// Copyright (c) 2009-2017 The OTS Authors. All rights reserved.

// Use of this source code is governed by a BSD-style license that can be

// found in the LICENSE file.

#include "gloc.h"

#include "name.h"

namespace ots {

bool OpenTypeGLOC::Parse(const uint8_t* data, size_t length) {

  Buffer table(data, length);

  OpenTypeNAME* name = static_cast<OpenTypeNAME*>(

      GetFont()->GetTypedTable(OTS_TAG_NAME));

  if (!name) {

    return DropGraphite("Required name table is missing");

  }

  if (!table.ReadU32(&this->version)) {

    return DropGraphite("Failed to read version");

  }

  if (this->version >> 16 != 1) {

    return DropGraphite("Unsupported table version: %u", this->version >> 16);

  }

  if (!table.ReadU16(&this->flags) || this->flags > 0b11) {

    return DropGraphite("Failed to read valid flags");

  }

  if (!table.ReadU16(&this->numAttribs)) {

    return DropGraphite("Failed to read numAttribs");

  }

  if (this->flags & ATTRIB_IDS && this->numAttribs * sizeof(uint16_t) >

                                  table.remaining()) {

    return DropGraphite("Failed to calculate length of locations");

  }

  size_t locations_len = (table.remaining() -

    (this->flags & ATTRIB_IDS ? this->numAttribs * sizeof(uint16_t) : 0)) /

    (this->flags & LONG_FORMAT ? sizeof(uint32_t) : sizeof(uint16_t));

  //this->locations.resize(locations_len);

  if (this->flags & LONG_FORMAT) {

    unsigned long last_location = 0;

    for (size_t i = 0; i < locations_len; ++i) {

      this->locations.emplace_back();

      uint32_t& location = this->locations[i];

      if (!table.ReadU32(&location) || location < last_location) {

        return DropGraphite("Failed to read valid locations[%lu]", i);

      }

      last_location = location;

    }

  } else {  // short (16-bit) offsets

    unsigned last_location = 0;

    for (size_t i = 0; i < locations_len; ++i) {

      uint16_t location;

      if (!table.ReadU16(&location) || location < last_location) {

        return DropGraphite("Failed to read valid locations[%lu]", i);

      }

      last_location = location;

      this->locations.push_back(static_cast<uint32_t>(location));

    }

  }

  if (this->locations.empty()) {

    return DropGraphite("No locations");

  }

  if (this->flags & ATTRIB_IDS) {  // attribIds array present

    //this->attribIds.resize(numAttribs);

    for (unsigned i = 0; i < this->numAttribs; ++i) {

      this->attribIds.emplace_back();

      if (!table.ReadU16(&this->attribIds[i]) ||

          !name->IsValidNameId(this->attribIds[i])) {

        return DropGraphite("Failed to read valid attribIds[%u]", i);

      }

    }

  }

  if (table.remaining()) {

    return Warning("%zu bytes unparsed", table.remaining());

  }

  return true;

}

bool OpenTypeGLOC::Serialize(OTSStream* out) {

  if (!out->WriteU32(this->version) ||

      !out->WriteU16(this->flags) ||

      !out->WriteU16(this->numAttribs) ||

      (this->flags & LONG_FORMAT ? !SerializeParts(this->locations, out) :

       ![&] {

         for (uint32_t location : this->locations) {

           if (!out->WriteU16(static_cast<uint16_t>(location))) {

             return false;

           }

         }

         return true;

       }()) ||

      (this->flags & ATTRIB_IDS && !SerializeParts(this->attribIds, out))) {

    return Error("Failed to write table");

  }

  return true;

}

const std::vector<uint32_t>& OpenTypeGLOC::GetLocations() {

  return this->locations;

}

}  // namespace ots