/*PC1640 video emulation.
  Mostly standard EGA, but with CGA & Hercules emulation*/
#include <stdlib.h>
#include "ibm.h"
#include "device.h"
#include "io.h"
#include "mem.h"
#include "rom.h"
#include "timer.h"
#include "video.h"
#include "vid_cga.h"
#include "vid_ega.h"
#include "vid_pc1640.h"

typedef struct pc1640_t {
	mem_mapping_t cga_mapping;
	mem_mapping_t ega_mapping;

	cga_t cga;
	ega_t ega;

	rom_t bios_rom;

	int cga_enabled;
	uint64_t dispontime, dispofftime;
	pc_timer_t timer;
} pc1640_t;

void pc1640_out(uint16_t addr, uint8_t val, void *p) {
	pc1640_t *pc1640 = (pc1640_t *)p;

	switch (addr) {
	case 0x3db:
		if (pc1640->cga_enabled != (val & 0x40)) {
			pc1640->cga_enabled = val & 0x40;
			if (pc1640->cga_enabled) {
				timer_disable(&pc1640->ega.timer);
				timer_set_delay_u64(&pc1640->cga.timer, 0);
				mem_mapping_enable(&pc1640->cga_mapping);
				mem_mapping_disable(&pc1640->ega_mapping);
			} else {
				timer_disable(&pc1640->cga.timer);
				timer_set_delay_u64(&pc1640->ega.timer, 0);
				mem_mapping_disable(&pc1640->cga_mapping);
				switch (pc1640->ega.gdcreg[6] & 0xc) {
				case 0x0: /*128k at A0000*/
					mem_mapping_set_addr(&pc1640->ega_mapping, 0xa0000, 0x20000);
					break;
				case 0x4: /*64k at A0000*/
					mem_mapping_set_addr(&pc1640->ega_mapping, 0xa0000, 0x10000);
					break;
				case 0x8: /*32k at B0000*/
					mem_mapping_set_addr(&pc1640->ega_mapping, 0xb0000, 0x08000);
					break;
				case 0xC: /*32k at B8000*/
					mem_mapping_set_addr(&pc1640->ega_mapping, 0xb8000, 0x08000);
					break;
				}
			}
		}
		pclog("3DB write %02X\n", val);
		return;
	}
	if (pc1640->cga_enabled)
		cga_out(addr, val, &pc1640->cga);
	else
		ega_out(addr, val, &pc1640->ega);
}

uint8_t pc1640_in(uint16_t addr, void *p) {
	pc1640_t *pc1640 = (pc1640_t *)p;

	switch (addr) {
	}

	if (pc1640->cga_enabled)
		return cga_in(addr, &pc1640->cga);
	else
		return ega_in(addr, &pc1640->ega);
}

void pc1640_recalctimings(pc1640_t *pc1640) {
	cga_recalctimings(&pc1640->cga);
	ega_recalctimings(&pc1640->ega);
	if (pc1640->cga_enabled) {
		pc1640->dispontime = pc1640->cga.dispontime;
		pc1640->dispofftime = pc1640->cga.dispofftime;
	} else {
		pc1640->dispontime = pc1640->ega.dispontime;
		pc1640->dispofftime = pc1640->ega.dispofftime;
	}
}

void *pc1640_init() {
	pc1640_t *pc1640 = malloc(sizeof(pc1640_t));
	cga_t *cga = &pc1640->cga;
	ega_t *ega = &pc1640->ega;
	memset(pc1640, 0, sizeof(pc1640_t));

	rom_init(&pc1640->bios_rom, "pc1640/40100", 0xc0000, 0x8000, 0x7fff, 0, 0);

	ega_init(&pc1640->ega, 9, 0);
	pc1640->cga.vram = pc1640->ega.vram;
	pc1640->cga_enabled = 1;
	cga_init(&pc1640->cga);
	timer_disable(&pc1640->ega.timer);

	mem_mapping_add(&pc1640->cga_mapping, 0xb8000, 0x08000, cga_read, NULL, NULL, cga_write, NULL, NULL, NULL, 0, cga);
	mem_mapping_add(&pc1640->ega_mapping, 0, 0, ega_read, NULL, NULL, ega_write, NULL, NULL, NULL, 0, ega);
	io_sethandler(0x03a0, 0x0040, pc1640_in, NULL, NULL, pc1640_out, NULL, NULL, pc1640);
	return pc1640;
}

void pc1640_close(void *p) {
	pc1640_t *pc1640 = (pc1640_t *)p;

	free(pc1640->ega.vram);
	free(pc1640);
}

void pc1640_speed_changed(void *p) {
	pc1640_t *pc1640 = (pc1640_t *)p;

	pc1640_recalctimings(pc1640);
}

device_t pc1640_device =
	{
		"Amstrad PC1640 (video)",
		0,
		pc1640_init,
		pc1640_close,
		NULL,
		pc1640_speed_changed,
		NULL,
		NULL
	};
