/*
 * $Id: $
 *
 * Copyright © 2006 Keith Packard
 *
 * Permission to use, copy, modify, distribute, and sell this software and its
 * documentation for any purpose is hereby granted without fee, provided that
 * the above copyright notice appear in all copies and that both that
 * copyright notice and this permission notice appear in supporting
 * documentation, and that the name of Keith Packard not be used in
 * advertising or publicity pertaining to distribution of the software without
 * specific, written prior permission.  Keith Packard makes no
 * representations about the suitability of this software for any purpose.  It
 * is provided "as is" without express or implied warranty.
 *
 * KEITH PACKARD DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
 * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
 * EVENT SHALL KEITH PACKARD BE LIABLE FOR ANY SPECIAL, INDIRECT OR
 * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
 * DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
 * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
 * PERFORMANCE OF THIS SOFTWARE.
 */

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#include <stddef.h>
#include <string.h>
#include <stdio.h>

#include "xf86.h"
#include "xf86DDC.h"
#include "i830.h"
#include "i830_xf86Crtc.h"
#include "X11/extensions/render.h"

/*
 * Crtc functions
 */
xf86CrtcPtr
xf86CrtcCreate (ScrnInfoPtr		scrn,
		const xf86CrtcFuncsRec	*funcs)
{
    xf86CrtcConfigPtr   xf86_config = XF86_CRTC_CONFIG_PTR(scrn);
    xf86CrtcPtr		crtc;

    crtc = xcalloc (sizeof (xf86CrtcRec), 1);
    if (!crtc)
	return NULL;
    crtc->scrn = scrn;
    crtc->funcs = funcs;
#ifdef RANDR_12_INTERFACE
    crtc->randr_crtc = NULL;
#endif
    xf86_config->crtc[xf86_config->num_crtc++] = crtc;
    return crtc;
}

void
xf86CrtcDestroy (xf86CrtcPtr crtc)
{
    xf86CrtcConfigPtr   xf86_config = XF86_CRTC_CONFIG_PTR(crtc->scrn);
    int			c;
    
    (*crtc->funcs->destroy) (crtc);
    for (c = 0; c < xf86_config->num_crtc; c++)
	if (xf86_config->crtc[c] == crtc)
	{
	    memmove (&xf86_config->crtc[c],
		     &xf86_config->crtc[c+1],
		     xf86_config->num_crtc - (c + 1));
	    xf86_config->num_crtc--;
	    break;
	}
    xfree (crtc);
}

/*
 * Output functions
 */
xf86OutputPtr
xf86OutputCreate (ScrnInfoPtr		    scrn,
		  const xf86OutputFuncsRec *funcs,
		  const char		    *name)
{
    xf86OutputPtr	output;
    xf86CrtcConfigPtr   xf86_config = XF86_CRTC_CONFIG_PTR(scrn);
    int			len = strlen (name);

    output = xcalloc (sizeof (xf86OutputRec) + len + 1, 1);
    if (!output)
	return NULL;
    output->scrn = scrn;
    output->funcs = funcs;
    output->name = (char *) (output + 1);
    output->subpixel_order = SubPixelUnknown;
    strcpy (output->name, name);
#ifdef RANDR_12_INTERFACE
    output->randr_output = NULL;
#endif
    xf86_config->output[xf86_config->num_output++] = output;
    return output;
}

void
xf86OutputDestroy (xf86OutputPtr output)
{
    ScrnInfoPtr		scrn = output->scrn;
    xf86CrtcConfigPtr   xf86_config = XF86_CRTC_CONFIG_PTR(scrn);
    int			o;
    
    (*output->funcs->destroy) (output);
    while (output->probed_modes)
	xf86DeleteMode (&output->probed_modes, output->probed_modes);
    for (o = 0; o < xf86_config->num_output; o++)
	if (xf86_config->output[o] == output)
	{
	    memmove (&xf86_config->output[o],
		     &xf86_config->output[o+1],
		     xf86_config->num_output - (o + 1));
	    xf86_config->num_output--;
	    break;
	}
    xfree (output);
}

static DisplayModePtr
xf86DefaultMode (xf86OutputPtr output)
{
    DisplayModePtr  target_mode = NULL;
    DisplayModePtr  mode;
    int		    target_diff = 0;
    int		    target_preferred = 0;
    int		    mm_height;
    
    mm_height = output->mm_height;
    if (!mm_height)
	mm_height = 203;	/* 768 pixels at 96dpi */
    /*
     * Pick a mode closest to 96dpi 
     */
    for (mode = output->probed_modes; mode; mode = mode->next)
    {
	int	    dpi;
	int	    preferred = (mode->type & M_T_PREFERRED) != 0;
	int	    diff;

	dpi = (mode->HDisplay * 254) / (mm_height * 10);
	diff = dpi - 96;
	diff = diff < 0 ? -diff : diff;
	if (target_mode == NULL || (preferred > target_preferred) ||
	    (preferred == target_preferred && diff < target_diff))
	{
	    target_mode = mode;
	    target_diff = diff;
	    target_preferred = preferred;
	}
    }
    return target_mode;
}

static DisplayModePtr
xf86ClosestMode (xf86OutputPtr output, DisplayModePtr match)
{
    DisplayModePtr  target_mode = NULL;
    DisplayModePtr  mode;
    int		    target_diff = 0;
    
    /*
     * Pick a mode closest to the specified mode
     */
    for (mode = output->probed_modes; mode; mode = mode->next)
    {
	int	    dx, dy;
	int	    diff;

	/* exact matches are preferred */
	if (xf86ModesEqual (mode, match))
	    return mode;
	
	dx = match->HDisplay - mode->HDisplay;
	dy = match->VDisplay - mode->VDisplay;
	diff = dx * dx + dy * dy;
	if (target_mode == NULL || diff < target_diff)
	{
	    target_mode = mode;
	    target_diff = diff;
	}
    }
    return target_mode;
}

static Bool
xf86OutputHasPreferredMode (xf86OutputPtr output)
{
    DisplayModePtr  mode;

    for (mode = output->probed_modes; mode; mode = mode->next)
	if (mode->type & M_T_PREFERRED)
	    return TRUE;
    return FALSE;
}

static int
xf86PickCrtcs (ScrnInfoPtr	pScrn,
	       xf86CrtcPtr	*best_crtcs,
	       DisplayModePtr	*modes,
	       int		n)
{
    xf86CrtcConfigPtr	config = XF86_CRTC_CONFIG_PTR(pScrn);
    int		    c, o, l;
    xf86OutputPtr   output;
    xf86CrtcPtr	    crtc;
    xf86CrtcPtr	    *crtcs;
    xf86CrtcPtr	    best_crtc;
    int		    best_score;
    int		    score;
    int		    my_score;
    
    if (n == config->num_output)
	return 0;
    output = config->output[n];
    
    /*
     * Compute score with this output disabled
     */
    best_crtcs[n] = NULL;
    best_crtc = NULL;
    best_score = xf86PickCrtcs (pScrn, best_crtcs, modes, n+1);
    if (modes[n] == NULL)
	return best_score;
    
    crtcs = xalloc (config->num_output * sizeof (xf86CrtcPtr));
    if (!crtcs)
	return best_score;

    my_score = 1;
    /* Score outputs that are known to be connected higher */
    if (output->status == XF86OutputStatusConnected)
	my_score++;
    /* Score outputs with preferred modes higher */
    if (xf86OutputHasPreferredMode (output))
	my_score++;
    /*
     * Select a crtc for this output and
     * then attempt to configure the remaining
     * outputs
     */
    for (c = 0; c < config->num_crtc; c++)
    {
	if ((output->possible_crtcs & (1 << c)) == 0)
	    continue;
	
	crtc = config->crtc[c];
	/*
	 * Check to see if some other output is
	 * using this crtc
	 */
	for (o = 0; o < n; o++)
	    if (best_crtcs[o] == crtc)
		break;
	if (o < n)
	{
	    /*
	     * If the two outputs desire the same mode,
	     * see if they can be cloned
	     */
	    if (xf86ModesEqual (modes[o], modes[n]))
	    {
		for (l = 0; l < config->num_output; l++)
		    if (output->possible_clones & (1 << l))
			break;
		if (l == config->num_output)
		    continue;		/* nope, try next CRTC */
	    }
	    else
		continue;		/* different modes, can't clone */
	}
	crtcs[n] = crtc;
	memcpy (crtcs, best_crtcs, n * sizeof (xf86CrtcPtr));
	score = my_score + xf86PickCrtcs (pScrn, crtcs, modes, n+1);
	if (score >= best_score)
	{
	    best_crtc = crtc;
	    best_score = score;
	    memcpy (best_crtcs, crtcs, config->num_output * sizeof (xf86CrtcPtr));
	}
    }
    xfree (crtcs);
    return best_score;
}


/*
 * Compute the virtual size necessary to place all of the available
 * crtcs in a panorama configuration
 */

static void
xf86DefaultScreenLimits (ScrnInfoPtr pScrn, int *widthp, int *heightp)
{
    xf86CrtcConfigPtr	config = XF86_CRTC_CONFIG_PTR(pScrn);
    int	    width = 0, height = 0;
    int	    o;
    int	    c;
    int	    s;

    for (c = 0; c < config->num_crtc; c++)
    {
	int	    crtc_width = 1600, crtc_height = 1200;

	for (o = 0; o < config->num_output; o++) 
	{
	    xf86OutputPtr   output = config->output[o];

	    for (s = 0; s < config->num_crtc; s++)
		if (output->possible_crtcs & (1 << s))
		{
		    DisplayModePtr  mode;
		    for (mode = output->probed_modes; mode; mode = mode->next)
		    {
			if (mode->HDisplay > crtc_width)
			    crtc_width = mode->HDisplay;
			if (mode->VDisplay > crtc_width)
			    crtc_height = mode->VDisplay;
		    }
		}
	}
	if (crtc_width > width)
	    width = crtc_width;
	if (crtc_height > height)
	    height = crtc_height;
    }
    *widthp = width;
    *heightp = height;
}

void
xf86ProbeOutputModes (ScrnInfoPtr pScrn)
{
    xf86CrtcConfigPtr	config = XF86_CRTC_CONFIG_PTR(pScrn);
    Bool		properties_set = FALSE;
    int			o;

    /* Probe the list of modes for each output. */
    for (o = 0; o < config->num_output; o++) 
    {
	xf86OutputPtr  output = config->output[o];
	DisplayModePtr mode;

	while (output->probed_modes != NULL)
	    xf86DeleteMode(&output->probed_modes, output->probed_modes);

	output->probed_modes = (*output->funcs->get_modes) (output);

	/* Set the DDC properties to whatever first output has DDC information.
	 */
	if (output->MonInfo != NULL && !properties_set) {
	    xf86SetDDCproperties(pScrn, output->MonInfo);
	    properties_set = TRUE;
	}

#ifdef DEBUG_REPROBE
	if (output->probed_modes != NULL) {
	    xf86DrvMsg(pScrn->scrnIndex, X_INFO,
		       "Printing probed modes for output %s\n",
		       output->name);
	} else {
	    xf86DrvMsg(pScrn->scrnIndex, X_INFO,
		       "No remaining probed modes for output %s\n",
		       output->name);
	}
#endif
	for (mode = output->probed_modes; mode != NULL; mode = mode->next)
	{
	    /* The code to choose the best mode per pipe later on will require
	     * VRefresh to be set.
	     */
	    mode->VRefresh = xf86ModeVRefresh(mode);
	    xf86SetModeCrtc(mode, INTERLACE_HALVE_V);

#ifdef DEBUG_REPROBE
	    xf86PrintModeline(pScrn->scrnIndex, mode);
#endif
	}
    }
}


/**
 * Copy one of the output mode lists to the ScrnInfo record
 */

/* XXX where does this function belong? Here? */
void
xf86RandR12GetOriginalVirtualSize(ScrnInfoPtr pScrn, int *x, int *y);

void
xf86SetScrnInfoModes (ScrnInfoPtr pScrn)
{
    xf86CrtcConfigPtr	config = XF86_CRTC_CONFIG_PTR(pScrn);
    xf86OutputPtr	output;
    xf86CrtcPtr		crtc;
    DisplayModePtr	last, mode;
    int			originalVirtualX, originalVirtualY;

    output = config->output[config->compat_output];
    if (!output->crtc)
    {
	int o;

	output = NULL;
	for (o = 0; o < config->num_output; o++)
	    if (config->output[o]->crtc)
	    {
		config->compat_output = o;
		output = config->output[o];
		break;
	    }
	/* no outputs are active, punt and leave things as they are */
	if (!output)
	    return;
    }
    crtc = output->crtc;

    /* Clear any existing modes from pScrn->modes */
    while (pScrn->modes != NULL)
	xf86DeleteMode(&pScrn->modes, pScrn->modes);

    /* Set pScrn->modes to the mode list for the 'compat' output */
    pScrn->modes = xf86DuplicateModes(pScrn, output->probed_modes);

    xf86RandR12GetOriginalVirtualSize(pScrn, &originalVirtualX, &originalVirtualY);

    /* Disable modes in the XFree86 DDX list that are larger than the current
     * virtual size.
     */
    i830xf86ValidateModesSize(pScrn, pScrn->modes,
			      originalVirtualX, originalVirtualY,
			      pScrn->displayWidth);

    /* Strip out anything that we threw out for virtualX/Y. */
    i830xf86PruneInvalidModes(pScrn, &pScrn->modes, TRUE);

    for (mode = pScrn->modes; mode; mode = mode->next)
	if (xf86ModesEqual (mode, &crtc->desiredMode))
	    break;
    
    /* For some reason, pScrn->modes is circular, unlike the other mode lists.
     * How great is that?
     */
    for (last = pScrn->modes; last && last->next; last = last->next);
    last->next = pScrn->modes;
    pScrn->modes->prev = last;
    if (mode)
	while (pScrn->modes != mode)
	    pScrn->modes = pScrn->modes->next;
    pScrn->currentMode = pScrn->modes;
}

/**
 * Construct default screen configuration
 *
 * Given auto-detected (and, eventually, configured) values,
 * construct a usable configuration for the system
 */

Bool
xf86InitialConfiguration (ScrnInfoPtr	    pScrn)
{
    xf86CrtcConfigPtr	config = XF86_CRTC_CONFIG_PTR(pScrn);
    int			o, c;
    DisplayModePtr	target_mode = NULL;
    xf86CrtcPtr		*crtcs;
    DisplayModePtr	*modes;
    int			width, height;

    xf86ProbeOutputModes (pScrn);

    crtcs = xnfcalloc (config->num_output, sizeof (xf86CrtcPtr));
    modes = xnfcalloc (config->num_output, sizeof (DisplayModePtr));
    
    for (o = 0; o < config->num_output; o++)
	modes[o] = NULL;
    
    /*
     * Let outputs with preferred modes drive screen size
     */
    for (o = 0; o < config->num_output; o++)
    {
	xf86OutputPtr output = config->output[o];

	if (output->status != XF86OutputStatusDisconnected &&
	    xf86OutputHasPreferredMode (output))
	{
	    target_mode = xf86DefaultMode (output);
	    if (target_mode)
	    {
		modes[o] = target_mode;
		config->compat_output = o;
		break;
	    }
	}
    }
    if (!target_mode)
    {
	for (o = 0; o < config->num_output; o++)
	{
	    xf86OutputPtr output = config->output[o];
	    if (output->status != XF86OutputStatusDisconnected)
	    {
		target_mode = xf86DefaultMode (output);
		if (target_mode)
		{
		    modes[o] = target_mode;
		    config->compat_output = o;
		    break;
		}
	    }
	}
    }
    for (o = 0; o < config->num_output; o++)
    {
	xf86OutputPtr output = config->output[o];
	
	if (output->status != XF86OutputStatusDisconnected && !modes[o])
	    modes[o] = xf86ClosestMode (output, target_mode);
    }

    if (!xf86PickCrtcs (pScrn, crtcs, modes, 0))
    {
	xfree (crtcs);
	xfree (modes);
	return FALSE;
    }
    
    xf86DefaultScreenLimits (pScrn, &width, &height);
    
    /*
     * Expand virtual size to cover potential mode switches
     */
    if (width > pScrn->virtualX)
	pScrn->virtualX = width;
    if (width > pScrn->display->virtualX)
	pScrn->display->virtualX = width;
    if (height > pScrn->virtualY)
	pScrn->virtualY = height;
    if (height > pScrn->display->virtualY)
	pScrn->display->virtualY = height;
    
    /* XXX override xf86 common frame computation code */
    
    pScrn->display->frameX0 = 0;
    pScrn->display->frameY0 = 0;
    
    for (c = 0; c < config->num_crtc; c++)
    {
	xf86CrtcPtr	crtc = config->crtc[c];

	crtc->enabled = FALSE;
	memset (&crtc->desiredMode, '\0', sizeof (crtc->desiredMode));
    }
	
    /*
     * Set initial configuration
     */
    for (o = 0; o < config->num_output; o++)
    {
	xf86OutputPtr	output = config->output[o];
	DisplayModePtr	mode = modes[o];
        xf86CrtcPtr	crtc = crtcs[o];

	if (mode && crtc)
	{
	    crtc->desiredMode = *mode;
	    crtc->enabled = TRUE;
	    crtc->x = 0;
	    crtc->y = 0;
	    output->crtc = crtc;
	    /* XXX set position; for now, we clone */
	}
    }
    
    /* Mirror output modes to pScrn mode list */
    xf86SetScrnInfoModes (pScrn);
    
    xfree (crtcs);
    xfree (modes);
    return TRUE;
}

/**
 * Set the DPMS power mode of all outputs and CRTCs.
 *
 * If the new mode is off, it will turn off outputs and then CRTCs.
 * Otherwise, it will affect CRTCs before outputs.
 */
void
xf86DPMSSet(ScrnInfoPtr pScrn, int mode, int flags)
{
    xf86CrtcConfigPtr	config = XF86_CRTC_CONFIG_PTR(pScrn);
    int			i;

    if (mode == DPMSModeOff) {
	for (i = 0; i < config->num_output; i++) {
	    xf86OutputPtr output = config->output[i];
	    if (output->crtc != NULL)
		(*output->funcs->dpms) (output, mode);
	}
    }

    for (i = 0; i < config->num_crtc; i++) {
	xf86CrtcPtr crtc = config->crtc[i];
	if (crtc->enabled)
	    (*crtc->funcs->dpms) (crtc, mode);
    }

    if (mode != DPMSModeOff) {
	for (i = 0; i < config->num_output; i++) {
	    xf86OutputPtr output = config->output[i];
	    if (output->crtc != NULL)
		(*output->funcs->dpms) (output, mode);
	}
    }
}