// Copyright 2016 The Chromium Authors
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

#include "cert_errors.h"

#include "cert_error_params.h"
#include "parse_name.h"
#include "parsed_certificate.h"

#include <sstream>

BSSL_NAMESPACE_BEGIN

namespace {

void AppendLinesWithIndentation(const std::string &text,
                                const std::string &indentation,
                                std::string *out) {
  std::istringstream stream(text);
  for (std::string line; std::getline(stream, line, '\n');) {
    out->append(indentation);
    out->append(line);
    out->append("\n");
  }
}

}  // namespace

CertError::CertError() = default;

CertError::CertError(Severity in_severity, CertErrorId in_id,
                     std::unique_ptr<CertErrorParams> in_params)
    : severity(in_severity), id(in_id), params(std::move(in_params)) {}

CertError::CertError(CertError &&other) = default;

CertError &CertError::operator=(CertError &&) = default;

CertError::~CertError() = default;

std::string CertError::ToDebugString() const {
  std::string result;
  switch (severity) {
    case SEVERITY_WARNING:
      result += "WARNING: ";
      break;
    case SEVERITY_HIGH:
      result += "ERROR: ";
      break;
  }
  result += CertErrorIdToDebugString(id);
  result += +"\n";

  if (params) {
    AppendLinesWithIndentation(params->ToDebugString(), "  ", &result);
  }

  return result;
}

CertErrors::CertErrors() = default;
CertErrors::CertErrors(CertErrors &&other) = default;
CertErrors &CertErrors::operator=(CertErrors &&) = default;
CertErrors::~CertErrors() = default;

void CertErrors::Add(CertError::Severity severity, CertErrorId id,
                     std::unique_ptr<CertErrorParams> params) {
  nodes_.emplace_back(severity, id, std::move(params));
}

void CertErrors::AddError(CertErrorId id,
                          std::unique_ptr<CertErrorParams> params) {
  Add(CertError::SEVERITY_HIGH, id, std::move(params));
}

void CertErrors::AddError(CertErrorId id) { AddError(id, nullptr); }

void CertErrors::AddWarning(CertErrorId id,
                            std::unique_ptr<CertErrorParams> params) {
  Add(CertError::SEVERITY_WARNING, id, std::move(params));
}

void CertErrors::AddWarning(CertErrorId id) { AddWarning(id, nullptr); }

std::string CertErrors::ToDebugString() const {
  std::string result;
  for (const CertError &node : nodes_) {
    result += node.ToDebugString();
  }

  return result;
}

bool CertErrors::ContainsErrorWithSeverity(CertErrorId id,
                                           CertError::Severity severity) const {
  for (const CertError &node : nodes_) {
    if (node.id == id && node.severity == severity) {
      return true;
    }
  }
  return false;
}

bool CertErrors::ContainsError(CertErrorId id) const {
  return ContainsErrorWithSeverity(id, CertError::SEVERITY_HIGH);
}

bool CertErrors::ContainsAnyErrorWithSeverity(
    CertError::Severity severity) const {
  for (const CertError &node : nodes_) {
    if (node.severity == severity) {
      return true;
    }
  }
  return false;
}

CertPathErrors::CertPathErrors() = default;

CertPathErrors::CertPathErrors(CertPathErrors &&other) = default;
CertPathErrors &CertPathErrors::operator=(CertPathErrors &&) = default;

CertPathErrors::~CertPathErrors() = default;

CertErrors *CertPathErrors::GetErrorsForCert(size_t cert_index) {
  if (cert_index >= cert_errors_.size()) {
    cert_errors_.resize(cert_index + 1);
  }
  return &cert_errors_[cert_index];
}

const CertErrors *CertPathErrors::GetErrorsForCert(size_t cert_index) const {
  if (cert_index >= cert_errors_.size()) {
    return nullptr;
  }
  return &cert_errors_[cert_index];
}

CertErrors *CertPathErrors::GetOtherErrors() { return &other_errors_; }

const CertErrors *CertPathErrors::GetOtherErrors() const {
  return &other_errors_;
}

bool CertPathErrors::ContainsError(CertErrorId id) const {
  for (const CertErrors &errors : cert_errors_) {
    if (errors.ContainsError(id)) {
      return true;
    }
  }

  if (other_errors_.ContainsError(id)) {
    return true;
  }

  return false;
}

bool CertPathErrors::ContainsAnyErrorWithSeverity(
    CertError::Severity severity) const {
  for (const CertErrors &errors : cert_errors_) {
    if (errors.ContainsAnyErrorWithSeverity(severity)) {
      return true;
    }
  }

  if (other_errors_.ContainsAnyErrorWithSeverity(severity)) {
    return true;
  }

  return false;
}

std::optional<CertErrorId> CertPathErrors::FindSingleHighSeverityError(
    ptrdiff_t &out_depth) const {
  std::optional<CertErrorId> id_seen;
  for (ptrdiff_t i = -1; i < (ptrdiff_t)cert_errors_.size(); ++i) {
    const CertErrors *errors =
        (i < 0) ? GetOtherErrors() : GetErrorsForCert(i);
    for (const CertError &node : errors->nodes_) {
      if (node.severity == CertError::SEVERITY_HIGH) {
        if (!id_seen.has_value()) {
          id_seen = node.id;
          out_depth = i;
        } else {
          if (id_seen.value() != node.id) {
            return {};
          }
        }
      }
    }
  }
  return id_seen;
}

std::string CertPathErrors::ToDebugString(
    const ParsedCertificateList &certs) const {
  std::ostringstream result;

  for (size_t i = 0; i < cert_errors_.size(); ++i) {
    // Pretty print the current CertErrors. If there were no errors/warnings,
    // then continue.
    const CertErrors &errors = cert_errors_[i];
    std::string cert_errors_string = errors.ToDebugString();
    if (cert_errors_string.empty()) {
      continue;
    }

    // Add a header that identifies which certificate this CertErrors pertains
    // to.
    std::string cert_name_debug_str;
    if (i < certs.size() && certs[i]) {
      RDNSequence subject;
      if (ParseName(certs[i]->tbs().subject_tlv, &subject) &&
          ConvertToRFC2253(subject, &cert_name_debug_str)) {
        cert_name_debug_str = " (" + cert_name_debug_str + ")";
      }
    }
    result << "----- Certificate i=" << i << cert_name_debug_str << " -----\n";
    result << cert_errors_string << "\n";
  }

  // Print any other errors that aren't associated with a particular certificate
  // in the chain.
  std::string other_errors = other_errors_.ToDebugString();
  if (!other_errors.empty()) {
    result << "----- Other errors (not certificate specific) -----\n";
    result << other_errors << "\n";
  }

  return result.str();
}

BSSL_NAMESPACE_END