/*
Copyright 2016 Fred Sundvik <fsundvik@gmail.com>

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.

You should have received a copy of the GNU General Public License
along with this program.  If not, see <http://www.gnu.org/licenses/>.
*/

#include "gfx.h"

#if GFX_USE_GDISP

#define GDISP_DRIVER_VMT          GDISPVMT_IS31FL3731C_QMK
#define GDISP_SCREEN_HEIGHT       LED_HEIGHT
#define GDISP_SCREEN_WIDTH        LED_WIDTH

#include "gdisp_lld_config.h"
#include "src/gdisp/gdisp_driver.h"

#include "board_is31fl3731c.h"


// Can't include led_tables from here
extern const uint8_t CIE1931_CURVE[];

/*===========================================================================*/
/* Driver local definitions.                                                 */
/*===========================================================================*/

#ifndef GDISP_INITIAL_CONTRAST
    #define GDISP_INITIAL_CONTRAST    0
#endif
#ifndef GDISP_INITIAL_BACKLIGHT
    #define GDISP_INITIAL_BACKLIGHT   0
#endif

#define GDISP_FLG_NEEDFLUSH           (GDISP_FLG_DRIVER<<0)

#define IS31_ADDR_DEFAULT 0x74

#define IS31_REG_CONFIG   0x00
// bits in reg
#define IS31_REG_CONFIG_PICTUREMODE   0x00
#define IS31_REG_CONFIG_AUTOPLAYMODE  0x08
#define IS31_REG_CONFIG_AUDIOPLAYMODE 0x18
// D2:D0 bits are starting frame for autoplay mode

#define IS31_REG_PICTDISP 0x01 // D2:D0 frame select for picture mode

#define IS31_REG_AUTOPLAYCTRL1 0x02
// D6:D4 number of loops (000=infty)
// D2:D0 number of frames to be used

#define IS31_REG_AUTOPLAYCTRL2 0x03 // D5:D0 delay time (*11ms)

#define IS31_REG_DISPLAYOPT 0x05
#define IS31_REG_DISPLAYOPT_INTENSITY_SAME 0x20 // same intensity for all frames
#define IS31_REG_DISPLAYOPT_BLINK_ENABLE 0x8
// D2:D0 bits blink period time (*0.27s)

#define IS31_REG_AUDIOSYNC 0x06
#define IS31_REG_AUDIOSYNC_ENABLE 0x1

#define IS31_REG_FRAMESTATE 0x07

#define IS31_REG_BREATHCTRL1 0x08
// D6:D4 fade out time (26ms*2^i)
// D2:D0 fade in time (26ms*2^i)

#define IS31_REG_BREATHCTRL2 0x09
#define IS31_REG_BREATHCTRL2_ENABLE 0x10
// D2:D0 extinguish time (3.5ms*2^i)

#define IS31_REG_SHUTDOWN 0x0A
#define IS31_REG_SHUTDOWN_OFF 0x0
#define IS31_REG_SHUTDOWN_ON 0x1

#define IS31_REG_AGCCTRL 0x0B
#define IS31_REG_ADCRATE 0x0C

#define IS31_COMMANDREGISTER 0xFD
#define IS31_FUNCTIONREG 0x0B    // helpfully called 'page nine'
#define IS31_FUNCTIONREG_SIZE 0xD

#define IS31_FRAME_SIZE 0xB4

#define IS31_PWM_REG 0x24
#define IS31_PWM_SIZE 0x90

#define IS31_LED_MASK_SIZE 0x12

#define IS31

/*===========================================================================*/
/* Driver local functions.                                                   */
/*===========================================================================*/

typedef struct{
    uint8_t write_buffer_offset;
    uint8_t write_buffer[IS31_FRAME_SIZE];
    uint8_t frame_buffer[GDISP_SCREEN_HEIGHT * GDISP_SCREEN_WIDTH];
    uint8_t page;
}__attribute__((__packed__)) PrivData;

// Some common routines and macros
#define PRIV(g)                         ((PrivData*)g->priv)

/*===========================================================================*/
/* Driver exported functions.                                                */
/*===========================================================================*/

static GFXINLINE void write_page(GDisplay* g, uint8_t page) {
    uint8_t tx[2] __attribute__((aligned(2)));
    tx[0] = IS31_COMMANDREGISTER;
    tx[1] = page;
    write_data(g, tx, 2);
}

static GFXINLINE void write_register(GDisplay* g, uint8_t page, uint8_t reg, uint8_t data) {
    uint8_t tx[2] __attribute__((aligned(2)));
    tx[0] = reg;
    tx[1] = data;
    write_page(g, page);
    write_data(g, tx, 2);
}

static GFXINLINE void write_ram(GDisplay *g, uint8_t page, uint16_t offset, uint16_t length) {
    PRIV(g)->write_buffer_offset = offset;
    write_page(g, page);
    write_data(g, (uint8_t*)PRIV(g), length + 1);
}

LLDSPEC bool_t gdisp_lld_init(GDisplay *g) {
    // The private area is the display surface.
    g->priv = gfxAlloc(sizeof(PrivData));
    __builtin_memset(PRIV(g), 0, sizeof(PrivData));
    PRIV(g)->page = 0;

    // Initialise the board interface
    init_board(g);
    gfxSleepMilliseconds(10);

    // zero function page, all registers (assuming full_page is all zeroes)
    write_ram(g, IS31_FUNCTIONREG, 0, IS31_FUNCTIONREG_SIZE);
    set_hardware_shutdown(g, false);
    gfxSleepMilliseconds(10);
    // software shutdown
    write_register(g, IS31_FUNCTIONREG, IS31_REG_SHUTDOWN, IS31_REG_SHUTDOWN_OFF);
    gfxSleepMilliseconds(10);
    // zero function page, all registers
    write_ram(g, IS31_FUNCTIONREG, 0, IS31_FUNCTIONREG_SIZE);
    gfxSleepMilliseconds(10);


    // zero all LED registers on all 8 pages, and enable the mask
    __builtin_memcpy(PRIV(g)->write_buffer, get_led_mask(g), IS31_LED_MASK_SIZE);
    for(uint8_t i=0; i<8; i++) {
        write_ram(g, i, 0, IS31_FRAME_SIZE);
        gfxSleepMilliseconds(1);
    }

    // software shutdown disable (i.e. turn stuff on)
    write_register(g, IS31_FUNCTIONREG, IS31_REG_SHUTDOWN, IS31_REG_SHUTDOWN_OFF);
    gfxSleepMilliseconds(10);

    // Finish Init
    post_init_board(g);

    /* Initialise the GDISP structure */
    g->g.Width = GDISP_SCREEN_WIDTH;
    g->g.Height = GDISP_SCREEN_HEIGHT;
    g->g.Orientation = GDISP_ROTATE_0;
    g->g.Powermode = powerOff;
    g->g.Backlight = GDISP_INITIAL_BACKLIGHT;
    g->g.Contrast = GDISP_INITIAL_CONTRAST;
    return TRUE;
}

#if GDISP_HARDWARE_FLUSH
    LLDSPEC void gdisp_lld_flush(GDisplay *g) {
        // Don't flush if we don't need it.
        if (!(g->flags & GDISP_FLG_NEEDFLUSH))
            return;

        PRIV(g)->page++;
        PRIV(g)->page %= 2;
        // TODO: some smarter algorithm for this
        // We should run only one physical page at a time
        // This way we don't need to send so much data, and
        // we could use slightly less memory
        uint8_t* src = PRIV(g)->frame_buffer;
        for (int y=0;y<GDISP_SCREEN_HEIGHT;y++) {
            for (int x=0;x<GDISP_SCREEN_WIDTH;x++) {
                uint8_t val = (uint16_t)*src * g->g.Backlight / 100;
                PRIV(g)->write_buffer[get_led_address(g, x, y)]=CIE1931_CURVE[val];
                ++src;
            }
        }
        write_ram(g, PRIV(g)->page, IS31_PWM_REG, IS31_PWM_SIZE);
        gfxSleepMilliseconds(1);
        write_register(g, IS31_FUNCTIONREG, IS31_REG_PICTDISP, PRIV(g)->page);

        g->flags &= ~GDISP_FLG_NEEDFLUSH;
    }
#endif

#if GDISP_HARDWARE_DRAWPIXEL
    LLDSPEC void gdisp_lld_draw_pixel(GDisplay *g) {
        coord_t        x, y;

        switch(g->g.Orientation) {
        default:
        case GDISP_ROTATE_0:
            x = g->p.x;
            y = g->p.y;
            break;
        case GDISP_ROTATE_180:
            x = GDISP_SCREEN_WIDTH-1 - g->p.x;
            y = g->p.y;
            break;
        }
        PRIV(g)->frame_buffer[y * GDISP_SCREEN_WIDTH + x] = gdispColor2Native(g->p.color);
        g->flags |= GDISP_FLG_NEEDFLUSH;
    }
#endif

#if GDISP_HARDWARE_PIXELREAD
    LLDSPEC color_t gdisp_lld_get_pixel_color(GDisplay *g) {
        coord_t        x, y;

        switch(g->g.Orientation) {
        default:
        case GDISP_ROTATE_0:
            x = g->p.x;
            y = g->p.y;
            break;
        case GDISP_ROTATE_180:
            x = GDISP_SCREEN_WIDTH-1 - g->p.x;
            y = g->p.y;
            break;
        }
        return gdispNative2Color(PRIV(g)->frame_buffer[y * GDISP_SCREEN_WIDTH + x]);
    }
#endif

#if GDISP_NEED_CONTROL && GDISP_HARDWARE_CONTROL
    LLDSPEC void gdisp_lld_control(GDisplay *g) {
        switch(g->p.x) {
        case GDISP_CONTROL_POWER:
            if (g->g.Powermode == (powermode_t)g->p.ptr)
                return;
            switch((powermode_t)g->p.ptr) {
            case powerOff:
            case powerSleep:
            case powerDeepSleep:
                write_register(g, IS31_FUNCTIONREG, IS31_REG_SHUTDOWN, IS31_REG_SHUTDOWN_OFF);
                break;
            case powerOn:
                write_register(g, IS31_FUNCTIONREG, IS31_REG_SHUTDOWN, IS31_REG_SHUTDOWN_ON);
                break;
            default:
                return;
            }
            g->g.Powermode = (powermode_t)g->p.ptr;
            return;

        case GDISP_CONTROL_ORIENTATION:
            if (g->g.Orientation == (orientation_t)g->p.ptr)
                return;
            switch((orientation_t)g->p.ptr) {
            /* Rotation is handled by the drawing routines */
            case GDISP_ROTATE_0:
            case GDISP_ROTATE_180:
                g->g.Height = GDISP_SCREEN_HEIGHT;
                g->g.Width = GDISP_SCREEN_WIDTH;
                break;
            case GDISP_ROTATE_90:
            case GDISP_ROTATE_270:
                g->g.Height = GDISP_SCREEN_WIDTH;
                g->g.Width = GDISP_SCREEN_HEIGHT;
                break;
            default:
                return;
            }
            g->g.Orientation = (orientation_t)g->p.ptr;
            return;

        case GDISP_CONTROL_BACKLIGHT:
            if (g->g.Backlight == (unsigned)g->p.ptr)
                return;
            unsigned val = (unsigned)g->p.ptr;
            g->g.Backlight = val > 100 ? 100 : val;
            g->flags |= GDISP_FLG_NEEDFLUSH;
            return;
        }
    }
#endif // GDISP_NEED_CONTROL

#endif // GFX_USE_GDISP
