// Native console client. RSSRV owns the logical console; this file speaks its Port protocol.

#include <ntlite/console_service.h>
#include <ntlite/port.h>
#include <ntlite/resource.h>
#include <ntlite/syscall.h>
#include <intrin.h>
#include <string.h>

static volatile long gDefaultConsoleSession;
static KSTATUS NtlConsoleGetDefaultSession(SYS_HANDLE* sessionOut);

// Connects to RSSRV's native console service.
KSTATUS NtlConsoleConnect(SYS_HANDLE* sessionOut) {
    if (!sessionOut) return NTLSTATUS_INVALID_PARAMETER;
    *sessionOut = SYS_HANDLE_INVALID;

    SYS_HANDLE resourceSession = SYS_HANDLE_INVALID;
    KSTATUS status = NtlResourceConnect(&resourceSession);
    if (!KSUCCESS(status)) return status;

    SYS_HANDLE listener = SYS_HANDLE_INVALID;
    status = NtlResourceLookup(resourceSession, SYS_SV_LITERAL(NTL_CONSOLE_SERVICE_PATH),
                               SYS_RIGHT_QUERY | SYS_PORT_RIGHT_CONNECT, &listener);
    (void)NtlResourceClose(resourceSession);
    if (!KSUCCESS(status)) return status;

    status = NtlResourceConnectListener(listener, sessionOut);
    (void)SysCloseHandle(listener);
    return status;
}

// Disconnects one console service session.
KSTATUS NtlConsoleClose(SYS_HANDLE session) {
    if (session == SYS_HANDLE_INVALID) return NTLSTATUS_INVALID_PARAMETER;
    (void)SysDisconnectPort(session);
    return SysCloseHandle(session);
}

// Returns one process-local cached console session.
static KSTATUS NtlConsoleGetDefaultSession(SYS_HANDLE* sessionOut) {
    if (!sessionOut) return NTLSTATUS_INVALID_PARAMETER;
    long current = gDefaultConsoleSession;
    if (current != 0) {
        *sessionOut = (SYS_HANDLE)(uint32_t)current;
        return NTLSTATUS_SUCCESS;
    }

    SYS_HANDLE created = SYS_HANDLE_INVALID;
    KSTATUS status = NtlConsoleConnect(&created);
    if (!KSUCCESS(status)) return status;

    long previous = _InterlockedCompareExchange(&gDefaultConsoleSession, (long)created, 0);
    if (previous != 0) {
        (void)NtlConsoleClose(created);
        created = (SYS_HANDLE)(uint32_t)previous;
    }
    *sessionOut = created;
    return NTLSTATUS_SUCCESS;
}

// Executes one fixed console request and validates the reply envelope.
static KSTATUS NtlConsoleCall(SYS_HANDLE session,
                              const NTL_CONSOLE_REQUEST* request,
                              NTL_CONSOLE_REPLY* replyOut) {
    if (!request || !replyOut) return NTLSTATUS_INVALID_PARAMETER;
    if (session == SYS_HANDLE_INVALID) {
        KSTATUS status = NtlConsoleGetDefaultSession(&session);
        if (!KSUCCESS(status)) return status;
    }

    NTL_CONSOLE_REPLY reply;
    memset(&reply, 0, sizeof(reply));
    SYS_PORT_MESSAGE_INFO info;
    memset(&info, 0, sizeof(info));
    info.Size = sizeof(info);

    SYS_CALL_PORT_REQUEST call;
    memset(&call, 0, sizeof(call));
    call.Size = sizeof(call);
    call.EndpointHandle = session;
    call.Flags = SYS_PORT_FLAG_NONE;
    call.RequestPayload = request;
    call.RequestLength = sizeof(*request);
    call.ReplyPayload = &reply;
    call.ReplyCapacity = sizeof(reply);
    call.ReplyInfoOut = &info;
    call.TimeoutMilliseconds = SYS_PORT_TIMEOUT_INFINITE;
    KSTATUS status = SysCallPort(&call);
    if (!KSUCCESS(status)) return status;

    if (info.Type != SYS_PORT_MESSAGE_REPLY || info.PayloadLength != sizeof(reply) || info.HandleCount != 0 ||
        reply.Size != sizeof(reply) || reply.Version != NTL_CONSOLE_PROTOCOL_VERSION ||
        reply.Operation != request->Operation || reply.Flags != NTL_CONSOLE_FLAG_NONE)
        return NTLSTATUS_FAILURE;
    *replyOut = reply;
    return reply.Status;
}

// Writes arbitrary bytes to the console in bounded protocol chunks.
KSTATUS NtlConsoleWrite(SYS_HANDLE session, const void* data, size_t length, size_t* writtenOut) {
    if (writtenOut) *writtenOut = 0;
    if (length && !data) return NTLSTATUS_INVALID_PARAMETER;
    const char* bytes = (const char*)data;
    size_t total = 0;
    while (total < length) {
        size_t chunk = length - total;
        if (chunk > NTL_CONSOLE_WRITE_MAX) chunk = NTL_CONSOLE_WRITE_MAX;
        NTL_CONSOLE_REQUEST request;
        memset(&request, 0, sizeof(request));
        request.Size = sizeof(request);
        request.Version = NTL_CONSOLE_PROTOCOL_VERSION;
        request.Operation = NTL_CONSOLE_OP_WRITE;
        request.Flags = NTL_CONSOLE_FLAG_NONE;
        request.Data.Write.Length = (uint32_t)chunk;
        memcpy(request.Data.Write.Data, bytes + total, chunk);
        NTL_CONSOLE_REPLY reply;
        memset(&reply, 0, sizeof(reply));
        KSTATUS status = NtlConsoleCall(session, &request, &reply);
        total += reply.Written;
        if (!KSUCCESS(status) || reply.Written != chunk) {
            if (writtenOut) *writtenOut = total;
            return KSUCCESS(status) ? NTLSTATUS_FAILURE : status;
        }
    }
    if (writtenOut) *writtenOut = total;
    return NTLSTATUS_SUCCESS;
}

// Queries the logical console's current dimensions and cursor state.
KSTATUS NtlConsoleQueryInfo(SYS_HANDLE session, NTL_CONSOLE_INFO* infoOut) {
    if (!infoOut) return NTLSTATUS_INVALID_PARAMETER;
    NTL_CONSOLE_REQUEST request;
    memset(&request, 0, sizeof(request));
    request.Size = sizeof(request);
    request.Version = NTL_CONSOLE_PROTOCOL_VERSION;
    request.Operation = NTL_CONSOLE_OP_QUERY_INFO;
    NTL_CONSOLE_REPLY reply;
    KSTATUS status = NtlConsoleCall(session, &request, &reply);
    if (KSUCCESS(status)) *infoOut = reply.Info;
    return status;
}

// Executes one console operation whose reply has only status and optional written count.
static KSTATUS NtlConsoleSimpleCall(SYS_HANDLE session, NTL_CONSOLE_REQUEST* request,
                                    uint32_t* writtenOut) {
    NTL_CONSOLE_REPLY reply;
    memset(&reply, 0, sizeof(reply));
    KSTATUS status = NtlConsoleCall(session, request, &reply);
    if (writtenOut) *writtenOut = reply.Written;
    return status;
}

// Updates the logical console cursor.
KSTATUS NtlConsoleSetCursor(SYS_HANDLE session, int x, int y) {
    NTL_CONSOLE_REQUEST request;
    memset(&request, 0, sizeof(request));
    request.Size = sizeof(request);
    request.Version = NTL_CONSOLE_PROTOCOL_VERSION;
    request.Operation = NTL_CONSOLE_OP_SET_CURSOR;
    request.Data.Cursor.X = x;
    request.Data.Cursor.Y = y;
    return NtlConsoleSimpleCall(session, &request, 0);
}

// Fills console characters over one linear cell range.
KSTATUS NtlConsoleFillCharacter(SYS_HANDLE session, char character, int x, int y,
                                size_t length, size_t* writtenOut) {
    if (writtenOut) *writtenOut = 0;
    if (length > UINT32_MAX) return NTLSTATUS_INVALID_PARAMETER;
    NTL_CONSOLE_REQUEST request;
    memset(&request, 0, sizeof(request));
    request.Size = sizeof(request);
    request.Version = NTL_CONSOLE_PROTOCOL_VERSION;
    request.Operation = NTL_CONSOLE_OP_FILL_CHARACTER;
    request.Data.FillCharacter.Character = character;
    request.Data.FillCharacter.X = x;
    request.Data.FillCharacter.Y = y;
    request.Data.FillCharacter.Length = (uint32_t)length;
    uint32_t written = 0;
    KSTATUS status = NtlConsoleSimpleCall(session, &request, &written);
    if (writtenOut) *writtenOut = written;
    return status;
}

// Fills console attributes over one linear cell range.
KSTATUS NtlConsoleFillAttribute(SYS_HANDLE session, uint16_t attribute, int x, int y,
                                size_t length, size_t* writtenOut) {
    if (writtenOut) *writtenOut = 0;
    if (length > UINT32_MAX) return NTLSTATUS_INVALID_PARAMETER;
    NTL_CONSOLE_REQUEST request;
    memset(&request, 0, sizeof(request));
    request.Size = sizeof(request);
    request.Version = NTL_CONSOLE_PROTOCOL_VERSION;
    request.Operation = NTL_CONSOLE_OP_FILL_ATTRIBUTE;
    request.Data.FillAttribute.Attribute = attribute;
    request.Data.FillAttribute.X = x;
    request.Data.FillAttribute.Y = y;
    request.Data.FillAttribute.Length = (uint32_t)length;
    uint32_t written = 0;
    KSTATUS status = NtlConsoleSimpleCall(session, &request, &written);
    if (writtenOut) *writtenOut = written;
    return status;
}

// Draws one glyph at explicit pixel coordinates without moving console state.
KSTATUS NtlConsolePutCharacter(SYS_HANDLE session, char character, int x, int y,
                               uint32_t foreground, uint32_t background) {
    NTL_CONSOLE_REQUEST request;
    memset(&request, 0, sizeof(request));
    request.Size = sizeof(request);
    request.Version = NTL_CONSOLE_PROTOCOL_VERSION;
    request.Operation = NTL_CONSOLE_OP_PUT_CHARACTER;
    request.Data.PutCharacter.Character = character;
    request.Data.PutCharacter.X = x;
    request.Data.PutCharacter.Y = y;
    request.Data.PutCharacter.Foreground = foreground;
    request.Data.PutCharacter.Background = background;
    return NtlConsoleSimpleCall(session, &request, 0);
}

// Clears the console's current display target.
KSTATUS NtlConsoleClear(SYS_HANDLE session, uint32_t color) {
    NTL_CONSOLE_REQUEST request;
    memset(&request, 0, sizeof(request));
    request.Size = sizeof(request);
    request.Version = NTL_CONSOLE_PROTOCOL_VERSION;
    request.Operation = NTL_CONSOLE_OP_CLEAR;
    request.Data.Clear.Color = color;
    return NtlConsoleSimpleCall(session, &request, 0);
}

// Executes one console input operation and returns its key record.
static KSTATUS NtlConsoleInputCall(SYS_HANDLE session, uint32_t operation,
                                   uint64_t timeoutMilliseconds, INPUT_KEY_RECORD* recordOut) {
    NTL_CONSOLE_REQUEST request;
    memset(&request, 0, sizeof(request));
    request.Size = sizeof(request);
    request.Version = NTL_CONSOLE_PROTOCOL_VERSION;
    request.Operation = operation;
    request.TimeoutMilliseconds = timeoutMilliseconds;
    NTL_CONSOLE_REPLY reply;
    KSTATUS status = NtlConsoleCall(session, &request, &reply);
    if (KSUCCESS(status) && recordOut) *recordOut = reply.Input;
    return status;
}

// Reads one logical console input record.
KSTATUS NtlConsoleReadInput(SYS_HANDLE session, uint64_t timeoutMilliseconds,
                            INPUT_KEY_RECORD* recordOut) {
    if (!recordOut) return NTLSTATUS_INVALID_PARAMETER;
    return NtlConsoleInputCall(session, NTL_CONSOLE_OP_READ_INPUT, timeoutMilliseconds, recordOut);
}

// Peeks one logical console input record.
KSTATUS NtlConsolePeekInput(SYS_HANDLE session, uint64_t timeoutMilliseconds,
                            INPUT_KEY_RECORD* recordOut) {
    if (!recordOut) return NTLSTATUS_INVALID_PARAMETER;
    return NtlConsoleInputCall(session, NTL_CONSOLE_OP_PEEK_INPUT, timeoutMilliseconds, recordOut);
}

// Discards every queued logical console input record.
KSTATUS NtlConsoleFlushInput(SYS_HANDLE session) {
    NTL_CONSOLE_REQUEST request;
    memset(&request, 0, sizeof(request));
    request.Size = sizeof(request);
    request.Version = NTL_CONSOLE_PROTOCOL_VERSION;
    request.Operation = NTL_CONSOLE_OP_FLUSH_INPUT;
    return NtlConsoleSimpleCall(session, &request, 0);
}

// Reads until one console key record has a character representation.
KSTATUS NtlConsoleReadCharacter(SYS_HANDLE session, char* characterOut) {
    if (!characterOut) return NTLSTATUS_INVALID_PARAMETER;
    for (;;) {
        INPUT_KEY_RECORD record;
        KSTATUS status = NtlConsoleReadInput(session, SYS_PORT_TIMEOUT_INFINITE, &record);
        if (!KSUCCESS(status)) return status;
        if (record.Char != 0) {
            *characterOut = record.Char;
            return NTLSTATUS_SUCCESS;
        }
    }
}