/**
 * Bootstrap: downloads native binary for @matrix-org/matrix-sdk-crypto-nodejs
 * if it doesn't exist.
 *
 * This is needed because opencode's npm doesn't run postinstall scripts.
 * The binary is cached in the plugin's node_modules, so it only downloads once.
 *
 * Must be imported BEFORE any import from matrix-bot-sdk.
 */

import https from "https"
import fs from "fs"
import path from "path"

const CRYPTO_PACKAGE_DIR = path.join(
  __dirname,
  "..",
  "node_modules",
  "@matrix-org",
  "matrix-sdk-crypto-nodejs",
)

const VERSION = "0.4.0"

function isMusl(): boolean {
  if (!process.report || typeof process.report.getReport !== "function") {
    try {
      const lddPath = require("child_process")
        .execSync("which ldd")
        .toString()
        .trim()
      return fs.readFileSync(lddPath, "utf8").includes("musl")
    } catch {
      return true
    }
  }
  const { glibcVersionRuntime } = (process.report as any).getReport().header
  return !glibcVersionRuntime
}

function getBinaryName(): string {
  const platform = process.platform
  const arch = process.arch

  switch (platform) {
    case "linux":
      if (arch === "x64") {
        return isMusl()
          ? "matrix-sdk-crypto.linux-x64-musl.node"
          : "matrix-sdk-crypto.linux-x64-gnu.node"
      }
      if (arch === "arm64") {
        return isMusl()
          ? "matrix-sdk-crypto.linux-arm64-musl.node"
          : "matrix-sdk-crypto.linux-arm64-gnu.node"
      }
      if (arch === "arm") {
        return "matrix-sdk-crypto.linux-arm-gnueabihf.node"
      }
      if (arch === "s390x") {
        return "matrix-sdk-crypto.linux-s390x-gnu.node"
      }
      break
    case "darwin":
      if (arch === "x64") return "matrix-sdk-crypto.darwin-x64.node"
      if (arch === "arm64") return "matrix-sdk-crypto.darwin-arm64.node"
      break
    case "win32":
      if (arch === "x64") return "matrix-sdk-crypto.win32-x64-msvc.node"
      if (arch === "arm64") return "matrix-sdk-crypto.win32-arm64-msvc.node"
      break
  }

  throw new Error(
    `Unsupported platform: ${platform}-${arch}. ` +
      "matrix-bot-sdk requires a native crypto binary for this platform.",
  )
}

export function ensureNativeBinary(): void {
  const binaryName = getBinaryName()
  const binaryPath = path.join(CRYPTO_PACKAGE_DIR, binaryName)

  if (fs.existsSync(binaryPath)) {
    return // Already downloaded
  }

  const url = `https://github.com/matrix-org/matrix-rust-sdk-crypto-nodejs/releases/download/v${VERSION}/${binaryName}`
  const filePath = binaryPath

  console.error(`[matrix-plugin] Downloading native crypto binary: ${binaryName}`)

  https
    .get(url, (res) => {
      const statusCode = res.statusCode ?? 200
      if (statusCode >= 300 && statusCode < 400 && res.headers.location) {
        // Follow redirects
        https.get(res.headers.location, (redirectRes) => {
          const file = fs.createWriteStream(filePath)
          redirectRes.pipe(file)
          file.on("finish", () => {
            file.close()
            console.error(`[matrix-plugin] Native binary downloaded: ${binaryName}`)
          })
        }).on("error", (err) => {
          console.error(`[matrix-plugin] Failed to download native binary: ${err.message}`)
          console.error(`[matrix-plugin] Please ensure you have network access to GitHub releases.`)
        })
        return
      }

      const file = fs.createWriteStream(filePath)
      res.pipe(file)
      file.on("finish", () => {
        file.close()
        console.error(`[matrix-plugin] Native binary downloaded: ${binaryName}`)
      })
    })
    .on("error", (err) => {
      console.error(`[matrix-plugin] Failed to download native binary: ${err.message}`)
      console.error(`[matrix-plugin] Please ensure you have network access to GitHub releases.`)
    })
}