/*
 * This file is part of the Circuit Python project, https://github.com/adafruit/circuitpython
 *
 * The MIT License (MIT)
 *
 * Copyright (c) 2018 Roy Hooper
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */


#include "py/obj.h"
#include "py/objstr.h"
#include "py/objtype.h"
#include "py/runtime.h"
#include "shared-bindings/_pixelbuf/PixelBuf.h"
#include <string.h>

// Helper to ensure we have the native super class instead of a subclass.
static pixelbuf_pixelbuf_obj_t* native_pixelbuf(mp_obj_t pixelbuf_obj) {
 mp_obj_t native_pixelbuf = mp_instance_cast_to_native_base(pixelbuf_obj, &pixelbuf_pixelbuf_type);
 mp_obj_assert_native_inited(native_pixelbuf);
 return MP_OBJ_TO_PTR(native_pixelbuf);
}

void common_hal__pixelbuf_pixelbuf_construct(pixelbuf_pixelbuf_obj_t *self, size_t n,
 pixelbuf_byteorder_details_t* byteorder, mp_float_t brightness, bool auto_write,
 uint8_t* header, size_t header_len, uint8_t* trailer, size_t trailer_len) {

 self->pixel_count = n;
 self->byteorder = *byteorder; // Copied because we modify for dotstar
 self->bytes_per_pixel = byteorder->is_dotstar ? 4 : byteorder->bpp;
 self->auto_write = false;

 size_t pixel_len = self->pixel_count * self->bytes_per_pixel;
 self->transmit_buffer_obj = mp_obj_new_bytes_of_zeros(header_len + pixel_len + trailer_len);
 mp_obj_str_t *o = MP_OBJ_TO_PTR(self->transmit_buffer_obj);

 // Abuse the bytes object a bit by mutating it's data by dropping the const. If the user's
 // Python code holds onto it, they'll find out that it changes. At least this way it isn't
 // mutable by the code itself.
 uint8_t* transmit_buffer = (uint8_t*) o->data;
 memcpy(transmit_buffer, header, header_len);
 memcpy(transmit_buffer + header_len + pixel_len, trailer, trailer_len);
 self->post_brightness_buffer = transmit_buffer + header_len;

 if (self->byteorder.is_dotstar) {
 // Initialize the buffer with the dotstar start bytes.
 // Note: Header and end must be setup by caller
 for (uint i = 0; i < self->pixel_count * 4; i += 4) {
 self->post_brightness_buffer[i] = DOTSTAR_LED_START_FULL_BRIGHT;
 }
 }
 // Call set_brightness so that it can allocate a second buffer if needed.
 self->brightness = 1.0;
 common_hal__pixelbuf_pixelbuf_set_brightness(MP_OBJ_FROM_PTR(self), brightness);

 // Turn on auto_write. We don't want to do it with the above brightness call.
 self->auto_write = auto_write;
}

size_t common_hal__pixelbuf_pixelbuf_get_len(mp_obj_t self_in) {
 pixelbuf_pixelbuf_obj_t* self = native_pixelbuf(self_in);
 return self->pixel_count;
}

uint8_t common_hal__pixelbuf_pixelbuf_get_bpp(mp_obj_t self_in) {
 pixelbuf_pixelbuf_obj_t* self = native_pixelbuf(self_in);
 return self->byteorder.bpp;
}

mp_obj_t common_hal__pixelbuf_pixelbuf_get_byteorder_string(mp_obj_t self_in) {
 pixelbuf_pixelbuf_obj_t* self = native_pixelbuf(self_in);
 return self->byteorder.order_string;
}

bool common_hal__pixelbuf_pixelbuf_get_auto_write(mp_obj_t self_in) {
 pixelbuf_pixelbuf_obj_t* self = native_pixelbuf(self_in);
 return self->auto_write;
}

void common_hal__pixelbuf_pixelbuf_set_auto_write(mp_obj_t self_in, bool auto_write) {
 pixelbuf_pixelbuf_obj_t* self = native_pixelbuf(self_in);
 self->auto_write = auto_write;
}

mp_float_t common_hal__pixelbuf_pixelbuf_get_brightness(mp_obj_t self_in) {
 pixelbuf_pixelbuf_obj_t* self = native_pixelbuf(self_in);
 return self->brightness;
}

void common_hal__pixelbuf_pixelbuf_set_brightness(mp_obj_t self_in, mp_float_t brightness) {
 pixelbuf_pixelbuf_obj_t* self = native_pixelbuf(self_in);
 // Skip out if the brightness is already set. The default of self->brightness is 1.0. So, this
 // also prevents the pre_brightness_buffer allocation when brightness is set to 1.0 again.
 mp_float_t change = brightness - self->brightness;
 if (-0.001 < change && change < 0.001) {
 return;
 }
 self->brightness = brightness;
 size_t pixel_len = self->pixel_count * self->bytes_per_pixel;
 if (self->pre_brightness_buffer == NULL) {
 self->pre_brightness_buffer = m_malloc(pixel_len, false);
 memcpy(self->pre_brightness_buffer, self->post_brightness_buffer, pixel_len);
 }
 for (size_t i = 0; i < pixel_len; i++) {
 // Don't adjust per-pixel luminance bytes in dotstar mode
 if (self->byteorder.is_dotstar && i % 4 == 0) {
 continue;
 }
 self->post_brightness_buffer[i] = self->pre_brightness_buffer[i] * self->brightness;
 }

 if (self->auto_write) {
 common_hal__pixelbuf_pixelbuf_show(self_in);
 }
}

void _pixelbuf_parse_color(pixelbuf_pixelbuf_obj_t* self, mp_obj_t color, uint8_t* r, uint8_t* g, uint8_t* b, uint8_t* w) {
 pixelbuf_byteorder_details_t *byteorder = &self->byteorder;
 // w is shared between white in NeoPixels and brightness in dotstars (so that DotStars can have
 // per-pixel brightness). Set the defaults here in case it isn't set below.
 if (byteorder->is_dotstar) {
 *w = 255;
 } else {
 *w = 0;
 }

 if (MP_OBJ_IS_INT(color)) {
 mp_int_t value = mp_obj_get_int_truncated(color);
 *r = value >> 16 & 0xff;
 *g = (value >> 8) & 0xff;
 *b = value & 0xff;
 } else {
 mp_obj_t *items;
 size_t len;
 mp_obj_get_array(color, &len, &items);
 if (len < 3 || len > 4) {
 mp_raise_ValueError_varg(translate("Expected tuple of length %d, got %d"), byteorder->bpp, len);
 }

 *r = mp_obj_get_int_truncated(items[PIXEL_R]);
 *g = mp_obj_get_int_truncated(items[PIXEL_G]);
 *b = mp_obj_get_int_truncated(items[PIXEL_B]);
 if (len > 3) {
 if (mp_obj_is_float(items[PIXEL_W])) {
 *w = 255 * mp_obj_get_float(items[PIXEL_W]);
 } else {
 *w = mp_obj_get_int_truncated(items[PIXEL_W]);
 }
 return;
 }
 }
 // Int colors can't set white directly so convert to white when all components are equal.
 // Also handles RGBW values assigned an RGB tuple.
 if (!byteorder->is_dotstar && byteorder->bpp == 4 && byteorder->has_white && *r == *g && *r == *b) {
 *w = *r;
 *r = 0;
 *g = 0;
 *b = 0;
 }
}

void _pixelbuf_set_pixel_color(pixelbuf_pixelbuf_obj_t* self, size_t index, uint8_t r, uint8_t g, uint8_t b, uint8_t w) {
 // DotStars don't have white, instead they have 5 bit brightness so pack it into w. Shift right
 // by three to leave the top five bits.
 if (self->bytes_per_pixel == 4 && self->byteorder.is_dotstar) {
 w = DOTSTAR_LED_START | w >> 3;
 }
 pixelbuf_rgbw_t *rgbw_order = &self->byteorder.byteorder;
 size_t offset = index * self->bytes_per_pixel;
 if (self->pre_brightness_buffer != NULL) {
 uint8_t* pre_brightness_buffer = self->pre_brightness_buffer + offset;
 if (self->bytes_per_pixel == 4) {
 pre_brightness_buffer[rgbw_order->w] = w;
 }

 pre_brightness_buffer[rgbw_order->r] = r;
 pre_brightness_buffer[rgbw_order->g] = g;
 pre_brightness_buffer[rgbw_order->b] = b;
 }

 uint8_t* post_brightness_buffer = self->post_brightness_buffer + offset;
 if (self->bytes_per_pixel == 4) {
 // Only apply brightness if w is actually white (aka not DotStar.)
 if (!self->byteorder.is_dotstar) {
 w *= self->brightness;
 }
 post_brightness_buffer[rgbw_order->w] = w;
 }
 post_brightness_buffer[rgbw_order->r] = r * self->brightness;
 post_brightness_buffer[rgbw_order->g] = g * self->brightness;
 post_brightness_buffer[rgbw_order->b] = b * self->brightness;
}

void _pixelbuf_set_pixel(pixelbuf_pixelbuf_obj_t* self, size_t index, mp_obj_t value) {
 uint8_t r;
 uint8_t g;
 uint8_t b;
 uint8_t w;
 _pixelbuf_parse_color(self, value, &r, &g, &b, &w);
 _pixelbuf_set_pixel_color(self, index, r, g, b, w);
}

void common_hal__pixelbuf_pixelbuf_set_pixels(mp_obj_t self_in, size_t start, mp_int_t step, size_t slice_len, mp_obj_t* values) {
 pixelbuf_pixelbuf_obj_t* self = native_pixelbuf(self_in);
 for (size_t i = 0; i < slice_len; i++) {
 _pixelbuf_set_pixel(self, start, values[i]);
 start+=step;
 }
 if (self->auto_write) {
 common_hal__pixelbuf_pixelbuf_show(self_in);
 }
}

void common_hal__pixelbuf_pixelbuf_set_pixel(mp_obj_t self_in, size_t index, mp_obj_t value) {
 pixelbuf_pixelbuf_obj_t* self = native_pixelbuf(self_in);
 _pixelbuf_set_pixel(self, index, value);
 if (self->auto_write) {
 common_hal__pixelbuf_pixelbuf_show(self_in);
 }
}

mp_obj_t common_hal__pixelbuf_pixelbuf_get_pixel(mp_obj_t self_in, size_t index) {
 pixelbuf_pixelbuf_obj_t* self = native_pixelbuf(self_in);
 mp_obj_t elems[self->byteorder.bpp];
 uint8_t* pixel_buffer = self->post_brightness_buffer;
 if (self->pre_brightness_buffer != NULL) {
 pixel_buffer = self->pre_brightness_buffer;
 }
 pixel_buffer += self->byteorder.bpp * index;

 pixelbuf_rgbw_t *rgbw_order = &self->byteorder.byteorder;
 elems[0] = MP_OBJ_NEW_SMALL_INT(pixel_buffer[rgbw_order->r]);
 elems[1] = MP_OBJ_NEW_SMALL_INT(pixel_buffer[rgbw_order->g]);
 elems[2] = MP_OBJ_NEW_SMALL_INT(pixel_buffer[rgbw_order->b]);
 if (self->byteorder.bpp > 3) {
 uint8_t w = pixel_buffer[rgbw_order->w];
 if (self->byteorder.is_dotstar) {
 elems[3] = mp_obj_new_float((w & 0b00011111) / 31.0);
 } else {
 elems[3] = MP_OBJ_NEW_SMALL_INT(w);
 }
 }

 return mp_obj_new_tuple(self->byteorder.bpp, elems);
}

void common_hal__pixelbuf_pixelbuf_show(mp_obj_t self_in) {
 pixelbuf_pixelbuf_obj_t* self = native_pixelbuf(self_in);
 mp_obj_t dest[2 + 1];
 mp_load_method(self_in, MP_QSTR__transmit, dest);

 dest[2] = self->transmit_buffer_obj;

 mp_call_method_n_kw(1, 0, dest);
}

void common_hal__pixelbuf_pixelbuf_fill(mp_obj_t self_in, mp_obj_t fill_color) {
 pixelbuf_pixelbuf_obj_t* self = native_pixelbuf(self_in);

 uint8_t r;
 uint8_t g;
 uint8_t b;
 uint8_t w;
 _pixelbuf_parse_color(self, fill_color, &r, &g, &b, &w);

 for (size_t i = 0; i < self->pixel_count; i++) {
 _pixelbuf_set_pixel_color(self, i, r, g, b, w);
 }
 if (self->auto_write) {
 common_hal__pixelbuf_pixelbuf_show(self_in);
 }
}