// Copyright 2015-2021 Espressif Systems (Shanghai) PTE LTD
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at

//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

#include <stdint.h>
#include <stdlib.h>
#include <string.h>
#include "freertos/FreeRTOS.h"
#include "freertos/task.h"
#include "sccb.h"
#include "gc0308.h"
#include "gc0308_regs.h"
#include "gc0308_settings.h"

#if defined(ARDUINO_ARCH_ESP32) && defined(CONFIG_ARDUHAL_ESP_LOG)
#include "esp32-hal-log.h"
#else
#include "esp_log.h"
static const char *TAG = "gc0308";
#endif

#define H8(v) ((v)>>8)
#define L8(v) ((v)&0xff)

//#define REG_DEBUG_ON

static int read_reg(uint8_t slv_addr, const uint16_t reg)
{
    int ret = SCCB_Read(slv_addr, reg);
#ifdef REG_DEBUG_ON
    if (ret < 0) {
        ESP_LOGE(TAG, "READ REG 0x%04x FAILED: %d", reg, ret);
    }
#endif
    return ret;
}

static int write_reg(uint8_t slv_addr, const uint16_t reg, uint8_t value)
{
    int ret = 0;
#ifndef REG_DEBUG_ON
    ret = SCCB_Write(slv_addr, reg, value);
#else
    int old_value = read_reg(slv_addr, reg);
    if (old_value < 0) {
        return old_value;
    }
    if ((uint8_t)old_value != value) {
        ESP_LOGI(TAG, "NEW REG 0x%04x: 0x%02x to 0x%02x", reg, (uint8_t)old_value, value);
        ret = SCCB_Write(slv_addr, reg, value);
    } else {
        ESP_LOGD(TAG, "OLD REG 0x%04x: 0x%02x", reg, (uint8_t)old_value);
        ret = SCCB_Write(slv_addr, reg, value);//maybe not?
    }
    if (ret < 0) {
        ESP_LOGE(TAG, "WRITE REG 0x%04x FAILED: %d", reg, ret);
    }
#endif
    return ret;
}

static int check_reg_mask(uint8_t slv_addr, uint16_t reg, uint8_t mask)
{
    return (read_reg(slv_addr, reg) & mask) == mask;
}

static int set_reg_bits(uint8_t slv_addr, uint16_t reg, uint8_t offset, uint8_t mask, uint8_t value)
{
    int ret = 0;
    uint8_t c_value, new_value;
    ret = read_reg(slv_addr, reg);
    if (ret < 0) {
        return ret;
    }
    c_value = ret;
    new_value = (c_value & ~(mask << offset)) | ((value & mask) << offset);
    ret = write_reg(slv_addr, reg, new_value);
    return ret;
}

static int write_regs(uint8_t slv_addr, const uint8_t (*regs)[2], size_t regs_size)
{
    int i = 0, ret = 0;
    while (!ret && (i < regs_size)) {
        if (regs[i][0] == REG_DLY) {
            vTaskDelay(regs[i][1] / portTICK_PERIOD_MS);
        } else {
            ret = write_reg(slv_addr, regs[i][0], regs[i][1]);
        }
        i++;
    }
    return ret;
}

static void print_regs(uint8_t slv_addr)
{
#ifdef DEBUG_PRINT_REG
    ESP_LOGI(TAG, "REG list look ======================");
    for (size_t i = 0xf0; i <= 0xfe; i++) {
        ESP_LOGI(TAG, "reg[0x%02x] = 0x%02x", i, read_reg(slv_addr, i));
    }
    ESP_LOGI(TAG, "\npage 0 ===");
    write_reg(slv_addr, 0xfe, 0x00); // page 0
    for (size_t i = 0x03; i <= 0xa2; i++) {
        ESP_LOGI(TAG, "p0 reg[0x%02x] = 0x%02x", i, read_reg(slv_addr, i));
    }

    ESP_LOGI(TAG, "\npage 3 ===");
    write_reg(slv_addr, 0xfe, 0x03); // page 3
    for (size_t i = 0x01; i <= 0x43; i++) {
        ESP_LOGI(TAG, "p3 reg[0x%02x] = 0x%02x", i, read_reg(slv_addr, i));
    }
#endif
}

static int reset(sensor_t *sensor)
{
    int ret = 0;
    // Software Reset: clear all registers and reset them to their default values
    ret = write_reg(sensor->slv_addr, RESET_RELATED, 0xf0);
    if (ret) {
        ESP_LOGE(TAG, "Software Reset FAILED!");
        return ret;
    }

    vTaskDelay(80 / portTICK_PERIOD_MS);
    ret = write_regs(sensor->slv_addr, gc0308_sensor_default_regs, sizeof(gc0308_sensor_default_regs)/(sizeof(uint8_t) * 2));
    if (ret == 0) {
        ESP_LOGD(TAG, "Camera defaults loaded");
        vTaskDelay(80 / portTICK_PERIOD_MS);
        write_reg(sensor->slv_addr, 0xfe, 0x00);
#ifdef CONFIG_IDF_TARGET_ESP32
        set_reg_bits(sensor->slv_addr, 0x28, 4, 0x07, 1);  //frequency division for esp32, ensure pclk <= 15MHz
#endif
    }
    return ret;
}

static int set_pixformat(sensor_t *sensor, pixformat_t pixformat)
{
    int ret = 0;

    switch (pixformat) {
    case PIXFORMAT_RGB565:
        write_reg(sensor->slv_addr, 0xfe, 0x00);
        ret = set_reg_bits(sensor->slv_addr, 0x24, 0, 0x0f, 6);  //RGB565
        break;

    case PIXFORMAT_YUV422:
        write_reg(sensor->slv_addr, 0xfe, 0x00);
        ret = set_reg_bits(sensor->slv_addr, 0x24, 0, 0x0f, 2); //yuv422 Y Cb Y Cr
        break;
    case PIXFORMAT_GRAYSCALE:
        write_reg(sensor->slv_addr, 0xfe, 0x00);
        ret = write_reg(sensor->slv_addr, 0x24, 0xb1);
        break;
    default:
        ESP_LOGW(TAG, "unsupport format");
        ret = -1;
        break;
    }

    if (ret == 0) {
        sensor->pixformat = pixformat;
        ESP_LOGD(TAG, "Set pixformat to: %u", pixformat);
    }
    return ret;
}

static int set_framesize(sensor_t *sensor, framesize_t framesize)
{
    int ret = 0;
    if (framesize > FRAMESIZE_VGA) {
        ESP_LOGW(TAG, "Invalid framesize: %u", framesize);
        framesize = FRAMESIZE_VGA;
    }
    sensor->status.framesize = framesize;
    uint16_t w = resolution[framesize].width;
    uint16_t h = resolution[framesize].height;
    uint16_t row_s = (resolution[FRAMESIZE_VGA].height - h) / 2;
    uint16_t col_s = (resolution[FRAMESIZE_VGA].width - w) / 2;
    (void)row_s;
    (void)col_s;

#if CONFIG_GC_SENSOR_SUBSAMPLE_MODE
    struct subsample_cfg {
        uint16_t ratio_numerator;
        uint16_t ratio_denominator;
        uint8_t reg0x54;
        uint8_t reg0x56;
        uint8_t reg0x57;
        uint8_t reg0x58;
        uint8_t reg0x59;
    };
    const struct subsample_cfg subsample_cfgs[] = { // define some subsample ratio
        {84, 420, 0x55, 0x00, 0x00, 0x00, 0x00}, //1/5
        {105, 420, 0x44, 0x00, 0x00, 0x00, 0x00},//1/4
        {140, 420, 0x33, 0x00, 0x00, 0x00, 0x00},//1/3
        {210, 420, 0x22, 0x00, 0x00, 0x00, 0x00},//1/2
        {240, 420, 0x77, 0x02, 0x46, 0x02, 0x46},//4/7
        {252, 420, 0x55, 0x02, 0x04, 0x02, 0x04},//3/5
        {280, 420, 0x33, 0x02, 0x00, 0x02, 0x00},//2/3
        {420, 420, 0x11, 0x00, 0x00, 0x00, 0x00},//1/1
    };
    uint16_t win_w = 640;
    uint16_t win_h = 480;
    const struct subsample_cfg *cfg = NULL;
    /**
     * Strategy: try to keep the maximum perspective
     */
    for (size_t i = 0; i < sizeof(subsample_cfgs) / sizeof(struct subsample_cfg); i++) {
        cfg = &subsample_cfgs[i];
        if ((win_w * cfg->ratio_numerator / cfg->ratio_denominator >= w) && (win_h * cfg->ratio_numerator / cfg->ratio_denominator >= h)) {
            win_w = w * cfg->ratio_denominator / cfg->ratio_numerator;
            win_h = h * cfg->ratio_denominator / cfg->ratio_numerator;
            row_s = (resolution[FRAMESIZE_VGA].height - win_h) / 2;
            col_s = (resolution[FRAMESIZE_VGA].width - win_w) / 2;
            ESP_LOGI(TAG, "subsample win:%dx%d, ratio:%f", win_w, win_h, (float)cfg->ratio_numerator / (float)cfg->ratio_denominator);
            break;
        }
    }

    write_reg(sensor->slv_addr, 0xfe, 0x00);

    write_reg(sensor->slv_addr, 0x05, H8(row_s));
    write_reg(sensor->slv_addr, 0x06, L8(row_s));
    write_reg(sensor->slv_addr, 0x07, H8(col_s));
    write_reg(sensor->slv_addr, 0x08, L8(col_s));
    write_reg(sensor->slv_addr, 0x09, H8(win_h + 8));
    write_reg(sensor->slv_addr, 0x0a, L8(win_h + 8));
    write_reg(sensor->slv_addr, 0x0b, H8(win_w + 8));
    write_reg(sensor->slv_addr, 0x0c, L8(win_w + 8));

    write_reg(sensor->slv_addr, 0xfe, 0x01);
    set_reg_bits(sensor->slv_addr, 0x53, 7, 0x01, 1);
    set_reg_bits(sensor->slv_addr, 0x55, 0, 0x01, 1);
    write_reg(sensor->slv_addr, 0x54, cfg->reg0x54);
    write_reg(sensor->slv_addr, 0x56, cfg->reg0x56);
    write_reg(sensor->slv_addr, 0x57, cfg->reg0x57);
    write_reg(sensor->slv_addr, 0x58, cfg->reg0x58);
    write_reg(sensor->slv_addr, 0x59, cfg->reg0x59);

    write_reg(sensor->slv_addr, 0xfe, 0x00);

#elif CONFIG_GC_SENSOR_WINDOWING_MODE
    write_reg(sensor->slv_addr, 0xfe, 0x00);

    write_reg(sensor->slv_addr, 0xf7, col_s / 4);
    write_reg(sensor->slv_addr, 0xf8, row_s / 4);
    write_reg(sensor->slv_addr, 0xf9, (col_s + w) / 4);
    write_reg(sensor->slv_addr, 0xfa, (row_s + h) / 4);

    write_reg(sensor->slv_addr, 0x05, H8(row_s));
    write_reg(sensor->slv_addr, 0x06, L8(row_s));
    write_reg(sensor->slv_addr, 0x07, H8(col_s));
    write_reg(sensor->slv_addr, 0x08, L8(col_s));

    write_reg(sensor->slv_addr, 0x09, H8(h + 8));
    write_reg(sensor->slv_addr, 0x0a, L8(h + 8));
    write_reg(sensor->slv_addr, 0x0b, H8(w + 8));
    write_reg(sensor->slv_addr, 0x0c, L8(w + 8));

#endif
    if (ret == 0) {
        ESP_LOGD(TAG, "Set framesize to: %ux%u", w, h);
    }
    return 0;
}

static int set_contrast(sensor_t *sensor, int contrast)
{
    if (contrast > 0) {
        sensor->status.contrast = contrast;
        write_reg(sensor->slv_addr, 0xfe, 0x00);
        write_reg(sensor->slv_addr, 0xb3, contrast);
    }
    return 0;
}

static int set_global_gain(sensor_t *sensor, int gain_level)
{
    if (gain_level != 0) {
        write_reg(sensor->slv_addr, 0xfe, 0x00);
        write_reg(sensor->slv_addr, 0x50, gain_level);
    }
    return 0;
}

static int set_hmirror(sensor_t *sensor, int enable)
{
    int ret = 0;
    sensor->status.hmirror = enable;
    ret = write_reg(sensor->slv_addr, 0xfe, 0x00);
    ret |= set_reg_bits(sensor->slv_addr, 0x14, 0, 0x01, enable != 0);
    if (ret == 0) {
        ESP_LOGD(TAG, "Set h-mirror to: %d", enable);
    }
    return ret;
}

static int set_vflip(sensor_t *sensor, int enable)
{
    int ret = 0;
    sensor->status.vflip = enable;
    ret = write_reg(sensor->slv_addr, 0xfe, 0x00);
    ret |= set_reg_bits(sensor->slv_addr, 0x14, 1, 0x01, enable != 0);
    if (ret == 0) {
        ESP_LOGD(TAG, "Set v-flip to: %d", enable);
    }
    return ret;
}

static int set_colorbar(sensor_t *sensor, int enable)
{
    int ret = 0;
    ret = write_reg(sensor->slv_addr, 0xfe, 0x00);
    ret |= set_reg_bits(sensor->slv_addr, 0x2e, 0, 0x01, enable);
    if (ret == 0) {
        sensor->status.colorbar = enable;
        ESP_LOGD(TAG, "Set colorbar to: %d", enable);
    }
    return ret;
}

static int get_reg(sensor_t *sensor, int reg, int mask)
{
    int ret = 0;
    if (mask > 0xFF) {
        ESP_LOGE(TAG, "mask should not more than 0xff");
    } else {
        ret = read_reg(sensor->slv_addr, reg);
    }
    if (ret > 0) {
        ret &= mask;
    }
    return ret;
}

static int set_reg(sensor_t *sensor, int reg, int mask, int value)
{
    int ret = 0;
    if (mask > 0xFF) {
        ESP_LOGE(TAG, "mask should not more than 0xff");
    } else {
        ret = read_reg(sensor->slv_addr, reg);
    }
    if (ret < 0) {
        return ret;
    }
    value = (ret & ~mask) | (value & mask);

    if (mask > 0xFF) {

    } else {
        ret = write_reg(sensor->slv_addr, reg, value);
    }
    return ret;
}

static int init_status(sensor_t *sensor)
{
    write_reg(sensor->slv_addr, 0xfe, 0x00);
    sensor->status.brightness = 0;
    sensor->status.contrast = 50;
    sensor->status.saturation = 0;
    sensor->status.sharpness = 0;
    sensor->status.denoise = 0;
    sensor->status.ae_level = 0;
    sensor->status.gainceiling = 0;
    sensor->status.awb = 0;
    sensor->status.dcw = 0;
    sensor->status.agc = 0;
    sensor->status.aec = 0;
    sensor->status.hmirror = check_reg_mask(sensor->slv_addr, 0x14, 0x01);
    sensor->status.vflip = check_reg_mask(sensor->slv_addr, 0x14, 0x02);
    sensor->status.colorbar = 0;
    sensor->status.bpc = 0;
    sensor->status.wpc = 0;
    sensor->status.raw_gma = 0;
    sensor->status.lenc = 0;
    sensor->status.quality = 0;
    sensor->status.special_effect = 0;
    sensor->status.wb_mode = 0;
    sensor->status.awb_gain = 0;
    sensor->status.agc_gain = 0;
    sensor->status.aec_value = 0;
    sensor->status.aec2 = 0;

    print_regs(sensor->slv_addr);
    return 0;
}

static int set_dummy(sensor_t *sensor, int val)
{
    ESP_LOGW(TAG, "Unsupported");
    return -1;
}
static int set_gainceiling_dummy(sensor_t *sensor, gainceiling_t val)
{
    ESP_LOGW(TAG, "Unsupported");
    return -1;
}

int gc0308_detect(int slv_addr, sensor_id_t *id)
{
    if (GC0308_SCCB_ADDR == slv_addr) {
        write_reg(slv_addr, 0xfe, 0x00);
        uint8_t PID = SCCB_Read(slv_addr, 0x00);
        if (GC0308_PID == PID) {
            id->PID = PID;
            return PID;
        } else {
            ESP_LOGI(TAG, "Mismatch PID=0x%x", PID);
        }
    }
    return 0;
}

int gc0308_init(sensor_t *sensor)
{
    sensor->init_status = init_status;
    sensor->reset = reset;
    sensor->set_pixformat = set_pixformat;
    sensor->set_framesize = set_framesize;
    sensor->set_contrast = set_contrast;
    sensor->set_brightness = set_dummy;
    sensor->set_saturation = set_dummy;
    sensor->set_sharpness = set_dummy;
    sensor->set_denoise = set_dummy;
    sensor->set_gainceiling = set_gainceiling_dummy;
    sensor->set_quality = set_dummy;
    sensor->set_colorbar = set_colorbar;
    sensor->set_whitebal = set_dummy;
    sensor->set_gain_ctrl = set_global_gain;
    sensor->set_exposure_ctrl = set_dummy;
    sensor->set_hmirror = set_hmirror;
    sensor->set_vflip = set_vflip;

    sensor->set_aec2 = set_dummy;
    sensor->set_awb_gain = set_dummy;
    sensor->set_agc_gain = set_dummy;
    sensor->set_aec_value = set_dummy;

    sensor->set_special_effect = set_dummy;
    sensor->set_wb_mode = set_dummy;
    sensor->set_ae_level = set_dummy;

    sensor->set_dcw = set_dummy;
    sensor->set_bpc = set_dummy;
    sensor->set_wpc = set_dummy;

    sensor->set_raw_gma = set_dummy;
    sensor->set_lenc = set_dummy;

    sensor->get_reg = get_reg;
    sensor->set_reg = set_reg;
    sensor->set_res_raw = NULL;
    sensor->set_pll = NULL;
    sensor->set_xclk = NULL;

    ESP_LOGD(TAG, "GC0308 Attached");
    return 0;
}