widget-header { display: flex; align-items: center; justify-content: space-between; gap: 12px; padding: 14px 18px 13px; border-bottom: 1px solid var(--lc-chat-widget-border-light); } #lc-chat-widget-panel[data-theme='dark'] #lc-chat-widget-header { border-bottom-color: var(--lc-chat-widget-border-dark); } #lc-chat-widget-title { margin: 0; font: 600 16px/1.2 'Inter', sans-serif; color: #030710; } #lc-chat-widget-panel[data-theme='dark'] #lc-chat-widget-title { color: #ffffff; } #lc-chat-widget-actions { display: flex; align-items: center; gap: 8px; } #lc-chat-widget-open-link, #lc-chat-widget-close, #lc-chat-widget-new-thread, #lc-chat-widget-history { width: 28px; height: 28px; border: 0; border-radius: 999px; display: inline-flex; align-items: center; justify-content: center; color: #161F34; background: transparent; text-decoration: none; cursor: pointer; transition: background 150ms ease, color 150ms ease; } #lc-chat-widget-open-link:hover, #lc-chat-widget-close:hover, #lc-chat-widget-new-thread:hover, #lc-chat-widget-history:hover { background: rgba(22, 31, 52, 0.08); } #lc-chat-widget-panel[data-theme='dark'] :is(#lc-chat-widget-open-link, #lc-chat-widget-close, #lc-chat-widget-new-thread, #lc-chat-widget-history) { color: #c8d4e8; } #lc-chat-widget-panel[data-theme='dark'] :is(#lc-chat-widget-open-link:hover, #lc-chat-widget-close:hover, #lc-chat-widget-new-thread:hover, #lc-chat-widget-history:hover) { background: rgba(127, 200, 255, 0.08); color: #ffffff; } #lc-chat-widget-new-thread { display: none; } #lc-chat-widget-panel[data-thread-started='true'] #lc-chat-widget-new-thread { display: inline-flex; } #lc-chat-widget-history { display: none; } #lc-chat-widget-panel[data-saved-threads='true'] #lc-chat-widget-history { display: inline-flex; } #lc-chat-widget-panel[data-history-open='true'] #lc-chat-widget-history { background: rgba(127, 200, 255, 0.12); color: #006ddd; } #lc-chat-widget-panel[data-theme='dark'][data-history-open='true'] #lc-chat-widget-history { background: rgba(127, 200, 255, 0.12); color: #ffffff; } #lc-chat-widget-body { position: relative; flex: 1 1 auto; min-height: 0; } #lc-chat-widget-iframe { width: 100%; height: 100%; border: 0; opacity: 0; transition: opacity 200ms ease; background: #ffffff; } #lc-chat-widget-panel[data-theme='dark'] #lc-chat-widget-iframe { background: #030710; } #lc-chat-widget-panel[data-ready='true'] #lc-chat-widget-iframe { opacity: 1; } #lc-chat-widget-loading { position: absolute; inset: 0; display: flex; align-items: center; justify-content: center; background: rgba(255, 255, 255, 0.92); } #lc-chat-widget-panel[data-theme='dark'] #lc-chat-widget-loading { background: rgba(3, 7, 16, 0.94); } #lc-chat-widget-panel[data-ready='true'] #lc-chat-widget-loading { display: none; } #lc-chat-widget-spinner { width: 28px; height: 28px; border: 3px solid rgba(22, 31, 52, 0.12); border-top-color: #006DDD; border-radius: 999px; animation: lc-chat-widget-spin 0.8s linear infinite; } #lc-chat-widget-panel[data-theme='dark'] #lc-chat-widget-spinner { border-color: rgba(127, 200, 255, 0.15); border-top-color: #7FC8FF; } @keyframes lc-chat-widget-spin { to { transform: rotate(360deg); } } @media (max-width: 768px) { :root { --lc-chat-panel-width: 100vw; } #lc-chat-widget-panel { width: 100vw; } } #lc-chat-widget-resize-handle { position: absolute; top: 0; left: -4px; width: 8px; height: 100%; cursor: ew-resize; z-index: 10; display: flex; align-items: center; justify-content: center; } #lc-chat-widget-resize-handle::before { content: ''; width: 3px; height: 36px; border-radius: 999px; background: transparent; transition: background 150ms ease; } #lc-chat-widget-resize-handle:hover::before, #lc-chat-widget-resize-handle.lc-dragging::before { background: rgba(22, 31, 52, 0.2); } #lc-chat-widget-panel[data-theme='dark'] #lc-chat-widget-resize-handle:hover::before, #lc-chat-widget-panel[data-theme='dark'] #lc-chat-widget-resize-handle.lc-dragging::before { background: rgba(127, 200, 255, 0.3); } @media (max-width: 768px) { #lc-chat-widget-resize-handle { display: none; } } /* Mintlify "On this page" (#content-side-layout) uses full viewport width for layout; hide it while the chat panel is open so the main column is not squeezed on viewports < 1800px. */ @media (max-width: 1799px) { html.${ROOT_OPEN_CLASS} #content-side-layout { display: none !important; } } ` ); function ChatLangChainEmbed({ theme, apiUrl, assistantId, onReady }) { if (typeof window === "undefined") return null; if (window[WIDGET_INIT_KEY]) return null; window[WIDGET_INIT_KEY] = true; var panelReady = false; var panelOpen = false; var iframe = null; var fallbackTimer = 0; var appRoot = null; var currentPanelWidth = lcGetPanelWidth(); var isDragging = false; var dragStartX = 0; var dragStartWidth = 0; if (!document.getElementById(WIDGET_STYLE_ID)) { var style = document.createElement("style"); style.id = WIDGET_STYLE_ID; style.textContent = WIDGET_CSS; document.head.appendChild(style); } var panel = document.createElement("aside"); panel.id = "lc-chat-widget-panel"; panel.setAttribute("aria-label", "Chat LangChain"); panel.setAttribute("data-ready", "false"); panel.setAttribute("data-theme", lcDetectPageTheme()); panel.innerHTML = /*html*/ `

`; document.body.appendChild(panel); function syncBannerPanelOffset() { var hasBanner = !!document.getElementById("banner"); panel.setAttribute("data-lc-banner-offset", hasBanner ? "true" : "false"); } syncBannerPanelOffset(); var bannerOffsetRaf = 0; var bannerObserver = new MutationObserver(function() { if (bannerOffsetRaf) return; bannerOffsetRaf = requestAnimationFrame(function() { bannerOffsetRaf = 0; syncBannerPanelOffset(); }); }); bannerObserver.observe(document.body, { childList: true, subtree: true }); var panelBody = document.getElementById("lc-chat-widget-body"); var closeButton = document.getElementById("lc-chat-widget-close"); var historyButton = document.getElementById("lc-chat-widget-history"); var newThreadButton = document.getElementById("lc-chat-widget-new-thread"); var openLink = document.getElementById("lc-chat-widget-open-link"); var resizeHandle = document.getElementById("lc-chat-widget-resize-handle"); function syncTheme() { var t = theme ?? lcDetectPageTheme(); panel.setAttribute("data-theme", t); if (iframe && panelReady && iframe.contentWindow) { iframe.contentWindow.postMessage({ type: "CHAT_LC_SET_THEME", theme: t }, "*"); } } function ensureAppRoot() { if (appRoot && document.body.contains(appRoot)) return appRoot; appRoot = document.querySelector("body > .antialiased") || document.querySelector("body > div.antialiased") || document.querySelector("body > div:not(#lc-chat-widget-panel)"); return appRoot; } function clampWidth(w) { return Math.round( Math.max(MIN_PANEL_WIDTH, Math.min(window.innerWidth * MAX_PANEL_WIDTH_RATIO, w)) ); } function updatePanelWidth(w) { currentPanelWidth = clampWidth(w); document.documentElement.style.setProperty("--lc-chat-panel-width", currentPanelWidth + "px"); var root = ensureAppRoot(); if (root && panelOpen) root.style.marginRight = currentPanelWidth + "px"; } function updateLayout() { var root = ensureAppRoot(); if (window.innerWidth <= MOBILE_BREAKPOINT) { document.documentElement.style.setProperty("--lc-chat-panel-width", "100vw"); } else { currentPanelWidth = clampWidth(currentPanelWidth); document.documentElement.style.setProperty("--lc-chat-panel-width", currentPanelWidth + "px"); } if (root) { root.style.transition = "margin-right " + PANEL_TRANSITION; root.style.marginRight = panelOpen && window.innerWidth > MOBILE_BREAKPOINT ? currentPanelWidth + "px" : ""; } } function ensureIframe() { if (iframe) return; iframe = document.createElement("iframe"); iframe.id = "lc-chat-widget-iframe"; iframe.src = lcGetEmbedSrc(apiUrl, assistantId); iframe.title = "Chat LangChain"; iframe.setAttribute("sandbox", "allow-scripts allow-same-origin allow-forms allow-popups"); iframe.setAttribute("allow", "clipboard-write"); iframe.addEventListener("load", function handleLoad() { if (panelReady) return; fallbackTimer = window.setTimeout(setPanelReady, 1500); }); panelBody.appendChild(iframe); } function sendPageContext() { if (iframe && panelReady && iframe.contentWindow) { iframe.contentWindow.postMessage( { type: "CHAT_LC_SET_CONTEXT", pageUrl: window.location.href }, "*" ); } } function setPanelReady() { if (panelReady) return; panelReady = true; panel.setAttribute("data-ready", "true"); if (fallbackTimer) { window.clearTimeout(fallbackTimer); fallbackTimer = 0; } syncTheme(); sendPageContext(); if (onReady) onReady(); } function updateOpenLink(threadId) { if (!openLink) return; if (threadId) { openLink.href = CHAT_APP_URL + "?threadId=" + encodeURIComponent(threadId); } else { openLink.href = CHAT_APP_URL; } } function markThreadStarted() { panel.setAttribute("data-thread-started", "true"); } function setHistoryPanelOpen(open) { panel.setAttribute("data-history-open", open ? "true" : "false"); historyButton.setAttribute("aria-pressed", open ? "true" : "false"); } function setSavedThreadsIndicator(has) { panel.setAttribute("data-saved-threads", has ? "true" : "false"); } function startNewThread() { panel.setAttribute("data-thread-started", "false"); setHistoryPanelOpen(false); updateOpenLink(null); if (fallbackTimer) { window.clearTimeout(fallbackTimer); fallbackTimer = 0; } ensureIframe(); if (!iframe) return; panelReady = false; panel.setAttribute("data-ready", "false"); iframe.src = lcGetEmbedSrc(apiUrl, assistantId, Date.now()); } function openPanel() { ensureIframe(); panelOpen = true; document.documentElement.classList.add(ROOT_OPEN_CLASS); updateLayout(); sendPageContext(); } function closePanel() { panelOpen = false; document.documentElement.classList.remove(ROOT_OPEN_CLASS); updateLayout(); setHistoryPanelOpen(false); if (iframe && iframe.contentWindow) { iframe.contentWindow.postMessage({ type: "CHAT_LC_SET_HISTORY_VIEW", open: false }, "*"); } } document.addEventListener( "click", function lcChatTriggerCapture(e) { var t = e.target; if (!(t instanceof Element)) return; var anchor = t.closest('a[href^="https://chat.langchain.com"]'); if (!anchor || anchor.closest("#lc-chat-widget-panel")) return; e.preventDefault(); openPanel(); }, true ); var origPushState = history.pushState.bind(history); var origReplaceState = history.replaceState.bind(history); function afterDocNav() { queueMicrotask(sendPageContext); } history.pushState = function(data, unused, url) { var r = origPushState(data, unused, url); afterDocNav(); return r; }; history.replaceState = function(data, unused, url) { var r = origReplaceState(data, unused, url); afterDocNav(); return r; }; closeButton.addEventListener("click", closePanel); newThreadButton.addEventListener("click", startNewThread); window.addEventListener("keydown", function handleKeydown(event) { if (event.key === "Escape" && panelOpen) { closePanel(); return; } if (event.key === "i" && (event.metaKey || event.ctrlKey)) { event.preventDefault(); if (panelOpen) closePanel(); else openPanel(); } }); window.addEventListener("resize", updateLayout, { passive: true }); window.addEventListener("popstate", sendPageContext); window.addEventListener("hashchange", sendPageContext); historyButton.addEventListener("click", function() { ensureIframe(); if (!iframe || !iframe.contentWindow) return; iframe.contentWindow.postMessage({ type: "CHAT_LC_TOGGLE_HISTORY" }, "*"); }); window.addEventListener("message", function handleMessages(event) { if (!event.data) return; if (event.data.type === "CHAT_LC_READY") setPanelReady(); if (event.data.type === "CHAT_LC_PROMPT_SENT") markThreadStarted(); if (event.data.type === "CHAT_LC_THREAD_ID") { updateOpenLink(event.data.threadId ?? null); if (event.data.threadId) markThreadStarted(); } if (event.data.type === "CHAT_LC_HISTORY_VIEW" && typeof event.data.open === "boolean") { setHistoryPanelOpen(event.data.open); } if (event.data.type === "CHAT_LC_HAS_SAVED_THREADS" && typeof event.data.has === "boolean") { setSavedThreadsIndicator(event.data.has); } }); resizeHandle.addEventListener("mousedown", function(e) { if (window.innerWidth <= MOBILE_BREAKPOINT) return; isDragging = true; dragStartX = e.clientX; dragStartWidth = currentPanelWidth; resizeHandle.classList.add("lc-dragging"); document.body.style.cursor = "ew-resize"; document.body.style.userSelect = "none"; if (iframe) iframe.style.pointerEvents = "none"; e.preventDefault(); }); document.addEventListener("mousemove", function(e) { if (!isDragging) return; updatePanelWidth(dragStartWidth + (dragStartX - e.clientX)); }); document.addEventListener("mouseup", function() { if (!isDragging) return; isDragging = false; resizeHandle.classList.remove("lc-dragging"); document.body.style.cursor = ""; document.body.style.userSelect = ""; if (iframe) iframe.style.pointerEvents = ""; }); var themeObserver = new MutationObserver(syncTheme); themeObserver.observe(document.documentElement, { attributes: true, attributeFilter: ["class", "data-theme", "style"] }); syncTheme(); updateLayout(); return null; } ChatLangChainEmbed({}); })();

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