#include "displayserver_linux.h"

#ifdef FF_HAVE_XCB_RANDR

    #include "common/library.h"
    #include "common/properties.h"
    #include "common/edidHelper.h"
    #include "common/mallocHelper.h"
    #include "common/strutil.h"

    #include <stdlib.h>
    #include <string.h>
    #include <xcb/randr.h>
    #include <xcb/xcb.h>

typedef struct XcbRandrData {
    FF_LIBRARY_SYMBOL(xcb_randr_get_screen_resources_current)
    FF_LIBRARY_SYMBOL(xcb_randr_get_screen_resources_current_reply)
    FF_LIBRARY_SYMBOL(xcb_randr_get_screen_resources_current_modes_iterator)
    FF_LIBRARY_SYMBOL(xcb_randr_mode_info_next)
    FF_LIBRARY_SYMBOL(xcb_randr_get_monitors)
    FF_LIBRARY_SYMBOL(xcb_randr_get_monitors_reply)
    FF_LIBRARY_SYMBOL(xcb_randr_get_monitors_monitors_iterator)
    FF_LIBRARY_SYMBOL(xcb_randr_monitor_info_next)
    FF_LIBRARY_SYMBOL(xcb_randr_monitor_info_outputs_length)
    FF_LIBRARY_SYMBOL(xcb_randr_monitor_info_outputs)
    FF_LIBRARY_SYMBOL(xcb_randr_output_next)
    FF_LIBRARY_SYMBOL(xcb_randr_get_output_info)
    FF_LIBRARY_SYMBOL(xcb_randr_get_output_info_reply)
    FF_LIBRARY_SYMBOL(xcb_randr_get_crtc_info)
    FF_LIBRARY_SYMBOL(xcb_randr_get_crtc_info_reply)
    FF_LIBRARY_SYMBOL(xcb_randr_get_output_property)
    FF_LIBRARY_SYMBOL(xcb_randr_get_output_property_reply)
    FF_LIBRARY_SYMBOL(xcb_randr_get_output_property_data)
    FF_LIBRARY_SYMBOL(xcb_randr_get_output_property_data_length)

    FF_LIBRARY_SYMBOL(xcb_intern_atom)
    FF_LIBRARY_SYMBOL(xcb_intern_atom_reply)
    FF_LIBRARY_SYMBOL(xcb_get_property)
    FF_LIBRARY_SYMBOL(xcb_get_property_reply)
    FF_LIBRARY_SYMBOL(xcb_get_property_value)
    FF_LIBRARY_SYMBOL(xcb_get_property_value_length)
    FF_LIBRARY_SYMBOL(xcb_get_atom_name)
    FF_LIBRARY_SYMBOL(xcb_get_atom_name_name)
    FF_LIBRARY_SYMBOL(xcb_get_atom_name_name_length)
    FF_LIBRARY_SYMBOL(xcb_get_atom_name_reply)
    FF_LIBRARY_SYMBOL(xcb_get_setup)
    FF_LIBRARY_SYMBOL(xcb_setup_vendor)
    FF_LIBRARY_SYMBOL(xcb_setup_vendor_length)

    // init once
    xcb_connection_t* connection;
    FFDisplayServerResult* result;
} XcbRandrData;

static void* xcbGetProperty(XcbRandrData* data, xcb_window_t window, const char* request) {
    xcb_intern_atom_cookie_t requestAtomCookie = data->ffxcb_intern_atom(data->connection, true, (uint16_t) strlen(request), request);
    FF_AUTO_FREE xcb_intern_atom_reply_t* requestAtomReply = data->ffxcb_intern_atom_reply(data->connection, requestAtomCookie, NULL);
    if (requestAtomReply == NULL) {
        return NULL;
    }

    xcb_get_property_cookie_t propertyCookie = data->ffxcb_get_property(data->connection, false, window, requestAtomReply->atom, XCB_ATOM_ANY, 0, 8 * 1024);
    FF_AUTO_FREE xcb_get_property_reply_t* propertyReply = data->ffxcb_get_property_reply(data->connection, propertyCookie, NULL);
    if (propertyReply == NULL) {
        return NULL;
    }

    int length = data->ffxcb_get_property_value_length(propertyReply);
    if (length <= 0) {
        return NULL;
    }

    // Why are xcb property strings not null terminated???
    void* replyValue = malloc((size_t) length + 1);
    memcpy(replyValue, data->ffxcb_get_property_value(propertyReply), (size_t) length);
    ((char*) replyValue)[length] = '\0';

    return replyValue;
}

static xcb_randr_get_output_property_reply_t* xcbRandrGetProperty(XcbRandrData* data, xcb_randr_output_t output, const char* name) {
    xcb_intern_atom_cookie_t requestAtomCookie = data->ffxcb_intern_atom(data->connection, true, (uint16_t) strlen(name), name);
    FF_AUTO_FREE xcb_intern_atom_reply_t* requestAtomReply = data->ffxcb_intern_atom_reply(data->connection, requestAtomCookie, NULL);

    if (requestAtomReply) {
        xcb_randr_get_output_property_cookie_t outputPropertyCookie = data->ffxcb_randr_get_output_property(data->connection, output, requestAtomReply->atom, XCB_GET_PROPERTY_TYPE_ANY, 0, 100, false, false);
        return data->ffxcb_randr_get_output_property_reply(data->connection, outputPropertyCookie, NULL);
    }
    return NULL;
}

static void xcbDetectWMfromEWMH(XcbRandrData* data, xcb_window_t rootWindow, FFDisplayServerResult* result) {
    if (result->wmProcessName.length > 0 || ffStrbufEqualS(&result->wmProtocolName, FF_WM_PROTOCOL_WAYLAND)) {
        return;
    }

    FF_AUTO_FREE xcb_window_t* wmWindow = (xcb_window_t*) xcbGetProperty(data, rootWindow, "_NET_SUPPORTING_WM_CHECK");
    if (wmWindow == NULL) {
        return;
    }

    FF_AUTO_FREE char* wmName = (char*) xcbGetProperty(data, *wmWindow, "WM_NAME");
    if (!ffStrSet(wmName)) {
        wmName = (char*) xcbGetProperty(data, *wmWindow, "_NET_WM_NAME");
    }

    if (!ffStrSet(wmName)) {
        return;
    }

    ffStrbufSetS(&result->wmProcessName, wmName);
}

static void xcbFetchServerVendor(XcbRandrData* data, FFDisplayServerResult* result) {
    const xcb_setup_t* setup = data->ffxcb_get_setup(data->connection);

    int length = data->ffxcb_setup_vendor_length(setup);
    if (length <= 0) {
        return;
    }

    FF_STRBUF_AUTO_DESTROY serverVendor = ffStrbufCreateNS((uint32_t) length, data->ffxcb_setup_vendor(setup));

    if (!ffStrbufEqualS(&serverVendor, "The X.Org Foundation")) // Original
    {
        ffStrbufDestroy(&result->wmProtocolName);
        ffStrbufInitMove(&result->wmProtocolName, &serverVendor);
    }
}

static bool xcbRandrHandleOutput(XcbRandrData* data, xcb_randr_output_t output, FFstrbuf* name, bool primary, FFDisplayType displayType, struct xcb_randr_get_screen_resources_current_reply_t* screenResources, uint8_t bitDepth, uint32_t dpi) {
    xcb_randr_get_output_info_cookie_t outputInfoCookie = data->ffxcb_randr_get_output_info(data->connection, output, XCB_CURRENT_TIME);
    FF_AUTO_FREE xcb_randr_get_output_info_reply_t* outputInfoReply = data->ffxcb_randr_get_output_info_reply(data->connection, outputInfoCookie, NULL);
    if (outputInfoReply == NULL) {
        return false;
    }

    FF_AUTO_FREE xcb_randr_get_output_property_reply_t* edidReply = xcbRandrGetProperty(data, output, "EDID");
    uint8_t* edidData = NULL;
    uint32_t edidLength = 0;
    if (edidReply) {
        int len = data->ffxcb_randr_get_output_property_data_length(edidReply);
        if (len >= 128) {
            edidData = data->ffxcb_randr_get_output_property_data(edidReply);
            edidLength = (uint32_t) len;
        }
    }

    if (edidData) {
        ffStrbufClear(name);
        ffEdidGetName(edidData, name);
    }

    bool randrEmulation = false;
    FF_AUTO_FREE xcb_randr_get_output_property_reply_t* randrEmulationReply = xcbRandrGetProperty(data, output, "RANDR Emulation");
    if (randrEmulationReply) {
        int len = data->ffxcb_randr_get_output_property_data_length(randrEmulationReply);
        if (len >= 1) {
            randrEmulation = !!data->ffxcb_randr_get_output_property_data(randrEmulationReply)[0];
        }
    }

    xcb_randr_get_crtc_info_cookie_t crtcInfoCookie = data->ffxcb_randr_get_crtc_info(data->connection, outputInfoReply->crtc, XCB_CURRENT_TIME);
    FF_AUTO_FREE xcb_randr_get_crtc_info_reply_t* crtcInfoReply = data->ffxcb_randr_get_crtc_info_reply(data->connection, crtcInfoCookie, NULL);
    if (crtcInfoReply == NULL) {
        return false;
    }

    uint32_t rotation;
    switch (crtcInfoReply->rotation) {
        case XCB_RANDR_ROTATION_ROTATE_90:
            rotation = 90;
            break;
        case XCB_RANDR_ROTATION_ROTATE_180:
            rotation = 180;
            break;
        case XCB_RANDR_ROTATION_ROTATE_270:
            rotation = 270;
            break;
        default:
            rotation = 0;
            break;
    }

    xcb_randr_mode_info_t* currentMode = NULL;
    xcb_randr_mode_info_t* preferredMode = NULL;

    if (screenResources) {
        xcb_randr_mode_info_iterator_t modesIterator = data->ffxcb_randr_get_screen_resources_current_modes_iterator(screenResources);

        if (outputInfoReply->num_preferred > 0) {
            preferredMode = modesIterator.data;
        }

        while (modesIterator.rem > 0) {
            if (modesIterator.data->id == crtcInfoReply->mode) {
                currentMode = modesIterator.data;
                break;
            }

            data->ffxcb_randr_mode_info_next(&modesIterator);
        }
    }

    FFDisplayResult* item = ffdsAppendDisplay(
        data->result,
        (uint32_t) (currentMode ? currentMode->width : crtcInfoReply->width),
        (uint32_t) (currentMode ? currentMode->height : crtcInfoReply->height),
        currentMode ? (double) currentMode->dot_clock / (double) ((uint32_t) currentMode->htotal * currentMode->vtotal) : 0,
        dpi,
        preferredMode ? (uint32_t) preferredMode->width : 0,
        preferredMode ? (uint32_t) preferredMode->height : 0,
        preferredMode ? (double) preferredMode->dot_clock / (double) ((uint32_t) preferredMode->htotal * preferredMode->vtotal) : 0,
        rotation,
        name,
        displayType,
        primary,
        0,
        (uint32_t) outputInfoReply->mm_width,
        (uint32_t) outputInfoReply->mm_height,
        randrEmulation
            ? (currentMode ? "xcb-randr-emu-mode" : "xcb-randr-emu-crtc")
            : (currentMode ? "xcb-randr-mode" : "xcb-randr-crtc")

    );
    if (item) {
        if (edidData && edidLength >= 128) {
            item->hdrStatus = ffEdidGetHdrCompatible(edidData, (uint32_t) edidLength) ? FF_DISPLAY_HDR_STATUS_SUPPORTED : FF_DISPLAY_HDR_STATUS_UNSUPPORTED;
            ffEdidGetSerialAndManufactureDate(edidData, &item->serial, &item->manufactureYear, &item->manufactureWeek);
        }
        item->bitDepth = bitDepth;
        if ((rotation == 90 || rotation == 180) && !randrEmulation) {
            // In XWayland mode, width / height has been swapped out of box
            uint32_t tmp = item->width;
            item->width = item->height;
            item->height = tmp;
        }
    }

    return !!item;
}

static bool xcbRandrHandleMonitor(XcbRandrData* data, xcb_randr_monitor_info_t* monitor, struct xcb_randr_get_screen_resources_current_reply_t* screenResources, uint8_t bitDepth, uint32_t dpi) {
    // for some reasons, we have to construct this our self
    xcb_randr_output_iterator_t outputIterator = {
        .index = 0,
        .data = data->ffxcb_randr_monitor_info_outputs(monitor),
        .rem = data->ffxcb_randr_monitor_info_outputs_length(monitor)
    };

    FF_AUTO_FREE xcb_get_atom_name_reply_t* nameReply = data->ffxcb_get_atom_name_reply(
        data->connection,
        data->ffxcb_get_atom_name(data->connection, monitor->name),
        NULL);
    FF_STRBUF_AUTO_DESTROY name = ffStrbufCreateNS(
        (uint32_t) data->ffxcb_get_atom_name_name_length(nameReply),
        data->ffxcb_get_atom_name_name(nameReply));
    const FFDisplayType displayType = ffdsGetDisplayType(name.chars);

    bool foundOutput = false;

    while (outputIterator.rem > 0) {
        if (xcbRandrHandleOutput(data, *outputIterator.data, &name, monitor->primary, displayType, screenResources, bitDepth, dpi)) {
            foundOutput = true;
        }
        data->ffxcb_randr_output_next(&outputIterator);
    }

    if (foundOutput) {
        return true;
    }

    FFDisplayResult* display = ffdsAppendDisplay(
        data->result,
        (uint32_t) monitor->width,
        (uint32_t) monitor->height,
        0,
        dpi,
        0,
        0,
        0,
        0,
        &name,
        displayType,
        !!monitor->primary,
        0,
        (uint32_t) monitor->width_in_millimeters,
        (uint32_t) monitor->height_in_millimeters,
        "xcb-randr-monitor");
    if (display) {
        display->bitDepth = bitDepth;
    }
    return !!display;
}

static bool xcbRandrHandleMonitors(XcbRandrData* data, xcb_screen_t* screen) {
    xcb_randr_get_monitors_cookie_t monitorsCookie = data->ffxcb_randr_get_monitors(data->connection, screen->root, true);
    FF_AUTO_FREE xcb_randr_get_monitors_reply_t* monitorsReply = data->ffxcb_randr_get_monitors_reply(data->connection, monitorsCookie, NULL);
    if (monitorsReply == NULL) {
        return false;
    }

    // Init screen resources. They are used to iterate over all modes. xcbRandrHandleMode checks for " == NULL", to fail as late as possible.
    xcb_randr_get_screen_resources_current_cookie_t screenResourcesCookie = data->ffxcb_randr_get_screen_resources_current(data->connection, screen->root);
    FF_AUTO_FREE struct xcb_randr_get_screen_resources_current_reply_t* screenResources = data->ffxcb_randr_get_screen_resources_current_reply(data->connection, screenResourcesCookie, NULL);

    uint32_t dpi = 0;
    FF_AUTO_FREE const char* resourceManager = xcbGetProperty(data, screen->root, "RESOURCE_MANAGER");
    if (resourceManager) {
        FF_STRBUF_AUTO_DESTROY dpiStr = ffStrbufCreate();
        if (ffParsePropLines(resourceManager, "Xft.dpi:", &dpiStr)) {
            dpi = (uint32_t) ffStrbufToUInt(&dpiStr, 96);
        }
    }
    uint8_t bitDepth = (uint8_t) (screen->root_depth / 3);

    xcb_randr_monitor_info_iterator_t monitorInfoIterator = data->ffxcb_randr_get_monitors_monitors_iterator(monitorsReply);

    bool foundMonitor = false;

    while (monitorInfoIterator.rem > 0) {
        if (xcbRandrHandleMonitor(data, monitorInfoIterator.data, screenResources, bitDepth, dpi)) {
            foundMonitor = true;
        }
        data->ffxcb_randr_monitor_info_next(&monitorInfoIterator);
    }

    return foundMonitor;
}

static void xcbRandrHandleScreen(XcbRandrData* data, xcb_screen_t* screen) {
    // With all the initialisation done, start the detection
    if (xcbRandrHandleMonitors(data, screen)) {
        return;
    }

    // If detetction failed, fallback to screen = monitor, like in the libxcb.so implementation
    ffdsAppendDisplay(
        data->result,
        (uint32_t) screen->width_in_pixels,
        (uint32_t) screen->height_in_pixels,
        0,
        0,
        0,
        0,
        0,
        0,
        NULL,
        FF_DISPLAY_TYPE_UNKNOWN,
        false,
        (uint64_t) screen->root,
        (uint32_t) screen->width_in_millimeters,
        (uint32_t) screen->height_in_millimeters,
        "xcb-randr-screen");
}

const char* ffdsConnectXcbRandr(FFDisplayServerResult* result) {
    FF_LIBRARY_LOAD_MESSAGE(xcbRandr, "libxcb-randr" FF_LIBRARY_EXTENSION, 1)
    FF_LIBRARY_LOAD_SYMBOL_MESSAGE(xcbRandr, xcb_connect)
    FF_LIBRARY_LOAD_SYMBOL_MESSAGE(xcbRandr, xcb_connection_has_error)
    FF_LIBRARY_LOAD_SYMBOL_MESSAGE(xcbRandr, xcb_get_setup)
    FF_LIBRARY_LOAD_SYMBOL_MESSAGE(xcbRandr, xcb_setup_roots_iterator)
    FF_LIBRARY_LOAD_SYMBOL_MESSAGE(xcbRandr, xcb_screen_next)
    FF_LIBRARY_LOAD_SYMBOL_MESSAGE(xcbRandr, xcb_disconnect)

    XcbRandrData data;

    FF_LIBRARY_LOAD_SYMBOL_VAR_MESSAGE(xcbRandr, data, xcb_intern_atom)
    FF_LIBRARY_LOAD_SYMBOL_VAR_MESSAGE(xcbRandr, data, xcb_intern_atom_reply)
    FF_LIBRARY_LOAD_SYMBOL_VAR_MESSAGE(xcbRandr, data, xcb_get_property)
    FF_LIBRARY_LOAD_SYMBOL_VAR_MESSAGE(xcbRandr, data, xcb_get_property_reply)
    FF_LIBRARY_LOAD_SYMBOL_VAR_MESSAGE(xcbRandr, data, xcb_get_property_value)
    FF_LIBRARY_LOAD_SYMBOL_VAR_MESSAGE(xcbRandr, data, xcb_get_property_value_length)
    FF_LIBRARY_LOAD_SYMBOL_VAR_MESSAGE(xcbRandr, data, xcb_get_atom_name)
    FF_LIBRARY_LOAD_SYMBOL_VAR_MESSAGE(xcbRandr, data, xcb_get_atom_name_name)
    FF_LIBRARY_LOAD_SYMBOL_VAR_MESSAGE(xcbRandr, data, xcb_get_atom_name_name_length)
    FF_LIBRARY_LOAD_SYMBOL_VAR_MESSAGE(xcbRandr, data, xcb_get_atom_name_reply)
    FF_LIBRARY_LOAD_SYMBOL_VAR_MESSAGE(xcbRandr, data, xcb_get_setup)
    FF_LIBRARY_LOAD_SYMBOL_VAR_MESSAGE(xcbRandr, data, xcb_setup_vendor)
    FF_LIBRARY_LOAD_SYMBOL_VAR_MESSAGE(xcbRandr, data, xcb_setup_vendor_length)

    FF_LIBRARY_LOAD_SYMBOL_VAR_MESSAGE(xcbRandr, data, xcb_randr_get_screen_resources_current)
    FF_LIBRARY_LOAD_SYMBOL_VAR_MESSAGE(xcbRandr, data, xcb_randr_get_screen_resources_current_reply)
    FF_LIBRARY_LOAD_SYMBOL_VAR_MESSAGE(xcbRandr, data, xcb_randr_get_screen_resources_current_modes_iterator)
    FF_LIBRARY_LOAD_SYMBOL_VAR_MESSAGE(xcbRandr, data, xcb_randr_mode_info_next)
    FF_LIBRARY_LOAD_SYMBOL_VAR_MESSAGE(xcbRandr, data, xcb_randr_get_monitors)
    FF_LIBRARY_LOAD_SYMBOL_VAR_MESSAGE(xcbRandr, data, xcb_randr_get_monitors_reply)
    FF_LIBRARY_LOAD_SYMBOL_VAR_MESSAGE(xcbRandr, data, xcb_randr_get_monitors_monitors_iterator)
    FF_LIBRARY_LOAD_SYMBOL_VAR_MESSAGE(xcbRandr, data, xcb_randr_monitor_info_next)
    FF_LIBRARY_LOAD_SYMBOL_VAR_MESSAGE(xcbRandr, data, xcb_randr_monitor_info_outputs_length)
    FF_LIBRARY_LOAD_SYMBOL_VAR_MESSAGE(xcbRandr, data, xcb_randr_monitor_info_outputs)
    FF_LIBRARY_LOAD_SYMBOL_VAR_MESSAGE(xcbRandr, data, xcb_randr_output_next)
    FF_LIBRARY_LOAD_SYMBOL_VAR_MESSAGE(xcbRandr, data, xcb_randr_get_output_info)
    FF_LIBRARY_LOAD_SYMBOL_VAR_MESSAGE(xcbRandr, data, xcb_randr_get_output_info_reply)
    FF_LIBRARY_LOAD_SYMBOL_VAR_MESSAGE(xcbRandr, data, xcb_randr_get_output_property)
    FF_LIBRARY_LOAD_SYMBOL_VAR_MESSAGE(xcbRandr, data, xcb_randr_get_output_property_reply)
    FF_LIBRARY_LOAD_SYMBOL_VAR_MESSAGE(xcbRandr, data, xcb_randr_get_output_property_data)
    FF_LIBRARY_LOAD_SYMBOL_VAR_MESSAGE(xcbRandr, data, xcb_randr_get_output_property_data_length)
    FF_LIBRARY_LOAD_SYMBOL_VAR_MESSAGE(xcbRandr, data, xcb_randr_get_crtc_info)
    FF_LIBRARY_LOAD_SYMBOL_VAR_MESSAGE(xcbRandr, data, xcb_randr_get_crtc_info_reply)

    data.connection = ffxcb_connect(NULL, NULL);
    if (ffxcb_connection_has_error(data.connection) > 0) {
        ffxcb_disconnect(data.connection);
        return "xcb_connect() failed";
    }

    data.result = result;

    xcb_screen_iterator_t iterator = ffxcb_setup_roots_iterator(ffxcb_get_setup(data.connection));

    if (iterator.rem > 0) {
        xcbDetectWMfromEWMH(&data, iterator.data->root, result);
        xcbFetchServerVendor(&data, result);
    }

    while (iterator.rem > 0) {
        xcbRandrHandleScreen(&data, iterator.data);
        ffxcb_screen_next(&iterator);
    }

    ffxcb_disconnect(data.connection);

    // If wayland hasn't set this, connection failed for it. So we are running only a X Server, not XWayland.
    if (result->wmProtocolName.length == 0) {
        ffStrbufSetS(&result->wmProtocolName, FF_WM_PROTOCOL_X11);
    }

    return NULL;
}

#else

const char* ffdsConnectXcbRandr(FFDisplayServerResult* result) {
    // Do nothing. There are other implementations coming
    FF_UNUSED(result)
    return "Fastfetch was compiled without libxcb-randr support";
}

#endif