import { readFileSync, writeFileSync, mkdirSync } from "fs";
import { join } from "path";
import { createRequire } from "module";
import { getIconData, iconToSVG } from "@iconify/utils";

const require = createRequire(import.meta.url);
const ROOT = join(import.meta.dirname, "..");
const INVENTORY_FILE = join(ROOT, "src/generated/icon-inventory.json");
const OUT_DIR = join(ROOT, "src/generated");
const OUT_FILE = join(OUT_DIR, "site-icon-svgs.ts");

const PACKAGE_BY_PREFIX = {
    "fa6-brands": "@iconify-json/fa6-brands",
    "fa6-regular": "@iconify-json/fa6-regular",
    "fa6-solid": "@iconify-json/fa6-solid",
    mdi: "@iconify-json/mdi",
    "material-symbols": "@iconify-json/material-symbols",
    logos: "@iconify-json/logos",
    devicon: "@iconify-json/devicon",
    hugeicons: "@iconify-json/hugeicons",
    mingcute: "@iconify-json/mingcute",
    "skill-icons": "@iconify-json/skill-icons",
    "vscode-icons": "@iconify-json/vscode-icons",
    "material-icon-theme": "@iconify-json/material-icon-theme",
    "game-icons": "@iconify-json/game-icons",
    iconoir: "@iconify-json/iconoir",
};

function loadIconSet(prefix) {
    const pkg = PACKAGE_BY_PREFIX[prefix];
    if (!pkg) return null;
    return require(`${pkg}/icons.json`);
}

function buildSvg(iconName) {
    const [prefix, name] = iconName.split(":");
    const iconSet = loadIconSet(prefix);
    if (!iconSet) {
        console.warn(`Unknown icon set: ${prefix} (${iconName})`);
        return null;
    }
    const data = getIconData(iconSet, name);
    if (!data) {
        console.warn(`Icon not found: ${iconName}`);
        return null;
    }
    const { body, attributes } = iconToSVG(data, { height: "1em" });
    const attrs = Object.entries(attributes)
        .map(([k, v]) => `${k}="${v}"`)
        .join(" ");
    return `<svg xmlns="http://www.w3.org/2000/svg" ${attrs}>${body}</svg>`;
}

function main() {
    const inventory = JSON.parse(readFileSync(INVENTORY_FILE, "utf8"));
    /** @type {Record<string, string>} */
    const svgs = {};

    for (const [prefix, names] of Object.entries(inventory)) {
        for (const name of names) {
            const fullName = `${prefix}:${name}`;
            const svg = buildSvg(fullName);
            if (svg) svgs[fullName] = svg;
        }
    }

    const fallback =
        svgs["material-symbols:help-outline"] ??
        svgs["material-symbols:info"] ??
        Object.values(svgs)[0] ??
        "";

    const lines = [
        "// Generated by scripts/generate-site-icons.mjs — do not edit manually",
        "",
        `export const siteIconFallback = ${JSON.stringify(fallback)};`,
        "",
        "export const siteIconSvgs: Record<string, string> = {",
    ];

    for (const [name, svg] of Object.entries(svgs).sort(([a], [b]) => a.localeCompare(b))) {
        lines.push(`  ${JSON.stringify(name)}: ${JSON.stringify(svg)},`);
    }

    lines.push("};", "");

    mkdirSync(OUT_DIR, { recursive: true });
    writeFileSync(OUT_FILE, `${lines.join("\n")}\n`, "utf8");
    console.log(`Generated ${Object.keys(svgs).length} SVGs -> ${OUT_FILE}`);
}

main();