//
// Copyright(C) 1993-1996 Id Software, Inc.
// Copyright(C) 1993-2008 Raven Software
// Copyright(C) 2005-2014 Simon Howard
//
// This program is free software; you can redistribute it and/or
// modify it under the terms of the GNU General Public License
// as published by the Free Software Foundation; either version 2
// of the License, or (at your option) any later version.
//
// This program 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 General Public License for more details.
//
// DESCRIPTION:
//	Gamma correction LUT stuff.
//	Functions to draw patches (by post) directly to screen.
//	Functions to blit a block to the screen.
//

#include "v_video.h"

#include "config.h"
#include "deh_str.h"
#include "doomtype.h"
#include "i_swap.h"
#include "i_system.h"
#include "i_video.h"
#include "m_bbox.h"
#include "m_misc.h"
#include "w_wad.h"
#include "z_zone.h"

#include <math.h>
#include <stdio.h>
#include <string.h>
#ifdef HAVE_LIBPNG
#include <png.h>
#endif

// TODO: There are separate RANGECHECK defines for different games, but this
// is common code. Fix this.
#define RANGECHECK

// Blending table used for fuzzpatch, etc.
// Only used in Heretic/Hexen

byte* tinttable = NULL;

// villsa [STRIFE] Blending table used for Strife
byte* xlatab = NULL;

// The screen buffer that the v_video.c code draws to.

static byte* dest_screen = NULL;

int dirtybox[4];

// haleyjd 08/28/10: clipping callback function for patches.
// This is needed for Chocolate Strife, which clips patches to the screen.
static vpatchclipfunc_t patchclip_callback = NULL;

//
// V_MarkRect
//
void V_MarkRect(int x, int y, int width, int height) {
    // If we are temporarily using an alternate screen, do not
    // affect the update box.

    if (dest_screen == I_VideoBuffer) {
        M_AddToBox(dirtybox, x, y);
        M_AddToBox(dirtybox, x + width - 1, y + height - 1);
    }
}

//
// V_CopyRect
//
void V_CopyRect(int srcx, int srcy, byte* source, int width, int height, int destx, int desty) {
    byte* src;
    byte* dest;

#ifdef RANGECHECK
    if (srcx < 0 || srcx + width > SCREENWIDTH || srcy < 0 || srcy + height > SCREENHEIGHT
        || destx < 0 || destx + width > SCREENWIDTH || desty < 0 || desty + height > SCREENHEIGHT) {
        I_Error("Bad V_CopyRect");
    }
#endif

    V_MarkRect(destx, desty, width, height);

    src = source + SCREENWIDTH * srcy + srcx;
    dest = dest_screen + SCREENWIDTH * desty + destx;

    for (; height > 0; height--) {
        memcpy(dest, src, width);
        src += SCREENWIDTH;
        dest += SCREENWIDTH;
    }
}

//
// V_SetPatchClipCallback
//
// haleyjd 08/28/10: Added for Strife support.
// By calling this function, you can setup runtime error checking for patch
// clipping. Strife never caused errors by drawing patches partway off-screen.
// Some versions of vanilla DOOM also behaved differently than the default
// implementation, so this could possibly be extended to those as well for
// accurate emulation.
//
void V_SetPatchClipCallback(vpatchclipfunc_t func) {
    patchclip_callback = func;
}

//
// V_DrawPatch
// Masks a column based masked pic to the screen.
//

void V_DrawPatch(int x, int y, patch_t* patch) {
    int count;
    int col;
    column_t* column;
    byte* desttop;
    byte* dest;
    byte* source;
    int w;

    y -= SHORT(patch->topoffset);
    x -= SHORT(patch->leftoffset);

    // haleyjd 08/28/10: Strife needs silent error checking here.
    if (patchclip_callback) {
        if (!patchclip_callback(patch, x, y))
            return;
    }

#ifdef RANGECHECK
    if (x < 0 || x + SHORT(patch->width) > SCREENWIDTH || y < 0 || y + SHORT(patch->height) > SCREENHEIGHT) {
        I_Error(
            "Bad V_DrawPatch x=%i y=%i patch.width=%i patch.height=%i topoffset=%i leftoffset=%i",
            x, y, patch->width, patch->height, patch->topoffset, patch->leftoffset);
    }
#endif

    V_MarkRect(x, y, SHORT(patch->width), SHORT(patch->height));

    col = 0;
    desttop = dest_screen + y * SCREENWIDTH + x;

    w = SHORT(patch->width);

    for (; col < w; x++, col++, desttop++) {
        column = (column_t*) ((byte*) patch + LONG(patch->columnofs[col]));

        // step through the posts in a column
        while (column->topdelta != 0xff) {
            source = (byte*) column + 3;
            dest = desttop + column->topdelta * SCREENWIDTH;
            count = column->length;

            while (count--) {
                *dest = *source++;
                dest += SCREENWIDTH;
            }
            column = (column_t*) ((byte*) column + column->length + 4);
        }
    }
}

//
// V_DrawPatchFlipped
// Masks a column based masked pic to the screen.
// Flips horizontally, e.g. to mirror face.
//

void V_DrawPatchFlipped(int x, int y, patch_t* patch) {
    int count;
    int col;
    column_t* column;
    byte* desttop;
    byte* dest;
    byte* source;
    int w;

    y -= SHORT(patch->topoffset);
    x -= SHORT(patch->leftoffset);

    // haleyjd 08/28/10: Strife needs silent error checking here.
    if (patchclip_callback) {
        if (!patchclip_callback(patch, x, y))
            return;
    }

#ifdef RANGECHECK
    if (x < 0 || x + SHORT(patch->width) > SCREENWIDTH || y < 0 || y + SHORT(patch->height) > SCREENHEIGHT) {
        I_Error("Bad V_DrawPatchFlipped");
    }
#endif

    V_MarkRect(x, y, SHORT(patch->width), SHORT(patch->height));

    col = 0;
    desttop = dest_screen + y * SCREENWIDTH + x;

    w = SHORT(patch->width);

    for (; col < w; x++, col++, desttop++) {
        column = (column_t*) ((byte*) patch + LONG(patch->columnofs[w - 1 - col]));

        // step through the posts in a column
        while (column->topdelta != 0xff) {
            source = (byte*) column + 3;
            dest = desttop + column->topdelta * SCREENWIDTH;
            count = column->length;

            while (count--) {
                *dest = *source++;
                dest += SCREENWIDTH;
            }
            column = (column_t*) ((byte*) column + column->length + 4);
        }
    }
}

//
// V_DrawPatchDirect
// Draws directly to the screen on the pc.
//

void V_DrawPatchDirect(int x, int y, patch_t* patch) {
    V_DrawPatch(x, y, patch);
}

//
// V_DrawTLPatch
//
// Masks a column based translucent masked pic to the screen.
//

void V_DrawTLPatch(int x, int y, patch_t* patch) {
    int count, col;
    column_t* column;
    byte *desttop, *dest, *source;
    int w;

    y -= SHORT(patch->topoffset);
    x -= SHORT(patch->leftoffset);

    if (x < 0 || x + SHORT(patch->width) > SCREENWIDTH || y < 0 || y + SHORT(patch->height) > SCREENHEIGHT) {
        I_Error("Bad V_DrawTLPatch");
    }

    col = 0;
    desttop = dest_screen + y * SCREENWIDTH + x;

    w = SHORT(patch->width);
    for (; col < w; x++, col++, desttop++) {
        column = (column_t*) ((byte*) patch + LONG(patch->columnofs[col]));

        // step through the posts in a column

        while (column->topdelta != 0xff) {
            source = (byte*) column + 3;
            dest = desttop + column->topdelta * SCREENWIDTH;
            count = column->length;

            while (count--) {
                *dest = tinttable[((*dest) << 8) + *source++];
                dest += SCREENWIDTH;
            }
            column = (column_t*) ((byte*) column + column->length + 4);
        }
    }
}

//
// V_DrawXlaPatch
//
// villsa [STRIFE] Masks a column based translucent masked pic to the screen.
//

void V_DrawXlaPatch(int x, int y, patch_t* patch) {
    int count, col;
    column_t* column;
    byte *desttop, *dest, *source;
    int w;

    y -= SHORT(patch->topoffset);
    x -= SHORT(patch->leftoffset);

    if (patchclip_callback) {
        if (!patchclip_callback(patch, x, y))
            return;
    }

    col = 0;
    desttop = dest_screen + y * SCREENWIDTH + x;

    w = SHORT(patch->width);
    for (; col < w; x++, col++, desttop++) {
        column = (column_t*) ((byte*) patch + LONG(patch->columnofs[col]));

        // step through the posts in a column

        while (column->topdelta != 0xff) {
            source = (byte*) column + 3;
            dest = desttop + column->topdelta * SCREENWIDTH;
            count = column->length;

            while (count--) {
                *dest = xlatab[*dest + ((*source) << 8)];
                source++;
                dest += SCREENWIDTH;
            }
            column = (column_t*) ((byte*) column + column->length + 4);
        }
    }
}

//
// V_DrawAltTLPatch
//
// Masks a column based translucent masked pic to the screen.
//

void V_DrawAltTLPatch(int x, int y, patch_t* patch) {
    int count, col;
    column_t* column;
    byte *desttop, *dest, *source;
    int w;

    y -= SHORT(patch->topoffset);
    x -= SHORT(patch->leftoffset);

    if (x < 0 || x + SHORT(patch->width) > SCREENWIDTH || y < 0 || y + SHORT(patch->height) > SCREENHEIGHT) {
        I_Error("Bad V_DrawAltTLPatch");
    }

    col = 0;
    desttop = dest_screen + y * SCREENWIDTH + x;

    w = SHORT(patch->width);
    for (; col < w; x++, col++, desttop++) {
        column = (column_t*) ((byte*) patch + LONG(patch->columnofs[col]));

        // step through the posts in a column

        while (column->topdelta != 0xff) {
            source = (byte*) column + 3;
            dest = desttop + column->topdelta * SCREENWIDTH;
            count = column->length;

            while (count--) {
                *dest = tinttable[((*dest) << 8) + *source++];
                dest += SCREENWIDTH;
            }
            column = (column_t*) ((byte*) column + column->length + 4);
        }
    }
}

//
// V_DrawShadowedPatch
//
// Masks a column based masked pic to the screen.
//

void V_DrawShadowedPatch(int x, int y, patch_t* patch) {
    int count, col;
    column_t* column;
    byte *desttop, *dest, *source;
    byte *desttop2, *dest2;
    int w;

    y -= SHORT(patch->topoffset);
    x -= SHORT(patch->leftoffset);

    if (x < 0 || x + SHORT(patch->width) > SCREENWIDTH || y < 0 || y + SHORT(patch->height) > SCREENHEIGHT) {
        I_Error("Bad V_DrawShadowedPatch");
    }

    col = 0;
    desttop = dest_screen + y * SCREENWIDTH + x;
    desttop2 = dest_screen + (y + 2) * SCREENWIDTH + x + 2;

    w = SHORT(patch->width);
    for (; col < w; x++, col++, desttop++, desttop2++) {
        column = (column_t*) ((byte*) patch + LONG(patch->columnofs[col]));

        // step through the posts in a column

        while (column->topdelta != 0xff) {
            source = (byte*) column + 3;
            dest = desttop + column->topdelta * SCREENWIDTH;
            dest2 = desttop2 + column->topdelta * SCREENWIDTH;
            count = column->length;

            while (count--) {
                *dest2 = tinttable[((*dest2) << 8)];
                dest2 += SCREENWIDTH;
                *dest = *source++;
                dest += SCREENWIDTH;
            }
            column = (column_t*) ((byte*) column + column->length + 4);
        }
    }
}

//
// Load tint table from TINTTAB lump.
//

void V_LoadTintTable(void) {
    tinttable = W_CacheLumpName("TINTTAB", PU_STATIC);
}

//
// V_LoadXlaTable
//
// villsa [STRIFE] Load xla table from XLATAB lump.
//

void V_LoadXlaTable(void) {
    xlatab = W_CacheLumpName("XLATAB", PU_STATIC);
}

//
// V_DrawBlock
// Draw a linear block of pixels into the view buffer.
//

void V_DrawBlock(int x, int y, int width, int height, byte* src) {
    byte* dest;

#ifdef RANGECHECK
    if (x < 0 || x + width > SCREENWIDTH || y < 0 || y + height > SCREENHEIGHT) {
        I_Error("Bad V_DrawBlock");
    }
#endif

    V_MarkRect(x, y, width, height);

    dest = dest_screen + y * SCREENWIDTH + x;

    while (height--) {
        memcpy(dest, src, width);
        src += width;
        dest += SCREENWIDTH;
    }
}

void V_DrawFilledBox(int x, int y, int w, int h, int c) {
    uint8_t *buf, *buf1;
    int x1, y1;

    buf = I_VideoBuffer + SCREENWIDTH * y + x;

    for (y1 = 0; y1 < h; ++y1) {
        buf1 = buf;

        for (x1 = 0; x1 < w; ++x1) {
            *buf1++ = c;
        }

        buf += SCREENWIDTH;
    }
}

void V_DrawHorizLine(int x, int y, int w, int c) {
    uint8_t* buf;
    int x1;

    buf = I_VideoBuffer + SCREENWIDTH * y + x;

    for (x1 = 0; x1 < w; ++x1) {
        *buf++ = c;
    }
}

void V_DrawVertLine(int x, int y, int h, int c) {
    uint8_t* buf;
    int y1;

    buf = I_VideoBuffer + SCREENWIDTH * y + x;

    for (y1 = 0; y1 < h; ++y1) {
        *buf = c;
        buf += SCREENWIDTH;
    }
}

void V_DrawBox(int x, int y, int w, int h, int c) {
    V_DrawHorizLine(x, y, w, c);
    V_DrawHorizLine(x, y + h - 1, w, c);
    V_DrawVertLine(x, y, h, c);
    V_DrawVertLine(x + w - 1, y, h, c);
}

//
// Draw a "raw" screen (lump containing raw data to blit directly
// to the screen)
//

void V_DrawRawScreen(byte* raw) {
    memcpy(dest_screen, raw, SCREENWIDTH * SCREENHEIGHT);
}

//
// V_Init
//
void V_Init(void) {
    // no-op!
    // There used to be separate screens that could be drawn to; these are
    // now handled in the upper layers.
}

// Set the buffer that the code draws to.

void V_UseBuffer(byte* buffer) {
    dest_screen = buffer;
}

// Restore screen buffer to the i_video screen buffer.

void V_RestoreBuffer(void) {
    dest_screen = I_VideoBuffer;
}

//
// SCREEN SHOTS
//

typedef struct {
    char manufacturer;
    char version;
    char encoding;
    char bits_per_pixel;

    unsigned short xmin;
    unsigned short ymin;
    unsigned short xmax;
    unsigned short ymax;

    unsigned short hres;
    unsigned short vres;

    unsigned char palette[48];

    char reserved;
    char color_planes;
    unsigned short bytes_per_line;
    unsigned short palette_type;

    char filler[58];
    unsigned char data; // unbounded
} PACKEDATTR pcx_t;

//
// WritePCXfile
//

void WritePCXfile(char* filename, byte* data, int width, int height, byte* palette) {
    int i;
    int length;
    pcx_t* pcx;
    byte* pack;

    pcx = Z_Malloc(width * height * 2 + 1000, PU_STATIC, NULL);

    pcx->manufacturer = 0x0a; // PCX id
    pcx->version = 5;         // 256 color
    pcx->encoding = 1;        // uncompressed
    pcx->bits_per_pixel = 8;  // 256 color
    pcx->xmin = 0;
    pcx->ymin = 0;
    pcx->xmax = SHORT(width - 1);
    pcx->ymax = SHORT(height - 1);
    pcx->hres = SHORT(width);
    pcx->vres = SHORT(height);
    memset(pcx->palette, 0, sizeof(pcx->palette));
    pcx->color_planes = 1; // chunky image
    pcx->bytes_per_line = SHORT(width);
    pcx->palette_type = SHORT(2); // not a grey scale
    memset(pcx->filler, 0, sizeof(pcx->filler));

    // pack the image
    pack = &pcx->data;

    for (i = 0; i < width * height; i++) {
        if ((*data & 0xc0) != 0xc0)
            *pack++ = *data++;
        else {
            *pack++ = 0xc1;
            *pack++ = *data++;
        }
    }

    // write the palette
    *pack++ = 0x0c; // palette ID byte
    for (i = 0; i < 768; i++)
        *pack++ = *palette++;

    // write output file
    length = pack - (byte*) pcx;
    M_WriteFile(filename, pcx, length);

    Z_Free(pcx);
}

#ifdef HAVE_LIBPNG
//
// WritePNGfile
//

static void error_fn(png_structp p, png_const_charp s) {
    printf("libpng error: %s\n", s);
}

static void warning_fn(png_structp p, png_const_charp s) {
    printf("libpng warning: %s\n", s);
}

void WritePNGfile(char* filename, byte* data, int width, int height, byte* palette) {
    png_structp ppng;
    png_infop pinfo;
    png_colorp pcolor;
    FILE* handle;
    int i;

    handle = fopen(filename, "wb");
    if (!handle) {
        return;
    }

    ppng = png_create_write_struct(PNG_LIBPNG_VER_STRING, NULL, error_fn, warning_fn);
    if (!ppng) {
        return;
    }

    pinfo = png_create_info_struct(ppng);
    if (!pinfo) {
        png_destroy_write_struct(&ppng, NULL);
        return;
    }

    png_init_io(ppng, handle);

    png_set_IHDR(ppng, pinfo, width, height, 8, PNG_COLOR_TYPE_PALETTE, PNG_INTERLACE_NONE,
        PNG_COMPRESSION_TYPE_DEFAULT, PNG_FILTER_TYPE_DEFAULT);

    pcolor = malloc(sizeof(*pcolor) * 256);
    if (!pcolor) {
        png_destroy_write_struct(&ppng, &pinfo);
        return;
    }

    for (i = 0; i < 256; i++) {
        pcolor[i].red = *(palette + 3 * i);
        pcolor[i].green = *(palette + 3 * i + 1);
        pcolor[i].blue = *(palette + 3 * i + 2);
    }

    png_set_PLTE(ppng, pinfo, pcolor, 256);
    free(pcolor);

    png_write_info(ppng, pinfo);

    for (i = 0; i < SCREENHEIGHT; i++) {
        png_write_row(ppng, data + i * SCREENWIDTH);
    }

    png_write_end(ppng, pinfo);
    png_destroy_write_struct(&ppng, &pinfo);
    fclose(handle);
}
#endif

//
// V_ScreenShot
//

void V_ScreenShot(char* format) {
    int i;
    char lbmname[16]; // haleyjd 20110213: BUG FIX - 12 is too small!
    char* ext;

    // find a file name to save it to

#ifdef HAVE_LIBPNG
    extern int png_screenshots;
    if (png_screenshots) {
        ext = "png";
    } else
#endif
    {
        ext = "pcx";
    }

    for (i = 0; i <= 99; i++) {
        M_snprintf(lbmname, sizeof(lbmname), format, i, ext);

        if (!M_FileExists(lbmname)) {
            break; // file doesn't exist
        }
    }

    if (i == 100) {
        I_Error("V_ScreenShot: Couldn't create a PCX");
    }

#ifdef HAVE_LIBPNG
    if (png_screenshots) {
        WritePNGfile(lbmname, I_VideoBuffer, SCREENWIDTH, SCREENHEIGHT,
            W_CacheLumpName(DEH_String("PLAYPAL"), PU_CACHE));
    } else
#endif
    {
        // save the pcx file
        WritePCXfile(lbmname, I_VideoBuffer, SCREENWIDTH, SCREENHEIGHT,
            W_CacheLumpName(DEH_String("PLAYPAL"), PU_CACHE));
    }
}

#define MOUSE_SPEED_BOX_WIDTH 120
#define MOUSE_SPEED_BOX_HEIGHT 9

void V_DrawMouseSpeedBox(int speed) {
    extern int usemouse;
    int bgcolor, bordercolor, red, black, white, yellow;
    int box_x, box_y;
    int original_speed;
    int redline_x;
    int linelen;

    // Get palette indices for colors for widget. These depend on the
    // palette of the game being played.

    bgcolor = I_GetPaletteIndex(0x77, 0x77, 0x77);
    bordercolor = I_GetPaletteIndex(0x55, 0x55, 0x55);
    red = I_GetPaletteIndex(0xff, 0x00, 0x00);
    black = I_GetPaletteIndex(0x00, 0x00, 0x00);
    yellow = I_GetPaletteIndex(0xff, 0xff, 0x00);
    white = I_GetPaletteIndex(0xff, 0xff, 0xff);

    // If the mouse is turned off or acceleration is turned off, don't
    // draw the box at all.

    if (!usemouse || fabs(mouse_acceleration - 1) < 0.01) {
        return;
    }

    // Calculate box position

    box_x = SCREENWIDTH - MOUSE_SPEED_BOX_WIDTH - 10;
    box_y = 15;

    V_DrawFilledBox(box_x, box_y, MOUSE_SPEED_BOX_WIDTH, MOUSE_SPEED_BOX_HEIGHT, bgcolor);
    V_DrawBox(box_x, box_y, MOUSE_SPEED_BOX_WIDTH, MOUSE_SPEED_BOX_HEIGHT, bordercolor);

    // Calculate the position of the red line.  This is 1/3 of the way
    // along the box.

    redline_x = MOUSE_SPEED_BOX_WIDTH / 3;

    // Undo acceleration and get back the original mouse speed

    if (speed < mouse_threshold) {
        original_speed = speed;
    } else {
        original_speed = speed - mouse_threshold;
        original_speed = (int) (original_speed / mouse_acceleration);
        original_speed += mouse_threshold;
    }

    // Calculate line length

    linelen = (original_speed * redline_x) / mouse_threshold;

    // Draw horizontal "thermometer"

    if (linelen > MOUSE_SPEED_BOX_WIDTH - 1) {
        linelen = MOUSE_SPEED_BOX_WIDTH - 1;
    }

    V_DrawHorizLine(box_x + 1, box_y + 4, MOUSE_SPEED_BOX_WIDTH - 2, black);

    if (linelen < redline_x) {
        V_DrawHorizLine(box_x + 1, box_y + MOUSE_SPEED_BOX_HEIGHT / 2, linelen, white);
    } else {
        V_DrawHorizLine(box_x + 1, box_y + MOUSE_SPEED_BOX_HEIGHT / 2, redline_x, white);
        V_DrawHorizLine(box_x + redline_x, box_y + MOUSE_SPEED_BOX_HEIGHT / 2, linelen - redline_x, yellow);
    }

    // Draw red line

    V_DrawVertLine(box_x + redline_x, box_y + 1, MOUSE_SPEED_BOX_HEIGHT - 2, red);
}
