// 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_BANJO_COMPILER_TEST_LIBRARY_H_
#define ZIRCON_SYSTEM_UTEST_BANJO_COMPILER_TEST_LIBRARY_H_

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

static banjo::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 banjo::SourceFile(filename, source_code);
}

class TestLibrary {
public:
    TestLibrary(const std::string& raw_source_code)
        : TestLibrary("example.banjo", raw_source_code) {}

    TestLibrary(const std::string& filename, const std::string& raw_source_code)
        : source_file_(MakeSourceFile(filename, raw_source_code)),
          lexer_(source_file_, &identifier_table_),
          parser_(&lexer_, &error_reporter_),
          library_(std::make_unique<banjo::flat::Library>(&all_libraries_, &error_reporter_)) {
    }

    bool AddDependentLibrary(TestLibrary& dependent_library) {
        // For testing, we have conveniences to construct compiled test
        // libraries, which we usurp here to move it into the current library
        // under test. This would be made clearer with a helper object which
        // owned all libraries under test.
        if (!all_libraries_.Insert(std::unique_ptr<banjo::flat::Library>(dependent_library.library_.get()))) {
            return false;
        }
        dependent_library.library_.release();
        return true;
    }

    bool Parse(std::unique_ptr<banjo::raw::File>& ast_ptr) {
        ast_ptr.reset(parser_.Parse().release());
        return parser_.Ok();
    }

    bool Compile() {
        auto ast = parser_.Parse();
        return parser_.Ok() &&
               library_->ConsumeFile(std::move(ast)) &&
               library_->Compile();
    }

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

    bool AddSourceFile(const std::string& filename, const std::string& raw_source_code) {
        auto source_file = MakeSourceFile(filename, raw_source_code);
        banjo::IdentifierTable identifier_table;
        banjo::Lexer lexer(source_file, &identifier_table);
        banjo::Parser parser(&lexer, &error_reporter_);
        auto ast = parser.Parse();
        return parser.Ok() &&
               library_->ConsumeFile(std::move(ast)) &&
               library_->Compile();
    }

    const banjo::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 banjo::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 banjo::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;
    }

    banjo::SourceFile source_file() {
        return source_file_;
    }

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

private:
    banjo::SourceFile source_file_;
    banjo::IdentifierTable identifier_table_;
    banjo::ErrorReporter error_reporter_;
    banjo::Lexer lexer_;
    banjo::Parser parser_;
    banjo::flat::Libraries all_libraries_;
    std::unique_ptr<banjo::flat::Library> library_;
};

#endif // ZIRCON_SYSTEM_UTEST_BANJO_COMPILER_TEST_LIBRARY_H_