/**
 * main.ts — Plugin Entry (Effectful/Obsidian API)
 *
 * Registers the map viewer plugin, its custom view, commands,
 * ribbon icon, and workspace event handlers.
 */

import { Plugin, MarkdownView } from "obsidian";
import type { WorkspaceLeaf, TAbstractFile, TFile } from "obsidian";
import { VIEW_TYPE, MapViewerView } from "./mapView";

export default class MapViewerPlugin extends Plugin {
  private lastActiveFilePath: string | null = null;

  async onload(): Promise<void> {
    // Contract #1: Register view type with factory
    this.registerView(VIEW_TYPE, (leaf: WorkspaceLeaf) => {
      return new MapViewerView(leaf);
    });

    // Contract #2: Ribbon icon
    this.addRibbonIcon("map-pin", "Open map view", () => {
      this.activateView();
    });

    // Contract #3: Command
    this.addCommand({
      id: "open-map-view",
      name: "Open map view",
      callback: () => {
        this.activateView();
      },
    });

    // Contract #5: active-leaf-change event
    // NOTE: mapView.ts also registers this event for view-specific logic (e.g.,
    // clearMap on non-MarkdownView). Both handlers may fire; the view's debounce
    // in scheduleRefresh() collapses duplicate triggers. main.ts adds
    // lastActiveFilePath dedup to avoid unnecessary refresh calls.
    this.registerEvent(
      this.app.workspace.on("active-leaf-change", (leaf: WorkspaceLeaf | null) => {
        this.onActiveLeafChange(leaf);
      })
    );

    // Contract #6: vault modify event
    // NOTE: mapView.ts also registers this event with its own write-guard check.
    // Both handlers may fire; the view's debounce collapses duplicate triggers.
    this.registerEvent(
      this.app.vault.on("modify", (file: TAbstractFile) => {
        this.onFileModify(file as TFile);
      })
    );
  }

  onunload(): void {
    // Contract #7: Obsidian handles view deregistration automatically.
    // No special cleanup needed.
  }

  /**
   * Contract #4: Open the map view in the right sidebar as a singleton.
   */
  private async activateView(): Promise<void> {
    const leaves = this.app.workspace.getLeavesOfType(VIEW_TYPE);

    if (leaves.length > 0) {
      // Reveal existing leaf
      this.app.workspace.revealLeaf(leaves[0]);
      return;
    }

    // Create new leaf in right sidebar
    const leaf = this.app.workspace.getRightLeaf(false);
    if (!leaf) return;
    await leaf.setViewState({
      type: VIEW_TYPE,
      active: true,
    });
    this.app.workspace.revealLeaf(leaf);
  }

  /**
   * Contract #5: When active leaf changes, call the view's refresh()
   * if the new leaf is a MarkdownView and the file has changed.
   */
  private onActiveLeafChange(_leaf: WorkspaceLeaf | null): void {
    const mdView = this.app.workspace.getActiveViewOfType(MarkdownView);
    if (!mdView) return;

    // Dedup: skip if same file as last time
    const filePath = mdView.file?.path ?? null;
    if (filePath !== null && filePath === this.lastActiveFilePath) return;
    this.lastActiveFilePath = filePath;

    this.refreshMapView();
  }

  /**
   * Contract #6: When a file is modified, refresh the map view
   * if the modified file is the currently active file.
   */
  private onFileModify(file: TFile): void {
    const mdView = this.app.workspace.getActiveViewOfType(MarkdownView);
    if (!mdView?.file || mdView.file !== file) return;

    this.refreshMapView();
  }

  /**
   * Find the map-viewer view and call its refresh() method.
   */
  private refreshMapView(): void {
    const leaves = this.app.workspace.getLeavesOfType(VIEW_TYPE);
    if (leaves.length === 0) return;

    const view = leaves[0].view;
    if (view && typeof (view as MapViewerView).refresh === "function") {
      (view as MapViewerView).refresh();
    }
  }
}