// Copyright 2014 The Chromium 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 "chrome/browser/extensions/extension_management_internal.h"

#include <utility>

#include "base/logging.h"
#include "base/values.h"
#include "base/version.h"
#include "chrome/browser/extensions/extension_management_constants.h"
#include "extensions/common/url_pattern_set.h"
#include "url/gurl.h"

namespace extensions {

namespace internal {

namespace {
const char kMalformedPreferenceWarning[] =
    "Malformed extension management preference.";

// Maximum number of characters for a 'blocked_install_message' value.
const int kBlockedInstallMessageMaxLength = 1000;
}  // namespace

IndividualSettings::IndividualSettings() {
  Reset();
}

// Initializes from default settings.
IndividualSettings::IndividualSettings(
    const IndividualSettings* default_settings) {
  installation_mode = default_settings->installation_mode;
  update_url = default_settings->installation_mode;
  blocked_permissions = default_settings->blocked_permissions;
  // We are not initializing |minimum_version_required| from |default_settings|
  // here since it's not applicable to default settings.
}

IndividualSettings::~IndividualSettings() {
}

bool IndividualSettings::Parse(const base::DictionaryValue* dict,
                               ParsingScope scope) {
  std::string installation_mode_str;
  if (dict->GetStringWithoutPathExpansion(schema_constants::kInstallationMode,
                                          &installation_mode_str)) {
    if (installation_mode_str == schema_constants::kAllowed) {
      installation_mode = ExtensionManagement::INSTALLATION_ALLOWED;
    } else if (installation_mode_str == schema_constants::kBlocked) {
      installation_mode = ExtensionManagement::INSTALLATION_BLOCKED;
    } else if (installation_mode_str == schema_constants::kForceInstalled) {
      installation_mode = ExtensionManagement::INSTALLATION_FORCED;
    } else if (installation_mode_str == schema_constants::kNormalInstalled) {
      installation_mode = ExtensionManagement::INSTALLATION_RECOMMENDED;
    } else {
      // Invalid value for 'installation_mode'.
      LOG(WARNING) << kMalformedPreferenceWarning;
      return false;
    }

    // Only proceed to fetch update url if force or recommended install mode
    // is set.
    if (installation_mode == ExtensionManagement::INSTALLATION_FORCED ||
        installation_mode == ExtensionManagement::INSTALLATION_RECOMMENDED) {
      if (scope != SCOPE_INDIVIDUAL) {
        // Only individual extensions are allowed to be automatically installed.
        LOG(WARNING) << kMalformedPreferenceWarning;
        return false;
      }
      std::string update_url_str;
      if (dict->GetStringWithoutPathExpansion(schema_constants::kUpdateUrl,
                                              &update_url_str) &&
          GURL(update_url_str).is_valid()) {
        update_url = update_url_str;
      } else {
        // No valid update URL for extension.
        LOG(WARNING) << kMalformedPreferenceWarning;
        return false;
      }
    }
  }

  // Parses the blocked permission settings.
  const base::ListValue* list_value = nullptr;
  base::string16 error;

  // Set default blocked permissions, or replace with extension specific blocks.
  APIPermissionSet parsed_blocked_permissions;
  APIPermissionSet explicitly_allowed_permissions;
  if (dict->GetListWithoutPathExpansion(schema_constants::kAllowedPermissions,
                                        &list_value)) {
    if (!APIPermissionSet::ParseFromJSON(
            list_value, APIPermissionSet::kDisallowInternalPermissions,
            &explicitly_allowed_permissions, &error, nullptr)) {
      LOG(WARNING) << error;
    }
  }
  if (dict->GetListWithoutPathExpansion(schema_constants::kBlockedPermissions,
                                        &list_value)) {
    if (!APIPermissionSet::ParseFromJSON(
            list_value, APIPermissionSet::kDisallowInternalPermissions,
            &parsed_blocked_permissions, &error, nullptr)) {
      LOG(WARNING) << error;
    }
  }
  APIPermissionSet::Difference(parsed_blocked_permissions,
                               explicitly_allowed_permissions,
                               &blocked_permissions);

  // Parses list of Match Patterns into a URLPatternSet.
  auto parse_url_pattern_set = [](const base::DictionaryValue* dict,
                                  const char key[], URLPatternSet* out_value) {
    const base::ListValue* host_list_value = nullptr;

    // Get the list of URLPatterns.
    if (dict->GetListWithoutPathExpansion(key,
                                          &host_list_value)) {
      if (host_list_value->GetSize() >
          schema_constants::kMaxItemsURLPatternSet) {
        LOG(WARNING) << "Exceeded maximum number of URL match patterns ("
                     << schema_constants::kMaxItemsURLPatternSet
                     << ") for attribute '" << key << "'";
        return false;
      }

      out_value->ClearPatterns();
      const int extension_scheme_mask =
          URLPattern::GetValidSchemeMaskForExtensions();
      for (size_t i = 0; i < host_list_value->GetSize(); ++i) {
        std::string unparsed_str;
        host_list_value->GetString(i, &unparsed_str);
        URLPattern pattern(extension_scheme_mask);
        if (unparsed_str != URLPattern::kAllUrlsPattern)
          unparsed_str.append("/*");
        URLPattern::ParseResult parse_result = pattern.Parse(
            unparsed_str, URLPattern::ALLOW_WILDCARD_FOR_EFFECTIVE_TLD);
        if (parse_result != URLPattern::PARSE_SUCCESS) {
          LOG(WARNING) << kMalformedPreferenceWarning;
          LOG(WARNING) << "Invalid URL pattern '" + unparsed_str +
                              "' for attribute " + key;
          return false;
        }
        out_value->AddPattern(pattern);
      }
    }
    return true;
  };

  if (!parse_url_pattern_set(dict, schema_constants::kPolicyBlockedHosts,
                             &policy_blocked_hosts))
    return false;

  if (!parse_url_pattern_set(dict, schema_constants::kPolicyAllowedHosts,
                             &policy_allowed_hosts))
    return false;

  // Parses the minimum version settings.
  std::string minimum_version_required_str;
  if (scope == SCOPE_INDIVIDUAL &&
      dict->GetStringWithoutPathExpansion(
          schema_constants::kMinimumVersionRequired,
          &minimum_version_required_str)) {
    std::unique_ptr<base::Version> version(
        new base::Version(minimum_version_required_str));
    // We accept a general version string here. Note that count of components in
    // version string of extensions is limited to 4.
    if (!version->IsValid())
      LOG(WARNING) << kMalformedPreferenceWarning;
    else
      minimum_version_required = std::move(version);
  }

  if (dict->GetStringWithoutPathExpansion(
          schema_constants::kBlockedInstallMessage, &blocked_install_message)) {
    if (blocked_install_message.length() > kBlockedInstallMessageMaxLength) {
      LOG(WARNING) << "Truncated blocked install message to 1000 characters";
      blocked_install_message.erase(kBlockedInstallMessageMaxLength,
                                    std::string::npos);
    }
  }

  return true;
}

void IndividualSettings::Reset() {
  installation_mode = ExtensionManagement::INSTALLATION_ALLOWED;
  update_url.clear();
  blocked_permissions.clear();
  policy_blocked_hosts.ClearPatterns();
  policy_allowed_hosts.ClearPatterns();
  blocked_install_message.clear();
}

GlobalSettings::GlobalSettings() {
  Reset();
}

GlobalSettings::~GlobalSettings() {
}

void GlobalSettings::Reset() {
  has_restricted_install_sources = false;
  install_sources.ClearPatterns();
  has_restricted_allowed_types = false;
  allowed_types.clear();
}

}  // namespace internal

}  // namespace extensions