/*
        Copyright 2007-2009 Haiku, Inc.  All rights reserved.
        Distributed under the terms of the MIT license.

        Authors:
        Gerald Zajac 2007-2009
*/

#include "accelerant.h"

#include <string.h>
#include <unistd.h>

#include <create_display_modes.h>               // common accelerant header file


static display_mode*
FindDisplayMode(int width, int height, int refreshRate, uint32 colorDepth)
{
        // Search the mode list for the mode with specified width, height,
        // refresh rate, and color depth.  If argument colorDepth is zero, this
        // function will search for a mode satisfying the other 3 arguments, and
        // if more than one matching mode is found, the one with the greatest color
        // depth will be selected.
        //
        // If successful, return a pointer to the selected display_mode object;
        // else return NULL.

        display_mode* selectedMode = NULL;
        uint32 modeCount = gInfo.sharedInfo->modeCount;

        for (uint32 j = 0; j < modeCount; j++) {
                display_mode& mode = gInfo.modeList[j];

                if (mode.timing.h_display == width && mode.timing.v_display == height) {
                        int modeRefreshRate = int(((mode.timing.pixel_clock * 1000.0 /
                                        mode.timing.h_total) / mode.timing.v_total) + 0.5);
                        if (modeRefreshRate == refreshRate) {
                                if (colorDepth == 0) {
                                        if (selectedMode == NULL || mode.space > selectedMode->space)
                                                selectedMode = &mode;
                                } else {
                                        if (mode.space == colorDepth)
                                                return &mode;
                                }
                        }
                }
        }

        return selectedMode;
}



static bool
IsThereEnoughFBMemory(const display_mode* mode, uint32 bitsPerPixel)
{
        // Test if there is enough Frame Buffer memory for the mode and color depth
        // specified by the caller, and return true if there is sufficient memory.

        uint32 maxWidth = mode->virtual_width;
        if (mode->timing.h_display > maxWidth)
                maxWidth = mode->timing.h_display;

        uint32 maxHeight = mode->virtual_height;
        if (mode->timing.v_display > maxHeight)
                maxHeight = mode->timing.v_display;

        uint32 bytesPerPixel = (bitsPerPixel + 7) / 8;

        return (maxWidth * maxHeight * bytesPerPixel < gInfo.sharedInfo->maxFrameBufferSize);
}



uint16
GetVesaModeNumber(const display_mode& mode, uint8 bitsPerPixel)
{
        // Search VESA mode table for a matching mode, and return the VESA mode
        // number if a match is found;  else return 0 if no match is found.

        SharedInfo& si = *gInfo.sharedInfo;

        VesaMode* vesaModeTable = (VesaMode*)((uint8*)&si + si.vesaModeTableOffset);

        for (uint32 j = 0; j < si.vesaModeCount; j++) {
                VesaMode& vesaMode = vesaModeTable[j];

                if (vesaMode.width == mode.timing.h_display
                        && vesaMode.height == mode.timing.v_display
                        && vesaMode.bitsPerPixel == bitsPerPixel)
                        return vesaMode.mode;
        }

        return 0;               // matching VESA mode not found
}



bool
IsModeUsable(const display_mode* mode)
{
        // Test if the display mode is usable by the current video chip.  That is,
        // does the chip have enough memory for the mode and is the pixel clock
        // within the chips allowable range, etc.
        //
        // Return true if the mode is usable.

        SharedInfo& si = *gInfo.sharedInfo;
        uint8 bitsPerPixel;
        uint32 maxPixelClock;

        if (!gInfo.GetColorSpaceParams(mode->space, bitsPerPixel, maxPixelClock))
                return false;

        // Is there enough frame buffer memory to handle the mode?

        if (!IsThereEnoughFBMemory(mode, bitsPerPixel))
                return false;

        if (si.displayType == MT_VGA) {
                // Test if mode is usable for a chip that is connected to a monitor
                // via an analog VGA connector.

                if (mode->timing.pixel_clock > maxPixelClock)
                        return false;

                // Is the color space supported?

                bool colorSpaceSupported = false;
                for (uint32 j = 0; j < si.colorSpaceCount; j++) {
                        if (mode->space == uint32(si.colorSpaces[j])) {
                                colorSpaceSupported = true;
                                break;
                        }
                }

                if (!colorSpaceSupported)
                        return false;

                // Reject modes with a width of 640 and a height < 480 since they do not
                // work properly with the ATI chipsets.

                if (mode->timing.h_display == 640 && mode->timing.v_display < 480)
                        return false;
        } else {
                // Test if mode is usable for a chip that is connected to a laptop LCD
                // display or a monitor via a DVI interface.

                // If chip is a Mach64 Mobility chip exclude 640x350 resolution since
                // that resolution can not be set without a failure in the VESA set mode
                // function.

                if (si.chipType == MACH64_MOBILITY && mode->timing.h_display == 640
                                && mode->timing.v_display == 350)
                        return false;

                // Search VESA mode table for matching mode.

                if (GetVesaModeNumber(*mode, bitsPerPixel) == 0)
                        return false;
        }

        return true;
}


status_t
CreateModeList(bool (*checkMode)(const display_mode* mode))
{
        SharedInfo& si = *gInfo.sharedInfo;

        // Obtain EDID info which is needed for for building the mode list.
        // However, if a laptop's LCD display is active, bypass getting the EDID
        // info since it is not needed, and if the external display supports only
        // resolutions smaller than the size of the laptop LCD display, it would
        // unnecessarily restrict size of the resolutions that could be set for
        // laptop LCD display.

        si.bHaveEDID = false;

        if (si.displayType == MT_VGA && !si.bHaveEDID) {
                edid1_raw rawEdid;      // raw EDID info to obtain

                if (ioctl(gInfo.deviceFileDesc, ATI_GET_EDID, &rawEdid,
                                sizeof(rawEdid)) == B_OK) {
                        if (rawEdid.version.version != 1 || rawEdid.version.revision > 4) {
                                TRACE("CreateModeList(); EDID version %d.%d out of range\n",
                                        rawEdid.version.version, rawEdid.version.revision);
                        } else {
                                edid_decode(&si.edidInfo, &rawEdid);    // decode & save EDID info
                                si.bHaveEDID = true;
                        }
                }

                if (si.bHaveEDID) {
#ifdef ENABLE_DEBUG_TRACE
                        edid_dump(&(si.edidInfo));
#endif
                } else {
                        TRACE("CreateModeList(); Unable to get EDID info\n");
                }
        }

        display_mode* list;
        uint32 count = 0;
        area_id listArea;

        listArea = create_display_modes("ATI modes",
                si.bHaveEDID ? &si.edidInfo : NULL,
                NULL, 0, si.colorSpaces, si.colorSpaceCount,
                (check_display_mode_hook)checkMode, &list, &count);

        if (listArea < 0)
                return listArea;                // listArea has error code

        si.modeArea = gInfo.modeListArea = listArea;
        si.modeCount = count;
        gInfo.modeList = list;

        return B_OK;
}



status_t
ProposeDisplayMode(display_mode *target, const display_mode *low,
        const display_mode *high)
{
        (void)low;              // avoid compiler warning for unused arg
        (void)high;             // avoid compiler warning for unused arg

        TRACE("ProposeDisplayMode()  %dx%d, pixel clock: %d kHz, space: 0x%X\n",
                target->timing.h_display, target->timing.v_display,
                target->timing.pixel_clock, target->space);

        // Search the mode list for the specified mode.

        uint32 modeCount = gInfo.sharedInfo->modeCount;

        for (uint32 j = 0; j < modeCount; j++) {
                display_mode& mode = gInfo.modeList[j];

                if (target->timing.h_display == mode.timing.h_display
                        && target->timing.v_display == mode.timing.v_display
                        && target->space == mode.space)
                        return B_OK;    // mode found in list
        }

        return B_BAD_VALUE;             // mode not found in list
}


status_t
SetDisplayMode(display_mode* pMode)
{
        // First validate the mode, then call a function to set the registers.

        TRACE("SetDisplayMode() begin\n");

        SharedInfo& si = *gInfo.sharedInfo;
        DisplayModeEx mode;
        (display_mode&)mode = *pMode;

        uint32 maxPixelClock;
        if ( ! gInfo.GetColorSpaceParams(mode.space, mode.bitsPerPixel, maxPixelClock))
                return B_BAD_VALUE;

        if (ProposeDisplayMode(&mode, pMode, pMode) != B_OK)
                return B_BAD_VALUE;

        int bytesPerPixel = (mode.bitsPerPixel + 7) / 8;
        mode.bytesPerRow = mode.timing.h_display * bytesPerPixel;

        // Is there enough frame buffer memory for this mode?

        if ( ! IsThereEnoughFBMemory(&mode, mode.bitsPerPixel))
                return B_NO_MEMORY;

        TRACE("Set display mode: %dx%d  virtual size: %dx%d  color depth: %d bits/pixel\n",
                mode.timing.h_display, mode.timing.v_display,
                mode.virtual_width, mode.virtual_height, mode.bitsPerPixel);

        if (si.displayType == MT_VGA) {
                TRACE("   mode timing: %d  %d %d %d %d  %d %d %d %d\n",
                        mode.timing.pixel_clock,
                        mode.timing.h_display,
                        mode.timing.h_sync_start, mode.timing.h_sync_end,
                        mode.timing.h_total,
                        mode.timing.v_display,
                        mode.timing.v_sync_start, mode.timing.v_sync_end,
                        mode.timing.v_total);
        
                TRACE("   mode hFreq: %.1f kHz  vFreq: %.1f Hz  %chSync %cvSync\n",
                        double(mode.timing.pixel_clock) / mode.timing.h_total,
                        ((double(mode.timing.pixel_clock) / mode.timing.h_total) * 1000.0)
                        / mode.timing.v_total,
                        (mode.timing.flags & B_POSITIVE_HSYNC) ? '+' : '-',
                        (mode.timing.flags & B_POSITIVE_VSYNC) ? '+' : '-');
        }
        
        status_t status = gInfo.SetDisplayMode(mode);
        if (status != B_OK) {
                TRACE("SetDisplayMode() failed;  status 0x%x\n", status);
                return status;
        }

        si.displayMode = mode;

        TRACE("SetDisplayMode() done\n");
        return B_OK;
}



status_t
MoveDisplay(uint16 horizontalStart, uint16 verticalStart)
{
        // Set which pixel of the virtual frame buffer will show up in the
        // top left corner of the display device.       Used for page-flipping
        // games and virtual desktops.

        DisplayModeEx& mode = gInfo.sharedInfo->displayMode;

        if (mode.timing.h_display + horizontalStart > mode.virtual_width
                || mode.timing.v_display + verticalStart > mode.virtual_height)
                return B_ERROR;

        mode.h_display_start = horizontalStart;
        mode.v_display_start = verticalStart;

        gInfo.AdjustFrame(mode);
        return B_OK;
}


uint32
AccelerantModeCount(void)
{
        // Return the number of display modes in the mode list.

        return gInfo.sharedInfo->modeCount;
}


status_t
GetModeList(display_mode* dmList)
{
        // Copy the list of supported video modes to the location pointed at
        // by dmList.

        memcpy(dmList, gInfo.modeList, gInfo.sharedInfo->modeCount * sizeof(display_mode));
        return B_OK;
}


status_t
GetDisplayMode(display_mode* current_mode)
{
        *current_mode = gInfo.sharedInfo->displayMode;  // return current display mode
        return B_OK;
}


status_t
GetFrameBufferConfig(frame_buffer_config* pFBC)
{
        SharedInfo& si = *gInfo.sharedInfo;

        pFBC->frame_buffer = (void*)((addr_t)si.videoMemAddr + si.frameBufferOffset);
        pFBC->frame_buffer_dma = (void*)((addr_t)si.videoMemPCI + si.frameBufferOffset);
        uint32 bytesPerPixel = (si.displayMode.bitsPerPixel + 7) / 8;
        pFBC->bytes_per_row = si.displayMode.virtual_width * bytesPerPixel;

        return B_OK;
}


status_t
GetPixelClockLimits(display_mode* mode, uint32* low, uint32* high)
{
        // Return the maximum and minium pixel clock limits for the specified mode.

        uint8 bitsPerPixel;
        uint32 maxPixelClock;

        if ( ! gInfo.GetColorSpaceParams(mode->space, bitsPerPixel, maxPixelClock))
                return B_ERROR;

        if (low != NULL) {
                // lower limit of about 48Hz vertical refresh
                uint32 totalClocks = (uint32)mode->timing.h_total * (uint32)mode->timing.v_total;
                uint32 lowClock = (totalClocks * 48L) / 1000L;
                if (lowClock > maxPixelClock)
                        return B_ERROR;

                *low = lowClock;
        }

        if (high != NULL)
                *high = maxPixelClock;

        return B_OK;
}


status_t
GetTimingConstraints(display_timing_constraints *constraints)
{
        (void)constraints;              // avoid compiler warning for unused arg

        return B_ERROR;
}


status_t
GetPreferredDisplayMode(display_mode* preferredMode)
{
        // If the chip is connected to a laptop LCD panel, find the mode with
        // matching width and height, 60 Hz refresh rate, and greatest color depth.

        SharedInfo& si = *gInfo.sharedInfo;

        if (si.displayType == MT_LAPTOP) {
                display_mode* mode = FindDisplayMode(si.panelX, si.panelY, 60, 0);

                if (mode != NULL) {
                        *preferredMode = *mode;
                        return B_OK;
                }
        }

        return B_ERROR;
}


status_t
GetEdidInfo(void* info, size_t size, uint32* _version)
{
        SharedInfo& si = *gInfo.sharedInfo;

        if ( ! si.bHaveEDID)
                return B_ERROR;

        if (size < sizeof(struct edid1_info))
                return B_BUFFER_OVERFLOW;

        memcpy(info, &si.edidInfo, sizeof(struct edid1_info));
        *_version = EDID_VERSION_1;
        return B_OK;
}