export default class ESP8266ROM {
  static CHIP_NAME = "ESP8266";
  static CHIP_DETECT_MAGIC_VALUE = [0xfff0c101];
  static EFUSE_RD_REG_BASE = 0x3ff00050;
  static UART_CLKDIV_REG = 0x60000014;
  static UART_CLKDIV_MASK = 0xFFFFF;
  static XTAL_CLK_DIVIDER = 2;

  static FLASH_WRITE_SIZE = 0x4000;
  static BOOTLOADER_FLASH_OFFSET = 0;

  static FLASH_SIZES = {
    '512KB': 0x00,
    '256KB': 0x10,
    '1MB': 0x20,
    '2MB': 0x30,
    '4MB': 0x40,
    '2MB-c1': 0x50,
    '4MB-c1': 0x60,
    '8MB': 0x80,
    '16MB': 0x90
  };

  static SPI_REG_BASE    = 0x60000200;
  static SPI_USR_OFFS    = 0x1c;
  static SPI_USR1_OFFS   = 0x20;
  static SPI_USR2_OFFS   = 0x24;
  static SPI_MOSI_DLEN_OFFS = null;
  static SPI_MISO_DLEN_OFFS = null;
  static SPI_W0_OFFS     = 0x40;

  static TEXT_START = 0x4010e000;
  static ENTRY = 0x4010e004;
  static DATA_START = 0x3fffaca8;
  static ROM_DATA =
    "" +
    "CIH+PwUFBAACAwcAAwMLAFHnEECH5xBAtecQQFToEEAF9xBAuugQQBDpEEBc6RBA" +
    "BfcQQCLqEECf6hBAYOsQQAX3EEAF9xBA+OsQQAX3EEDX7hBAn+8QQNjvEEAF9xBA" +
    "BfcQQHXwEEAF9xBAW/EQQAHyEEBA8xBA//MQQND0EEAF9xBABfcQQAX3EEAF9xBA" +
    "/vUQQAX3EED09hBAL+0QQCfoEEBC9RBAS+oQQJjpEEAF9xBAiPYQQM/2EEAF9xBA" +
    "BfcQQAX3EEAF9xBABfcQQAX3EEAF9xBABfcQQMDpEED/6RBAWvUQQAEAAAACAAAA" +
    "AwAAAAQAAAAFAAAABwAAAAkAAAANAAAAEQAAABkAAAAhAAAAMQAAAEEAAABhAAAA" +
    "gQAAAMEAAAABAQAAgQEAAAECAAABAwAAAQQAAAEGAAABCAAAAQwAAAEQAAABGAAA" +
    "ASAAAAEwAAABQAAAAWAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAEAAAABAAAA" +
    "AgAAAAIAAAADAAAAAwAAAAQAAAAEAAAABQAAAAUAAAAGAAAABgAAAAcAAAAHAAAA" +
    "CAAAAAgAAAAJAAAACQAAAAoAAAAKAAAACwAAAAsAAAAMAAAADAAAAA0AAAANAAAA" +
    "AAAAAAAAAAADAAAABAAAAAUAAAAGAAAABwAAAAgAAAAJAAAACgAAAAsAAAANAAAA" +
    "DwAAABEAAAATAAAAFwAAABsAAAAfAAAAIwAAACsAAAAzAAAAOwAAAEMAAABTAAAA" +
    "YwAAAHMAAACDAAAAowAAAMMAAADjAAAAAgEAAAAAAAAAAAAAAAAAAAAAAAAAAAAA" +
    "AAAAAAAAAAAAAAAAAAAAAAAAAAABAAAAAQAAAAEAAAABAAAAAgAAAAIAAAACAAAA" +
    "AgAAAAMAAAADAAAAAwAAAAMAAAAEAAAABAAAAAQAAAAEAAAABQAAAAUAAAAFAAAA" +
    "BQAAAAAAAAAAAAAAAAAAABAREgAIBwkGCgULBAwDDQIOAQ8AAQEAAAEAAAAEAAAA";
  static ROM_TEXT =
    "" +
    "H4sIAE9Bw2ICA41ZC1gTV74/M0kGLAMkQVmXpHXmgOQhqZmJClhYkgARH7SKn1R3" +
    "110Gd6PXT7aKdrG9eEtBo9uytzyqtX5uN6DX9tp25dO+7ra9jVgi9uLWR6+rVVqk" +
    "L/WuGtHyCCTn/mfiq3b33ub7TiZz5v//n9//ef5n8ooWOSlCPOsQQk1Pk4J4ihTU" +
    "1SG0EYbTiVCJixQ8D/PCCNEfDHHcOlpSbfqGEvdFt1WrFtwgrkEi3CAwb59eN2dR" +
    "gEMrVO4JyGm/YSh0Om/AvXsRmjkDrrgQ4QlI+B+gvZHdUsB/TYSviesimSkqTAu+" +
    "JqZteh+SPzBhUcPXEpWHlm+WyDcWlXCWzMSsCn6LZShe0B/UJoaQPxGh7YAPPR0t" +
    "eKTENfuV10jBbhjmPq3zbyNaJ4tQBSEgVCtLppSvRtBN65R/whP5CrxqGFoTQuMV" +
    "+mQky4mHuXfgioA+xwL2eQ7mGkiBFsZrML9zHymw/4EUbIHrdgPIiQfmcQjNT4Kh" +
    "RygPeDqA7g0Yn+wlBQ/BfQiwskDf9CewcwLggGvT66RAQQafjgkIXQO824FnO/C8" +
    "l4ycW2C8AmNxAXIWeZAzax5yri8B5HOQ843ZyNnzIHKezkXOks+Rs+k8cs7LRM6N" +
    "MM+/R1ratE26AJbSsR/RUmGn5D4hufol54BUQF0kAYT4/UQ4QFg1AwBm03Nxtjjc" +
    "9TqF/Y1soZUv9lNdr1F8LTn4JBFeJdYssP0Rmn8F6HNpAS5l1BlZiLCH4DYKHpao" +
    "uAxOcRb2c9RJ+Rl14s73mj+QBS8R10tEeIlUtiGWpo4qGHYSoZJY04Exh05dS+B6" +
    "mlYcnUuzeuzaiBMpNgO7NrkXFIoSzmwZZ3Rk6zkfmBvhRJWYSNdhnR1zXrfObAMu" +
    "M40lDAoZMV5Q2OUHbTamYbZhUysF1AMKdWiA458iQ/tTsD9Q/K9AcaXr95TmJcpz" +
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    "+PdXUUSdh29EO/v6mvG+Ya5HO+BHqTsZH/t3sC9jviEgc2mCArvvOwJB3LM9bzV+" +
    "yX8V6ewZDov8WMSaDgnfd8GlyGqRXdukuHZaQ5WKXRv8JCYLwPGnIy+/3+u6GhET" +
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    "/5RlV/MOEBxbIT8O+5vc/nh34eIEbHCUlxHsXy36x4mzLsB9Ddwbn69uW9xcFWHX" +
    "g3HQk3gHrncjm8ogzmq9xtdHhPoIuxFywQ3Ow9ktQ74Kin8qEsZgalPe/R7ZP+2y" +
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    "tEs2LD1YKisHbo35N6hCOHmxgWixX8Q6A8DRifyDzqmBbPFrlrboLNTrNJvSV6hr" +
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    "U8dsHLVTwfIRudST5l3M8FtJGvS7pvfeFw6R+VmBNGi4sqEh/Yz4LhG3H7lLV/F/" +
    "JlpcRwWUv31oIv2Z4MRVWm9dDlMch4b6dYMPJ7n2w3qXpuFCZLgSvEbEfdHsloOZ" +
    "D1v4DeRYPidz18ncxRcIv17xUtenZNM3YC7qv4blGqxB0lpSZktTjPNm96N5NHOG" +
    "BK8S1Nz2fQcupd3+gFk1a2tSj8jqoa9laYuqtj8xlKnXZGJdMAG5/WdtmllbLSy2" +
    "qKBzhSA3bY1n9RaVTQ2edvt7awdmbU2QJyARYKZ2QA6At9LtVfT8QafzunPWm5b5" +
    "RQE0Xn5Dx9LZM9R2b8CAQ9BCCK6EovIPo9kzKAMGpsbWxFD2DJbVKxGEUNHscjtL" +
    "J4beSjfPH4hJ+tFtSdkibccBEOH+kJSrSew2MdSz8C5GWch459cfjuMcT0Pvo0yI" +
    "bcqT/wWthFLmqB8AAA==";

  static read_efuse = async (loader, offset) => {
      var addr = this.EFUSE_RD_REG_BASE + (4 * offset);
      console.log("Read efuse " + addr);
      return await loader.read_reg({addr: addr});
  }

  static get_chip_description = async (loader) => {
      var efuse3 = await this.read_efuse(loader, 2);
      var efuse0 = await this.read_efuse(loader, 0);

      var is_8285 = ((efuse0 & (1 << 4)) | (efuse3 & (1 << 16))) != 0;  // One or the other efuse bit is set for ESP8285
      return is_8285 ? "ESP8285" : "ESP8266EX";
  }

  static get_chip_features = async (loader) => {
      var features = ["WiFi"]
      if (await this.get_chip_description(loader) == "ESP8285")
          features.push("Embedded Flash");
      return features;
  }

  static get_crystal_freq = async (loader) => {
      var uart_div = await loader.read_reg({addr: this.UART_CLKDIV_REG}) & this.UART_CLKDIV_MASK;
      var ets_xtal = (loader.transport.baudrate * uart_div) / 1000000 / this.XTAL_CLK_DIVIDER;
      var norm_xtal;
      if (ets_xtal > 33) {
          norm_xtal = 40;
      } else {
          norm_xtal = 26;
      }
      if (Math.abs(norm_xtal - ets_xtal) > 1) {
          loader.log("WARNING: Detected crystal freq " + ets_xtal + "MHz is quite different to normalized freq " + norm_xtal + "MHz. Unsupported crystal in use?");
      }
      return norm_xtal;
  }

  static _d2h(d) {
      var h = (+d).toString(16);
      return h.length === 1 ? '0' + h: h;
  }

  static read_mac = async (loader) => {
      var mac0 = await this.read_efuse(loader, 0);
      mac0 = mac0 >>> 0;
      var mac1 = await this.read_efuse(loader, 1);
      mac1 = mac1 >>> 0;
      var mac3 = await this.read_efuse(loader, 3);
      mac3 = mac3 >>> 0;
      var mac = new Uint8Array(6);

      if (mac3 != 0) {
          mac[0] = (mac3 >> 16) & 0xff;
          mac[1] = (mac3 >> 8) & 0xff;
          mac[2] = mac3 & 0xff;
      }
      else if (((mac1 >> 16) & 0xff) == 0) {
          mac[0] = 0x18;
          mac[1] = 0xfe;
          mac[2] = 0x34;
      }
      else if (((mac1 >> 16) & 0xff) == 1) {
          mac[0] = 0xac;
          mac[1] = 0xd0;
          mac[2] = 0x74;
      }
      else {
          loader.log("Unknown OUI");
      }

      mac[3] = (mac1 >> 8) & 0xff;
      mac[4] = mac1 & 0xff;
      mac[5] = (mac0 >> 24) & 0xff;

      return(this._d2h(mac[0])+":"+this._d2h(mac[1])+":"+this._d2h(mac[2])+":"+this._d2h(mac[3])+":"+this._d2h(mac[4])+":"+this._d2h(mac[5]));
  }

  static get_erase_size = function(offset, size) {
      return size;
  }
}