import { AppBskyRichtextFacet, RichText } from "@atproto/api";
import { useAtom } from "jotai";
import { Dialog } from "radix-ui";
import { useEffect, useRef, useState } from "react";

import { useAuth } from "~/providers/UnifiedAuthProvider";
import { composerAtom } from "~/utils/atoms";
import { useQueryPost } from "~/utils/useQuery";

import { ProfileThing } from "./Login";
import { Button } from "./radix-m3-rd/Button";
import { UniversalPostRendererATURILoader } from "./UniversalPostRenderer";

const MAX_POST_LENGTH = 300;

export function Composer() {
  const [composerState, setComposerState] = useAtom(composerAtom);
  const [closeConfirmState, setCloseConfirmState] = useState<boolean>(false);
  const { agent } = useAuth();

  const [postText, setPostText] = useState("");
  const [posting, setPosting] = useState(false);
  const [postSuccess, setPostSuccess] = useState(false);
  const [postError, setPostError] = useState<string | null>(null);

  useEffect(() => {
    setPostText("");
    setPosting(false);
    setPostSuccess(false);
    setPostError(null);
  }, [composerState.kind]);

  const parentUri =
    composerState.kind === "reply"
      ? composerState.parent
      : composerState.kind === "quote"
        ? composerState.subject
        : undefined;

  const { data: parentPost, isLoading: isParentLoading } =
    useQueryPost(parentUri);

  async function handlePost() {
    if (!agent || !postText.trim() || postText.length > MAX_POST_LENGTH) return;

    setPosting(true);
    setPostError(null);

    try {
      const rt = new RichText({ text: postText });
      await rt.detectFacets(agent);

      if (rt.facets?.length) {
      rt.facets = rt.facets.filter((item) => {
        if (item.$type !== "app.bsky.richtext.facet") return true;
        if (!item.features?.length) return true;

        item.features = item.features.filter((feature) => {
          if (feature.$type !== "app.bsky.richtext.facet#mention") return true;
          const did = feature.$type === "app.bsky.richtext.facet#mention" ? (feature as AppBskyRichtextFacet.Mention)?.did : undefined;
          return typeof did === "string" && did.startsWith("did:");
        });

        return item.features.length > 0;
      });
    }

      const record: Record<string, unknown> = {
        $type: "app.bsky.feed.post",
        text: rt.text,
        facets: rt.facets,
        createdAt: new Date().toISOString(),
      };

      if (composerState.kind === "reply" && parentPost) {
        record.reply = {
          root: parentPost.value?.reply?.root ?? {
            uri: parentPost.uri,
            cid: parentPost.cid,
          },
          parent: {
            uri: parentPost.uri,
            cid: parentPost.cid,
          },
        };
      }

      if (composerState.kind === "quote" && parentPost) {
        record.embed = {
          $type: "app.bsky.embed.record",
          record: {
            uri: parentPost.uri,
            cid: parentPost.cid,
          },
        };
      }

      await agent.com.atproto.repo.createRecord({
        collection: "app.bsky.feed.post",
        repo: agent.assertDid,
        record,
      });

      setPostSuccess(true);
      setPostText("");

      setTimeout(() => {
        setPostSuccess(false);
        setComposerState({ kind: "closed" });
      }, 1500);
    } catch (e: any) {
      setPostError(e?.message || "Failed to post");
    } finally {
      setPosting(false);
    }
  }

  const getPlaceholder = () => {
    switch (composerState.kind) {
      case "reply":
        return "Post your reply";
      case "quote":
        return "Add a comment...";
      case "root":
      default:
        return "What's happening?!";
    }
  };

  const charsLeft = MAX_POST_LENGTH - postText.length;
  const isPostButtonDisabled =
    posting || !postText.trim() || isParentLoading || charsLeft < 0;

  function handleAttemptClose() {
    if (postText.trim() && !posting) {
      setCloseConfirmState(true);
    } else {
      setComposerState({ kind: "closed" });
    }
  }

  function handleConfirmClose() {
    setComposerState({ kind: "closed" });
    setCloseConfirmState(false);
    setPostText("");
  }

  return (
    <>
      <Dialog.Root
        open={composerState.kind !== "closed"}
        onOpenChange={(open) => {
          if (!open) handleAttemptClose();
        }}
      >
        <Dialog.Portal>
          <Dialog.Overlay className="disablegutter fixed inset-0 z-50 bg-black/40 dark:bg-black/50 data-[state=open]:animate-fadeIn" />

          <Dialog.Content className="fixed overflow-y-auto gutter inset-0 z-50 flex items-start justify-center pt-10 sm:pt-20 pb-[50dvh] sm:pb-[50dvh]">
            <div className="bg-gray-50 dark:bg-gray-950 border border-gray-200 dark:border-gray-700 rounded-2xl shadow-xl w-full max-w-xl relative mx-4">
              <div className="flex flex-row justify-between p-2">
                <Dialog.Close asChild>
                  <button
                    className="h-8 w-8 flex items-center justify-center rounded-full text-gray-600 dark:text-gray-300 hover:bg-gray-100 dark:hover:bg-gray-800"
                    disabled={posting}
                    aria-label="Close"
                    onClick={handleAttemptClose}
                  >
                    <svg
                      xmlns="http://www.w3.org/2000/svg"
                      width="20"
                      height="20"
                      viewBox="0 0 24 24"
                      fill="none"
                      stroke="currentColor"
                      strokeWidth="2.5"
                      strokeLinecap="round"
                      strokeLinejoin="round"
                    >
                      <line x1="18" y1="6" x2="6" y2="18"></line>
                      <line x1="6" y1="6" x2="18" y2="18"></line>
                    </svg>
                  </button>
                </Dialog.Close>

                <div className="flex-1" />
                <div className="flex items-center gap-4">
                  <span
                    className={`text-sm ${charsLeft < 0 ? "text-red-500" : "text-gray-500"}`}
                  >
                    {charsLeft}
                  </span>
                  <Button
                    onClick={handlePost}
                    disabled={isPostButtonDisabled}
                  >
                    {posting ? "Posting..." : "Post"}
                  </Button>
                </div>
              </div>

              {postSuccess ? (
                <div className="flex flex-col items-center justify-center py-16">
                  <span className="text-gray-500 text-6xl mb-4">✓</span>
                  <span className="text-xl font-bold text-black dark:text-white">
                    Posted!
                  </span>
                </div>
              ) : (
                <div className="px-4">
                  {composerState.kind === "reply" && (
                    <div className="mb-1 -mx-4">
                      {isParentLoading ? (
                        <div className="text-sm text-gray-500 animate-pulse">
                          Loading parent post...
                        </div>
                      ) : parentUri ? (
                        <UniversalPostRendererATURILoader
                          atUri={parentUri}
                          bottomReplyLine
                          bottomBorder={false}
                        />
                      ) : (
                        <div className="text-sm text-red-500 rounded-lg border border-red-500/50 p-3">
                          Could not load parent post.
                        </div>
                      )}
                    </div>
                  )}

                  <div className="flex w-full gap-1 flex-col">
                    <ProfileThing agent={agent} large />
                    <div className="flex pl-[50px]">
                      <AutoGrowTextarea
                        className="w-full text-lg bg-transparent focus:outline-none resize-none placeholder:text-gray-500 text-black dark:text-white pb-2"
                        rows={5}
                        placeholder={getPlaceholder()}
                        value={postText}
                        onChange={(e) => setPostText(e.target.value)}
                        disabled={posting}
                        autoFocus
                      />
                    </div>
                  </div>

                  {composerState.kind === "quote" && (
                    <div className="mb-4 ml-[50px] rounded-lg border border-gray-200 dark:border-gray-700 overflow-hidden">
                      {isParentLoading ? (
                        <div className="text-sm text-gray-500 animate-pulse">
                          Loading parent post...
                        </div>
                      ) : parentUri ? (
                        <UniversalPostRendererATURILoader
                          atUri={parentUri}
                          isQuote
                        />
                      ) : (
                        <div className="text-sm text-red-500 rounded-lg border border-red-500/50 p-3">
                          Could not load parent post.
                        </div>
                      )}
                    </div>
                  )}

                  {postError && (
                    <div className="text-red-500 text-sm my-2 text-center">
                      {postError}
                    </div>
                  )}
                </div>
              )}
            </div>
          </Dialog.Content>
        </Dialog.Portal>
      </Dialog.Root>

      {/* Close confirmation dialog */}
      <Dialog.Root open={closeConfirmState} onOpenChange={setCloseConfirmState}>
        <Dialog.Portal>
          
          <Dialog.Overlay className="disablegutter fixed inset-0 z-50 bg-black/40 dark:bg-black/50 data-[state=open]:animate-fadeIn" />

          <Dialog.Content className="fixed gutter inset-0 z-50 flex items-start justify-center pt-30 sm:pt-40">
            <div className="bg-gray-50 dark:bg-gray-950 border border-gray-200 dark:border-gray-700 rounded-2xl shadow-xl w-full max-w-md relative mx-4 py-6">
              <div className="text-xl mb-4 text-center">
                Discard your post?
              </div>
              <div className="text-md mb-4 text-center">
                You will lose your draft
              </div>
              <div className="flex justify-end gap-2 px-6">
                <Button
                  onClick={handleConfirmClose}
                >
                  Discard
                </Button>
                <Button
                  variant={"outlined"}
                  onClick={() => setCloseConfirmState(false)}
                >
                  Cancel
                </Button>
              </div>
            </div>
          </Dialog.Content>
        </Dialog.Portal>
      </Dialog.Root>
    </>
  );
}

function AutoGrowTextarea({
  value,
  className,
  onChange,
  ...props
}: React.DetailedHTMLProps<
  React.TextareaHTMLAttributes<HTMLTextAreaElement>,
  HTMLTextAreaElement
>) {
  const ref = useRef<HTMLTextAreaElement>(null);

  useEffect(() => {
    const el = ref.current;
    if (!el) return;
    el.style.height = "auto";
    el.style.height = el.scrollHeight + "px";
  }, [value]);

  return (
    <textarea
      ref={ref}
      className={className}
      value={value}
      onChange={onChange}
      {...props}
    />
  );
}