package org.matrix.chromext.script

import android.content.Context
import android.net.Uri
import java.io.File
import java.io.FileReader
import kotlin.random.Random
import org.json.JSONArray
import org.json.JSONObject
import org.matrix.chromext.Chrome
import org.matrix.chromext.Resource
import org.matrix.chromext.utils.Log
import org.matrix.chromext.utils.randomString

object GM {
  private val localScript: Map<String, String>

  init {
    val ctx = Chrome.getContext()
    Resource.enrich(ctx)
    localScript =
        ctx.assets
            .open("GM.js")
            .bufferedReader()
            .use { it.readText() }
            .split("// Kotlin separator\n\n")
            .associateBy(
                {
                  val decalre = it.lines()[0]
                  val sep = if (decalre.startsWith("function")) "(" else " ="
                  decalre.split(sep)[0].split(" ").last()
                },
                { it })
  }

  fun bootstrap(
      script: Script,
      codes: MutableList<String> = mutableListOf<String>(),
  ): MutableList<String> {
    var code = script.code
    var grants = ""

    if (!script.meta.startsWith("// ==UserScript==")) {
      code = script.meta + code
    }

    script.grant.forEach {
      when (it) {
        "none" -> return@forEach
        "frames" -> return@forEach
        "GM_info" -> return@forEach
        "GM.ChromeXt" -> return@forEach
        "window.close" -> return@forEach
        else ->
            if (localScript.containsKey(it)) {
              grants += localScript.get(it)
            } else if (it.startsWith("GM_")) {
              grants +=
                  "function ${it}(){ console.error('${it} is not implemented in ChromeXt yet, called with', arguments) }\n"
            } else if (it.startsWith("GM.")) {
              val func = it.substring(3)
              val name =
                  "GM_" +
                      if (func == "xmlHttpRequest") {
                        "xmlhttpRequest"
                      } else if (func == "getResourceUrl") {
                        "getResourceURL"
                      } else {
                        func
                      }
              if (localScript.containsKey(name) && !script.grant.contains(name))
                  grants += localScript.get(name)
              grants += "${it}={sync: ${name}};\n"
            }
      }
    }

    grants += localScript.get("GM.bootstrap")!!
    val GM_info = JSONObject(mapOf("scriptMetaStr" to script.meta))
    GM_info.put("script", JSONObject().put("id", script.id))
    if (script.storage != null) GM_info.put("storage", script.storage)
    code = "\ndelete window.__loading__;\n${code};"
    code = localScript.get("globalThis")!! + script.lib.joinToString("\n") + code
    codes.add(
        "(()=>{ const GM = {key:${Local.key}, name:'${Local.name}'}; const GM_info = ${GM_info}; GM_info.script.code = (key=null) => {${code}};\n${grants}GM.bootstrap();})();\n//# sourceURL=local://ChromeXt/${Uri.encode(script.id)}")
    return codes
  }
}

object Local {

  val promptInstallUserScript: String
  val customizeDevTool: String
  val eruda: String
  val encoding: String
  val initChromeXt: String
  val openEruda: String
  val cspRule: String
  val cosmeticFilter: String
  val key = Random.nextDouble()
  val name = randomString(25)

  var eruda_version: String?

  val anchorInChromeXt: Int

  // lineNumber of the anchor in GM.js, used to verify ChromeXt.dispatch

  init {
    val ctx = Chrome.getContext()
    Resource.enrich(ctx)
    var css =
        JSONArray(
            ctx.assets.open("editor.css").bufferedReader().use { it.readText() }.split("\n\n"))
    promptInstallUserScript =
        "const _editor_style = ${css}[0];\n" +
            ctx.assets.open("editor.js").bufferedReader().use { it.readText() }
    customizeDevTool = ctx.assets.open("devtools.js").bufferedReader().use { it.readText() }
    css =
        JSONArray(ctx.assets.open("eruda.css").bufferedReader().use { it.readText() }.split("\n\n"))
    eruda =
        "eruda._styles = ${css};\n" +
            ctx.assets
                .open("eruda.js")
                .bufferedReader()
                .use { it.readText() }
                .replaceFirst("Symbol.ChromeXt", "Symbol." + name)
                .replaceFirst("ChromeXtUnlockKeyForEruda", key.toString())
    encoding = ctx.assets.open("encoding.js").bufferedReader().use { it.readText() }
    eruda_version = getErudaVersion()
    val localScript =
        ctx.assets
            .open("scripts.js")
            .bufferedReader()
            .use { it.readText() }
            .split("// Kotlin separator\n\n")

    val seed = Random.nextDouble()
    // Use empty lines to randomize anchorInChromeXt
    val parts =
        localScript[0]
            .replaceFirst("Symbol.ChromeXt", "Symbol." + name)
            .replaceFirst("ChromeXtUnlockKeyForInit", key.toString())
            .split("\n")
            .filter { if (it.length != 0) true else Random.nextDouble() > seed }
    anchorInChromeXt = parts.indexOfFirst { it.endsWith("// Kotlin anchor") } + 2
    initChromeXt = parts.joinToString("\n")
    openEruda =
        localScript[1]
            .replaceFirst("Symbol.ChromeXt", "Symbol." + name)
            .replaceFirst("ChromeXtUnlockKeyForEruda", key.toString())
    cspRule = localScript[2]
    cosmeticFilter = localScript[3]
  }

  fun getErudaVersion(ctx: Context = Chrome.getContext(), versionText: String? = null): String? {
    val eruda = File(ctx.filesDir, "Eruda.js")
    if (eruda.exists() || versionText != null) {
      val verisonReg = Regex(" eruda v(?<version>[\\d\\.]+) https://")
      val firstLine = (versionText ?: FileReader(eruda).use { it.readText() }).lines()[0]
      val vMatchGroup = verisonReg.find(firstLine)?.groups
      if (vMatchGroup != null) {
        return vMatchGroup[1]?.value as String
      } else if (eruda.exists()) {
        eruda.delete()
        Log.toast(ctx, "Eruda.js is corrupted")
      }
    }
    return null
  }
}