#include "buffer_manager.hh"

#include "assert.hh"
#include "buffer.hh"
#include "client_manager.hh"
#include "exception.hh"
#include "file.hh"
#include "ranges.hh"
#include "string.hh"

namespace Kakoune
{

BufferManager::~BufferManager()
{
    // Move buffers to m_buffer_trash to avoid running BufClose
    // hook while clearing m_buffers
    m_buffer_trash = std::move(m_buffers);

    for (auto& buffer : m_buffer_trash)
        buffer->on_unregistered();

    // Make sure not clients exists
    if (ClientManager::has_instance())
        ClientManager::instance().clear();
}

Buffer* BufferManager::create_buffer(String name, Buffer::Flags flags,
                                     StringView data, timespec fs_timestamp)
{
    auto path = real_path(parse_filename(name));
    for (auto& buf : m_buffers)
    {
        if (buf->name() == name or
            (buf->flags() & Buffer::Flags::File and buf->name() == path))
            throw runtime_error{"buffer name is already in use"};
    }

    m_buffers.emplace(m_buffers.begin(),
                      new Buffer{std::move(name), flags, data, fs_timestamp});
    auto& buffer = *m_buffers.front();
    buffer.on_registered();

    if (contains(m_buffer_trash, &buffer))
        throw runtime_error{"Buffer got removed during its creation"};

    return &buffer;
}

void BufferManager::delete_buffer(Buffer& buffer)
{
    auto it = find_if(m_buffers, [&](const std::unique_ptr<Buffer>& p)
                      { return p.get() == &buffer; });
    kak_assert(it != m_buffers.end());

    m_buffer_trash.emplace_back(std::move(*it));
    m_buffers.erase(it);

    if (ClientManager::has_instance())
        ClientManager::instance().ensure_no_client_uses_buffer(buffer);

    buffer.on_unregistered();
}

Buffer* BufferManager::get_buffer_ifp(StringView name)
{
    auto path = real_path(parse_filename(name));
    for (auto& buf : m_buffers)
    {
        if (buf->name() == name or
            (buf->flags() & Buffer::Flags::File and buf->name() == path))
            return buf.get();
    }
    return nullptr;
}

Buffer& BufferManager::get_buffer(StringView name)
{
    Buffer* res = get_buffer_ifp(name);
    if (not res)
        throw runtime_error{format("no such buffer '{}'", name)};
    return *res;
}

Buffer& BufferManager::get_first_buffer()
{
    if (not contains_that(m_buffers, [](const std::unique_ptr<Buffer>& p)
                          { return not (p->flags() & Buffer::Flags::Debug); }))
        create_buffer("*scratch*", Buffer::Flags::None);

    return *m_buffers.front();
}

void BufferManager::backup_modified_buffers()
{
    for (auto& buf : m_buffers)
    {
        if ((buf->flags() & Buffer::Flags::File) and buf->is_modified()
            and not (buf->flags() & Buffer::Flags::ReadOnly))
            write_buffer_to_backup_file(*buf);
    }
}

void BufferManager::clear_buffer_trash()
{
    for (auto& buffer : m_buffer_trash)
    {
        // Do that again, to be tolerant in some corner cases, where a buffer is
        // deleted during its creation
        if (ClientManager::has_instance())
        {
            ClientManager::instance().ensure_no_client_uses_buffer(*buffer);
            ClientManager::instance().clear_window_trash();
        }

        buffer.reset();
    }

    m_buffer_trash.clear();
}

}