/*
 * Context and render target management in wined3d
 *
 * Copyright 2002-2004 Jason Edmeades
 * Copyright 2002-2004 Raphael Junqueira
 * Copyright 2004 Christian Costa
 * Copyright 2005 Oliver Stieber
 * Copyright 2006, 2008 Henri Verbeet
 * Copyright 2007-2011, 2013 Stefan Dösinger for CodeWeavers
 * Copyright 2009-2011 Henri Verbeet for CodeWeavers
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
 */

#include "wined3d_private.h"

WINE_DEFAULT_DEBUG_CHANNEL(d3d);
WINE_DECLARE_DEBUG_CHANNEL(d3d_perf);

void context_resource_released(const struct wined3d_device *device, struct wined3d_resource *resource)
{
    unsigned int i;

    for (i = 0; i < device->context_count; ++i)
    {
        struct wined3d_context *context = device->contexts[i];

        if (&context->current_rt.texture->resource == resource)
        {
            context->current_rt.texture = NULL;
            context->current_rt.sub_resource_idx = 0;
        }
    }
}

void wined3d_context_cleanup(struct wined3d_context *context)
{
}

/* This is used when a context for render target A is active, but a separate context is
 * needed to access the WGL framebuffer for render target B. Re-acquire a context for rt
 * A to avoid breaking caller code. */
void context_restore(struct wined3d_context *context, struct wined3d_texture *texture, unsigned int sub_resource_idx)
{
    if (context->current_rt.texture != texture || context->current_rt.sub_resource_idx != sub_resource_idx)
    {
        context_release(context);
        context = context_acquire(texture->resource.device, texture, sub_resource_idx);
    }

    context_release(context);
}

void context_invalidate_compute_state(struct wined3d_context *context, DWORD state_id)
{
    DWORD representative = context->state_table[state_id].representative - STATE_COMPUTE_OFFSET;
    unsigned int index, shift;

    index = representative / (sizeof(*context->dirty_compute_states) * CHAR_BIT);
    shift = representative & (sizeof(*context->dirty_compute_states) * CHAR_BIT - 1);
    context->dirty_compute_states[index] |= (1u << shift);
}

void context_invalidate_state(struct wined3d_context *context, unsigned int state_id)
{
    unsigned int representative = context->state_table[state_id].representative;
    unsigned int index, shift;

    if (!representative)
        ERR("Invalidating representative 0, state_id %u.\n", state_id);

    index = representative / (sizeof(*context->dirty_graphics_states) * CHAR_BIT);
    shift = representative & ((sizeof(*context->dirty_graphics_states) * CHAR_BIT) - 1);
    context->dirty_graphics_states[index] |= (1u << shift);
}

void wined3d_context_init(struct wined3d_context *context, struct wined3d_swapchain *swapchain)
{
    struct wined3d_device *device = swapchain->device;
    DWORD state;

    context->d3d_info = &device->adapter->d3d_info;
    context->state_table = device->state_table;

    /* Mark all states dirty to force a proper initialization of the states on
     * the first use of the context. Compute states do not need initialization. */
    for (state = 0; state <= STATE_HIGHEST; ++state)
    {
        if (context->state_table[state].representative && !STATE_IS_COMPUTE(state))
            context_invalidate_state(context, state);
    }

    context->device = device;
    context->swapchain = swapchain;
    context->current_rt.texture = swapchain->front_buffer;
    context->current_rt.sub_resource_idx = 0;

    context->shader_update_mask = (1u << WINED3D_SHADER_TYPE_PIXEL)
            | (1u << WINED3D_SHADER_TYPE_VERTEX)
            | (1u << WINED3D_SHADER_TYPE_GEOMETRY)
            | (1u << WINED3D_SHADER_TYPE_HULL)
            | (1u << WINED3D_SHADER_TYPE_DOMAIN)
            | (1u << WINED3D_SHADER_TYPE_COMPUTE);
}

HRESULT wined3d_context_no3d_init(struct wined3d_context *context_no3d, struct wined3d_swapchain *swapchain)
{
    TRACE("context_no3d %p, swapchain %p.\n", context_no3d, swapchain);

    wined3d_context_init(context_no3d, swapchain);

    return WINED3D_OK;
}

static BOOL fixed_get_input(BYTE usage, BYTE usage_idx, unsigned int *regnum)
{
    if ((usage == WINED3D_DECL_USAGE_POSITION || usage == WINED3D_DECL_USAGE_POSITIONT) && !usage_idx)
        *regnum = WINED3D_FFP_POSITION;
    else if (usage == WINED3D_DECL_USAGE_BLEND_WEIGHT && !usage_idx)
        *regnum = WINED3D_FFP_BLENDWEIGHT;
    else if (usage == WINED3D_DECL_USAGE_BLEND_INDICES && !usage_idx)
        *regnum = WINED3D_FFP_BLENDINDICES;
    else if (usage == WINED3D_DECL_USAGE_NORMAL && !usage_idx)
        *regnum = WINED3D_FFP_NORMAL;
    else if (usage == WINED3D_DECL_USAGE_PSIZE && !usage_idx)
        *regnum = WINED3D_FFP_PSIZE;
    else if (usage == WINED3D_DECL_USAGE_COLOR && !usage_idx)
        *regnum = WINED3D_FFP_DIFFUSE;
    else if (usage == WINED3D_DECL_USAGE_COLOR && usage_idx == 1)
        *regnum = WINED3D_FFP_SPECULAR;
    else if (usage == WINED3D_DECL_USAGE_TEXCOORD && usage_idx < WINED3DDP_MAXTEXCOORD)
        *regnum = WINED3D_FFP_TEXCOORD0 + usage_idx;
    else
    {
        WARN("Unsupported input stream [usage=%s, usage_idx=%u].\n", debug_d3ddeclusage(usage), usage_idx);
        *regnum = ~0u;
        return FALSE;
    }

    return TRUE;
}

/* Context activation is done by the caller. */
void wined3d_stream_info_from_declaration(struct wined3d_stream_info *stream_info,
        const struct wined3d_state *state, const struct wined3d_d3d_info *d3d_info)
{
    /* We need to deal with frequency data! */
    struct wined3d_vertex_declaration *declaration = state->vertex_declaration;
    BOOL generic_attributes = d3d_info->ffp_generic_attributes;
    BOOL use_vshader = use_vs(state);
    unsigned int i;

    stream_info->use_map = 0;
    stream_info->swizzle_map = 0;
    stream_info->position_transformed = 0;

    if (!declaration)
        return;

    stream_info->position_transformed = declaration->position_transformed;

    /* Translate the declaration into strided data. */
    for (i = 0; i < declaration->element_count; ++i)
    {
        const struct wined3d_vertex_declaration_element *element = &declaration->elements[i];
        const struct wined3d_stream_state *stream = &state->streams[element->input_slot];
        BOOL stride_used;
        unsigned int idx;

        TRACE("%p Element %p (%u of %u).\n", declaration->elements,
                element, i + 1, declaration->element_count);

        if (!stream->buffer)
            continue;

        TRACE("offset %u input_slot %u usage_idx %d.\n", element->offset, element->input_slot, element->usage_idx);

        if (use_vshader)
        {
            if (element->output_slot == WINED3D_OUTPUT_SLOT_UNUSED)
            {
                stride_used = FALSE;
            }
            else if (element->output_slot == WINED3D_OUTPUT_SLOT_SEMANTIC)
            {
                /* TODO: Assuming vertexdeclarations are usually used with the
                 * same or a similar shader, it might be worth it to store the
                 * last used output slot and try that one first. */
                stride_used = vshader_get_input(state->shader[WINED3D_SHADER_TYPE_VERTEX],
                        element->usage, element->usage_idx, &idx);
            }
            else
            {
                idx = element->output_slot;
                stride_used = TRUE;
            }
        }
        else
        {
            if (!generic_attributes && !element->ffp_valid)
            {
                WARN("Skipping unsupported fixed function element of format %s and usage %s.\n",
                        debug_d3dformat(element->format->id), debug_d3ddeclusage(element->usage));
                stride_used = FALSE;
            }
            else
            {
                stride_used = fixed_get_input(element->usage, element->usage_idx, &idx);
            }
        }

        if (stride_used)
        {
            TRACE("Load %s array %u [usage %s, usage_idx %u, "
                    "input_slot %u, offset %u, stride %u, format %s, class %s, step_rate %u].\n",
                    use_vshader ? "shader": "fixed function", idx,
                    debug_d3ddeclusage(element->usage), element->usage_idx, element->input_slot,
                    element->offset, stream->stride, debug_d3dformat(element->format->id),
                    debug_d3dinput_classification(element->input_slot_class), element->instance_data_step_rate);

            stream_info->elements[idx].format = element->format;
            stream_info->elements[idx].data.buffer_object = 0;
            stream_info->elements[idx].data.addr = (BYTE *)NULL + stream->offset + element->offset;
            stream_info->elements[idx].stride = stream->stride;
            stream_info->elements[idx].stream_idx = element->input_slot;
            if (stream->flags & WINED3DSTREAMSOURCE_INSTANCEDATA)
            {
                stream_info->elements[idx].divisor = 1;
                stream_info->elements[idx].instanced = true;
            }
            else if (element->input_slot_class == WINED3D_INPUT_PER_INSTANCE_DATA)
            {
                stream_info->elements[idx].divisor = element->instance_data_step_rate;
                stream_info->elements[idx].instanced = true;
            }
            else
            {
                stream_info->elements[idx].divisor = 0;
                stream_info->elements[idx].instanced = false;
            }

            if (!d3d_info->vertex_bgra && element->format->id == WINED3DFMT_B8G8R8A8_UNORM)
            {
                stream_info->swizzle_map |= 1u << idx;
            }
            stream_info->use_map |= 1u << idx;
        }
    }
}

/* Context activation is done by the caller. */
void context_update_stream_info(struct wined3d_context *context, const struct wined3d_state *state)
{
    struct wined3d_stream_info *stream_info = &context->stream_info;
    const struct wined3d_d3d_info *d3d_info = context->d3d_info;
    DWORD prev_all_vbo = stream_info->all_vbo;
    unsigned int i;
    uint32_t map;

    wined3d_stream_info_from_declaration(stream_info, state, d3d_info);

    stream_info->all_vbo = 1;
    map = stream_info->use_map;
    while (map)
    {
        struct wined3d_stream_info_element *element;
        struct wined3d_bo_address data;
        struct wined3d_buffer *buffer;

        i = wined3d_bit_scan(&map);
        element = &stream_info->elements[i];
        buffer = state->streams[element->stream_idx].buffer;

        /* We can't use VBOs if the base vertex index is negative. OpenGL
         * doesn't accept negative offsets (or rather offsets bigger than the
         * VBO, because the pointer is unsigned), so use system memory
         * sources. In most sane cases the pointer - offset will still be > 0,
         * otherwise it will wrap around to some big value. Hope that with the
         * indices the driver wraps it back internally. If not,
         * draw_primitive_immediate_mode() is needed, including a vertex buffer
         * path. */
        if (state->load_base_vertex_index < 0)
        {
            WARN_(d3d_perf)("load_base_vertex_index is < 0 (%d), not using VBOs.\n",
                    state->load_base_vertex_index);
            element->data.buffer_object = 0;
            element->data.addr += (ULONG_PTR)wined3d_buffer_load_sysmem(buffer, context);
            if ((UINT_PTR)element->data.addr < -state->load_base_vertex_index * element->stride)
                FIXME("System memory vertex data load offset is negative!\n");
        }
        else
        {
            wined3d_buffer_load(buffer, context, state);
            wined3d_buffer_get_memory(buffer, context, &data);
            element->data.buffer_object = data.buffer_object;
            element->data.addr += (ULONG_PTR)data.addr;
        }

        if (!element->data.buffer_object)
            stream_info->all_vbo = 0;

        TRACE("Load array %u %s.\n", i, debug_bo_address(&element->data));
    }

    if (prev_all_vbo != stream_info->all_vbo)
        context_invalidate_state(context, STATE_INDEXBUFFER);

    context->use_immediate_mode_draw = FALSE;

    if (stream_info->all_vbo)
        return;

    if (!use_vs(state))
    {
        WORD slow_mask = -!d3d_info->ffp_generic_attributes & (1u << WINED3D_FFP_PSIZE);
        slow_mask |= -(!d3d_info->vertex_bgra && !d3d_info->ffp_generic_attributes)
                & ((1u << WINED3D_FFP_DIFFUSE) | (1u << WINED3D_FFP_SPECULAR) | (1u << WINED3D_FFP_BLENDWEIGHT));

        if ((stream_info->position_transformed && !d3d_info->xyzrhw)
                || (stream_info->use_map & slow_mask))
            context->use_immediate_mode_draw = TRUE;
    }
}

static bool is_resource_rtv_bound(const struct wined3d_state *state,
        const struct wined3d_resource *resource)
{
    unsigned int i;

    if (!resource->rtv_bind_count_device)
        return false;

    for (i = 0; i < ARRAY_SIZE(state->fb.render_targets); ++i)
    {
        if (state->fb.render_targets[i] && state->fb.render_targets[i]->resource == resource)
            return true;
    }

    return false;
}

/* Context activation is done by the caller. */
static void context_preload_texture(struct wined3d_context *context,
        const struct wined3d_state *state, unsigned int idx)
{
    struct wined3d_texture *texture;

    if (!(texture = state->textures[idx]))
        return;

    if (is_resource_rtv_bound(state, &texture->resource)
            || (state->fb.depth_stencil && state->fb.depth_stencil->resource == &texture->resource))
        context->uses_fbo_attached_resources = 1;

    wined3d_texture_load(texture, context, is_srgb_enabled(state->sampler_states[idx]));
}

/* Context activation is done by the caller. */
void context_preload_textures(struct wined3d_context *context, const struct wined3d_state *state)
{
    unsigned int i;

    if (use_vs(state))
    {
        for (i = 0; i < WINED3D_MAX_VERTEX_SAMPLERS; ++i)
        {
            if (state->shader[WINED3D_SHADER_TYPE_VERTEX]->reg_maps.resource_info[i].type)
                context_preload_texture(context, state, WINED3D_MAX_FRAGMENT_SAMPLERS + i);
        }
    }

    if (use_ps(state))
    {
        for (i = 0; i < WINED3D_MAX_FRAGMENT_SAMPLERS; ++i)
        {
            if (state->shader[WINED3D_SHADER_TYPE_PIXEL]->reg_maps.resource_info[i].type)
                context_preload_texture(context, state, i);
        }
    }
    else
    {
        uint32_t ffu_map = context->fixed_function_usage_map;

        while (ffu_map)
        {
            i = wined3d_bit_scan(&ffu_map);
            context_preload_texture(context, state, i);
        }
    }
}