/*
 * 86Box	A hypervisor and IBM PC system emulator that specializes in
 *		running old operating systems and software designed for IBM
 *		PC systems and compatibles from 1981 through fairly recent
 *		system designs based on the PCI bus.
 *
 *		This file is part of the 86Box distribution.
 *
 *		Paradise VGA emulation
 *		 PC2086, PC3086 use PVGA1A
 *		 MegaPC uses W90C11A
 *
 *
 *
 * Authors:	Sarah Walker, <http://pcem-emulator.co.uk/>
 *		Miran Grca, <mgrca8@gmail.com>
 *
 *		Copyright 2008-2019 Sarah Walker.
 *		Copyright 2016-2019 Miran Grca.
 */
#include <stdio.h>
#include <stdint.h>
#include <string.h>
#include <stdlib.h>
#include <wchar.h>
#include <86box/86box.h>
#include <86box/io.h>
#include <86box/timer.h>
#include <86box/mem.h>
#include <86box/rom.h>
#include <86box/device.h>
#include <86box/video.h>
#include <86box/vid_svga.h>
#include <86box/vid_svga_render.h>


typedef struct paradise_t
{
        svga_t svga;
        
        rom_t bios_rom;
        
		uint8_t pr0a, pr0b, pr1, pr5, bank_mask;		
		
        enum
        {
                PVGA1A = 0,
                WD90C11,
		WD90C30
        } type;

		uint32_t vram_mask;

        uint32_t read_bank[4], write_bank[4];
		
		int interlace;
		
		struct {
			uint8_t reg_block_ptr;
			uint8_t reg_idx;
			uint8_t disable_autoinc;
			
			uint16_t int_status;
			uint16_t blt_ctrl1, blt_ctrl2;
			uint16_t srclow, srchigh;
			uint16_t dstlow, dsthigh;

			uint32_t srcaddr, dstaddr;
			
			int invalid_block;
		} accel;
} paradise_t;

static video_timings_t timing_paradise_pvga1a	= {VIDEO_ISA, 6,  8, 16,   6,  8, 16};
static video_timings_t timing_paradise_wd90c	= {VIDEO_ISA, 3,  3,  6,   5,  5, 10};

void paradise_remap(paradise_t *paradise);

void paradise_out(uint16_t addr, uint8_t val, void *p)
{
        paradise_t *paradise = (paradise_t *)p;
        svga_t *svga = &paradise->svga;
        uint8_t old, o;
		
		if (paradise->vram_mask <= ((512 << 10) - 1))
			paradise->bank_mask = 0x7f;
		else
			paradise->bank_mask = 0xff;
	
        if (((addr & 0xfff0) == 0x3d0 || (addr & 0xfff0) == 0x3b0) && !(svga->miscout & 1)) 
                addr ^= 0x60;

        switch (addr)
        {
                case 0x3c5:
                if (svga->seqaddr > 7) 
                {
                        if (paradise->type < WD90C11 || svga->seqregs[6] != 0x48) 
							return;
                        svga->seqregs[svga->seqaddr & 0x1f] = val;
                        if (svga->seqaddr == 0x11) {
							paradise_remap(paradise);
						}
                        return;
                }
                break;

                case 0x3cf:
                if (svga->gdcaddr >= 9 && svga->gdcaddr <= 0x0e) {
					if ((paradise->pr5 & 7) != 5)
						return;
                }
				switch (svga->gdcaddr) {
					case 6:
						if (val & 8)
							svga->banked_mask = 0x7fff;
						else
							svga->banked_mask = 0xffff;
						if (svga->gdcreg[6] != val)
							svga->gdcreg[6] = val;
						paradise_remap(paradise);
						break;
					
					case 9:
						paradise->pr0a = val & paradise->bank_mask;
						paradise_remap(paradise);
						break;
					case 0x0a:
						paradise->pr0b = val & paradise->bank_mask;
						paradise_remap(paradise);
						break;
					case 0x0b:
						paradise->pr1 = val;
						paradise_remap(paradise);
						break;
					case 0x0d:
						o = svga->gdcreg[0x0d];
						svga->gdcreg[0x0d] = val;
						if ((o ^ val) & 0x18)
							svga_recalctimings(svga);
						break;
					case 0x0e:
						o = svga->gdcreg[0x0e];
						svga->gdcreg[0x0e] = val;
						if ((o ^ val) & 0x01)
							svga_recalctimings(svga);
						break;
					case 0x0c:
						svga->gdcreg[0x0c] = val;
						break;
					case 0x0f:
						paradise->pr5 = val;
						break;
					default:
						svga->gdcreg[svga->gdcaddr] = val;
						break;
				}
                break;
                
                case 0x3D4:
                svga->crtcreg = val & 0x3f;
                return;
                case 0x3D5:
                if ((paradise->type == PVGA1A) && (svga->crtcreg & 0x20))
                        return;
                if ((svga->crtcreg < 7) && (svga->crtc[0x11] & 0x80))
                        return;
                if ((svga->crtcreg == 7) && (svga->crtc[0x11] & 0x80))
                        val = (svga->crtc[7] & ~0x10) | (val & 0x10);
                if (svga->crtcreg > 0x29 && (svga->crtc[0x29] & 7) != 5)
                   return;
                if (svga->crtcreg >= 0x31 && svga->crtcreg <= 0x37)
                   return;
                old = svga->crtc[svga->crtcreg];
                svga->crtc[svga->crtcreg] = val;
				
                if (old != val)
                {
                        if (svga->crtcreg < 0xe || svga->crtcreg > 0x10)
                        {
				if ((svga->crtcreg == 0xc) || (svga->crtcreg == 0xd)) {
                                	svga->fullchange = 3;
					svga->ma_latch = ((svga->crtc[0xc] << 8) | svga->crtc[0xd]) + ((svga->crtc[8] & 0x60) >> 5);
				} else {
					svga->fullchange = changeframecount;
	                                svga_recalctimings(svga);
				}
                        }
                }
                break;
        }
		
		svga_out(addr, val, svga);
}

uint8_t paradise_in(uint16_t addr, void *p)
{
        paradise_t *paradise = (paradise_t *)p;
        svga_t *svga = &paradise->svga;
        
        if (((addr & 0xfff0) == 0x3d0 || (addr & 0xfff0) == 0x3b0) && !(svga->miscout & 1))
                addr ^= 0x60;
        
        switch (addr)
        {
                case 0x3c5:
                if (svga->seqaddr > 7)
                {
                        if (paradise->type < WD90C11 || svga->seqregs[6] != 0x48) 
							return 0xff;
						if (paradise->type < WD90C30) {
							if (svga->seqaddr > 0x12) 
								return 0xff;
						}
                        return svga->seqregs[svga->seqaddr & 0x1f];
                }
                break;
                        
                case 0x3cf:
                if (svga->gdcaddr >= 9 && svga->gdcaddr <= 0x0e) {
					if ((paradise->pr5 & 7) != 5)
						return 0xff;
                }
				switch (svga->gdcaddr) {
					case 9:
						return paradise->pr0a;
					case 0x0a:
						return paradise->pr0b;
					case 0x0b:
						if (paradise->vram_mask == (512 << 10) - 1) {
							paradise->pr1 |= 0xc0;
							paradise->pr1 &= ~0x40;
						} else if (paradise->vram_mask == (1024 << 10) - 1) {
							paradise->pr1 |= 0xc0;
							if (svga->bpp >= 8 && !svga->lowres) /*Horrible tweak, but needed to get around black corruption in 1M mode*/
								paradise->pr1 &= ~0x40;
						}
						return paradise->pr1;
					case 6:
					case 0x0c:
					case 0x0d:
					case 0x0e:
						return svga->gdcreg[svga->gdcaddr];
					case 0x0f:
						return (paradise->pr5 & 0x17) | 0x80;
					default:
						return svga->gdcreg[svga->gdcaddr];
				}
                break;

                case 0x3D4:
                return svga->crtcreg;
                case 0x3D5:
                if ((paradise->type == PVGA1A) && (svga->crtcreg & 0x20))
					return 0xff;				
                if (svga->crtcreg > 0x29 && svga->crtcreg < 0x30 && (svga->crtc[0x29] & 0x88) != 0x80)
					return 0xff;
                return svga->crtc[svga->crtcreg];
        }
        return svga_in(addr, svga);
}

void paradise_remap(paradise_t *paradise)
{
        svga_t *svga = &paradise->svga;

        if (svga->seqregs[0x11] & 0x80) {
			paradise->read_bank[0] = (paradise->pr0a) << 12;
			paradise->read_bank[1] = paradise->read_bank[0] + ((svga->gdcreg[6] & 8) ? 0 : 0x8000);
			paradise->read_bank[2] = paradise->read_bank[0];
			paradise->read_bank[3] = paradise->read_bank[1];
			paradise->write_bank[0] = (paradise->pr0b) << 12;
			paradise->write_bank[1] = paradise->write_bank[0] + ((svga->gdcreg[6] & 8) ? 0 : 0x8000);
			paradise->write_bank[2] = paradise->write_bank[0];
			paradise->write_bank[3] = paradise->write_bank[1];
		 } else if (paradise->pr1 & 8) {
			if (svga->gdcreg[6] & 0x0c) {
				paradise->read_bank[0] = (paradise->pr0b) << 12;
				paradise->read_bank[1] = ((paradise->pr0a) << 12) + ((svga->gdcreg[6] & 8) ? 0 : 0x8000);
				paradise->read_bank[2] = paradise->read_bank[0];
				paradise->read_bank[3] = paradise->read_bank[1];
				paradise->write_bank[0] = (paradise->pr0b) << 12;
				paradise->write_bank[1] = ((paradise->pr0a) << 12) + ((svga->gdcreg[6] & 8) ? 0 : 0x8000);
				paradise->write_bank[2] = paradise->write_bank[0];
				paradise->write_bank[3] = paradise->write_bank[1];
			} else {
				paradise->read_bank[0] = (paradise->pr0b) << 12;
				paradise->read_bank[1] = paradise->read_bank[0] + ((svga->gdcreg[6] & 8) ? 0 : 0x8000);
				paradise->read_bank[2] = (paradise->pr0a) << 12;
				paradise->read_bank[3] = paradise->read_bank[2] + ((svga->gdcreg[6] & 8) ? 0 : 0x8000);				
				paradise->write_bank[0] = (paradise->pr0b) << 12;
				paradise->write_bank[1] = paradise->write_bank[0] + ((svga->gdcreg[6] & 8) ? 0 : 0x8000);
				paradise->write_bank[2] = (paradise->pr0a) << 12;
				paradise->write_bank[3] = paradise->write_bank[2] + ((svga->gdcreg[6] & 8) ? 0 : 0x8000);
			}
        } else {
			paradise->read_bank[0] = (paradise->pr0a) << 12;
			paradise->write_bank[0] = (paradise->pr0a) << 12;
			paradise->read_bank[1] = paradise->read_bank[0] + ((svga->gdcreg[6] & 8) ? 0 : 0x8000);
			paradise->write_bank[1] = paradise->write_bank[0] + ((svga->gdcreg[6] & 8) ? 0 : 0x8000);
			paradise->read_bank[2] = paradise->read_bank[0];
			paradise->write_bank[2] = paradise->write_bank[0];
			paradise->read_bank[3] = paradise->read_bank[0] + ((svga->gdcreg[6] & 8) ? 0 : 0x8000);
			paradise->write_bank[3] = paradise->write_bank[0] + ((svga->gdcreg[6] & 8) ? 0 : 0x8000);
		}
		
		if (paradise->bank_mask == 0x7f) {
			paradise->read_bank[1] &= 0x7ffff;
			paradise->write_bank[1] &= 0x7ffff;
		}
}

void paradise_recalctimings(svga_t *svga)
{
	paradise_t *paradise = (paradise_t *) svga->p;

	if (svga->gdcreg[0x0d] & 0x08) svga->ma_latch |= 0x10000;
	if (svga->gdcreg[0x0d] & 0x10) svga->ma_latch |= 0x20000;

	svga->lowres = !(svga->gdcreg[0x0e] & 0x01);

	if (paradise->type == WD90C30) {
		if (svga->crtc[0x3e] & 0x01) svga->vtotal |= 0x400;
		if (svga->crtc[0x3e] & 0x02) svga->dispend |= 0x400;
		if (svga->crtc[0x3e] & 0x04) svga->vsyncstart |= 0x400;
		if (svga->crtc[0x3e] & 0x08) svga->vblankstart |= 0x400;
		if (svga->crtc[0x3e] & 0x10) svga->split |= 0x400;

		svga->interlace = !!(svga->crtc[0x2d] & 0x20);
		
		if (!svga->interlace && svga->lowres && (svga->hdisp >= 1024) && 
			((svga->gdcreg[5] & 0x60) == 0) && (svga->miscout >= 0x27) && 
			(svga->miscout <= 0x2f) && ((svga->gdcreg[6] & 1) || 
			(svga->attrregs[0x10] & 1))) { /*Horrible tweak to re-enable the interlace after returning to
											 a windowed DOS box in Win3.x*/
			svga->interlace = 1;
		}
	}

	if (svga->bpp >= 8 && !svga->lowres)
		svga->render = svga_render_8bpp_highres;
}

static void paradise_write(uint32_t addr, uint8_t val, void *p)
{
        paradise_t *paradise = (paradise_t *)p;
		svga_t *svga = &paradise->svga;

		addr &= svga->banked_mask;
		addr = (addr & 0x7fff) + paradise->write_bank[(addr >> 15) & 3];
		
		svga_write_linear(addr, val, svga);
}
static void paradise_writew(uint32_t addr, uint16_t val, void *p)
{
        paradise_t *paradise = (paradise_t *)p;
		svga_t *svga = &paradise->svga;

		addr &= svga->banked_mask;
		addr = (addr & 0x7fff) + paradise->write_bank[(addr >> 15) & 3];

		svga_writew_linear(addr, val, svga);
}

static uint8_t paradise_read(uint32_t addr, void *p)
{
        paradise_t *paradise = (paradise_t *)p;
		svga_t *svga = &paradise->svga;

		addr &= svga->banked_mask;
		addr = (addr & 0x7fff) + paradise->read_bank[(addr >> 15) & 3];

		return svga_read_linear(addr, svga);
}
static uint16_t paradise_readw(uint32_t addr, void *p)
{
        paradise_t *paradise = (paradise_t *)p;
		svga_t *svga = &paradise->svga;

		addr &= svga->banked_mask;
		addr = (addr & 0x7fff) + paradise->read_bank[(addr >> 15) & 3];

        return svga_readw_linear(addr, svga);
}

void *paradise_init(const device_t *info, uint32_t memsize)
{
        paradise_t *paradise = malloc(sizeof(paradise_t));
        svga_t *svga = &paradise->svga;
        memset(paradise, 0, sizeof(paradise_t));

	if (info->local == PVGA1A)
		video_inform(VIDEO_FLAG_TYPE_SPECIAL, &timing_paradise_pvga1a);
	else
		video_inform(VIDEO_FLAG_TYPE_SPECIAL, &timing_paradise_wd90c);

	switch(info->local) {
		case PVGA1A:
			svga_init(info, svga, paradise, memsize, /*256kb*/
				   paradise_recalctimings,
				   paradise_in, paradise_out,
				   NULL,
				   NULL);
			paradise->vram_mask = memsize - 1;
			svga->decode_mask = memsize - 1;
			break;
		case WD90C11:
			svga_init(info, svga, paradise, 1 << 19, /*512kb*/
				   paradise_recalctimings,
				   paradise_in, paradise_out,
				   NULL,
				   NULL);
			paradise->vram_mask = (1 << 19) - 1;
			svga->decode_mask = (1 << 19) - 1;
			break;
		case WD90C30:
			svga_init(info, svga, paradise, memsize,
				   paradise_recalctimings,
				   paradise_in, paradise_out,
				   NULL,
				   NULL);
			paradise->vram_mask = memsize - 1;
			svga->decode_mask = memsize - 1;
			break;
	}
	
	mem_mapping_set_handler(&svga->mapping, paradise_read, paradise_readw, NULL, paradise_write, paradise_writew, NULL);
	mem_mapping_set_p(&svga->mapping, paradise);

	io_sethandler(0x03c0, 0x0020, paradise_in, NULL, NULL, paradise_out, NULL, NULL, paradise);

	/* Common to all three types. */
	svga->crtc[0x31] = 'W';
	svga->crtc[0x32] = 'D';
	svga->crtc[0x33] = '9';
	svga->crtc[0x34] = '0';
	svga->crtc[0x35] = 'C';

	switch(info->local) {
		case WD90C11:
			svga->crtc[0x36] = '1';
			svga->crtc[0x37] = '1';
			break;
		case WD90C30:
			svga->crtc[0x36] = '3';
			svga->crtc[0x37] = '0';
			break;
	}

	svga->bpp = 8;
	svga->miscout = 1;

	paradise->type = info->local;
        
	return paradise;
}

static void *paradise_pvga1a_ncr3302_init(const device_t *info)
{
        paradise_t *paradise = paradise_init(info, 1 << 18);
        
        if (paradise)
                rom_init(&paradise->bios_rom, "roms/machines/ncr_3302/c000-wd_1987-1989-740011-003058-019c.bin", 0xc0000, 0x8000, 0x7fff, 0, MEM_MAPPING_EXTERNAL);
                
        return paradise;
}

static void *paradise_pvga1a_pc2086_init(const device_t *info)
{
        paradise_t *paradise = paradise_init(info, 1 << 18);
        
        if (paradise)
                rom_init(&paradise->bios_rom, "roms/machines/pc2086/40186.ic171", 0xc0000, 0x8000, 0x7fff, 0, MEM_MAPPING_EXTERNAL);
                
        return paradise;
}

static void *paradise_pvga1a_pc3086_init(const device_t *info)
{
        paradise_t *paradise = paradise_init(info, 1 << 18);

        if (paradise)
                rom_init(&paradise->bios_rom, "roms/machines/pc3086/c000.bin", 0xc0000, 0x8000, 0x7fff, 0, MEM_MAPPING_EXTERNAL);
                
        return paradise;
}

static void *paradise_pvga1a_standalone_init(const device_t *info)
{
        paradise_t *paradise;
	uint32_t memory = 512;

	memory = device_get_config_int("memory");
	memory <<= 10;

        paradise = paradise_init(info, memory);
        
        if (paradise)
                rom_init(&paradise->bios_rom, "roms/video/pvga1a/BIOS.BIN", 0xc0000, 0x8000, 0x7fff, 0, MEM_MAPPING_EXTERNAL);
        
        return paradise;
}

static int paradise_pvga1a_standalone_available(void)
{
        return rom_present("roms/video/pvga1a/BIOS.BIN");
}

static void *paradise_wd90c11_megapc_init(const device_t *info)
{
        paradise_t *paradise = paradise_init(info, 0);
        
        if (paradise)
                rom_init_interleaved(&paradise->bios_rom,
                                     "roms/machines/megapc/41651-bios lo.u18",
                                     "roms/machines/megapc/211253-bios hi.u19",
                                     0xc0000, 0x8000, 0x7fff, 0, MEM_MAPPING_EXTERNAL);
        
        return paradise;
}

static void *paradise_wd90c11_standalone_init(const device_t *info)
{
        paradise_t *paradise = paradise_init(info, 0);
        
        if (paradise)
                rom_init(&paradise->bios_rom, "roms/video/wd90c11/WD90C11.VBI", 0xc0000, 0x8000, 0x7fff, 0, MEM_MAPPING_EXTERNAL);
        
        return paradise;
}

static int paradise_wd90c11_standalone_available(void)
{
        return rom_present("roms/video/wd90c11/WD90C11.VBI");
}

static void *paradise_wd90c30_standalone_init(const device_t *info)
{
        paradise_t *paradise;
	uint32_t memory = 512;

	memory = device_get_config_int("memory");
	memory <<= 10;

        paradise = paradise_init(info, memory);
        
        if (paradise)
                rom_init(&paradise->bios_rom, "roms/video/wd90c30/90C30-LR.VBI", 0xc0000, 0x8000, 0x7fff, 0, MEM_MAPPING_EXTERNAL);

        return paradise;
}

static int paradise_wd90c30_standalone_available(void)
{
        return rom_present("roms/video/wd90c30/90C30-LR.VBI");
}

void paradise_close(void *p)
{
        paradise_t *paradise = (paradise_t *)p;

        svga_close(&paradise->svga);
        
        free(paradise);
}

void paradise_speed_changed(void *p)
{
        paradise_t *paradise = (paradise_t *)p;
        
        svga_recalctimings(&paradise->svga);
}

void paradise_force_redraw(void *p)
{
        paradise_t *paradise = (paradise_t *)p;

        paradise->svga.fullchange = changeframecount;
}

const device_t paradise_pvga1a_pc2086_device =
{
        "Paradise PVGA1A (Amstrad PC2086)",
        0,
	PVGA1A,
        paradise_pvga1a_pc2086_init,
        paradise_close,
        NULL,
	{ NULL },
        paradise_speed_changed,
        paradise_force_redraw,
	NULL
};

const device_t paradise_pvga1a_pc3086_device =
{
        "Paradise PVGA1A (Amstrad PC3086)",
        0,
	PVGA1A,
        paradise_pvga1a_pc3086_init,
        paradise_close,
	NULL,
        { NULL },
        paradise_speed_changed,
        paradise_force_redraw,
	NULL
};

static const device_config_t paradise_pvga1a_config[] =
{
        {
                "memory", "Memory size", CONFIG_SELECTION, "", 512, "", { 0 },
                {
                        {
                                "256 kB", 256
                        },
                        {
                                "512 kB", 512
                        },
                        {
                                "1 MB", 1024
                        },
                        {
                                ""
                        }
                }
        },
        {
                "", "", -1
        }
};

const device_t paradise_pvga1a_ncr3302_device =
{
        "Paradise PVGA1A (NCR 3302)",
        0,
	PVGA1A,
        paradise_pvga1a_ncr3302_init,
        paradise_close,
        NULL,
	{ NULL },
        paradise_speed_changed,
        paradise_force_redraw,
	paradise_pvga1a_config
};

const device_t paradise_pvga1a_device =
{
        "Paradise PVGA1A",
        DEVICE_ISA,
	PVGA1A,
        paradise_pvga1a_standalone_init,
        paradise_close,
	NULL,
        { paradise_pvga1a_standalone_available },
        paradise_speed_changed,
        paradise_force_redraw,
	paradise_pvga1a_config
};
const device_t paradise_wd90c11_megapc_device =
{
        "Paradise WD90C11 (Amstrad MegaPC)",
        0,
	WD90C11,
        paradise_wd90c11_megapc_init,
        paradise_close,
	NULL,
        { NULL },
        paradise_speed_changed,
        paradise_force_redraw,
	NULL
};
const device_t paradise_wd90c11_device =
{
        "Paradise WD90C11-LR",
        DEVICE_ISA,
	WD90C11,
        paradise_wd90c11_standalone_init,
        paradise_close,
	NULL,
        { paradise_wd90c11_standalone_available },
        paradise_speed_changed,
        paradise_force_redraw,
	NULL
};

static const device_config_t paradise_wd90c30_config[] =
{
        {
                "memory", "Memory size", CONFIG_SELECTION, "", 1024, "", { 0 },
                {
                        {
                                "512 kB", 512
                        },
                        {
                                "1 MB", 1024
                        },
                        {
                                ""
                        }
                }
        },
        {
                "", "", -1
        }
};

const device_t paradise_wd90c30_device =
{
        "Paradise WD90C30-LR",
        DEVICE_ISA,
	WD90C30,
        paradise_wd90c30_standalone_init,
        paradise_close,
	NULL,
        { paradise_wd90c30_standalone_available },
        paradise_speed_changed,
        paradise_force_redraw,
	paradise_wd90c30_config
};