#include <stdio.h>
#include <stdint.h>
#include <stdlib.h>
#include <string.h>
#include "ncr.h"
#include "hd.h"
#include "esp_partition.h"
#include "hexdump.h"

typedef struct {
	const esp_partition_t* part;
	int size;
} HdPriv;

const uint8_t inq_resp[95]={
	0, //HD
	0, //0x80 if removable
	0x49, //Obsolete SCSI standard 1 all the way
	0, //response version etc
	31, //extra data
	0,0, //reserved
	0, //features
	'A','P','P','L','E',' ',' ',' ', //vendor id
	'2','0','S','C',' ',' ',' ',' ', //prod id
	'1','.','0',' ',' ',' ',' ',' ', //prod rev lvl
};

static void writeSector(HdPriv *hd, unsigned int lba, uint8_t *data) {
	uint8_t *secdat=malloc(4096);
	assert(secdat);
	unsigned int lbaStart=lba&(~7);
	unsigned int lbaOff=lba&7;
	assert(esp_partition_read(hd->part, lbaStart*512, secdat, 4096)==ESP_OK);
	assert(esp_partition_erase_range(hd->part, lbaStart*512, 4096)==ESP_OK);
	for (int i=0; i<512; i++) secdat[lbaOff*512+i]=data[i];
	assert(esp_partition_write(hd->part, lbaStart*512, secdat, 4096)==ESP_OK);
	free(secdat);
}

static int hdScsiCmd(SCSITransferData *data, unsigned int cmd, unsigned int len, unsigned int lba, void *arg) {
	int ret=0;
	static uint8_t *bb=NULL;
	HdPriv *hd=(HdPriv*)arg;
	if (cmd==0x8 || cmd==0x28) { //read
		printf("HD: Read %d bytes from LBA %d.\n", len*512, lba);
		assert(esp_partition_read(hd->part, lba*512, data->data, len*512)==ESP_OK);
#if 0 
		//alternate mmap solution
		uint8_t *buf;
		spi_flash_mmap_handle_t handle;
		esp_partition_mmap(hd->part, lba*512, len*512, SPI_FLASH_MMAP_DATA, &buf, &handle);
		memcpy(data->data, buf, len*512);
		spi_flash_munmap(handle);
#endif
//		hexdump(data->data, len*512);
		ret=len*512;
	} else if (cmd==0x0A || cmd==0x2A) { //write
		uint8_t *dp=data->data;
		while(len) {
			writeSector(hd, lba, dp);
			lba++;
			dp+=512;
			len--;
		}
		ret=0;
	} else if (cmd==0x12) { //inquiry
		printf("HD: Inquery\n");
		memcpy(data->data, inq_resp, sizeof(inq_resp));
		return 95;
	} else if (cmd==0x25) { //read capacity
		int lbacnt=hd->size/512;
		data->data[0]=(lbacnt>>24);
		data->data[1]=(lbacnt>>16);
		data->data[2]=(lbacnt>>8);
		data->data[3]=(lbacnt>>0);
		data->data[4]=0;
		data->data[5]=0;
		data->data[6]=2; //512
		data->data[7]=0;
		ret=8;
		printf("HD: Read capacity (%d)\n", lbacnt);
	} else {
		printf("********** hdScsiCmd: unrecognized command %x\n", cmd);
	}
	data->cmd[0]=0; //status
	data->msg[0]=0;
	return ret;
}

SCSIDevice *hdCreate(char *file) {
	SCSIDevice *ret=malloc(sizeof(SCSIDevice));
	memset(ret, 0, sizeof(SCSIDevice));
	HdPriv *hd=malloc(sizeof(HdPriv));
	memset(hd, 0, sizeof(HdPriv));
	hd->part=esp_partition_find_first(0x40, 0x2, NULL);
	if (hd->part==0) printf("Couldn't find HD part!\n");
	hd->size=hd->part->size;
	ret->arg=hd;
	ret->scsiCmd=hdScsiCmd;
	return ret;
}