import { readFileSync, readdirSync, statSync, writeFileSync, mkdirSync } from "fs";
import { join, relative } from "path";

const ROOT = join(import.meta.dirname, "..");
const SRC = join(ROOT, "src");
const OUT_DIR = join(SRC, "generated");
const OUT_FILE = join(OUT_DIR, "icon-inventory.json");
const OUT_INCLUDE = join(OUT_DIR, "icon-include.mjs");

/** @type {Record<string, string>} */
const ICON_ALIASES = {
    "eos-icons:loading": "material-symbols:progress-activity",
};

const KNOWN_PREFIXES = new Set([
    "material-symbols",
    "fa6-brands",
    "fa6-regular",
    "fa6-solid",
    "mdi",
    "logos",
    "devicon",
    "hugeicons",
    "mingcute",
    "skill-icons",
    "vscode-icons",
    "material-icon-theme",
    "game-icons",
    "iconoir",
]);

const ICON_PATTERN =
    /(?:name|icon)=["'{]([a-z0-9][a-z0-9-]*:[a-z0-9][a-z0-9._-]*)/gi;

const JSON_ICON_PATTERN = /"icon"\s*:\s*"([^"]+)"/g;
const YAML_ICON_PATTERN = /\bicon:\s*["']([^"']+)["']/g;
const TS_ICON_PATTERN = /\bicon\s*:\s*["']([^"']+)["']/g;
const RETURN_ICON_PATTERN =
    /return\s+["']([a-z0-9][a-z0-9-]*:[a-z0-9][a-z0-9._-]*)["']/g;

function walk(dir, files = []) {
    for (const entry of readdirSync(dir)) {
        const full = join(dir, entry);
        if (statSync(full).isDirectory()) {
            walk(full, files);
        } else {
            files.push(full);
        }
    }
    return files;
}

function normalizeIcon(name) {
    const trimmed = name.trim();
    return ICON_ALIASES[trimmed] ?? trimmed;
}

function addIcon(icons, raw) {
    const name = normalizeIcon(raw);
    if (!name.includes(":")) return;
    const [prefix, iconName] = name.split(":");
    if (!prefix || !iconName || !KNOWN_PREFIXES.has(prefix)) return;
    if (!icons[prefix]) icons[prefix] = new Set();
    icons[prefix].add(iconName);
}

function scanFile(path, icons) {
    const content = readFileSync(path, "utf8");
    const rel = relative(ROOT, path).replace(/\\/g, "/");

    if (rel.endsWith(".json")) {
        for (const match of content.matchAll(JSON_ICON_PATTERN)) {
            addIcon(icons, match[1]);
        }
        return;
    }

    if (rel.endsWith(".yaml") || rel.endsWith(".yml")) {
        for (const match of content.matchAll(YAML_ICON_PATTERN)) {
            addIcon(icons, match[1]);
        }
        return;
    }

    if (!/\.(astro|svelte|ts|tsx|js|mjs)$/.test(rel)) return;

    for (const match of content.matchAll(ICON_PATTERN)) {
        addIcon(icons, match[1]);
    }
    for (const match of content.matchAll(TS_ICON_PATTERN)) {
        addIcon(icons, match[1]);
    }
    for (const match of content.matchAll(RETURN_ICON_PATTERN)) {
        addIcon(icons, match[1]);
    }
}

function main() {
    /** @type {Record<string, Set<string>>} */
    const icons = {};

    const files = walk(SRC);
    for (const file of files) {
        if (file.includes("generated")) continue;
        scanFile(file, icons);
    }

    const extraConfigFiles = [join(ROOT, "twilight.config.yaml")];
    for (const file of extraConfigFiles) {
        try {
            scanFile(file, icons);
        } catch {
            /* optional config */
        }
    }

    /** @type {Record<string, string[]>} */
    const inventory = {};
    for (const [prefix, names] of Object.entries(icons)) {
        inventory[prefix] = [...names].sort();
    }

    mkdirSync(OUT_DIR, { recursive: true });
    writeFileSync(OUT_FILE, `${JSON.stringify(inventory, null, 2)}\n`, "utf8");
    writeFileSync(
        OUT_INCLUDE,
        `// AUTO-GENERATED by scripts/collect-icons.mjs — do not edit\nexport default ${JSON.stringify(inventory, null, 4)};\n`,
        "utf8",
    );

    const total = Object.values(inventory).reduce((n, arr) => n + arr.length, 0);
    console.log(`Collected ${total} icons in ${Object.keys(inventory).length} sets -> ${relative(ROOT, OUT_FILE)}`);
}

main();