/******************************************************************************

 * Project:  OGR

 * Purpose:  OGRGMLASDriver implementation

 * Author:   Even Rouault, <even dot rouault at spatialys dot com>

 *

 * Initial development funded by the European Earth observation programme

 * Copernicus

 *

 ******************************************************************************

 * Copyright (c) 2016, Even Rouault, <even dot rouault at spatialys dot com>

 *

 * SPDX-License-Identifier: MIT

 ****************************************************************************/

#include "ogr_gmlas.h"

#include "cpl_minixml.h"

#include <algorithm>

#ifdef EMBED_RESOURCE_FILES

#include "embedded_resources.h"

#endif

/************************************************************************/

/*                              Finalize()                              */

/************************************************************************/

void GMLASConfiguration::Finalize()

{

    if (m_bAllowXSDCache && m_osXSDCacheDirectory.empty())

    {

        m_osXSDCacheDirectory = GDALGetCacheDirectory();

        if (m_osXSDCacheDirectory.empty())

        {

            CPLError(CE_Warning, CPLE_AppDefined,

                     "Could not determine a directory for GMLAS XSD cache");

        }

        else

        {

            m_osXSDCacheDirectory = CPLFormFilenameSafe(

                m_osXSDCacheDirectory, "gmlas_xsd_cache", nullptr);

            CPLDebug("GMLAS", "XSD cache directory: %s",

                     m_osXSDCacheDirectory.c_str());

        }

    }

}

/************************************************************************/

/*                          CPLGetXMLBoolValue()                        */

/************************************************************************/

static bool CPLGetXMLBoolValue(CPLXMLNode *psNode, const char *pszKey,

                               bool bDefault)

{

    const char *pszVal = CPLGetXMLValue(psNode, pszKey, nullptr);

    if (pszVal)

        return CPLTestBool(pszVal);

    else

        return bDefault;

}

/************************************************************************/

/*                            IsValidXPath()                            */

/************************************************************************/

static bool IsValidXPath(const CPLString &osXPath)

{

    // Check that the XPath syntax belongs to the subset we

    // understand

    bool bOK = !osXPath.empty();

    for (size_t i = 0; i < osXPath.size(); ++i)

    {

        const char chCur = osXPath[i];

        if (chCur == '/')

        {

            // OK

        }

        else if (chCur == '@' && (i == 0 || osXPath[i - 1] == '/') &&

                 i < osXPath.size() - 1 &&

                 isalpha(static_cast<unsigned char>(osXPath[i + 1])))

        {

            // OK

        }

        else if (chCur == '_' || isalpha(static_cast<unsigned char>(chCur)))

        {

            // OK

        }

        else if (isdigit(static_cast<unsigned char>(chCur)) && i > 0 &&

                 (isalnum(static_cast<unsigned char>(osXPath[i - 1])) ||

                  osXPath[i - 1] == '_'))

        {

            // OK

        }

        else if (chCur == ':' && i > 0 &&

                 (isalnum(static_cast<unsigned char>(osXPath[i - 1])) ||

                  osXPath[i - 1] == '_') &&

                 i < osXPath.size() - 1 &&

                 isalpha(static_cast<unsigned char>(osXPath[i + 1])))

        {

            // OK

        }

        else

        {

            bOK = false;

            break;

        }

    }

    return bOK;

}

/************************************************************************/

/*                    GMLASConfigurationErrorHandler()                  */

/************************************************************************/

static void CPL_STDCALL GMLASConfigurationErrorHandler(CPLErr /*eErr*/,

                                                       CPLErrorNum /*nType*/,

                                                       const char *pszMsg)

{

    std::vector<CPLString> *paosErrors =

        static_cast<std::vector<CPLString> *>(CPLGetErrorHandlerUserData());

    paosErrors->push_back(pszMsg);

}

/************************************************************************/

/*                           ParseNamespaces()                          */

/************************************************************************/

static void ParseNamespaces(CPLXMLNode *psContainerNode,

                            std::map<CPLString, CPLString> &oMap)

{

    CPLXMLNode *psNamespaces = CPLGetXMLNode(psContainerNode, "Namespaces");

    if (psNamespaces != nullptr)

    {

        for (CPLXMLNode *psIter = psNamespaces->psChild; psIter != nullptr;

             psIter = psIter->psNext)

        {

            if (psIter->eType == CXT_Element &&

                EQUAL(psIter->pszValue, "Namespace"))

            {

                const std::string osPrefix =

                    CPLGetXMLValue(psIter, "prefix", "");

                const std::string osURI = CPLGetXMLValue(psIter, "uri", "");

                if (!osPrefix.empty() && !osURI.empty())

                {

                    if (oMap.find(osPrefix) == oMap.end())

                    {

                        oMap[osPrefix] = osURI;

                    }

                    else

                    {

                        CPLError(CE_Warning, CPLE_AppDefined,

                                 "Prefix %s was already mapped to %s. "

                                 "Attempt to map it to %s ignored",

                                 osPrefix.c_str(), oMap[osPrefix].c_str(),

                                 osURI.c_str());

                    }

                }

            }

        }

    }

}

/************************************************************************/

/*                           GetDefaultConfFile()                       */

/************************************************************************/

/* static */

std::string GMLASConfiguration::GetDefaultConfFile(bool &bUnlinkAfterUse)

{

    bUnlinkAfterUse = false;

#if !defined(USE_ONLY_EMBEDDED_RESOURCE_FILES)

    const char *pszConfigFile = CPLFindFile("gdal", szDEFAULT_CONF_FILENAME);

    if (pszConfigFile)

        return pszConfigFile;

#endif

#ifdef EMBED_RESOURCE_FILES

    static const bool bOnce [[maybe_unused]] = []()

    {

        CPLDebug("GMLAS", "Using embedded %s", szDEFAULT_CONF_FILENAME);

        return true;

    }();

    bUnlinkAfterUse = true;

    const std::string osTmpFilename =

        VSIMemGenerateHiddenFilename(szDEFAULT_CONF_FILENAME);

    VSIFCloseL(VSIFileFromMemBuffer(

        osTmpFilename.c_str(),

        const_cast<GByte *>(

            reinterpret_cast<const GByte *>(GMLASConfXMLGetFileContent())),

        static_cast<int>(strlen(GMLASConfXMLGetFileContent())),

        /* bTakeOwnership = */ false));

    return osTmpFilename;

#else

    return std::string();

#endif

}

/************************************************************************/

/*                                 Load()                               */

/************************************************************************/

bool GMLASConfiguration::Load(const char *pszFilename)

{

    // Allow configuration to be inlined

    CPLXMLNode *psRoot = STARTS_WITH(pszFilename, "<Configuration")

                             ? CPLParseXMLString(pszFilename)

                             : CPLParseXMLFile(pszFilename);

    if (psRoot == nullptr)

    {

        Finalize();

        return false;

    }

    CPLXMLTreeCloser oCloser(psRoot);

    CPL_IGNORE_RET_VAL(oCloser);

    // Validate the configuration file

    if (CPLTestBool(CPLGetConfigOption("GDAL_XML_VALIDATION", "YES")))

    {

#ifdef EMBED_RESOURCE_FILES

        std::string osTmpFilename;

        CPLErrorStateBackuper oErrorStateBackuper(CPLQuietErrorHandler);

#endif

#ifdef USE_ONLY_EMBEDDED_RESOURCE_FILES

        const char *pszXSD = nullptr;

#else

        const char *pszXSD = CPLFindFile("gdal", "gmlasconf.xsd");

#endif

#ifdef EMBED_RESOURCE_FILES

        if (!pszXSD)

        {

            static const bool bOnce [[maybe_unused]] = []()

            {

                CPLDebug("GMLAS", "Using embedded gmlasconf.xsd");

                return true;

            }();

            osTmpFilename = VSIMemGenerateHiddenFilename("gmlasconf.xsd");

            pszXSD = osTmpFilename.c_str();

            VSIFCloseL(VSIFileFromMemBuffer(

                osTmpFilename.c_str(),

                const_cast<GByte *>(reinterpret_cast<const GByte *>(

                    GMLASConfXSDGetFileContent())),

                static_cast<int>(strlen(GMLASConfXSDGetFileContent())),

                /* bTakeOwnership = */ false));

        }

#else

        if (pszXSD)

#endif

        {

            std::vector<CPLString> aosErrors;

            const CPLErr eErrClass = CPLGetLastErrorType();

            const CPLErrorNum nErrNum = CPLGetLastErrorNo();

            const CPLString osErrMsg = CPLGetLastErrorMsg();

            CPLPushErrorHandlerEx(GMLASConfigurationErrorHandler, &aosErrors);

            int bRet = CPLValidateXML(pszFilename, pszXSD, nullptr);

            CPLPopErrorHandler();

            if (!bRet && !aosErrors.empty() &&

                strstr(aosErrors[0].c_str(), "missing libxml2 support") ==

                    nullptr)

            {

                for (size_t i = 0; i < aosErrors.size(); i++)

                {

                    CPLError(CE_Warning, CPLE_AppDefined, "%s",

                             aosErrors[i].c_str());

                }

            }

            else

            {

                CPLErrorSetState(eErrClass, nErrNum, osErrMsg);

            }

        }

#ifdef EMBED_RESOURCE_FILES

        if (!osTmpFilename.empty())

            VSIUnlink(osTmpFilename.c_str());

#endif

    }

    m_bAllowRemoteSchemaDownload =

        CPLGetXMLBoolValue(psRoot, "=Configuration.AllowRemoteSchemaDownload",

                           ALLOW_REMOTE_SCHEMA_DOWNLOAD_DEFAULT);

    m_bAllowXSDCache = CPLGetXMLBoolValue(

        psRoot, "=Configuration.SchemaCache.enabled", ALLOW_XSD_CACHE_DEFAULT);

    if (m_bAllowXSDCache)

    {

        m_osXSDCacheDirectory =

            CPLGetXMLValue(psRoot, "=Configuration.SchemaCache.Directory", "");

    }

    m_bSchemaFullChecking = CPLGetXMLBoolValue(

        psRoot, "=Configuration.SchemaAnalysisOptions.SchemaFullChecking",

        SCHEMA_FULL_CHECKING_DEFAULT);

    m_bHandleMultipleImports = CPLGetXMLBoolValue(

        psRoot, "=Configuration.SchemaAnalysisOptions.HandleMultipleImports",

        HANDLE_MULTIPLE_IMPORTS_DEFAULT);

    m_bValidate = CPLGetXMLBoolValue(

        psRoot, "=Configuration.Validation.enabled", VALIDATE_DEFAULT);

    if (m_bValidate)

    {

        m_bFailIfValidationError =

            CPLGetXMLBoolValue(psRoot, "=Configuration.Validation.FailIfError",

                               FAIL_IF_VALIDATION_ERROR_DEFAULT);

    }

    m_bExposeMetadataLayers =

        CPLGetXMLBoolValue(psRoot, "=Configuration.ExposeMetadataLayers",

                           EXPOSE_METADATA_LAYERS_DEFAULT);

    m_bAlwaysGenerateOGRId = CPLGetXMLBoolValue(

        psRoot, "=Configuration.LayerBuildingRules.AlwaysGenerateOGRId",

        ALWAYS_GENERATE_OGR_ID_DEFAULT);

    m_bRemoveUnusedLayers = CPLGetXMLBoolValue(

        psRoot, "=Configuration.LayerBuildingRules.RemoveUnusedLayers",

        REMOVE_UNUSED_LAYERS_DEFAULT);

    m_bRemoveUnusedFields = CPLGetXMLBoolValue(

        psRoot, "=Configuration.LayerBuildingRules.RemoveUnusedFields",

        REMOVE_UNUSED_FIELDS_DEFAULT);

    m_bUseArrays = CPLGetXMLBoolValue(

        psRoot, "=Configuration.LayerBuildingRules.UseArrays",

        USE_ARRAYS_DEFAULT);

    m_bUseNullState = CPLGetXMLBoolValue(

        psRoot, "=Configuration.LayerBuildingRules.UseNullState",

        USE_NULL_STATE_DEFAULT);

    m_bIncludeGeometryXML = CPLGetXMLBoolValue(

        psRoot, "=Configuration.LayerBuildingRules.GML.IncludeGeometryXML",

        INCLUDE_GEOMETRY_XML_DEFAULT);

    m_bInstantiateGMLFeaturesOnly = CPLGetXMLBoolValue(

        psRoot,

        "=Configuration.LayerBuildingRules.GML.InstantiateGMLFeaturesOnly",

        INSTANTIATE_GML_FEATURES_ONLY_DEFAULT);

    m_nIdentifierMaxLength = atoi(CPLGetXMLValue(

        psRoot, "=Configuration.LayerBuildingRules.IdentifierMaxLength", "0"));

    m_bCaseInsensitiveIdentifier = CPLGetXMLBoolValue(

        psRoot, "=Configuration.LayerBuildingRules.CaseInsensitiveIdentifier",

        CASE_INSENSITIVE_IDENTIFIER_DEFAULT);

    m_bPGIdentifierLaundering = CPLGetXMLBoolValue(

        psRoot,

        "=Configuration.LayerBuildingRules.PostgreSQLIdentifierLaundering",

        PG_IDENTIFIER_LAUNDERING_DEFAULT);

    CPLXMLNode *psFlatteningRules = CPLGetXMLNode(

        psRoot, "=Configuration.LayerBuildingRules.FlatteningRules");

    if (psFlatteningRules)

    {

        m_nMaximumFieldsForFlattening = atoi(CPLGetXMLValue(

            psFlatteningRules, "MaximumNumberOfFields",

            CPLSPrintf("%d", MAXIMUM_FIELDS_FLATTENING_DEFAULT)));

        ParseNamespaces(psFlatteningRules, m_oMapPrefixToURIFlatteningRules);

        for (CPLXMLNode *psIter = psFlatteningRules->psChild; psIter != nullptr;

             psIter = psIter->psNext)

        {

            if (psIter->eType == CXT_Element &&

                EQUAL(psIter->pszValue, "ForceFlatteningXPath"))

            {

                m_osForcedFlattenedXPath.push_back(

                    CPLGetXMLValue(psIter, "", ""));

            }

            else if (psIter->eType == CXT_Element &&

                     EQUAL(psIter->pszValue, "DisableFlatteningXPath"))

            {

                m_osDisabledFlattenedXPath.push_back(

                    CPLGetXMLValue(psIter, "", ""));

            }

        }

    }

    const char *pszSWEProcessingActivation = CPLGetXMLValue(

        psRoot, "=Configuration.LayerBuildingRules.SWEProcessing.Activation",

        "ifSWENamespaceFoundInTopElement");

    if (EQUAL(pszSWEProcessingActivation, "ifSWENamespaceFoundInTopElement"))

        m_eSWEActivationMode = SWE_ACTIVATE_IF_NAMESPACE_FOUND;

    else if (CPLTestBool(pszSWEProcessingActivation))

        m_eSWEActivationMode = SWE_ACTIVATE_TRUE;

    else

        m_eSWEActivationMode = SWE_ACTIVATE_FALSE;

    m_bSWEProcessDataRecord = CPLTestBool(CPLGetXMLValue(

        psRoot,

        "=Configuration.LayerBuildingRules.SWEProcessing.ProcessDataRecord",

        "true"));

    m_bSWEProcessDataArray = CPLTestBool(CPLGetXMLValue(

        psRoot,

        "=Configuration.LayerBuildingRules.SWEProcessing.ProcessDataArray",

        "true"));

    CPLXMLNode *psTypingConstraints =

        CPLGetXMLNode(psRoot, "=Configuration.TypingConstraints");

    if (psTypingConstraints)

    {

        ParseNamespaces(psTypingConstraints, m_oMapPrefixToURITypeConstraints);

        for (CPLXMLNode *psIter = psTypingConstraints->psChild;

             psIter != nullptr; psIter = psIter->psNext)

        {

            if (psIter->eType == CXT_Element &&

                EQUAL(psIter->pszValue, "ChildConstraint"))

            {

                const CPLString &osXPath(

                    CPLGetXMLValue(psIter, "ContainerXPath", ""));

                CPLXMLNode *psChildrenTypes =

                    CPLGetXMLNode(psIter, "ChildrenElements");

                if (IsValidXPath(osXPath))

                {

                    for (CPLXMLNode *psIter2 = psChildrenTypes

                                                   ? psChildrenTypes->psChild

                                                   : nullptr;

                         psIter2 != nullptr; psIter2 = psIter2->psNext)

                    {

                        if (psIter2->eType == CXT_Element &&

                            EQUAL(psIter2->pszValue, "Element"))

                        {

                            m_oMapChildrenElementsConstraints[osXPath]

                                .push_back(CPLGetXMLValue(psIter2, "", ""));

                        }

                    }

                }

                else

                {

                    CPLError(CE_Warning, CPLE_AppDefined,

                             "XPath syntax %s not supported", osXPath.c_str());

                }

            }

        }

    }

    CPLXMLNode *psIgnoredXPaths =

        CPLGetXMLNode(psRoot, "=Configuration.IgnoredXPaths");

    if (psIgnoredXPaths)

    {

        const bool bGlobalWarnIfIgnoredXPathFound = CPLGetXMLBoolValue(

            psIgnoredXPaths, "WarnIfIgnoredXPathFoundInDocInstance",

            WARN_IF_EXCLUDED_XPATH_FOUND_DEFAULT);

        ParseNamespaces(psIgnoredXPaths, m_oMapPrefixToURIIgnoredXPaths);

        for (CPLXMLNode *psIter = psIgnoredXPaths->psChild; psIter != nullptr;

             psIter = psIter->psNext)

        {

            if (psIter->eType == CXT_Element &&

                EQUAL(psIter->pszValue, "XPath"))

            {

                const CPLString &osXPath(CPLGetXMLValue(psIter, "", ""));

                if (IsValidXPath(osXPath))

                {

                    m_aosIgnoredXPaths.push_back(osXPath);

                    const bool bWarnIfIgnoredXPathFound = CPLGetXMLBoolValue(

                        psIter, "warnIfIgnoredXPathFoundInDocInstance",

                        bGlobalWarnIfIgnoredXPathFound);

                    m_oMapIgnoredXPathToWarn[osXPath] =

                        bWarnIfIgnoredXPathFound;

                }

                else

                {

                    CPLError(CE_Warning, CPLE_AppDefined,

                             "XPath syntax %s not supported", osXPath.c_str());

                }

            }

        }

    }

    CPLXMLNode *psXLinkResolutionNode =

        CPLGetXMLNode(psRoot, "=Configuration.XLinkResolution");

    if (psXLinkResolutionNode != nullptr)

        m_oXLinkResolution.LoadFromXML(psXLinkResolutionNode);

    // Parse WriterConfig

    CPLXMLNode *psWriterConfig =

        CPLGetXMLNode(psRoot, "=Configuration.WriterConfig");

    if (psWriterConfig != nullptr)

    {

        m_nIndentSize =

            atoi(CPLGetXMLValue(psWriterConfig, "IndentationSize",

                                CPLSPrintf("%d", INDENT_SIZE_DEFAULT)));

        m_nIndentSize =

            std::min(INDENT_SIZE_MAX, std::max(INDENT_SIZE_MIN, m_nIndentSize));

        m_osComment = CPLGetXMLValue(psWriterConfig, "Comment", "");

        m_osLineFormat = CPLGetXMLValue(psWriterConfig, "LineFormat", "");

        m_osSRSNameFormat = CPLGetXMLValue(psWriterConfig, "SRSNameFormat", "");

        m_osWrapping = CPLGetXMLValue(psWriterConfig, "Wrapping",

                                      szWFS2_FEATURECOLLECTION);

        m_osTimestamp = CPLGetXMLValue(psWriterConfig, "Timestamp", "");

        m_osWFS20SchemaLocation = CPLGetXMLValue(

            psWriterConfig, "WFS20SchemaLocation", szWFS20_SCHEMALOCATION);

    }

    Finalize();

    return true;

}

/************************************************************************/

/*                               LoadFromXML()                          */

/************************************************************************/

bool GMLASXLinkResolutionConf::LoadFromXML(CPLXMLNode *psRoot)

{

    m_nTimeOut = atoi(CPLGetXMLValue(psRoot, "Timeout", "0"));

    m_nMaxFileSize = atoi(CPLGetXMLValue(

        psRoot, "MaxFileSize", CPLSPrintf("%d", MAX_FILE_SIZE_DEFAULT)));

    m_nMaxGlobalResolutionTime =

        atoi(CPLGetXMLValue(psRoot, "MaxGlobalResolutionTime", "0"));

    m_osProxyServerPort = CPLGetXMLValue(psRoot, "ProxyServerPort", "");

    m_osProxyUserPassword = CPLGetXMLValue(psRoot, "ProxyUserPassword", "");

    m_osProxyAuth = CPLGetXMLValue(psRoot, "ProxyAuth", "");

    m_osCacheDirectory = CPLGetXMLValue(psRoot, "CacheDirectory", "");

    if (m_osCacheDirectory.empty())

    {

        m_osCacheDirectory = GDALGetCacheDirectory();

        if (!m_osCacheDirectory.empty())

        {

            m_osCacheDirectory = CPLFormFilenameSafe(

                m_osCacheDirectory, "xlink_resolved_cache", nullptr);

        }

    }

    m_bDefaultResolutionEnabled =

        CPLGetXMLBoolValue(psRoot, "DefaultResolution.enabled",

                           DEFAULT_RESOLUTION_ENABLED_DEFAULT);

    m_bDefaultAllowRemoteDownload =

        CPLGetXMLBoolValue(psRoot, "DefaultResolution.AllowRemoteDownload",

                           ALLOW_REMOTE_DOWNLOAD_DEFAULT);

    // TODO when we support other modes

    // m_eDefaultResolutionMode =

    m_nDefaultResolutionDepth =

        atoi(CPLGetXMLValue(psRoot, "DefaultResolution.ResolutionDepth", "1"));

    m_bDefaultCacheResults = CPLGetXMLBoolValue(

        psRoot, "DefaultResolution.CacheResults", CACHE_RESULTS_DEFAULT);

    CPLXMLNode *psIterURL = psRoot->psChild;

    for (; psIterURL != nullptr; psIterURL = psIterURL->psNext)

    {

        if (psIterURL->eType == CXT_Element &&

            strcmp(psIterURL->pszValue, "URLSpecificResolution") == 0)

        {

            GMLASXLinkResolutionConf::URLSpecificResolution oItem;

            oItem.m_osURLPrefix = CPLGetXMLValue(psIterURL, "URLPrefix", "");

            oItem.m_bAllowRemoteDownload =

                CPLGetXMLBoolValue(psIterURL, "AllowRemoteDownload",

                                   ALLOW_REMOTE_DOWNLOAD_DEFAULT);

            const char *pszResolutionModel =

                CPLGetXMLValue(psIterURL, "ResolutionMode", "RawContent");

            if (EQUAL(pszResolutionModel, "RawContent"))

                oItem.m_eResolutionMode = RawContent;

            else

                oItem.m_eResolutionMode = FieldsFromXPath;

            oItem.m_nResolutionDepth =

                atoi(CPLGetXMLValue(psIterURL, "ResolutionDepth", "1"));

            oItem.m_bCacheResults = CPLGetXMLBoolValue(

                psIterURL, "CacheResults", CACHE_RESULTS_DEFAULT);

            CPLXMLNode *psIter = psIterURL->psChild;

            for (; psIter != nullptr; psIter = psIter->psNext)

            {

                if (psIter->eType == CXT_Element &&

                    strcmp(psIter->pszValue, "HTTPHeader") == 0)

                {

                    CPLString osName(CPLGetXMLValue(psIter, "Name", ""));

                    CPLString osValue(CPLGetXMLValue(psIter, "Value", ""));

                    oItem.m_aosNameValueHTTPHeaders.push_back(

                        std::pair<CPLString, CPLString>(osName, osValue));

                }

                else if (psIter->eType == CXT_Element &&

                         strcmp(psIter->pszValue, "Field") == 0)

                {

                    URLSpecificResolution::XPathDerivedField oField;

                    oField.m_osName = CPLGetXMLValue(psIter, "Name", "");

                    oField.m_osType = CPLGetXMLValue(psIter, "Type", "");

                    oField.m_osXPath = CPLGetXMLValue(psIter, "XPath", "");

                    oItem.m_aoFields.push_back(std::move(oField));

                }

            }

            m_aoURLSpecificRules.push_back(std::move(oItem));

        }

    }

    m_bResolveInternalXLinks = CPLGetXMLBoolValue(

        psRoot, "ResolveInternalXLinks", INTERNAL_XLINK_RESOLUTION_DEFAULT);

    return true;

}