// @ts-check

/**
 * This script generates the src/protobufs directory from the proto files in the
 * repos specified in `REPOS`. It uses `buf` to generate TS files from the proto
 * files, and then generates an `index.ts` file to re-export the generated code.
 */

import { spawnSync } from "child_process";
import degit from "degit";
import { mkdirSync, readFileSync, rmSync, writeFileSync } from "fs";
import { globSync } from "glob";
import { capitalize } from "lodash-es";
import { dirname, join } from "path";
import { fileURLToPath } from "url";

/**
 * @typedef Repo
 * @type {object}
 * @property {string} repo - Git repo and branch to clone
 * @property {string[]} paths - Paths to proto files relative to the repo root
 */

/**
 * TODO: Add more repos here when necessary.
 * @type {Repo[]}
 */
const REPOS = [
  {
    repo: "cosmos/cosmos-sdk#v0.50.5",
    paths: ["proto"],
  },
  {
    repo: "cosmos/ics23#master",
    paths: ["proto"],
  },
  {
    repo: "cosmos/ibc-go#main",
    paths: ["proto"],
  },
  {
    repo: "onsonr/sonr#main",
    paths: ["proto"],
  },
  {
    repo: "CosmWasm/wasmd#main",
    paths: ["proto"],
  },
  {
    repo: "osmosis-labs/osmosis#main",
    paths: ["proto"],
  },
  {
    repo: "evmos/ethermint#main",
    paths: ["proto"],
  },
  {
    repo: "nomic-io/nomic#develop",
    paths: ["src/babylon/proto"],
  },
];

const __dirname = dirname(fileURLToPath(import.meta.url));
const PROTOBUFS_DIR = join(__dirname, "..", "src", "protobufs");
const TMP_DIR = join(PROTOBUFS_DIR, ".tmp");
/** Generates a unique dirname from `repo` to use in `TMP_DIR`. */
const id = (/** @type {string} */ repo) => repo.replace(/[#/]/g, "-");

console.log("Initialising directories...");
{
  rmSync(PROTOBUFS_DIR, { recursive: true, force: true });
  rmSync(TMP_DIR, { recursive: true, force: true });
  mkdirSync(PROTOBUFS_DIR);
  mkdirSync(TMP_DIR);
}

console.log("Cloning required repos...");
{
  await Promise.all(
    REPOS.map(({ repo }) => degit(repo).clone(join(TMP_DIR, id(repo))))
  );
}

console.log("Generating TS files from proto files...");
{
  for (const { repo, paths } of REPOS) {
    for (const path of paths) {
      spawnSync(
        "pnpm",
        [
          "buf",
          "generate",
          join(TMP_DIR, id(repo), path),
          "--output",
          join(
            PROTOBUFS_DIR,
            repo.startsWith("dymensionxyz") ? "dymension" : ""
          ),
        ],
        {
          cwd: process.cwd(),
          stdio: "inherit",
        }
      );
    }
    console.log(`✔️ [${repo}]`);
  }
}

console.log("Generating src/index.ts file and renaming exports...");
{
  const LAST_SEGMENT_REGEX = /[^/]+$/;
  const EXPORTED_NAME_REGEX = /^export \w+ (\w+) /gm;
  let contents =
    "/** This file is generated by gen-protobufs.mjs. Do not edit. */\n\n";
  /**
   * Builds the `src/proto/index.ts` file to re-export generated code.
   * A prefix is added to the exported names to avoid name collisions.
   * The prefix is the names of the directories in `proto` leading up
   * to the directory of the exported code, concatenated in PascalCase.
   * For example, if the exported code is in `proto/foo/bar/goo.ts`, the
   * prefix will be `FooBar`.
   * @param {string} dir
   */
  function generateIndexExports(dir) {
    const files = globSync(join(dir, "*"));
    if (files.length === 0) {
      return;
    }
    const prefixName = dir
      .replace(PROTOBUFS_DIR + "/", "")
      .split("/")
      .map((name) =>
        // convert all names to PascalCase
        name.split(/[-_]/).map(capitalize).join("")
      )
      .join("");
    for (const file of files) {
      const fileName = file.match(LAST_SEGMENT_REGEX)?.[0];
      if (!fileName) {
        console.error("Could not find name for", file);
        continue;
      }
      if (!fileName.endsWith(".ts")) {
        continue;
      }
      const code = readFileSync(file, "utf8");
      contents += `export {\n`;
      for (const match of code.matchAll(EXPORTED_NAME_REGEX)) {
        const exportedName = match[1];
        contents += `  ${exportedName} as ${prefixName + exportedName},\n`;
      }
      const exportedFile = file
        .replace(PROTOBUFS_DIR + "/", "")
        .replace(".ts", ".js");
      contents += `} from "./${exportedFile}";\n`;
    }
    for (const file of files) {
      generateIndexExports(file);
    }
  }
  generateIndexExports(PROTOBUFS_DIR);
  writeFileSync(join(PROTOBUFS_DIR, "index.ts"), contents);
}

console.log("Cleaning up...");
{
  rmSync(TMP_DIR, { recursive: true, force: true });
}

console.log("Proto generation completed successfully!");