// Copyright 2018 The Fuchsia Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef ZIRCON_SYSTEM_UTEST_FIDL_COMPILER_TEST_LIBRARY_H_
#define ZIRCON_SYSTEM_UTEST_FIDL_COMPILER_TEST_LIBRARY_H_

#include <fidl/flat_ast.h>
#include <fidl/json_generator.h>
#include <fidl/lexer.h>
#include <fidl/linter.h>
#include <fidl/parser.h>
#include <fidl/source_file.h>

static std::unique_ptr<fidl::SourceFile> MakeSourceFile(const std::string& filename,
                                                        const std::string& raw_source_code) {
    std::string source_code(raw_source_code);
    // NUL terminate the string.
    source_code.resize(source_code.size() + 1);
    return std::make_unique<fidl::SourceFile>(filename, source_code);
}

class SharedAmongstLibraries {
public:
    SharedAmongstLibraries()
        : typespace(fidl::flat::Typespace::RootTypes(&error_reporter)) {}

    fidl::ErrorReporter error_reporter;
    fidl::flat::Typespace typespace;
    fidl::flat::Libraries all_libraries;
    std::vector<std::unique_ptr<fidl::SourceFile>> all_sources_of_all_libraries;
};

class TestLibrary final {
public:
    explicit TestLibrary()
        : TestLibrary(&owned_shared_) {}

    explicit TestLibrary(SharedAmongstLibraries* shared)
        : error_reporter_(&shared->error_reporter),
          typespace_(&shared->typespace),
          all_libraries_(&shared->all_libraries),
          all_sources_of_all_libraries_(&shared->all_sources_of_all_libraries),
          library_(std::make_unique<fidl::flat::Library>(
              all_libraries_, error_reporter_, typespace_)) {}

    explicit TestLibrary(const std::string& raw_source_code)
        : TestLibrary("example.fidl", raw_source_code) {}

    TestLibrary(const std::string& filename, const std::string& raw_source_code)
        : TestLibrary(filename, raw_source_code, &owned_shared_) {}

    TestLibrary(const std::string& filename, const std::string& raw_source_code,
                SharedAmongstLibraries* shared)
        : TestLibrary(shared) {
        AddSource(filename, raw_source_code);
    }

    void AddSource(const std::string& filename, const std::string& raw_source_code) {
        auto source_file = MakeSourceFile(filename, raw_source_code);
        all_sources_.push_back(source_file.get());
        all_sources_of_all_libraries_->push_back(std::move(source_file));
    }

    bool AddDependentLibrary(TestLibrary dependent_library) {
        return all_libraries_->Insert(std::move(dependent_library.library_));
    }

    void AddAttributeSchema(const std::string& name, fidl::flat::AttributeSchema schema) {
        all_libraries_->AddAttributeSchema(name, std::move(schema));
    }

    // TODO(pascallouis): remove, this does not use a library.
    bool Parse(std::unique_ptr<fidl::raw::File>* out_ast_ptr) {
        assert(all_sources_.size() == 1 && "parse can only be used with one source");
        auto source_file = all_sources_.at(0);
        fidl::Lexer lexer(*source_file, error_reporter_);
        fidl::Parser parser(&lexer, error_reporter_);
        out_ast_ptr->reset(parser.Parse().release());
        return parser.Ok();
    }

    bool Compile() {
        for (auto source_file : all_sources_) {
            fidl::Lexer lexer(*source_file, error_reporter_);
            fidl::Parser parser(&lexer, error_reporter_);
            auto ast = parser.Parse();
            if (!parser.Ok())
                return false;
            if (!library_->ConsumeFile(std::move(ast)))
                return false;
        }
        return library_->Compile();
    }

    // TODO(pascallouis): remove, this does not use a library.
    bool Lint(fidl::Findings* findings) {
        assert(all_sources_.size() == 1 && "lint can only be used with one source");
        auto source_file = all_sources_.at(0);
        fidl::Lexer lexer(*source_file, error_reporter_);
        fidl::Parser parser(&lexer, error_reporter_);
        auto ast = parser.Parse();
        if (!parser.Ok()) {
            std::string_view beginning(source_file->data().data(), 0);
            fidl::SourceLocation source_location(beginning, *source_file);
            findings->emplace_back(source_location, "parser-error",
                                   error_reporter_->errors().front() + "\n");
            return false;
        }
        fidl::linter::Linter linter;
        return linter.Lint(ast, findings);
    }

    bool Lint() {
        fidl::Findings findings;
        bool passed = Lint(&findings);
        fidl::utils::WriteFindingsToErrorReporter(findings, error_reporter_);
        return passed;
    }

    std::string GenerateJSON() {
        auto json_generator = fidl::JSONGenerator(library_.get());
        auto out = json_generator.Produce();
        return out.str();
    }

    const fidl::flat::Bits* LookupBits(const std::string& name) {
        for (const auto& bits_decl : library_->bits_declarations_) {
            if (bits_decl->GetName() == name) {
                return bits_decl.get();
            }
        }
        return nullptr;
    }

    const fidl::flat::Const* LookupConstant(const std::string& name) {
        for (const auto& const_decl : library_->const_declarations_) {
            if (const_decl->GetName() == name) {
                return const_decl.get();
            }
        }
        return nullptr;
    }

    const fidl::flat::Struct* LookupStruct(const std::string& name) {
        for (const auto& struct_decl : library_->struct_declarations_) {
            if (struct_decl->GetName() == name) {
                return struct_decl.get();
            }
        }
        return nullptr;
    }

    const fidl::flat::Table* LookupTable(const std::string& name) {
        for (const auto& table_decl : library_->table_declarations_) {
            if (table_decl->GetName() == name) {
                return table_decl.get();
            }
        }
        return nullptr;
    }

    const fidl::flat::Union* LookupUnion(const std::string& name) {
        for (const auto& union_decl : library_->union_declarations_) {
            if (union_decl->GetName() == name) {
                return union_decl.get();
            }
        }
        return nullptr;
    }

    const fidl::flat::XUnion* LookupXUnion(const std::string& name) {
        for (const auto& xunion_decl : library_->xunion_declarations_) {
            if (xunion_decl->GetName() == name) {
                return xunion_decl.get();
            }
        }
        return nullptr;
    }

    const fidl::flat::Interface* LookupInterface(const std::string& name) {
        for (const auto& interface_decl : library_->interface_declarations_) {
            if (interface_decl->GetName() == name) {
                return interface_decl.get();
            }
        }
        return nullptr;
    }

    void set_warnings_as_errors(bool value) {
        error_reporter_->set_warnings_as_errors(value);
    }

    const fidl::flat::Library* library() const {
        return library_.get();
    }

    const fidl::SourceFile& source_file() const {
        assert(all_sources_.size() == 1 && "convenience method only possible with single source");
        return *all_sources_.at(0);
    }

    fidl::SourceLocation SourceLocation(size_t start, size_t size) const {
        assert(all_sources_.size() == 1 && "convenience method only possible with single source");
        std::string_view data = all_sources_.at(0)->data();
        data.remove_prefix(start);
        data.remove_suffix(data.size() - size);
        return fidl::SourceLocation(data, *all_sources_.at(0));
    }

    const std::vector<std::string>& errors() const {
        return error_reporter_->errors();
    }

    const std::vector<std::string>& warnings() const {
        return error_reporter_->warnings();
    }

    const std::vector<fidl::flat::Decl*> declaration_order() const {
        return library_->declaration_order_;
    }

protected:
    SharedAmongstLibraries owned_shared_;
    fidl::ErrorReporter* error_reporter_;
    fidl::flat::Typespace* typespace_;
    fidl::flat::Libraries* all_libraries_;
    std::vector<std::unique_ptr<fidl::SourceFile>>* all_sources_of_all_libraries_;
    std::vector<fidl::SourceFile*> all_sources_;
    std::unique_ptr<fidl::flat::Library> library_;
};

#endif // ZIRCON_SYSTEM_UTEST_FIDL_COMPILER_TEST_LIBRARY_H_