#include "dbc_decode_builder.h"
#include "dbc_decoder.h"
#include "dbc_parser.h"
#include "dbc_statement_handler.h"
#include "dbc_tree_builder.h"
#include <clocale>
#include <limits>
#include <locale>

#include <QtTest>
#include <chrono>
#include <filesystem>
#include <fstream>

#define CHECK(condition, name) QVERIFY2((condition), std::string(name).c_str())
#include <stdexcept>

struct Fixture {
    std::filesystem::path path = std::filesystem::temp_directory_path() /
                                 ("dbc_parser_test_" + std::to_string(std::chrono::steady_clock::now().time_since_epoch().count()) + ".dbc");
    ~Fixture() {
        std::error_code error;
        std::filesystem::remove(path, error);
    }
    void Write(const std::string &text) const {
        std::ofstream output(path);
        output << text;
        if (!output)
            throw std::runtime_error("Cannot write test fixture.");
    }
};

class CommaDecimalPunctuation : public std::numpunct<char> {
protected:
    char do_decimal_point() const override { return ','; }
    char do_thousands_sep() const override { return '.'; }
    std::string do_grouping() const override { return "\3"; }
};

class ApplicationLocaleGuard {
public:
    ApplicationLocaleGuard()
        : previousCppLocale(std::locale()), previousCLocale(std::setlocale(LC_ALL, nullptr)) {}
    ~ApplicationLocaleGuard() {
        std::locale::global(previousCppLocale);
        std::setlocale(LC_ALL, previousCLocale.c_str());
    }

private:
    std::locale previousCppLocale;
    std::string previousCLocale;
};

class CountingHandler : public DbcStatementHandler {
public:
    inline static int instances = 0;
    inline static int calls = 0;
    CountingHandler() { ++instances; }
    void Handle(const std::string &, DbcParseContext &context) const override {
        ++calls;
        context.database.frames.emplace_back();
    }
};

std::string SignalLine(const std::string &start, const std::string &length,
                       const std::string &order, const std::string &factor,
                       const std::string &offset, const std::string &minimum,
                       const std::string &maximum, const std::string &name = "Value") {
    return "SG_ " + name + " : " + start + "|" + length + "@" + order +
           " (" + factor + "," + offset + ") [" + minimum + "|" + maximum + "] \"\" ECU";
}

class DbcParserTest : public QObject {
    Q_OBJECT
private:
    void CheckPhysicalNumbers();
    void RejectSignal(const Fixture &fixture, const std::string &line, unsigned payload = 8U) {
        fixture.Write("BO_ 1 Frame: " + std::to_string(payload) + " ECU\n\n" + line + "\n");
        try {
            DbcParser().ParseFile(fixture.path.string());
            CHECK(false, "Reject " + line);
        } catch (const std::runtime_error &error) {
            const std::string prefix = fixture.path.string() + ":3: ";
            CHECK(std::string(error.what()).find(prefix) == 0U &&
                          std::string(error.what()).size() > prefix.size(),
                  "Reject " + line);
        }
    }
private Q_SLOTS:
    void diagnostics();
    void diagnosticErrors();
    void diagnosticUnsupportedStatements();
    void diagnosticNamespaceBoundaries();
    void diagnosticFormatting();
    void multiplexing();
    void multiplexingBoundaries();
    void validFrames();
    void invalidFrames();
    void duplicateFrames();
    void duplicateSignals();
    void distinctDefinitions();
    void comments();
    void invalidComments_data();
    void invalidComments();
    void integration();
    void invalidSignals();
    void validSignals();
    void physicalNumbersCppLocale();
    void physicalNumbersCLocale();
    void dispatch();
    void independentSessions();
    void valueDescriptions();
    void invalidValueDescriptions();
};

void DbcParserTest::diagnostics() {
    Fixture fixture;
    fixture.Write("VERSION \"test\"\n"
                  "NS_ :\n"
                  "    CM_\n"
                  "    BA_\n"
                  "    SIG_VALTYPE_\n"
                  "    SG_MUL_VAL_\n\n"
                  "BS_:\n"
                  "BU_: ECU\n"
                  "BO_ 1 Frame: 1 ECU\n"
                  "SG_ Value : 0|8@1+ (1,0) [0|255] \"\" ECU\n"
                  "SIG_VALTYPE_ 1 Value : 1;\n"
                  "BA_ \"SignalType\" SG_ 1 Value 1;\n"
                  "VENDOR_EXTENSION_ data;\n");
    const DbcParseResult result = DbcParser().ParseFileWithDiagnostics(fixture.path.string());
    CHECK(!result.HasErrors() && result.database.frames.size() == 1U,
          "Warnings preserve the supported database");
    QCOMPARE(result.diagnostics.size(), std::size_t(3U));
    for (std::size_t index = 0U; index < result.diagnostics.size(); ++index) {
        const DbcDiagnostic &diagnostic = result.diagnostics[index];
        CHECK(diagnostic.severity == DbcDiagnosticSeverity::Warning &&
                      diagnostic.code == DbcDiagnosticCode::UnsupportedStatement,
              "Unsupported statements have structured warning severity and code");
        QCOMPARE(diagnostic.filePath, fixture.path.string());
        QCOMPARE(diagnostic.lineNumber, 12U + index);
        CHECK(diagnostic.message.find("ignored") != std::string::npos,
              "Warning explains unsupported syntax");
    }
    CHECK(DbcParser().ParseFile(fixture.path.string()).frames.size() == 1U,
          "Legacy API accepts files with warnings");
    fixture.Write("VERSION \"\"\nNS_:\nSIG_VALTYPE_\n\tBA_\n BS_ :\n BU_ : ECU\n");
    const DbcParseResult headers = DbcParser().ParseFileWithDiagnostics(fixture.path.string());
    CHECK(headers.diagnostics.empty(), "Common header variants stay quiet");
    fixture.Write("NS_ :\n    BA_\n  BO_\n");
    CHECK(DbcParser().ParseFileWithDiagnostics(fixture.path.string()).HasErrors(),
          "Namespace handling does not swallow a malformed frame");
}

void DbcParserTest::diagnosticErrors() {
    Fixture fixture;
    struct ErrorCase {
        const char *text;
        DbcDiagnosticCode code;
        std::size_t line;
    };
    const ErrorCase cases[] = {
        {"UNKNOWN_ data;\n\nBO_ invalid Frame: 1 ECU\n",
         DbcDiagnosticCode::InvalidStatement, 3U},
        {"BO_ 1 Frame: 1 ECU\nSG_MUL_VAL_ 1 Value Mode 1-2;\n",
         DbcDiagnosticCode::UnsupportedStatement, 2U},
        {"BO_ 1 Frame: 1 ECU\nVAL_ 1 Missing 0 \"Off\";\n",
         DbcDiagnosticCode::InvalidValueDescription, 2U},
        {"BO_ 1 Frame: 1 ECU\nSG_ Value m1 : 0|8@1+ (1,0) [0|255] \"\" ECU\n",
         DbcDiagnosticCode::InvalidMultiplexing, 2U},
        {"BO_ 1 Frame: 1 ECU\nSG_ Mode M : 0|8@1- (1,0) [-128|127] \"\" ECU\n",
         DbcDiagnosticCode::InvalidMultiplexing, 2U},
        {"VAL_ broken\n", DbcDiagnosticCode::InvalidValueDescription, 1U},
        {"SG_ Value : 0|8@1+ (1,0) [0|255] \"\" ECU\n",
         DbcDiagnosticCode::InvalidStatement, 1U},
        {"BO_ 1 Frame: 1 ECU\nBO_ 1 Duplicate: 1 ECU\n",
         DbcDiagnosticCode::InvalidStatement, 2U},
        {"BO_ 1 Frame: 1 ECU\nSG_ Value : 0|8@1+ (1,0) [0|255] \"\" ECU\n"
         "SG_ Value : 0|8@1+ (1,0) [0|255] \"\" ECU\n",
         DbcDiagnosticCode::InvalidStatement, 3U},
        {"BO_ 1 Frame: 1 ECU\nSG_ Value : 8|8@1+ (1,0) [0|255] \"\" ECU\n",
         DbcDiagnosticCode::InvalidStatement, 2U},
        {"BO_ 1 Frame: 1 ECU\nVAL_ 2 Missing 0 \"Off\";\n",
         DbcDiagnosticCode::InvalidValueDescription, 2U},
        {"BO_ 1 Frame: 1 ECU\nSG_ Value : 0|8@1+ (1,0) [0|255] \"\" ECU\n"
         "VAL_ 1 Value 0 \"Off\";\nVAL_ 1 Value 0 \"Duplicate\";\n",
         DbcDiagnosticCode::InvalidValueDescription, 4U},
        {"BO_ 1 Frame: 2 ECU\nSG_ Mode M : 0|1@1+ (1,0) [0|1] \"\" ECU\n"
         "SG_ Value m2 : 8|8@1+ (1,0) [0|255] \"\" ECU\n",
         DbcDiagnosticCode::InvalidMultiplexing, 3U},
        {"BO_ 1 Frame: 2 ECU\nSG_ Mode M : 0|8@1+ (1,0) [0|255] \"\" ECU\n"
         "SG_ Other M : 8|8@1+ (1,0) [0|255] \"\" ECU\n",
         DbcDiagnosticCode::InvalidMultiplexing, 3U},
        {"BO_ 1 Frame: 1 ECU\nSG_ First : 0|8@1+ (1,0) [0|255] \"\" ECU\n"
         "SG_ Second : 7|8@0+ (1,0) [0|255] \"\" ECU\n",
         DbcDiagnosticCode::InvalidMultiplexing, 3U}
    };
    for (const ErrorCase &test : cases) {
        fixture.Write(test.text);
        const DbcParseResult result = DbcParser().ParseFileWithDiagnostics(fixture.path.string());
        CHECK(result.HasErrors() && result.database.frames.empty(),
              "Failed parse never returns a partial database");
        const DbcDiagnostic &diagnostic = result.diagnostics.back();
        CHECK(diagnostic.severity == DbcDiagnosticSeverity::Error && diagnostic.code == test.code,
              "Error has expected severity and code");
        QCOMPARE(diagnostic.filePath, fixture.path.string());
        QCOMPARE(diagnostic.lineNumber, test.line);
        CHECK(!diagnostic.message.empty(), "Error includes a message");
        const bool hasWarning = std::string(test.text).find("UNKNOWN_") == 0U;
        QCOMPARE(result.diagnostics.size(), hasWarning ? std::size_t(2U) : std::size_t(1U));
        try {
            DbcParser().ParseFile(fixture.path.string());
            CHECK(false, "Legacy parser must throw");
        } catch (const std::runtime_error &error) {
            QCOMPARE(std::string(error.what()), fixture.path.string() + ":" +
                     std::to_string(test.line) + ": " + diagnostic.message);
        }
    }
    const std::string missingPath = fixture.path.string() + ".missing";
    const DbcParseResult missing = DbcParser().ParseFileWithDiagnostics(missingPath);
    CHECK(missing.HasErrors() && missing.database.frames.empty(), "Missing file returns error");
    QCOMPARE(missing.diagnostics.size(), std::size_t(1U));
    CHECK(missing.diagnostics[0].code == DbcDiagnosticCode::FileOpenError,
          "Missing file has a distinct code");
    QCOMPARE(missing.diagnostics[0].lineNumber, std::size_t(0U));
    QCOMPARE(missing.diagnostics[0].filePath, missingPath);
    QCOMPARE(missing.diagnostics[0].message, "Failed to open DBC file: " + missingPath);
    try {
        DbcParser().ParseFile(missingPath);
        CHECK(false, "Legacy API throws on missing file");
    } catch (const std::runtime_error &error) {
        QCOMPARE(std::string(error.what()), missing.diagnostics[0].message);
    }
    const std::string directoryPath = fixture.path.parent_path().string();
    const DbcParseResult directory = DbcParser().ParseFileWithDiagnostics(directoryPath);
    CHECK(directory.HasErrors() && directory.database.frames.empty(),
          "Directory cannot be parsed as a file");
    QCOMPARE(directory.diagnostics.size(), std::size_t(1U));
    CHECK(directory.diagnostics[0].code == DbcDiagnosticCode::FileReadError ||
                  directory.diagnostics[0].code == DbcDiagnosticCode::FileOpenError,
          "Directory produces a file-level error on supported platforms");
    QCOMPARE(directory.diagnostics[0].lineNumber, std::size_t(0U));
    QCOMPARE(directory.diagnostics[0].filePath, directoryPath);
#ifdef __linux__
    CHECK(directory.diagnostics[0].code == DbcDiagnosticCode::FileReadError,
          "Linux directory input exercises the read-error path");
    QCOMPARE(directory.diagnostics[0].message, "Failed to read DBC file: " + directoryPath);
#endif
    try {
        DbcParser().ParseFile(directoryPath);
        CHECK(false, "Legacy API throws on unreadable input");
    } catch (const std::runtime_error &error) {
        QCOMPARE(std::string(error.what()), directory.diagnostics[0].message);
    }
    fixture.Write("BO_ 1 Frame: 1 ECU\n");
    CHECK(DbcParser().ParseFileWithDiagnostics(fixture.path.string()).diagnostics.empty(),
          "Diagnostics belong to an independent parse session");
}

void DbcParserTest::diagnosticUnsupportedStatements() {
    Fixture fixture;
    const std::string definitions =
        "BO_ 1 Frame: 1 ECU\nSG_ Value : 0|8@1+ (2,10) [10|520] \"V\" ECU\n"
        "CM_ SG_ 1 Value \"Signal comment\";\nVAL_ 1 Value 1 \"On\";\n";
    const std::vector<std::string> statements = {
        "SIG_VALTYPE_ 1 Value : 1;", "SIG_VALTYPE_ 1 Value : 2;",
        "BA_ \"SignalType\" SG_ 1 Value 1;",
        "BA_DEF_ SG_ \"SignalType\" INT 0 1;",
        "BA_DEF_DEF_ \"SignalType\" 0;",
        "BA_DEF_REL_ BU_SG_REL_ \"Relation\" INT 0 1;",
        "BA_REL_ \"Relation\" BU_SG_REL_ ECU SG_ 1 Value 1;",
        "SGTYPE_ Type : 8@1+ (1,0) [0|255] \"\" 0, Table;",
        "SIG_TYPE_REF_ 1 Value : Type;",
        "EV_ Environment : 0 [0|1] \"\" 0 1 DUMMY_NODE_VECTOR0 ECU;",
        "ENVVAR_DATA_ Environment : 4;",
        "VAL_TABLE_ Table 0 \"Off\" 1 \"On\";",
        "BO_TX_BU_ 1 : ECU;", "VENDOR_EXTENSION_ data;", "UNKNOWN_"
    };
    for (const std::string &statement : statements) {
        fixture.Write(definitions + statement + '\n');
        const DbcParseResult result = DbcParser().ParseFileWithDiagnostics(fixture.path.string());
        CHECK(!result.HasErrors(), statement);
        QCOMPARE(result.diagnostics.size(), std::size_t(1U));
        const DbcDiagnostic &warning = result.diagnostics[0];
        CHECK(warning.severity == DbcDiagnosticSeverity::Warning &&
                      warning.code == DbcDiagnosticCode::UnsupportedStatement, statement);
        QCOMPARE(warning.filePath, fixture.path.string());
        QCOMPARE(warning.lineNumber, std::size_t(5U));
        const std::string keyword = statement.substr(0U, statement.find(' '));
        CHECK(warning.message.find("'" + keyword + "'") != std::string::npos, statement);
        const DecodeDatabase runtime = DbcDecodeBuilder().Build(result.database);
        RawCanFrame raw;
        raw.canId = 1U;
        raw.data = {1U};
        const DecodedFrameValue decoded = DbcDecoder().Decode(runtime, raw);
        CHECK(decoded.valid && decoded.signals.size() == 1U && decoded.signals[0].valid,
              "Warnings preserve supported signal decoding");
        QCOMPARE(decoded.signals[0].physicalValue, 12.0);
        CHECK(decoded.signals[0].GetValueDescription() &&
                      *decoded.signals[0].GetValueDescription() == "On",
              "Warnings preserve VAL_ descriptions");
        QCOMPARE(runtime.GetFrames()[0].signals[0].comment, std::string("Signal comment"));
    }
}

void DbcParserTest::diagnosticNamespaceBoundaries() {
    Fixture fixture;
    const std::vector<std::string> endings = {
        "BS_\n", "BS_:\n", "BS_ :\n", "BU_\n", "BU_:\n", "BU_ : ECU\n",
        "BO_ 1 Frame: 1 ECU\n", "VENDOR_EXTENSION_ data;\n"
    };
    for (const std::string &ending : endings) {
        fixture.Write("NS_ :\n\tSG_MUL_VAL_\n\nBA_\n" + ending + "SIG_VALTYPE_\n");
        const DbcParseResult result = DbcParser().ParseFileWithDiagnostics(fixture.path.string());
        CHECK(!result.HasErrors(), ending);
        const std::size_t expectedWarnings = ending.find("VENDOR_") == 0U ? 2U : 1U;
        QCOMPARE(result.diagnostics.size(), expectedWarnings);
        QCOMPARE(result.diagnostics.back().lineNumber, std::size_t(6U));
        CHECK(result.diagnostics.back().message.find("SIG_VALTYPE_") != std::string::npos,
              "Unsupported keyword outside NS_ must produce a warning");
    }
    for (const std::string &definition : {std::string("BO_"), std::string("SG_")}) {
        fixture.Write("NS_:\n\tBA_\n\t" + definition + '\n');
        const DbcParseResult result = DbcParser().ParseFileWithDiagnostics(fixture.path.string());
        CHECK(result.HasErrors(), "Malformed definition ends NS_ instead of being hidden");
        QCOMPARE(result.diagnostics.size(), std::size_t(1U));
        QCOMPARE(result.diagnostics[0].lineNumber, std::size_t(3U));
    }
}

void DbcParserTest::diagnosticFormatting() {
    Fixture fixture;
    fixture.path += " with spaces";
    const DbcParser parser;
    for (const std::string &text : {std::string(), std::string(" \t\r\n\n")}) {
        fixture.Write(text);
        const DbcParseResult empty = parser.ParseFileWithDiagnostics(fixture.path.string());
        CHECK(!empty.HasErrors() && empty.diagnostics.empty() && empty.database.frames.empty(),
              "Empty and whitespace-only inputs are valid");
    }
    fixture.Write("\r\n\tVENDOR_EXTENSION_ data;\r\n\r\nUNKNOWN_");
    const std::string relativePath = std::filesystem::relative(fixture.path).string();
    const DbcParseResult warnings = parser.ParseFileWithDiagnostics(relativePath);
    CHECK(!warnings.HasErrors() && warnings.database.frames.empty(), "Warnings-only input");
    QCOMPARE(warnings.diagnostics.size(), std::size_t(2U));
    QCOMPARE(warnings.diagnostics[0].lineNumber, std::size_t(2U));
    QCOMPARE(warnings.diagnostics[1].lineNumber, std::size_t(4U));
    for (const DbcDiagnostic &warning : warnings.diagnostics)
        QCOMPARE(warning.filePath, relativePath);

    fixture.Write("UNKNOWN_ first;\nBO_ invalid Frame: 1 ECU\n"
                  "UNKNOWN_ after_error;\nSG_ broken\n");
    const DbcParseResult stopped = parser.ParseFileWithDiagnostics(relativePath);
    CHECK(stopped.HasErrors() && stopped.database.frames.empty(), "First error stops parsing");
    QCOMPARE(stopped.diagnostics.size(), std::size_t(2U));
    QCOMPARE(stopped.diagnostics[0].lineNumber, std::size_t(1U));
    QCOMPARE(stopped.diagnostics[1].lineNumber, std::size_t(2U));
    QCOMPARE(stopped.diagnostics[1].filePath, relativePath);

    fixture.Write("VAL_ 1 Missing 0 \"Off\";\nBO_ 1 Frame: 1 ECU\nUNKNOWN_ data;\n");
    const DbcParseResult deferred = parser.ParseFileWithDiagnostics(relativePath);
    CHECK(deferred.HasErrors() && deferred.database.frames.empty(), "Deferred error rejects database");
    QCOMPARE(deferred.diagnostics.size(), std::size_t(2U));
    CHECK(deferred.diagnostics[0].severity == DbcDiagnosticSeverity::Warning &&
                  deferred.diagnostics[1].severity == DbcDiagnosticSeverity::Error,
          "Deferred errors follow warnings in detection order");
    QCOMPARE(deferred.diagnostics[0].lineNumber, std::size_t(3U));
    QCOMPARE(deferred.diagnostics[1].lineNumber, std::size_t(1U));
    QCOMPARE(deferred.diagnostics[1].filePath, relativePath);
    fixture.Write("BO_ 1 Frame: 1 ECU");
    const DbcParseResult recovered = parser.ParseFileWithDiagnostics(relativePath);
    CHECK(!recovered.HasErrors() && recovered.diagnostics.empty() && recovered.database.frames.size() == 1U,
          "Same parser has clean state after errors and accepts missing final newline");
}

void DbcParserTest::validFrames() {
    Fixture fixture;
    struct ValidCase {
        const char *line;
        std::uint32_t id;
        bool extended;
        unsigned length;
    };
    const ValidCase valid[] = {
            {"BO_ 0 Frame: 0 ECU", 0U, false, 0U},
            {"BO_ 2047 Frame: 8 ECU", 2047U, false, 8U},
            {"BO_ 2048 Frame: 64 ECU", 2048U, true, 64U},
            {"BO_ 536870911 Frame: 255 ECU", 0x1FFFFFFFU, true, 255U},
            {"BO_ 2147483649 Frame: 8 ECU", 1U, true, 8U},
            {"BO_ 2684354559 Frame: 8 ECU", 0x1FFFFFFFU, true, 8U},
            {"  BO_\t256\tFrame :\t8\tECU  \r", 256U, false, 8U}};
    for (const ValidCase &test: valid) {
        fixture.Write(std::string(test.line) + '\n');
        try {
            const DbcDatabase database = DbcParser().ParseFile(fixture.path.string());
            QCOMPARE(database.frames.size(), std::size_t(1U));
            const FrameInfo &frame = database.frames[0];
            QCOMPARE(frame.name, std::string("Frame"));
            QCOMPARE(frame.canId, test.id);
            QCOMPARE(frame.isExtended, test.extended);
            QCOMPARE(static_cast<unsigned>(frame.dlc), test.length);
            QCOMPARE(frame.transmitter, std::string("ECU"));
        } catch (const std::exception &error) { CHECK(false, error.what()); }
    }
}

void DbcParserTest::invalidFrames() {
    Fixture fixture;
    const char *invalid[] = {
            "BO_ invalid", "BO_", "BO_ 1", "BO_ 1 : 8 ECU", "BO_ 1 Frame 8 ECU",
            "BO_ 1 Frame:", "BO_ 1 Frame: 8", "BO_ 1 Frame: 8 ECU extra",
            "BO_ 1 Two Names: 8 ECU", "BO_ -1 Frame: 8 ECU", "BO_ +1 Frame: 8 ECU",
            "BO_ 1x Frame: 8 ECU", "BO_ 0x123 Frame: 8 ECU", "BO_ 1.5 Frame: 8 ECU",
            "BO_ 4294967296 Frame: 8 ECU", "BO_ 999999999999999999999 Frame: 8 ECU",
            "BO_ 536870912 Frame: 8 ECU", "BO_ 1073741824 Frame: 8 ECU",
            "BO_ 2684354560 Frame: 8 ECU", "BO_ 4294967295 Frame: 8 ECU",
            "BO_ 1 Frame: -1 ECU", "BO_ 1 Frame: +8 ECU", "BO_ 1 Frame: 8x ECU",
            "BO_ 1 Frame: 8.5 ECU", "BO_ 1 Frame: 256 ECU",
            "BO_ 1 Frame: 4294967296 ECU", "BO_\tinvalid"};
    for (const char *line: invalid) {
        fixture.Write(std::string("VERSION \"test\"\n\n") + line + '\n');
        try {
            DbcParser().ParseFile(fixture.path.string());
            CHECK(false, line);
        } catch (const std::runtime_error &error) {
            const std::string prefix = fixture.path.string() + ":3: ";
            CHECK(std::string(error.what()).find(prefix) == 0U &&
                          std::string(error.what()).size() > prefix.size(),
                  line);
        }
    }
}

void DbcParserTest::duplicateFrames() {
    Fixture fixture;
    struct DuplicateCase {
        const char *firstId;
        const char *duplicateId;
        const char *message;
    };
    const DuplicateCase cases[] = {
        {"1", "1", "Duplicate standard frame CAN ID: 1"},
        {"2147483649", "2147483649", "Duplicate extended frame CAN ID: 1"},
        {"2048", "2147485696", "Duplicate extended frame CAN ID: 2048"},
        {"2147485696", "2048", "Duplicate extended frame CAN ID: 2048"},
        {"536870911", "2684354559", "Duplicate extended frame CAN ID: 536870911"}
    };
    const DbcParser parser;
    for (const DuplicateCase &test : cases) {
        fixture.Write("BO_ " + std::string(test.firstId) + " First: 8 ECU\n"
                      "BO_ 2 Other: 8 ECU\n\n"
                      "  BO_\t" + test.duplicateId + "\tSecond: 8 ECU\n");
        try {
            parser.ParseFile(fixture.path.string());
            CHECK(false, "Duplicate frame must be rejected");
        } catch (const std::runtime_error &error) {
            QCOMPARE(std::string(error.what()), fixture.path.string() + ":4: " + test.message);
        }
    }
    fixture.Write("BO_ 1 First: 8 ECU\n");
    QCOMPARE(parser.ParseFile(fixture.path.string()).frames.size(), std::size_t(1U));
}

void DbcParserTest::duplicateSignals() {
    Fixture fixture;
    const std::string first = "SG_ State : 0|8@1+ (1,0) [0|255] \"\" ECU\n";
    const std::string duplicates[] = {
        first,
        "  SG_\tState : 16|8@1+ (2,1) [0|511] \"V\" ECU\n",
        "SG_ State m1 : 16|8@1+ (1,0) [0|255] \"\" ECU\n"
    };
    for (const std::string &duplicate : duplicates) {
        fixture.Write("BO_ 1 Frame: 8 ECU\n" + first +
                      "SG_ Other : 8|8@1+ (1,0) [0|255] \"\" ECU\n\n" + duplicate);
        try {
            DbcParser().ParseFile(fixture.path.string());
            CHECK(false, "Duplicate signal must be rejected");
        } catch (const std::runtime_error &error) {
            QCOMPARE(std::string(error.what()), fixture.path.string() +
                     ":5: Duplicate signal name 'State' in frame 'Frame'.");
        }
    }
}

void DbcParserTest::distinctDefinitions() {
    Fixture fixture;
    fixture.Write("BO_ 1 Shared: 1 ECU\n"
                  "SG_ State : 0|8@1+ (1,0) [0|255] \"\" ECU\n"
                  "BO_ 2147483649 Shared: 1 ECU\n"
                  "SG_ State : 0|8@1+ (1,0) [0|255] \"\" ECU\n"
                  "BO_ 2 Shared: 2 ECU\n"
                  "SG_ State : 0|8@1+ (1,0) [0|255] \"\" ECU\n"
                  "SG_ state : 8|8@1+ (1,0) [0|255] \"\" ECU\n"
                  "CM_ BO_ 1 \"Standard\";\n"
                  "CM_ BO_ 2147483649 \"Extended\";\n"
                  "CM_ SG_ 1 State \"Standard state\";\n"
                  "CM_ SG_ 2147483649 State \"Extended state\";\n");
    const DbcDatabase parsed = DbcParser().ParseFile(fixture.path.string());
    QCOMPARE(parsed.frames.size(), std::size_t(3U));
    QCOMPARE(parsed.frames[0].canId, parsed.frames[1].canId);
    CHECK(!parsed.frames[0].isExtended && parsed.frames[1].isExtended,
          "Standard and extended frames with the same numeric ID remain distinct");
    QCOMPARE(parsed.frames[0].comment, std::string("Standard"));
    QCOMPARE(parsed.frames[1].comment, std::string("Extended"));
    QCOMPARE(parsed.frames[0].signals[0].comment, std::string("Standard state"));
    QCOMPARE(parsed.frames[1].signals[0].comment, std::string("Extended state"));
    QCOMPARE(parsed.frames[2].signals.size(), std::size_t(2U));
    const DecodeDatabase runtime = DbcDecodeBuilder().Build(parsed);
    RawCanFrame raw;
    raw.canId = 1U;
    raw.data = {7U};
    const DecodedFrameValue standard = DbcDecoder().Decode(runtime, raw);
    QVERIFY(standard.valid);
    QCOMPARE(standard.definition->comment, std::string("Standard"));
    raw.isExtended = true;
    const DecodedFrameValue extended = DbcDecoder().Decode(runtime, raw);
    QVERIFY(extended.valid);
    QCOMPARE(extended.definition->comment, std::string("Extended"));
}

void DbcParserTest::comments() {
    Fixture fixture;
    fixture.Write(
            "CM_\tBO_\t1\t\"First\";\r\n"
            "CM_\tSG_\t1\tState\t\"  Line one  \r\n"
            "\r\n"
            "\tBO_ is text; \\\"quoted\\\" and \\\\slash\"\t;\r\n"
            "CM_ BO_ 2147483649 \"Extended\";\r\n"
            "CM_ SG_ 2147483649 State \"Extended signal\";\r\n"
            "BO_ 1 Standard: 1 ECU\r\n"
            "CM_ BO_ 1 \"Last\";\r\n"
            "SG_ State : 0|8@1+ (1,0) [0|255] \"\" ECU\r\n"
            "BO_ 2147483649 Extended: 1 ECU\r\n"
            "SG_ State : 0|8@1+ (1,0) [0|255] \"\" ECU");
    const DbcParseResult result = DbcParser().ParseFileWithDiagnostics(fixture.path.string());
    QVERIFY(!result.HasErrors());
    QVERIFY(result.diagnostics.empty());
    QCOMPARE(result.database.frames.size(), std::size_t(2));
    QCOMPARE(result.database.frames[0].comment, std::string("Last"));
    QCOMPARE(result.database.frames[0].signals[0].comment,
             std::string("  Line one  \n\n\tBO_ is text; \"quoted\" and \\slash"));
    QCOMPARE(result.database.frames[1].comment, std::string("Extended"));
    QCOMPARE(result.database.frames[1].signals[0].comment, std::string("Extended signal"));

    const std::string ids[][2] = {
            {"0", "0"},
            {"2047", "2047"},
            {"2048", "2147485696"},
            {"536870911", "2684354559"},
            {"2684354559", "536870911"}};
    for (const std::string(&id)[2]: ids) {
        fixture.Write("CM_ BO_ " + id[0] + " \"Frame\";\nCM_ SG_ " + id[0] +
                      " State \"Signal\";\nBO_ " + id[1] + " Frame: 1 ECU\n"
                                                           "SG_ State : 0|8@1+ (1,0) [0|255] \"\" ECU\n");
        const DbcDatabase database = DbcParser().ParseFile(fixture.path.string());
        QCOMPARE(database.frames[0].comment, std::string("Frame"));
        QCOMPARE(database.frames[0].signals[0].comment, std::string("Signal"));
    }
    fixture.Write("CM_ BO_ 1 \"Line one\nLine two\";\n"
                  "BO_ 1 Frame: 0 ECU\nUNKNOWN_ value\nBO_ bad Frame: 0 ECU\n");
    const DbcParseResult following = DbcParser().ParseFileWithDiagnostics(fixture.path.string());
    QVERIFY(following.HasErrors());
    QCOMPARE(following.diagnostics.size(), std::size_t(2));
    QCOMPARE(following.diagnostics[0].lineNumber, std::size_t(4));
    QCOMPARE(following.diagnostics[1].lineNumber, std::size_t(5));
}

void DbcParserTest::invalidComments_data() {
    QTest::addColumn<QString>("statement");
    const char *ids[] = {"-1", "+1", "1x", "0x1", "4294967296", "536870912",
                         "1073741824", "2684354560", "4294967295"};
    for (const char *id: ids) {
        const std::string frameRow = std::string("frame-id-") + id;
        const std::string signalRow = std::string("signal-id-") + id;
        QTest::newRow(frameRow.c_str()) << QString::fromStdString("CM_ BO_ " + std::string(id) + " \"Text\";");
        QTest::newRow(signalRow.c_str()) << QString::fromStdString("CM_ SG_ " + std::string(id) + " State \"Text\";");
    }
    QTest::newRow("missing-id") << QStringLiteral("CM_ BO_");
    QTest::newRow("missing-signal") << QStringLiteral("CM_ SG_ 1 \"Text\";");
    QTest::newRow("missing-quote") << QStringLiteral("CM_ BO_ 1 Text;");
    QTest::newRow("unclosed") << QStringLiteral("CM_ SG_ 1 State \"Text\n  More");
    QTest::newRow("invalid-escape") << QStringLiteral("CM_ BO_ 1 \"bad\\q\";");
    QTest::newRow("dangling-escape") << QStringLiteral("CM_ BO_ 1 \"bad\\");
    QTest::newRow("missing-semicolon") << QStringLiteral("CM_ SG_ 1 State \"Text\"");
    QTest::newRow("trailing-text") << QStringLiteral("CM_ BO_ 1 \"Text\"; garbage");
    QTest::newRow("extra-header") << QStringLiteral("CM_ BO_ 1 extra \"Text\";");
    QTest::newRow("extra-string") << QStringLiteral("CM_ BO_ 1 \"Text\" \"More\";");
    QTest::newRow("missing-frame") << QStringLiteral("CM_ BO_ 2 \"Text\";");
    QTest::newRow("missing-signal-frame") << QStringLiteral("CM_ SG_ 2 State \"Text\";");
    QTest::newRow("missing-signal-reference") << QStringLiteral("CM_ SG_ 1 Missing \"Text\";");
    QTest::newRow("different-frame-type") << QStringLiteral("CM_ BO_ 2147483649 \"Text\";");
    QTest::newRow("missing-multiline-reference") << QStringLiteral("CM_ SG_ 1 Missing \"Text\nMore\";");
}

void DbcParserTest::invalidComments() {
    QFETCH(QString, statement);
    Fixture fixture;
    fixture.Write("BO_ 1 Frame: 1 ECU\nSG_ State : 0|8@1+ (1,0) [0|255] \"\" ECU\n\n" +
                  statement.toStdString());
    const DbcParseResult result = DbcParser().ParseFileWithDiagnostics(fixture.path.string());
    QVERIFY(result.HasErrors());
    QVERIFY(result.database.frames.empty());
    QCOMPARE(result.diagnostics.size(), std::size_t(1));
    const DbcDiagnostic &error = result.diagnostics[0];
    QCOMPARE(error.severity, DbcDiagnosticSeverity::Error);
    QCOMPARE(error.code, DbcDiagnosticCode::InvalidStatement);
    QCOMPARE(error.filePath, fixture.path.string());
    QCOMPARE(error.lineNumber, std::size_t(4));
    QVERIFY(!error.message.empty());
    try {
        DbcParser().ParseFile(fixture.path.string());
        QFAIL("Malformed or unresolved comment must throw.");
    } catch (const std::runtime_error &exception) {
        QVERIFY(std::string(exception.what()).find(fixture.path.string() + ":4: ") == 0U);
    }
}

void DbcParserTest::integration() {
    Fixture fixture;
    fixture.Write(
            "BO_TX_BU_ 256 : ECU;\nBO_ 256 Frame: 8 ECU\n"
            " SG_ Speed : 0|16@1+ (0.5,1) [0|100] \"rpm\" ECU\n"
            "CM_ BO_ 256 \"Frame comment\";\nCM_ SG_ 256 Speed \"Signal comment\";\n"
            "BO_ 257 Second: 8 ECU\n");
    const DbcDatabase database = DbcParser().ParseFile(fixture.path.string());
    CHECK(database.frames.size() == 2U && database.frames[0].signals.size() == 1U &&
                  database.frames[0].comment == "Frame comment" &&
                  database.frames[0].signals[0].comment == "Signal comment",
          "Integration");
    fixture.Write("\nSG_ Speed : invalid\n");
    try {
        DbcParser().ParseFile(fixture.path.string());
        CHECK(false, "Signal error location");
    } catch (const std::runtime_error &error) {
        CHECK(std::string(error.what()).find(fixture.path.string() + ":2: ") == 0U,
              "Signal error location");
    }
}

void DbcParserTest::multiplexing() {
    Fixture fixture;
    const std::string selector = "SG_ Mode M : 0|8@1+ (10,3) [0|255] \"\" ECU\n";
    const std::string first = "SG_ First m1 : 8|8@1- (2,0) [-128|127] \"V\" ECU\n";
    const std::string second = "SG_ Second m2 : 15|8@0+ (1,0) [0|255] \"\" ECU\n";
    const std::string common = "SG_ Common : 16|8@1+ (1,0) [0|255] \"\" ECU\n";
    fixture.Write("BO_ 1 Frame: 3 ECU\n" + first + second + common + selector +
                  "VAL_ 1 First -1 \"Negative\";\n");
    const DbcDatabase parsed = DbcParser().ParseFile(fixture.path.string());
    const DecodeDatabase runtime = DbcDecodeBuilder().Build(parsed);
    CHECK(parsed.frames[0].signals[3].multiplexing.role == MultiplexRole::Selector,
          "Selector declared after branches");
    const std::unique_ptr<TreeNode> tree = DbcTreeBuilder().Build(parsed);
    CHECK(tree->GetChild(0U)->GetChild(0U)->GetSignal()->multiplexing.value == 1U,
          "Tree preserves multiplexing");
    RawCanFrame raw;
    raw.canId = 1U;
    raw.data = {1U, 255U, 7U};
    DecodedFrameValue result = DbcDecoder().Decode(runtime, raw);
    CHECK(result.signals[0].valid && std::get<std::int64_t>(result.signals[0].rawValue) == -1 &&
                  result.signals[0].physicalValue == -2 && *result.signals[0].GetValueDescription() == "Negative",
          "Active signed branch and VAL_ use exact raw selector");
    CHECK(!result.signals[1].valid && result.signals[1].status == SignalDecodeStatus::Inactive &&
                  result.signals[1].GetValueDescription() == nullptr && result.signals[2].valid,
          "Inactive branch and unconditional signal");
    raw.data[0] = 2U;
    result = DbcDecoder().Decode(runtime, raw);
    CHECK(result.signals[0].status == SignalDecodeStatus::Inactive && result.signals[1].valid &&
                  std::get<std::uint64_t>(result.signals[1].rawValue) == 255U,
          "Motorola branch becomes active");
    raw.data = {3U};
    result = DbcDecoder().Decode(runtime, raw);
    CHECK(result.signals[0].status == SignalDecodeStatus::Inactive &&
                  result.signals[1].status == SignalDecodeStatus::Inactive &&
                  result.signals[2].status == SignalDecodeStatus::InsufficientPayload,
          "Unmapped selector leaves branches inactive even with missing bytes");
    raw.data = {1U};
    result = DbcDecoder().Decode(runtime, raw);
    CHECK(result.signals[0].status == SignalDecodeStatus::InsufficientPayload,
          "Active branch requires payload");
    raw.data.clear();
    result = DbcDecoder().Decode(runtime, raw);
    CHECK(result.signals[0].status == SignalDecodeStatus::SelectorUnavailable &&
                  result.signals[3].status == SignalDecodeStatus::InsufficientPayload,
          "Unavailable selector does not imply inactive branch");

    const std::vector<std::string> invalid = {
        first,
        selector + "SG_ Other M : 16|8@1+ (1,0) [0|255] \"\" ECU\n",
        "SG_ Mode M : 0|8@1- (1,0) [-128|127] \"\" ECU\n",
        selector + "SG_ TooLarge m256 : 8|8@1+ (1,0) [0|255] \"\" ECU\n",
        selector + first + "SG_ Same m1 : 15|8@0+ (1,0) [0|255] \"\" ECU\n",
        selector + "SG_ Collision m1 : 0|8@1+ (1,0) [0|255] \"\" ECU\n",
        selector + first + "SG_ Always : 8|8@1+ (1,0) [0|255] \"\" ECU\n",
        "SG_MUL_VAL_ 1 First Mode 1-2;\n"
    };
    for (const std::string &signals : invalid) {
        fixture.Write("BO_ 1 Frame: 3 ECU\n" + signals);
        bool rejected = false;
        try {
            DbcParser().ParseFile(fixture.path.string());
        } catch (const std::runtime_error &error) {
            rejected = std::string(error.what()).find(fixture.path.string() + ":") == 0U;
        }
        CHECK(rejected, "Invalid multiplexing rejected with location");
    }
    for (const std::string marker : {"m", "m-1", "m+1", "m1M", "m18446744073709551616", "M m1"})
        RejectSignal(fixture, "SG_ Bad " + marker + " : 8|8@1+ (1,0) [0|255] \"\" ECU");
}

void DbcParserTest::multiplexingBoundaries() {
    Fixture fixture;
    fixture.Write("BO_ 1 Frame: 9 ECU\n"
                  "SG_ Branch m18446744073709551615 : 64|8@1+ (1,0) [0|255] \"\" ECU\n"
                  "SG_ Mode M : 7|64@0+ (0,5) [0|1] \"\" ECU\n");
    const DbcDatabase parsed = DbcParser().ParseFile(fixture.path.string());
    DecodeDatabase runtime = DbcDecodeBuilder().Build(parsed);
    CHECK(runtime.GetFrames()[0].signals[0].multiplexing.value == std::numeric_limits<std::uint64_t>::max(),
          "Exact uint64 branch metadata");
    RawCanFrame raw;
    raw.canId = 1U;
    raw.data = std::vector<std::uint8_t>(9U, 255U);
    DecodedFrameValue result = DbcDecoder().Decode(runtime, raw);
    CHECK(result.signals[0].valid && result.signals[1].valid &&
                  std::get<std::uint64_t>(result.signals[1].rawValue) == std::numeric_limits<std::uint64_t>::max(),
          "Motorola uint64 selector compares raw value before zero scaling");
    raw.data[7] = 254U;
    result = DbcDecoder().Decode(runtime, raw);
    CHECK(result.signals[0].status == SignalDecodeStatus::Inactive,
          "Adjacent large integers remain distinct");
    std::vector<DecodeFrame> definitions = runtime.GetFrames();
    definitions[0].signals[1].length = 0U;
    QVERIFY_THROWS_EXCEPTION(std::invalid_argument, runtime = DecodeDatabase(definitions));
    definitions[0].signals.pop_back();
    QVERIFY_THROWS_EXCEPTION(std::invalid_argument, runtime = DecodeDatabase(definitions));
    fixture.Write("BO_ 1 Frame: 2 ECU\n\n"
                  "SG_ Branch m2 : 8|8@1+ (1,0) [0|255] \"\" ECU\n"
                  "SG_ Mode M : 0|1@1+ (1,0) [0|1] \"\" ECU\n");
    bool rejected = false;
    try {
        DbcParser().ParseFile(fixture.path.string());
    } catch (const std::runtime_error &error) {
        rejected = std::string(error.what()).find(fixture.path.string() + ":3: ") == 0U;
    }
    CHECK(rejected, "Deferred validation reports branch source line");
    fixture.Write("BO_ 1 Frame: 2 ECU\n"
                  "SG_ A : 8|8@1+ (1,0) [0|255] \"\" ECU\n"
                  "SG_ B : 15|8@0+ (1,0) [0|255] \"\" ECU\n");
    rejected = false;
    try {
        DbcParser().ParseFile(fixture.path.string());
    } catch (const std::runtime_error &) {
        rejected = true;
    }
    CHECK(rejected, "Ordinary overlapping signals rejected");
}

void DbcParserTest::invalidSignals() {
    Fixture fixture;
    const std::string ordinary = SignalLine("0", "8", "1+", "1", "0", "0", "255");
    for (const std::string value: {"-1", "+1", "0junk", "0x10", "1.5",
                                   "4294967296", "999999999999999999999"}) {
        RejectSignal(fixture, SignalLine(value, "8", "1+", "1", "0", "0", "255"));
        RejectSignal(fixture, SignalLine("0", value, "1+", "1", "0", "0", "255"));
    }
    for (const std::string length: {"0", "65"})
        RejectSignal(fixture, SignalLine("0", length, "1+", "1", "0", "0", "255"));
    for (const std::string order: {"2+", "9-", "1", "1x", "1++", "01+"})
        RejectSignal(fixture, SignalLine("0", "8", order, "1", "0", "0", "255"));
    for (const std::string value: {"1junk", "nan", "NaN", "inf", "-inf", "1e999", "1e-999", "0x1p2", "", "1e", "1.2.3"}) {
        RejectSignal(fixture, SignalLine("0", "8", "1+", value, "0", "0", "255"));
        RejectSignal(fixture, SignalLine("0", "8", "1+", "1", value, "0", "255"));
        RejectSignal(fixture, SignalLine("0", "8", "1+", "1", "0", value, "255"));
        RejectSignal(fixture, SignalLine("0", "8", "1+", "1", "0", "0", value));
    }
    RejectSignal(fixture, SignalLine("0", "8", "1+", "1", "0", "2", "1"));
    for (const std::string name: {"", "Two Names", "Value m1M"}) {
        std::string line = ordinary;
        line.replace(4U, 5U, name);
        RejectSignal(fixture, line);
    }
    for (const std::string broken: {
                 "SG_", "SG_ Value", "SG_ Value : 0|8@1+ (1,0) [0|255] ECU",
                 "SG_ Value : 0|8@1+ (1,0) [0|255] \"\"",
                 "SG_ Value : 0|8@1+ (1,0) [0|255] \"\" ECU,",
                 "SG_ Value : 0|8@1+ (1,0) [0|255] \"\" ECU extra"})
        RejectSignal(fixture, broken);
    RejectSignal(fixture, SignalLine("64", "1", "1+", "1", "0", "0", "1"));
    RejectSignal(fixture, SignalLine("63", "2", "1+", "1", "0", "0", "3"));
    RejectSignal(fixture, SignalLine("56", "2", "0+", "1", "0", "0", "3"));
    RejectSignal(fixture, SignalLine("4294967295", "64", "1+", "1", "0", "0", "1"));
    RejectSignal(fixture, ordinary, 0U);
    for (const char delimiter: {'|', '@', '(', ')', '[', ']', '"'}) {
        std::string line = ordinary;
        line.erase(line.find(delimiter), 1U);
        RejectSignal(fixture, line);
    }
}

void DbcParserTest::validSignals() {
    Fixture fixture;
    const DbcParser signalParser;
    fixture.Write("BO_ 1 Frame: 8 ECU\n" +
                  SignalLine("0", "8", "1+", "0", "0", "0", "0") + "\n" +
                  SignalLine("8", "8", "1-", "-1", "0", "-255", "0", "Negative") + "\n");
    const DbcDatabase factors = signalParser.ParseFile(fixture.path.string());
    CHECK(factors.frames[0].signals.size() == 2U &&
                  factors.frames[0].signals[0].factor == 0.0 &&
                  factors.frames[0].signals[1].factor == -1.0,
          "Zero and negative factors and equal range boundaries");

    struct SignalCase {
        const char *start;
        const char *length;
        const char *order;
        unsigned payload;
    };
    const SignalCase validSignals[] = {
            {"0", "1", "1+", 1U},
            {"7", "1", "0-", 1U},
            {"0", "64", "1+", 8U},
            {"7", "64", "0-", 8U},
            {"63", "1", "1+", 8U},
            {"56", "1", "0+", 8U},
            {"3", "12", "0+", 2U},
            {"2039", "1", "1+", 255U}};
    for (const SignalCase &test: validSignals) {
        fixture.Write("BO_ 1 Frame: " + std::to_string(test.payload) + " ECU\n" +
                      SignalLine(test.start, test.length, test.order, ".5e+1", "-2.5E-1", "-1.", "+2e2") + "\n");
        try {
            const DbcDatabase parsed = signalParser.ParseFile(fixture.path.string());
            const SignalInfo &signal = parsed.frames.at(0).signals.at(0);
            QCOMPARE(signal.startBit, static_cast<std::uint32_t>(std::stoul(test.start)));
            QCOMPARE(signal.length, static_cast<std::uint32_t>(std::stoul(test.length)));
            QCOMPARE(signal.isLittleEndian, test.order[0] == '1');
            QCOMPARE(signal.isSigned, test.order[1] == '-');
            QCOMPARE(signal.factor, 5.0);
            QCOMPARE(signal.offset, -0.25);
            QCOMPARE(signal.minimum, -1.0);
            QCOMPARE(signal.maximum, 200.0);
        } catch (const std::exception &error) { CHECK(false, error.what()); }
    }
    fixture.Write("BO_ 1 Frame: 8 ECU\n"
                  "SG_\tValue\t:\t0 | 8 @1+ ( 1 , 0 ) [ 0 | 255 ] \"rpm\" ECU1,\tECU2\n");
    try {
        const DbcDatabase parsed = signalParser.ParseFile(fixture.path.string());
        const SignalInfo &signal = parsed.frames.at(0).signals.at(0);
        CHECK(signal.name == "Value" && signal.unit == "rpm" &&
                      signal.receivers == std::vector<std::string>({"ECU1", "ECU2"}),
              "Signal tabs, spaces, and receiver list");
    } catch (const std::exception &error) { CHECK(false, error.what()); }
}

void DbcParserTest::CheckPhysicalNumbers() {
    Fixture fixture;
    struct PhysicalCase {
        const char *factor;
        const char *offset;
        const char *minimum;
        const char *maximum;
        double expectedFactor;
        double expectedOffset;
        double expectedMinimum;
        double expectedMaximum;
    };
    const PhysicalCase valid[] = {
            {"+1.25", "-0.5", "-2.75", "255.5", 1.25, -0.5, -2.75, 255.5},
            {"+.5e+1", "-2.5E-1", "-1.", "+2e2", 5.0, -0.25, -1.0, 200.0},
            {"0e-999", "+0.", "-.0", ".0e+999", 0.0, 0.0, 0.0, 0.0},
            {"1.7976931348623157e308", "2.2250738585072014e-308", "-1e308", "+1e308",
             std::numeric_limits<double>::max(), std::numeric_limits<double>::min(), -1e308, 1e308}};
    for (const PhysicalCase &test: valid) {
        fixture.Write("BO_ 1 Frame: 1 ECU\n" +
                      SignalLine("0", "8", "1+", test.factor, test.offset, test.minimum, test.maximum) + "\n");
        const DbcParseResult result = DbcParser().ParseFileWithDiagnostics(fixture.path.string());
        QVERIFY(!result.HasErrors());
        QVERIFY(result.diagnostics.empty());
        QCOMPARE(result.database.frames.size(), std::size_t(1));
        const SignalInfo &signal = result.database.frames[0].signals[0];
        QCOMPARE(signal.factor, test.expectedFactor);
        QCOMPARE(signal.offset, test.expectedOffset);
        QCOMPARE(signal.minimum, test.expectedMinimum);
        QCOMPARE(signal.maximum, test.expectedMaximum);
    }

    const char *invalid[] = {"1,5", "1.234,5", "1,234.5", "1junk", "nan", "inf", "-inf",
                             "1e999", "1e-999", "1e-320", "-1e-320", "0x1p2", "1e", "1.2.3"};
    for (const char *value: invalid) {
        RejectSignal(fixture, SignalLine("0", "8", "1+", value, "0", "0", "255"));
        RejectSignal(fixture, SignalLine("0", "8", "1+", "1", value, "0", "255"));
        RejectSignal(fixture, SignalLine("0", "8", "1+", "1", "0", value, "255"));
        RejectSignal(fixture, SignalLine("0", "8", "1+", "1", "0", "0", value));
    }
    RejectSignal(fixture, SignalLine("0", "8", "1+", "1.25", "0", "2.5", "1.5"));
}

void DbcParserTest::physicalNumbersCppLocale() {
    const ApplicationLocaleGuard guard;
    std::locale::global(std::locale(std::locale::classic(), new CommaDecimalPunctuation));
    QCOMPARE(std::use_facet<std::numpunct<char>>(std::locale()).decimal_point(), ',');
    CheckPhysicalNumbers();
    QCOMPARE(std::use_facet<std::numpunct<char>>(std::locale()).decimal_point(), ',');
}

void DbcParserTest::physicalNumbersCLocale() {
    const ApplicationLocaleGuard guard;
    bool found = false;
    const char *names[] = {"de_DE.UTF-8", "de_DE.utf8", "fr_FR.UTF-8", "fr_FR.utf8",
                           "German_Germany.1252", "French_France.1252"};
    for (const char *name: names) {
        if (std::setlocale(LC_NUMERIC, name) && std::string(std::localeconv()->decimal_point) == ",") {
            found = true;
            break;
        }
    }
    if (!found)
        QSKIP("No named comma-decimal C locale is installed; generate de_DE.UTF-8 and set LOCPATH.");
    QCOMPARE(std::string(std::localeconv()->decimal_point), std::string(","));
    CheckPhysicalNumbers();
    QCOMPARE(std::string(std::localeconv()->decimal_point), std::string(","));
}

void DbcParserTest::dispatch() {
    CountingHandler::instances = 0;
    CountingHandler::calls = 0;
    DbcDatabase dispatchDatabase;
    DbcParseContext context{dispatchDatabase, nullptr};
    DbcStatementDispatcher dispatcher;
    dispatcher.RegisterType<CountingHandler>("TEST_");
    CHECK(dispatcher.Dispatch("TEST_ first", context) &&
                  dispatcher.Dispatch("TEST_ second", context) &&
                  CountingHandler::instances == 1 && CountingHandler::calls == 2 &&
                  dispatchDatabase.frames.size() == 2U,
          "Factory dispatch and handler reuse");
    CHECK(!dispatcher.Dispatch("TEST_OTHER data", context) &&
                  !dispatcher.Dispatch("BO_TX_BU_ 1 : ECU;", context) &&
                  !dispatcher.Dispatch("VAL_TABLE_ States 0 \"Stopped\";", context) &&
                  CountingHandler::calls == 2,
          "Exact and unknown keyword dispatch");
}

void DbcParserTest::independentSessions() {
    Fixture fixture;
    const DbcParser parser;
    fixture.Write("BO_ 1 First: 8 ECU\n");
    CHECK(parser.ParseFile(fixture.path.string()).frames.size() == 1U, "First parse");
    fixture.Write("SG_ Speed : invalid\n");
    try {
        parser.ParseFile(fixture.path.string());
        CHECK(false, "Independent parse context");
    } catch (const std::runtime_error &error) {
        CHECK(std::string(error.what()).find("Signal found before any frame") !=
                      std::string::npos,
              "Independent parse context");
    }
    fixture.Write("BO_ 2 Second: 8 ECU\n");
    const DbcDatabase recovered = parser.ParseFile(fixture.path.string());
    CHECK(recovered.frames.size() == 1U && recovered.frames[0].canId == 2U,
          "Fresh parse after error");
}


void DbcParserTest::valueDescriptions() {
    Fixture fixture;
    fixture.Write(
            "VAL_\t256\tState\t0\t\"Off\"\t1 \"On\" 2 \"Error with spaces; and \\\"quotes\\\"\";\n"
            "BO_ 256 Status: 8 ECU\n"
            "SG_ State : 0|8@1+ (2,10) [0|520] \"\" ECU\n"
            "VAL_ 256 State 3 \"\";\n"
            "VAL_ 2147483904 State -9223372036854775808 \"Minimum\" -1 \"Negative\" 9223372036854775807 \"Maximum\";\n"
            "BO_ 2147483904 Extended: 8 ECU\n"
            "SG_ State : 0|64@1- (1,0) [-1e20|1e20] \"\" ECU\n"
            "BO_ 2048 Unsigned: 8 ECU\n"
            "SG_ State : 0|64@1+ (1,0) [0|2e20] \"\" ECU\n"
            "VAL_ 2147485696 State 9223372036854775808 \"High\" 18446744073709551615 \"Full\";\n");
    const DbcDatabase parsed = DbcParser().ParseFile(fixture.path.string());
    const DecodeDatabase runtime = DbcDecodeBuilder().Build(parsed);
    const std::unique_ptr<TreeNode> tree = DbcTreeBuilder().Build(parsed);
    CHECK(tree->GetChild(0)->GetSignal() == nullptr, "Frame node");
    for (std::size_t index = 0; index < parsed.frames.size(); ++index) {
        CHECK(tree->GetChild(index)->GetChild(0)->GetSignal()->valueDescriptions ==
                              parsed.frames[index].signals[0].valueDescriptions &&
                      runtime.GetFrames()[index].signals[0].valueDescriptions ==
                              parsed.frames[index].signals[0].valueDescriptions,
              "All mappings survive both builders");
    }
    CHECK(tree->GetChild(0)->GetChild(0)->GetSignal()->valueDescriptions ==
                  runtime.GetFrames()[0].signals[0].valueDescriptions,
          "Both builders preserve descriptions");
    RawCanFrame frame;
    frame.canId = 256;
    frame.data.resize(8);
    const std::string expected[] = {"Off", "On", "Error with spaces; and \"quotes\"", ""};
    for (unsigned value = 0; value < 5; ++value) {
        frame.data[0] = value;
        const DecodedSignalValue decoded = DbcDecoder().Decode(runtime, frame).signals[0];
        CHECK(decoded.valid && decoded.physicalValue == value * 2 + 10, "Numeric scaling unchanged");
        const std::string *description = decoded.GetValueDescription();
        CHECK(value < 4 ? description && *description == expected[value] : !description,
              "Raw lookup and unknown value");
    }
    frame.isExtended = true;
    struct Boundary {
        std::uint64_t bits;
        const char *description;
    };
    for (const Boundary &test: {Boundary{0x8000000000000000ULL, "Minimum"},
                            Boundary{0xFFFFFFFFFFFFFFFFULL, "Negative"},
                            Boundary{0x7FFFFFFFFFFFFFFFULL, "Maximum"}}) {
        for (unsigned byte = 0; byte < 8; ++byte)
            frame.data[byte] = static_cast<std::uint8_t>(test.bits >> (byte * 8));
        const DecodedSignalValue decoded = DbcDecoder().Decode(runtime, frame).signals[0];
        CHECK(decoded.GetValueDescription() && *decoded.GetValueDescription() == test.description,
              "Signed boundaries and distinct extended frame");
    }
    frame.canId = 2048;
    for (const Boundary &test: {Boundary{0x8000000000000000ULL, "High"},
                            Boundary{0xFFFFFFFFFFFFFFFFULL, "Full"}}) {
        for (unsigned byte = 0; byte < 8; ++byte)
            frame.data[byte] = static_cast<std::uint8_t>(test.bits >> (byte * 8));
        const DecodedSignalValue decoded = DbcDecoder().Decode(runtime, frame).signals[0];
        CHECK(decoded.GetValueDescription() && *decoded.GetValueDescription() == test.description,
              "Unsigned boundaries");
    }
    CHECK(FindValueDescription(runtime.GetFrames()[0].signals[0].valueDescriptions, std::int64_t(1)) != nullptr,
          "Nonnegative signed lookup matches unsigned key");
    frame.data.clear();
    CHECK(!DbcDecoder().Decode(runtime, frame).signals[0].GetValueDescription(), "Invalid decode has no description");
}

void DbcParserTest::invalidValueDescriptions() {
    Fixture fixture;
    const std::string definitions = "BO_ 1 Frame: 8 ECU\nSG_ State : 0|64@1+ (1,0) [0|2e20] \"\" ECU\n";
    for (const std::string statement: {
                 "VAL_", "VAL_ 1 State;", "VAL_ 1 State ;", "VAL_ 1 State 0 \"Off\"",
                 "VAL_ 1 State 0 \"Off\"; junk", "VAL_ 1 State 0 Off;",
                 "VAL_ 1 State 0 \"Unclosed;", "VAL_ 1 State 0 \"Off\"1 \"On\";",
                 "VAL_ 1 State 0 \"Off\" 00 \"Duplicate\";",
                 "VAL_ 1 State 0 \"Off\" -0 \"Duplicate\";",
                 "VAL_ 1 State 0 \"Off\";\nVAL_ 1 State 0 \"Duplicate\";",
                 "VAL_ 2 State 0 \"Missing frame\";", "VAL_ 1 Missing 0 \"Missing signal\";",
                 "VAL_ -1 State 0 \"Bad ID\";", "VAL_ 536870912 State 0 \"Bad ID\";",
                 "VAL_ 4294967296 State 0 \"Bad ID\";", "VAL_ Environment 0 \"Unsupported\";",
                 "VAL_ 1 State 0 \"Bad\\q escape\";"}) {
        fixture.Write(definitions + statement + '\n');
        const int line = statement.find('\n') == std::string::npos ? 3 : 4;
        try {
            DbcParser().ParseFile(fixture.path.string());
            CHECK(false, statement);
        } catch (const std::runtime_error &error) {
            CHECK(std::string(error.what()).find(fixture.path.string() + ":" + std::to_string(line) + ": ") == 0,
                  statement + " " + error.what());
        }
    }
    for (const std::string suffix: {
                 "BO_ 1 Other: 8 ECU\n",                       // Duplicate frame definition.
                 "SG_ State : 0|8@1+ (1,0) [0|255] \"\" ECU\n",// Duplicate signal definition.
                 ""}) {
        fixture.Write("VAL_ 1 " + std::string(suffix.empty() ? "Missing" : "State") +
                      " 0 \"Description\";\n" + definitions + suffix);
        try {
            DbcParser().ParseFile(fixture.path.string());
            CHECK(false, "Missing reference or duplicate definition");
        } catch (const std::runtime_error &error) {
            const std::string line = suffix.empty() ? "1" : "4";
            CHECK(std::string(error.what()).find(fixture.path.string() + ":" + line + ": ") == 0,
                  "Error retains the reference or duplicate definition source location");
        }
    }
    for (const std::string number: {"+1", "1x", "0x10", "1.5", "1e2", "--1",
                                    "-9223372036854775809", "18446744073709551616"}) {
        fixture.Write("VAL_ 1 State " + number + " \"Bad\";\n" + definitions);
        try {
            DbcParser().ParseFile(fixture.path.string());
            CHECK(false, number);
        } catch (const std::runtime_error &error) {
            CHECK(std::string(error.what()).find(fixture.path.string() + ":1: ") == 0, number);
        }
    }
}

int RunParserTests(int argc, char **argv) {
    DbcParserTest tests;
    return QTest::qExec(&tests, argc, argv);
}

#include "dbc_parser_test.moc"