import path from "path";
import fs from "fs";
import type { HiddenSubtreeItem } from "./hidden_subtree.js";
import type NoteMeta from "./meta/note_meta.js";
import type { NoteMetaFile } from "./meta/note_meta.js";
import { fileURLToPath } from "url";
import { isDev } from "./utils.js";

export function getHelpHiddenSubtreeData() {
    const srcRoot = path.join(path.dirname(fileURLToPath(import.meta.url)), "..");
    const appDir = path.join(srcRoot, "public", isDev ? "app" : "app-dist");
    const helpDir = path.join(appDir, "doc_notes", "en", "User Guide");
    const metaFilePath = path.join(helpDir, "!!!meta.json");
    const metaFileContent = JSON.parse(fs.readFileSync(metaFilePath).toString("utf-8"));

    try {
        return parseNoteMetaFile(metaFileContent as NoteMetaFile);
    } catch (e) {
        console.warn(e);
        return [];
    }
}

function parseNoteMetaFile(noteMetaFile: NoteMetaFile): HiddenSubtreeItem[] {
    if (!noteMetaFile.files) {
        return [];
    }

    const metaRoot = noteMetaFile.files[0];
    const parsedMetaRoot = parseNoteMeta(metaRoot, "/" + (metaRoot.dirFileName ?? ""));
    return parsedMetaRoot.children ?? [];
}

function parseNoteMeta(noteMeta: NoteMeta, docNameRoot: string): HiddenSubtreeItem {
    let iconClass: string = "bx bx-file";
    const item: HiddenSubtreeItem = {
        id: `_help_${noteMeta.noteId}`,
        title: noteMeta.title ?? "",
        type: "doc", // can change
        attributes: []
    };

    // Handle attributes
    for (const attribute of noteMeta.attributes ?? []) {
        if (attribute.name === "iconClass") {
            iconClass = attribute.value;
        }
    }

    // Handle folder notes
    if (!noteMeta.dataFileName) {
        iconClass = "bx bx-folder";
        item.type = "book";
    }

    // Handle text notes
    if (noteMeta.type === "text" && noteMeta.dataFileName) {
        const docPath = `${docNameRoot}/${path.basename(noteMeta.dataFileName, ".html")}`
            .substring(1);
        item.attributes?.push({
            type: "label",
            name: "docName",
            value: docPath
        });
    }

    // Handle children
    if (noteMeta.children) {
        const children: HiddenSubtreeItem[] = [];
        for (const childMeta of noteMeta.children) {
            let newDocNameRoot = (noteMeta.dirFileName ? `${docNameRoot}/${noteMeta.dirFileName}` : docNameRoot);
            children.push(parseNoteMeta(childMeta, newDocNameRoot));
        }

        item.children = children;
    }

    // Handle note icon
    item.attributes?.push({
        name: "iconClass",
        value: iconClass,
        type: "label"
    });

    return item;
}