/*
 * Copyright (c) 2020-2021, Linus Groh <mail@linusgroh.de>
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * 1. Redistributions of source code must retain the above copyright notice, this
 *    list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright notice,
 *    this list of conditions and the following disclaimer in the documentation
 *    and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
 * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#include <AK/LexicalPath.h>
#include <AK/StringBuilder.h>
#include <AK/Types.h>
#include <AK/URL.h>
#include <Applications/CrashReporter/CrashReporterWindowGML.h>
#include <LibCore/ArgsParser.h>
#include <LibCoreDump/Backtrace.h>
#include <LibCoreDump/Reader.h>
#include <LibDesktop/AppFile.h>
#include <LibDesktop/Launcher.h>
#include <LibELF/CoreDump.h>
#include <LibGUI/Application.h>
#include <LibGUI/BoxLayout.h>
#include <LibGUI/Button.h>
#include <LibGUI/FileIconProvider.h>
#include <LibGUI/Icon.h>
#include <LibGUI/ImageWidget.h>
#include <LibGUI/Label.h>
#include <LibGUI/LinkLabel.h>
#include <LibGUI/TabWidget.h>
#include <LibGUI/TextEditor.h>
#include <LibGUI/Widget.h>
#include <LibGUI/Window.h>
#include <string.h>

struct TitleAndText {
    String title;
    String text;
};

static TitleAndText build_backtrace(const CoreDump::Reader& coredump, const ELF::Core::ThreadInfo& thread_info, size_t thread_index)
{
    CoreDump::Backtrace backtrace(coredump, thread_info);

    StringBuilder builder;

    auto prepend_assertion = [&] {
        auto assertion = coredump.metadata().get("assertion");
        if (!assertion.has_value() || assertion.value().is_empty())
            return;
        builder.append("ASSERTION FAILED: ");
        builder.append(assertion.value().characters());
        builder.append('\n');
        builder.append('\n');
    };

    auto first_entry = true;
    for (auto& entry : backtrace.entries()) {
        if (first_entry) {
            if (entry.function_name.starts_with("__assertion_failed"))
                prepend_assertion();
            first_entry = false;
        } else {
            builder.append('\n');
        }
        builder.append(entry.to_string());
    }

    return {
        String::formatted("Thread #{} (TID {})", thread_index, thread_info.tid),
        builder.build()
    };
}

int main(int argc, char** argv)
{
    if (pledge("stdio sendfd shared_buffer accept cpath rpath unix fattr", nullptr) < 0) {
        perror("pledge");
        return 1;
    }

    const char* coredump_path = nullptr;

    Core::ArgsParser args_parser;
    args_parser.set_general_help("Show information from an application crash coredump.");
    args_parser.add_positional_argument(coredump_path, "Coredump path", "coredump-path");
    args_parser.parse(argc, argv);

    Vector<TitleAndText> thread_backtraces;

    String executable_path;
    int pid { 0 };
    u8 termination_signal { 0 };

    {
        auto coredump = CoreDump::Reader::create(coredump_path);
        if (!coredump) {
            warnln("Could not open coredump '{}'", coredump_path);
            return 1;
        }

        size_t thread_index = 0;
        coredump->for_each_thread_info([&](auto& thread_info) {
            thread_backtraces.append(build_backtrace(*coredump, thread_info, thread_index));
            ++thread_index;
            return IterationDecision::Continue;
        });

        executable_path = coredump->process_executable_path();
        pid = coredump->process_pid();
        termination_signal = coredump->process_termination_signal();
    }

    auto app = GUI::Application::construct(argc, argv);

    if (pledge("stdio sendfd shared_buffer accept rpath unix", nullptr) < 0) {
        perror("pledge");
        return 1;
    }

    if (unveil(executable_path.characters(), "r") < 0) {
        perror("unveil");
        return 1;
    }

    if (unveil("/res", "r") < 0) {
        perror("unveil");
        return 1;
    }

    if (unveil("/tmp/portal/launch", "rw") < 0) {
        perror("unveil");
        return 1;
    }

    if (unveil(nullptr, nullptr) < 0) {
        perror("unveil");
        return 1;
    }

    auto app_icon = GUI::Icon::default_icon("app-crash-reporter");

    auto window = GUI::Window::construct();
    window->set_title("Crash Reporter");
    window->set_icon(app_icon.bitmap_for_size(16));
    window->resize(460, 340);
    window->center_on_screen();

    auto& widget = window->set_main_widget<GUI::Widget>();
    widget.load_from_gml(crash_reporter_window_gml);

    auto& icon_image_widget = *widget.find_descendant_of_type_named<GUI::ImageWidget>("icon");
    icon_image_widget.set_bitmap(GUI::FileIconProvider::icon_for_executable(executable_path).bitmap_for_size(32));

    auto app_name = LexicalPath(executable_path).basename();
    auto af = Desktop::AppFile::get_for_app(app_name);
    if (af->is_valid())
        app_name = af->name();

    auto& description_label = *widget.find_descendant_of_type_named<GUI::Label>("description");
    description_label.set_text(String::formatted("\"{}\" (PID {}) has crashed - {} (signal {})", app_name, pid, strsignal(termination_signal), termination_signal));

    auto& executable_link_label = *widget.find_descendant_of_type_named<GUI::LinkLabel>("executable_link");
    executable_link_label.set_text(LexicalPath::canonicalized_path(executable_path));
    executable_link_label.on_click = [&] {
        Desktop::Launcher::open(URL::create_with_file_protocol(LexicalPath(executable_path).dirname()));
    };

    auto& coredump_link_label = *widget.find_descendant_of_type_named<GUI::LinkLabel>("coredump_link");
    coredump_link_label.set_text(LexicalPath::canonicalized_path(coredump_path));
    coredump_link_label.on_click = [&] {
        Desktop::Launcher::open(URL::create_with_file_protocol(LexicalPath(coredump_path).dirname()));
    };

    auto& tab_widget = *widget.find_descendant_of_type_named<GUI::TabWidget>("tab_widget");

    auto& backtrace_tab = tab_widget.add_tab<GUI::Widget>("Backtrace");
    backtrace_tab.set_layout<GUI::VerticalBoxLayout>();
    backtrace_tab.layout()->set_margins({ 4, 4, 4, 4 });

    auto& backtrace_label = backtrace_tab.add<GUI::Label>("A backtrace for each thread alive during the crash is listed below:");
    backtrace_label.set_text_alignment(Gfx::TextAlignment::CenterLeft);
    backtrace_label.set_fixed_height(16);

    auto& backtrace_tab_widget = backtrace_tab.add<GUI::TabWidget>();
    backtrace_tab_widget.set_tab_position(GUI::TabWidget::TabPosition::Bottom);
    for (auto& backtrace : thread_backtraces) {
        auto& backtrace_text_editor = backtrace_tab_widget.add_tab<GUI::TextEditor>(backtrace.title);
        backtrace_text_editor.set_layout<GUI::VerticalBoxLayout>();
        backtrace_text_editor.layout()->set_margins({ 4, 4, 4, 4 });
        backtrace_text_editor.set_text(backtrace.text);
        backtrace_text_editor.set_mode(GUI::TextEditor::Mode::ReadOnly);
        backtrace_text_editor.set_should_hide_unnecessary_scrollbars(true);
    }

    auto& close_button = *widget.find_descendant_of_type_named<GUI::Button>("close_button");
    close_button.on_click = [&](auto) {
        app->quit();
    };

    window->show();

    return app->exec();
}