import isMatch from "lodash/isMatch";
import type { Token } from "markdown-it";
import type {
  NodeSpec,
  Node as ProsemirrorNode,
  NodeType,
  Schema,
} from "prosemirror-model";
import type { Command } from "prosemirror-state";
import { NodeSelection, Plugin, TextSelection } from "prosemirror-state";
import type { Primitive } from "utility-types";
import { v4 as uuidv4 } from "uuid";
import env from "../../env";
import type { UnfurlResponse } from "../../types";
import { MentionType, UnfurlResourceType } from "../../types";
import {
  MentionCollection,
  MentionDocument,
  MentionGroup,
  MentionIssue,
  MentionPullRequest,
  MentionURL,
  MentionUser,
} from "../components/Mentions";
import type { MarkdownSerializerState } from "../lib/markdown/serializer";
import { transformListToMentions } from "../lib/mention";
import { findParentNodeClosestToPos } from "../queries/findParentNode";
import { isInList } from "../queries/isInList";
import { isList } from "../queries/isList";
import mentionRule from "../rules/mention";
import type { ComponentProps } from "../types";
import Node from "./Node";

export default class Mention extends Node {
  get name() {
    return "mention";
  }

  get schema(): NodeSpec {
    const toPlainText = (node: ProsemirrorNode) =>
      node.attrs.type === MentionType.User
        ? `@${node.attrs.label}`
        : node.attrs.label;

    return {
      attrs: {
        type: {
          default: MentionType.User,
        },
        label: {},
        modelId: {},
        actorId: {
          default: undefined,
        },
        id: {
          default: undefined,
        },
        href: {
          default: undefined,
        },
        unfurl: {
          default: undefined,
        },
      },
      inline: true,
      marks: "",
      group: "inline",
      atom: true,
      parseDOM: [
        {
          tag: `.${this.name}`,
          preserveWhitespace: "full",
          priority: 100,
          getAttrs: (dom: HTMLElement) => {
            const type = dom.dataset.type;
            const modelId = dom.dataset.id;
            if (!type || !modelId) {
              return false;
            }

            return {
              type,
              modelId,
              actorId: dom.dataset.actorid,
              label: dom.innerText,
              id: dom.id,
              href: dom.getAttribute("href"),
              unfurl: dom.dataset.unfurl
                ? JSON.parse(dom.dataset.unfurl)
                : undefined,
            };
          },
        },
      ],
      toDOM: (node) => [
        node.attrs.type === MentionType.User ? "span" : "a",
        {
          class: `${node.type.name} use-hover-preview`,
          id: node.attrs.id,
          href:
            node.attrs.type === MentionType.User
              ? undefined
              : node.attrs.type === MentionType.Document
                ? `${env.URL}/doc/${node.attrs.modelId}`
                : node.attrs.type === MentionType.Collection
                  ? `${env.URL}/collection/${node.attrs.modelId}`
                  : node.attrs.href,
          "data-type": node.attrs.type,
          "data-id": node.attrs.modelId,
          "data-actorid": node.attrs.actorId,
          "data-url":
            node.attrs.type === MentionType.PullRequest ||
            node.attrs.type === MentionType.Issue
              ? node.attrs.href
              : `mention://${node.attrs.id}/${node.attrs.type}/${node.attrs.modelId}`,
          "data-unfurl": JSON.stringify(node.attrs.unfurl),
        },
        toPlainText(node),
      ],
      leafText: toPlainText,
    };
  }

  component = (props: ComponentProps) => {
    switch (props.node.attrs.type) {
      case MentionType.User:
        return <MentionUser {...props} />;
      case MentionType.Group:
        return <MentionGroup {...props} />;
      case MentionType.Document:
        return <MentionDocument {...props} />;
      case MentionType.Collection:
        return <MentionCollection {...props} />;
      case MentionType.Issue:
        return (
          <MentionIssue
            {...props}
            onChangeUnfurl={this.handleChangeUnfurl(props)}
          />
        );
      case MentionType.PullRequest:
        return (
          <MentionPullRequest
            {...props}
            onChangeUnfurl={this.handleChangeUnfurl(props)}
          />
        );
      case MentionType.URL:
        return (
          <MentionURL
            {...props}
            onChangeUnfurl={this.handleChangeUnfurl(props)}
          />
        );
      default:
        return null;
    }
  };

  get rulePlugins() {
    return [mentionRule];
  }

  get plugins() {
    return [
      // Ensure mentions have unique IDs
      new Plugin({
        appendTransaction: (_transactions, _oldState, newState) => {
          const tr = newState.tr;
          const existingIds = new Set();
          let modified = false;

          tr.doc.descendants((node, pos) => {
            let nodeId = node.attrs.id;
            if (
              node.type.name === this.name &&
              (!nodeId || existingIds.has(nodeId))
            ) {
              nodeId = uuidv4();
              modified = true;
              tr.setNodeAttribute(pos, "id", nodeId);
            }
            existingIds.add(nodeId);
          });

          if (modified) {
            return tr;
          }

          return null;
        },
      }),
    ];
  }

  keys(): Record<string, Command> {
    const NavigableMention = [
      MentionType.Collection,
      MentionType.Document,
      MentionType.Issue,
      MentionType.PullRequest,
    ];

    return {
      Enter: (state) => {
        const { selection } = state;
        if (
          selection instanceof NodeSelection &&
          selection.node.type.name === this.name &&
          NavigableMention.includes(selection.node.attrs.type)
        ) {
          const mentionType = selection.node.attrs.type;

          let link: string;

          if (
            mentionType === MentionType.Issue ||
            mentionType === MentionType.PullRequest
          ) {
            link = selection.node.attrs.href;
          } else {
            const { modelId } = selection.node.attrs;

            const linkType =
              selection.node.attrs.type === MentionType.Document
                ? "doc"
                : "collection";

            link = `/${linkType}/${modelId}`;
          }

          this.editor.props.onClickLink?.(link);
          return true;
        }
        return false;
      },
    };
  }

  commands({ type }: { type: NodeType; schema: Schema }) {
    return {
      mention:
        (attrs: Record<string, Primitive>): Command =>
        (state, dispatch) => {
          const { selection } = state;
          const position =
            selection instanceof TextSelection
              ? selection.$cursor?.pos
              : selection.$to.pos;
          if (position === undefined) {
            return false;
          }

          const node = type.create(attrs);
          const transaction = state.tr.insert(position, node);
          dispatch?.(transaction);
          return true;
        },
      mention_list:
        (attrs: Record<string, Primitive>): Command =>
        (state, dispatch) => {
          const { selection } = state;
          const position =
            selection instanceof TextSelection
              ? selection.$cursor?.pos
              : selection.$to.pos;

          if (position === undefined || !isInList(state)) {
            return false;
          }

          const resolvedPos = state.tr.doc.resolve(position);
          const nodeWithPos = findParentNodeClosestToPos(resolvedPos, (node) =>
            isList(node, this.editor.schema)
          );

          if (!nodeWithPos) {
            return false;
          }

          const listNode = nodeWithPos.node,
            from = nodeWithPos.pos,
            to = from + listNode.nodeSize;

          const listNodeWithMentions = transformListToMentions(
            listNode,
            this.editor.schema,
            attrs
          );

          const tr = state.tr.deleteRange(from, to);
          dispatch?.(
            tr
              .setSelection(TextSelection.near(tr.doc.resolve(from)))
              .replaceSelectionWith(listNodeWithMentions)
          );

          return true;
        },
    };
  }

  toMarkdown(state: MarkdownSerializerState, node: ProsemirrorNode) {
    const mType = node.attrs.type;
    const mId = node.attrs.modelId;
    const label = node.attrs.label;
    const id = node.attrs.id;

    // Use regular links for document and collection mentions
    if (mType === MentionType.Document) {
      state.write(`[${label}](/doc/${mId})`);
    } else if (mType === MentionType.Collection) {
      state.write(`[${label}](/collection/${mId})`);
    } else {
      // Keep the existing mention:// format for other types (user, group, issue, pull_request, url)
      state.write(`@[${label}](mention://${id}/${mType}/${mId})`);
    }
  }

  parseMarkdown() {
    return {
      node: "mention",
      getAttrs: (tok: Token) => ({
        id: tok.attrGet("id"),
        type: tok.attrGet("type"),
        modelId: tok.attrGet("modelId"),
        label: tok.content,
      }),
    };
  }

  handleChangeUnfurl =
    ({ node, getPos }: { node: ProsemirrorNode; getPos: () => number }) =>
    (unfurl: UnfurlResponse[keyof UnfurlResponse]) => {
      const { view } = this.editor;
      const { tr } = view.state;

      const label =
        unfurl.type === UnfurlResourceType.Issue ||
        unfurl.type === UnfurlResourceType.PR ||
        unfurl.type === UnfurlResourceType.URL
          ? unfurl.title
          : undefined;

      const overrides: Record<string, unknown> = label ? { label } : {};
      overrides.unfurl = unfurl;

      const pos = getPos();

      if (!isMatch(node.attrs, overrides)) {
        const transaction = tr.setNodeMarkup(pos, undefined, {
          ...node.attrs,
          ...overrides,
        });
        view.dispatch(transaction);
      }
    };
}
