// Copyright Contributors to the Open Shading Language project.
// SPDX-License-Identifier: BSD-3-Clause
// https://github.com/AcademySoftwareFoundation/OpenShadingLanguage

#pragma once

#include "osl_pvt.h"
#include <OSL/platform.h>

#include <OpenImageIO/string_view.h>
#include <OpenImageIO/thread.h>



OSL_NAMESPACE_ENTER

namespace pvt {

// Turn off warnings about unused params, since we have lots of declarations
// with stub function bodies.
OSL_PRAGMA_WARNING_PUSH
OSL_GCC_PRAGMA(GCC diagnostic ignored "-Wunused-parameter")


/// Base class for OSO (OpenShadingLanguage object code) file reader.
///
class OSOReader {
public:
    OSOReader(ErrorHandler* errhandler = NULL)
        : m_err(errhandler ? *errhandler : ErrorHandler::default_handler())
        , m_lineno(1)
    {
    }
    virtual ~OSOReader() {}

    /// Read in the oso file, parse it, call the various callbacks.
    /// Return true if the file was correctly parsed, false if there was
    /// an unrecoverable error reading the file.
    virtual bool parse_file(const std::string& filename);

    /// Read in OSO from memory, parse, call the various callbacks.
    /// Return true if the OSO code was correctly parsed, false if there was
    /// an unrecoverable error reading.
    virtual bool parse_memory(const std::string& buffer);

    /// Declare the shader version.
    ///
    virtual void version(const char* specid, int major, int minor) {}

    /// Set the name and type of the shader
    ///
    virtual void shader(const char* shadertype, const char* name) {}

    /// Register a new symbol.
    ///
    virtual void symbol(SymType symtype, TypeSpec typespec, const char* name) {}

    /// Add a default integer value to the last declared symbol.
    ///
    virtual void symdefault(int def) {}

    /// Add a default float value to the last declared symbol.
    ///
    virtual void symdefault(float def) {}

    /// Add a default string value to the last declared symbol.
    ///
    virtual void symdefault(const char* def) {}

    /// Called when we're done with all information related to a parameter
    /// symbol.
    virtual void parameter_done() {}

    /// Return true for parsers whose only purpose is to read the header up
    /// to params, to stop parsing as soon as we start encountering temps in
    /// the symbol table.
    virtual bool stop_parsing_at_temp_symbols() { return false; }

    /// Add a hint.
    ///
    virtual void hint(string_view hintstring) {}

    /// Return true if this parser cares about the code, false if parsing
    /// of oso may terminate once the symbol table has been parsed.
    virtual bool parse_code_section() { return true; }

    /// New code section marker designating subsequent instructions.
    ///
    virtual void codemarker(const char* name) {}

    /// Mark the end of the code section
    ///
    virtual void codeend() {}

    /// Add an instruction.
    ///
    virtual void instruction(int label, const char* opcode) {}

    /// Add an argument to the last instruction.
    ///
    virtual void instruction_arg(const char* name) {}

    /// Add a jump target to the last instruction.
    ///
    virtual void instruction_jump(int target) {}

    /// Called after an instruction (after args and hints)
    ///
    virtual void instruction_end() {}

    /// Increment the line number (for error reporting).  Should only
    /// be called by the lexer.
    void incr_lineno() { ++m_lineno; }

    /// Return the line number (for error reporting).  Should only
    /// be called by the lexer.
    int lineno() const { return m_lineno; }

    /// Return a reference to the error handler
    ErrorHandler& errhandler() { return m_err; }

    /// Store and retrieve the current typespec
    ///
    void current_typespec(TypeSpec t) { m_current_typespec = std::move(t); }
    TypeSpec current_typespec() const { return m_current_typespec; }

private:
    class Scope;
    ErrorHandler& m_err;
    int m_lineno;
    TypeSpec m_current_typespec;
};

OSL_PRAGMA_WARNING_POP


};  // namespace pvt
OSL_NAMESPACE_EXIT
