"use client";

import { useRef, useState, useEffect } from "react";
import { useUpdateEffect } from "react-use";
import classNames from "classnames";

import { cn } from "@/lib/utils";
import { GridPattern } from "@/components/magic-ui/grid-pattern";
import { useEditor } from "@/hooks/useEditor";
import { useAi } from "@/hooks/useAi";
import { htmlTagToText } from "@/lib/html-tag-to-text";
import { AnimatedBlobs } from "@/components/animated-blobs";
import { AiLoading } from "../ask-ai/loading";
import { defaultHTML } from "@/lib/consts";
import { Button } from "@/components/ui/button";
import { LivePreview } from "../live-preview";
import { HistoryNotification } from "../history-notification";
import { AlertCircle } from "lucide-react";
import { api } from "@/lib/api";
import { toast } from "sonner";
import Loading from "@/components/loading";

export const Preview = ({ isNew }: { isNew: boolean }) => {
  const {
    project,
    device,
    isLoadingProject,
    currentTab,
    currentCommit,
    setCurrentCommit,
    currentPageData,
    pages,
    setCurrentPage,
  } = useEditor();
  const {
    isEditableModeEnabled,
    setSelectedElement,
    isAiWorking,
    globalAiLoading,
    setIsEditableModeEnabled,
  } = useAi();

  const iframeRef = useRef<HTMLIFrameElement>(null);

  // Inject event handling script
  const injectInteractivityScript = (html: string) => {
    const interactivityScript = `
      <script>        
        // Add event listeners and communicate with parent
        document.addEventListener('DOMContentLoaded', function() {
          let hoveredElement = null;
          let isEditModeEnabled = false;
          
          document.addEventListener('mouseover', function(event) {
            if (event.target !== document.body && event.target !== document.documentElement) {
              hoveredElement = event.target;
              
              const rect = event.target.getBoundingClientRect();
              const message = {
                type: 'ELEMENT_HOVERED',
                data: {
                  tagName: event.target.tagName,
                  rect: {
                    top: rect.top,
                    left: rect.left,
                    width: rect.width,
                    height: rect.height
                  },
                  element: event.target.outerHTML
                }
              };
              parent.postMessage(message, '*');
            }
          });
          
          document.addEventListener('mouseout', function(event) {
            hoveredElement = null;
            
            parent.postMessage({
              type: 'ELEMENT_MOUSE_OUT'
            }, '*');
          });
          
          // Handle clicks - prevent default only in edit mode
          document.addEventListener('click', function(event) {
            if (isEditModeEnabled) {
              event.preventDefault();
              event.stopPropagation();
              
              const rect = event.target.getBoundingClientRect();
              parent.postMessage({
                type: 'ELEMENT_CLICKED',
                data: {
                  tagName: event.target.tagName,
                  rect: {
                    top: rect.top,
                    left: rect.left,
                    width: rect.width,
                    height: rect.height
                  },
                  element: event.target.outerHTML
                }
              }, '*');
            } else {
              // Handle link clicks to navigate between pages
              const link = event.target.closest('a');
              if (link && link.href) {
                event.preventDefault();
                
                const url = new URL(link.href, window.location.href);
                
                // Check if it's a relative link (same origin)
                if (url.origin === window.location.origin || link.href.startsWith('/') || link.href.startsWith('./') || link.href.startsWith('../') || !link.href.includes('://')) {
                  // Extract the path from the link
                  let targetPath = link.getAttribute('href') || '';
                  
                  // Handle relative paths
                  if (targetPath.startsWith('./')) {
                    targetPath = targetPath.substring(2);
                  } else if (targetPath.startsWith('/')) {
                    targetPath = targetPath.substring(1);
                  }
                  
                  // If no extension, assume .html
                  if (!targetPath.includes('.') && !targetPath.includes('?') && !targetPath.includes('#')) {
                    targetPath = targetPath === '' ? 'index.html' : targetPath + '.html';
                  }
                  
                  // Send message to parent to navigate to the page
                  parent.postMessage({
                    type: 'NAVIGATE_TO_PAGE',
                    data: {
                      targetPath: targetPath
                    }
                  }, '*');
                } else {
                  // External link - open in new tab
                  window.open(link.href, '_blank');
                }
              }
            }
          });
          
          // Prevent form submissions when in edit mode
          document.addEventListener('submit', function(event) {
            if (isEditModeEnabled) {
              event.preventDefault();
              event.stopPropagation();
            }
          });
          
          // Prevent other navigation events when in edit mode
          document.addEventListener('keydown', function(event) {
            if (isEditModeEnabled && event.key === 'Enter' && (event.target.tagName === 'A' || event.target.tagName === 'BUTTON')) {
              event.preventDefault();
              event.stopPropagation();
            }
          });
          
          // Listen for messages from parent
          window.addEventListener('message', function(event) {
            if (event.data.type === 'ENABLE_EDIT_MODE') {
              isEditModeEnabled = true;
              document.body.style.userSelect = 'none';
              document.body.style.pointerEvents = 'auto';
            } else if (event.data.type === 'DISABLE_EDIT_MODE') {
              isEditModeEnabled = false;
              document.body.style.userSelect = '';
              document.body.style.pointerEvents = '';
            }
          });
          
          // Notify parent that script is ready
          parent.postMessage({
            type: 'IFRAME_SCRIPT_READY'
          }, '*');
        });
      </script>
    `;

    // Inject the script before closing body tag, or at the end if no body tag
    if (html.includes("</body>")) {
      return html.replace("</body>", `${interactivityScript}</body>`);
    } else {
      return html + interactivityScript;
    }
  };
  const [hoveredElement, setHoveredElement] = useState<{
    tagName: string;
    rect: { top: number; left: number; width: number; height: number };
  } | null>(null);
  const [isPromotingVersion, setIsPromotingVersion] = useState(false);
  const [stableHtml, setStableHtml] = useState<string>("");

  // Handle PostMessage communication with iframe
  useEffect(() => {
    const handleMessage = (event: MessageEvent) => {
      // Verify origin for security
      if (!event.origin.includes(window.location.origin)) {
        return;
      }

      const { type, data } = event.data;
      switch (type) {
        case "IFRAME_SCRIPT_READY":
          if (iframeRef.current?.contentWindow) {
            iframeRef.current.contentWindow.postMessage(
              {
                type: isEditableModeEnabled
                  ? "ENABLE_EDIT_MODE"
                  : "DISABLE_EDIT_MODE",
              },
              "*"
            );
          }
          break;
        case "ELEMENT_HOVERED":
          if (isEditableModeEnabled) {
            setHoveredElement(data);
          }
          break;
        case "ELEMENT_MOUSE_OUT":
          if (isEditableModeEnabled) {
            setHoveredElement(null);
          }
          break;
        case "ELEMENT_CLICKED":
          if (isEditableModeEnabled) {
            const mockElement = {
              tagName: data.tagName,
              getBoundingClientRect: () => data.rect,
              outerHTML: data.element,
            };
            setSelectedElement(mockElement as any);
            setIsEditableModeEnabled(false);
          }
          break;
        case "NAVIGATE_TO_PAGE":
          // Handle navigation between pages by updating currentPageData
          if (data.targetPath) {
            // Find the page in the pages array
            const targetPage = pages.find(
              (page) => page.path === data.targetPath
            );
            if (targetPage) {
              setCurrentPage(data.targetPath);
            } else {
              // If page doesn't exist, you might want to create it or show an error
              console.warn(`Page not found: ${data.targetPath}`);
              toast.error(`Page not found: ${data.targetPath}`);
            }
          }
          break;
      }
    };

    window.addEventListener("message", handleMessage);
    return () => window.removeEventListener("message", handleMessage);
  }, [setSelectedElement, isEditableModeEnabled, pages, setCurrentPage]);

  // Send edit mode state to iframe and clear hover state when disabled
  useUpdateEffect(() => {
    if (iframeRef.current?.contentWindow) {
      iframeRef.current.contentWindow.postMessage(
        {
          type: isEditableModeEnabled
            ? "ENABLE_EDIT_MODE"
            : "DISABLE_EDIT_MODE",
        },
        "*"
      );
    }

    // Clear hover state when edit mode is disabled
    if (!isEditableModeEnabled) {
      setHoveredElement(null);
    }
  }, [isEditableModeEnabled, stableHtml]);

  // Update stable HTML only when AI finishes working to prevent blinking
  useEffect(() => {
    if (!isAiWorking && !globalAiLoading && currentPageData?.html) {
      setStableHtml(currentPageData.html);
    }
  }, [isAiWorking, globalAiLoading, currentPageData?.html]);

  // Initialize stable HTML when component first loads
  useEffect(() => {
    if (
      currentPageData?.html &&
      !stableHtml &&
      !isAiWorking &&
      !globalAiLoading
    ) {
      setStableHtml(currentPageData.html);
    }
  }, [currentPageData?.html, stableHtml, isAiWorking, globalAiLoading]);

  const promoteVersion = async () => {
    setIsPromotingVersion(true);
    await api
      .post(
        `/me/projects/${project?.space_id}/commits/${currentCommit}/promote`
      )
      .then((res) => {
        if (res.data.ok) {
          setCurrentCommit(null);
          toast.success("Version promoted successfully");
        }
      })
      .catch((err) => {
        toast.error(err.response.data.error);
      });
    setIsPromotingVersion(false);
  };

  return (
    <div
      className={classNames(
        "bg-neutral-900/30 w-full h-[calc(100dvh-57px)] flex flex-col items-center justify-center relative z-1 lg:border-l border-neutral-800",
        {
          "max-lg:h-0": currentTab === "chat",
          "max-lg:h-full": currentTab === "preview",
        }
      )}
    >
      <GridPattern
        x={-1}
        y={-1}
        strokeDasharray={"4 2"}
        className={cn(
          "[mask-image:radial-gradient(900px_circle_at_center,white,transparent)] opacity-40"
        )}
      />
      {!isAiWorking && hoveredElement && isEditableModeEnabled && (
        <div
          className="cursor-pointer absolute bg-sky-500/10 border-[2px] border-dashed border-sky-500 rounded-r-lg rounded-b-lg p-3 z-10 pointer-events-none"
          style={{
            top: hoveredElement.rect.top,
            left: hoveredElement.rect.left,
            width: hoveredElement.rect.width,
            height: hoveredElement.rect.height,
          }}
        >
          <span className="bg-sky-500 rounded-t-md text-sm text-neutral-100 px-2 py-0.5 -translate-y-7 absolute top-0 left-0">
            {htmlTagToText(hoveredElement.tagName.toLowerCase())}
          </span>
        </div>
      )}
      {isNew && !isLoadingProject ? (
        <iframe
          className={classNames(
            "w-full select-none transition-all duration-200 bg-black h-full",
            {
              "lg:max-w-md lg:mx-auto lg:!rounded-[42px] lg:border-[8px] lg:border-neutral-700 lg:shadow-2xl lg:h-[80dvh] lg:max-h-[996px]":
                device === "mobile",
            }
          )}
          srcDoc={defaultHTML}
        />
      ) : isLoadingProject || globalAiLoading ? (
        <div className="w-full h-full flex items-center justify-center relative">
          <div className="py-10 w-full relative z-1 max-w-3xl mx-auto text-center">
            <AiLoading
              text={isLoadingProject ? "Fetching your project..." : undefined}
              className="flex-col"
            />
            <AnimatedBlobs />
            <AnimatedBlobs />
          </div>
          <LivePreview
            currentPageData={currentPageData}
            isAiWorking={isAiWorking}
            defaultHTML={defaultHTML}
            className="bottom-4 left-4"
          />
        </div>
      ) : (
        <>
          <iframe
            id="preview-iframe"
            ref={iframeRef}
            className={classNames(
              "w-full select-none transition-all duration-200 bg-black h-full",
              {
                "lg:max-w-md lg:mx-auto lg:!rounded-[42px] lg:border-[8px] lg:border-neutral-700 lg:shadow-2xl lg:h-[80dvh] lg:max-h-[996px]":
                  device === "mobile",
              }
            )}
            src={
              currentCommit
                ? `https://${project?.space_id?.replaceAll(
                    "/",
                    "-"
                  )}--rev-${currentCommit.slice(0, 7)}.static.hf.space`
                : undefined
            }
            srcDoc={
              !currentCommit
                ? injectInteractivityScript(stableHtml || "")
                : undefined
            }
            sandbox="allow-scripts allow-same-origin allow-popups allow-popups-to-escape-sandbox"
            allow="accelerometer; ambient-light-sensor; autoplay; battery; camera; clipboard-read; clipboard-write; display-capture; document-domain; encrypted-media; fullscreen; geolocation; gyroscope; layout-animations; legacy-image-formats; magnetometer; microphone; midi; oversized-images; payment; picture-in-picture; publickey-credentials-get; serial; sync-xhr; usb; vr ; wake-lock; xr-spatial-tracking"
          />
          <HistoryNotification
            isVisible={!!currentCommit}
            isPromotingVersion={isPromotingVersion}
            onPromoteVersion={promoteVersion}
            onGoBackToCurrent={() => setCurrentCommit(null)}
          />
        </>
      )}
    </div>
  );
};