#include <stdlib.h>
#include <stdarg.h>
#include <stdio.h>

#include "eve.h"

#define EVE_MEM_WRITE           0x800000

static char _cmd_burst;
static uint16_t _cmd_offset;
static uint32_t _dl_addr;

void eve_command(uint8_t command, uint8_t parameter) {
    eve_spi_cs_set();
    eve_spi_xchg24(((uint32_t)command << 16) | ((uint32_t)parameter << 8), 0);
    eve_spi_cs_clear();
}

uint8_t eve_read8(uint32_t addr) {
    uint8_t r;
    eve_spi_cs_set();
    eve_spi_xchg32(addr << 8, 0);
    r = eve_spi_xchg8(0, EVE_SPI_FLAG_BSWAP);
    eve_spi_cs_clear();

    return r;
}

uint16_t eve_read16(uint32_t addr) {
    uint16_t r;
    eve_spi_cs_set();
    eve_spi_xchg32(addr << 8, 0);
    r = eve_spi_xchg16(0, EVE_SPI_FLAG_BSWAP);
    eve_spi_cs_clear();

    return r;
}

uint32_t eve_read32(uint32_t addr) {
    uint32_t r;
    eve_spi_cs_set();
    eve_spi_xchg32(addr << 8, 0);
    r = eve_spi_xchg32(0, EVE_SPI_FLAG_BSWAP);
    eve_spi_cs_clear();

    return r;
}

void eve_write8(uint32_t addr, uint8_t data) {
    eve_spi_cs_set();
    eve_spi_xchg24(addr | EVE_MEM_WRITE, 0);
    eve_spi_xchg8(data, EVE_SPI_FLAG_BSWAP);
    eve_spi_cs_clear();
}

void eve_write16(uint32_t addr, uint16_t data) {
    eve_spi_cs_set();
    eve_spi_xchg24(addr | EVE_MEM_WRITE, 0);
    eve_spi_xchg16(data, EVE_SPI_FLAG_BSWAP);
    eve_spi_cs_clear();
}

void eve_write32(uint32_t addr, uint32_t data) {
    eve_spi_cs_set();
    eve_spi_xchg24(addr | EVE_MEM_WRITE, 0);
    eve_spi_xchg32(data, EVE_SPI_FLAG_BSWAP);
    eve_spi_cs_clear();
}

void eve_active(void) {
    eve_command(EVE_ACTIVE, 0);
}

void eve_brightness(uint8_t b) {
	eve_write8(REG_PWM_DUTY, b);
}

static void _dl_inc(uint32_t i) {
	_dl_addr += i;
}

void eve_dl_start(uint32_t addr) {
    _dl_addr = addr;
}

void eve_dl_write(uint32_t dl) {
    eve_write32(_dl_addr, dl);
    _dl_inc(4);
}

void eve_dl_swap(void) {
    eve_write8(REG_DLSWAP, EVE_DLSWAP_FRAME);
}

uint32_t eve_dl_get_addr(void) {
    return _dl_addr;
}

static void _cmd_inc(uint16_t i) {
	_cmd_offset += i;
	_cmd_offset &= 0x0fff;
}

static void _cmd_begin(uint32_t command) {
    uint8_t flags = 0;

    if (_cmd_burst) {
        flags = EVE_SPI_FLAG_TX;
    } else {
    	uint32_t addr = EVE_RAM_CMD + _cmd_offset;
        eve_spi_cs_set();
        eve_spi_xchg24(addr | EVE_MEM_WRITE, 0);
    }
    eve_spi_xchg32(command, EVE_SPI_FLAG_BSWAP | flags);
    _cmd_inc(4);
}

static void _cmd_end(void) {
    if (!_cmd_burst) eve_spi_cs_clear();
}

static void _cmd_string(const char *s, uint8_t flags) {
    int i = 0;

    while (s[i] != 0) {
        eve_spi_xchg8(s[i], flags);
        i++;
    }
    eve_spi_xchg8(0, flags);
    i++;
    _cmd_inc(i);
}

static void _cmd_buffer(const char *b, int size, uint8_t flags) {
    int i = 0;

    for (i=0; i<size; i++) {
        eve_spi_xchg8(b[i], flags);
    }
    _cmd_inc(size);
}

void eve_cmd(uint32_t cmd, const char *fmt, ...) {
    uint8_t flags = _cmd_burst ? (EVE_SPI_FLAG_TX | EVE_SPI_FLAG_BSWAP) : EVE_SPI_FLAG_BSWAP;
    va_list argv;
    uint16_t *p;
    int i = 0;

    va_start(argv, fmt);
    _cmd_begin(cmd);
    while (fmt[i]) {
        switch (fmt[i]) {
            case 'b':
                eve_spi_xchg8(va_arg(argv, int), flags);
                _cmd_inc(1);
                break;
            case 'h':
                eve_spi_xchg16(va_arg(argv, int), flags);
                _cmd_inc(2);
                break;
            case 'w':
                eve_spi_xchg32(va_arg(argv, int), flags);
                _cmd_inc(4);
                break;
            case '&':
                p = va_arg(argv, uint16_t *);
                *p = _cmd_offset;
                eve_spi_xchg32(0, flags);
                _cmd_inc(4);
                break;
            case 's':
                _cmd_string(va_arg(argv, const char *), flags);
                break;
            case 'p':
                _cmd_buffer(va_arg(argv, const char *), va_arg(argv, int), flags);
                break;
        }
        i++;
    }
	va_end(argv);
    /* padding */
	i = _cmd_offset & 3;  /* equivalent to _cmd_offset % 4 */
    if (i) {
    	i = 4 - i;  /* 3, 2 or 1 */
        _cmd_inc(i);

    	while (i > 0) {
            eve_spi_xchg8(0, flags);
    		i--;
    	}
    }
    _cmd_end();
}

uint32_t eve_cmd_result(uint16_t offset) {
    return eve_read32(EVE_RAM_CMD + offset);
}

void eve_cmd_dl(uint32_t dl) {
    _cmd_begin(dl);
    _cmd_end();
}

int eve_cmd_done(void) {
	uint16_t r = eve_read16(REG_CMD_READ);
    if (r == 0xfff) {
		_cmd_offset = 0;
		eve_write8(REG_CPURESET, 1);
		eve_write16(REG_CMD_READ, 0);
		eve_write16(REG_CMD_WRITE, 0);
		eve_write16(REG_CMD_DL, 0);
		eve_write8(REG_CPURESET, 0);
        return -1;
    }
    return (r == _cmd_offset);
}

int eve_cmd_exec(int w) {
    eve_write16(REG_CMD_WRITE, _cmd_offset);
    if (w) {
        int r;
        do {
            r = eve_cmd_done();
        } while (!r);
        if (r < 0) return EVE_ERR;
    }
    return EVE_OK;
}

void eve_cmd_burst_start(void) {
	uint32_t addr = EVE_RAM_CMD + _cmd_offset;
    eve_spi_cs_set();
    eve_spi_xchg24(addr | EVE_MEM_WRITE, EVE_SPI_FLAG_TX);
    _cmd_burst = 1;
}

void eve_cmd_burst_end(void) {
    eve_spi_flush();
    eve_spi_cs_clear();
    _cmd_burst = 0;
}

int eve_init(uint32_t *touch_transform) {
	uint8_t chipid = 0;
	uint16_t timeout = 0;

    eve_command(EVE_RST_PULSE, 0);
    eve_command(EVE_CLKEXT, 0);
    eve_command(EVE_ACTIVE, 0);         /* start EVE */

    while (chipid != 0x7C) {            /* if chipid is not 0x7c, continue to read it until it is, EVE needs a moment for it's power on self-test and configuration */
		eve_sleep(1);
		chipid = eve_read8(REG_ID);
		timeout++;
		if (timeout > 400) return EVE_ERR;
	}

    eve_write8(REG_PWM_DUTY, 0);

    /* Initialize Display */
	eve_write16(REG_HCYCLE,  EVE_HCYCLE);   /* total number of clocks per line, incl front/back porch */
	eve_write16(REG_HOFFSET, EVE_HOFFSET);  /* start of active line */
	eve_write16(REG_HSYNC0,  EVE_HSYNC0);   /* start of horizontal sync pulse */
	eve_write16(REG_HSYNC1,  EVE_HSYNC1);   /* end of horizontal sync pulse */
	eve_write16(REG_VCYCLE,  EVE_VCYCLE);   /* total number of lines per screen, including pre/post */
	eve_write16(REG_VOFFSET, EVE_VOFFSET);  /* start of active screen */
	eve_write16(REG_VSYNC0,  EVE_VSYNC0);   /* start of vertical sync pulse */
	eve_write16(REG_VSYNC1,  EVE_VSYNC1);   /* end of vertical sync pulse */
	eve_write8(REG_SWIZZLE,  EVE_SWIZZLE);  /* FT8xx output to LCD - pin order */
	eve_write8(REG_PCLK_POL, EVE_PCLKPOL);  /* LCD data is clocked in on this PCLK edge */
	eve_write8(REG_CSPREAD,	 EVE_CSPREAD);  /* helps with noise, when set to 1 fewer signals are changed simultaneously, reset-default: 1 */
	eve_write16(REG_HSIZE,   EVE_HSIZE);    /* active display width */
	eve_write16(REG_VSIZE,   EVE_VSIZE);    /* active display height */

	/* do not set PCLK yet - wait for just after the first display list */

	/* configure Touch */
	eve_write8(REG_TOUCH_MODE, EVE_TMODE_CONTINUOUS);       /* enable touch */
	eve_write16(REG_TOUCH_RZTHRESH, EVE_TOUCH_RZTHRESH);    /* eliminate any false touches */

	/* disable Audio for now */
	eve_write8(REG_VOL_PB, 0x00);       /* turn recorded audio volume down */
	eve_write8(REG_VOL_SOUND, 0x00);    /* turn synthesizer volume off */
	eve_write16(REG_SOUND, 0x6000);     /* set synthesizer to mute */

	/* write a basic display-list to get things started */
    eve_dl_start(EVE_RAM_DL);
    eve_dl_write(CLEAR_COLOR_RGB(0,0,0));
	eve_dl_write(CLEAR(1,1,1));
    eve_dl_write(DISPLAY());
    eve_dl_swap();

	/* nothing is being displayed yet... the pixel clock is still 0x00 */
	eve_write8(REG_GPIO, 0x80);         /* enable the DISP signal to the LCD panel, it is set to output in REG_GPIO_DIR by default */
	eve_write8(REG_PCLK, EVE_PCLK);     /* now start clocking data to the LCD panel */

    if (touch_transform) {
        eve_write32(REG_TOUCH_TRANSFORM_A, touch_transform[0]);
        eve_write32(REG_TOUCH_TRANSFORM_B, touch_transform[1]);
        eve_write32(REG_TOUCH_TRANSFORM_C, touch_transform[2]);
        eve_write32(REG_TOUCH_TRANSFORM_D, touch_transform[3]);
        eve_write32(REG_TOUCH_TRANSFORM_E, touch_transform[4]);
        eve_write32(REG_TOUCH_TRANSFORM_F, touch_transform[5]);
    } else {
        uint32_t touch_transform[6];
        eve_cmd_dl(CMD_DLSTART);
        eve_cmd_dl(CLEAR_COLOR_RGB(0,0,0));
        eve_cmd_dl(CLEAR(1,1,1));
        eve_cmd(CMD_TEXT, "hhhhs", EVE_HSIZE/2, EVE_VSIZE/2, 27, EVE_OPT_CENTER, "Please tap on the dot.");
        eve_cmd(CMD_CALIBRATE, "w", 0);
        eve_cmd_dl(DISPLAY());
        eve_cmd_dl(CMD_SWAP);
        eve_cmd_exec(1);

        touch_transform[0] = eve_read32(REG_TOUCH_TRANSFORM_A);
        touch_transform[1] = eve_read32(REG_TOUCH_TRANSFORM_B);
        touch_transform[2] = eve_read32(REG_TOUCH_TRANSFORM_C);
        touch_transform[3] = eve_read32(REG_TOUCH_TRANSFORM_D);
        touch_transform[4] = eve_read32(REG_TOUCH_TRANSFORM_E);
        touch_transform[5] = eve_read32(REG_TOUCH_TRANSFORM_F);

        printf("TOUCH TRANSFORM:{0x%x,0x%x,0x%x,0x%x,0x%x,0x%x}\n", touch_transform[0], touch_transform[1], touch_transform[2], touch_transform[3], touch_transform[4], touch_transform[5]);
    }

    eve_write32(REG_CTOUCH_EXTENDED, 0x00);
    eve_cmd(CMD_SETROTATE, "w", 2);
    eve_cmd_exec(1);

    eve_init_touch();
    eve_init_track();
    eve_init_platform();

    eve_sleep(500);
    eve_command(EVE_STANDBY, 0);

    return EVE_OK;
}