#include "touch.h"
#include "pins.h"

#include <Arduino.h>

#if defined(CYD_BOARD_3248S035)
#include <Wire.h>
#endif

/**
 * 2.8": dedicated SoftSPI + BL/TR diagonal fix.
 * 3.5C (3248S035C): capacitive GT911 on I2C SDA33/SCL32/INT21/RST25.
 */

int16_t g_dbg_phys_x = -1;
int16_t g_dbg_phys_y = -1;
int16_t g_dbg_logic_x = -1;
int16_t g_dbg_logic_y = -1;
bool g_dbg_touch_down = false;

static int16_t clampi(int32_t v, int32_t lo, int32_t hi) {
  if (v < lo) {
    return (int16_t)lo;
  }
  if (v > hi) {
    return (int16_t)hi;
  }
  return (int16_t)v;
}

#if defined(CYD_BOARD_3248S035)

/* Minimal GT911 — no config rewrite (TAMC setResolution can hang Wire). */
static uint8_t s_gt_addr = 0x5D;
static constexpr uint16_t GT_POINT_INFO = 0x814E;
static constexpr uint16_t GT_POINT_1 = 0x814F;

static bool gt_write8(uint16_t reg, uint8_t val) {
  Wire.beginTransmission(s_gt_addr);
  Wire.write((uint8_t)(reg >> 8));
  Wire.write((uint8_t)(reg & 0xFF));
  Wire.write(val);
  return Wire.endTransmission() == 0;
}

static bool gt_read(uint16_t reg, uint8_t *buf, uint8_t len) {
  Wire.beginTransmission(s_gt_addr);
  Wire.write((uint8_t)(reg >> 8));
  Wire.write((uint8_t)(reg & 0xFF));
  if (Wire.endTransmission(false) != 0) {
    return false;
  }
  const uint8_t n = Wire.requestFrom(s_gt_addr, len);
  if (n != len) {
    return false;
  }
  for (uint8_t i = 0; i < len; i++) {
    buf[i] = Wire.read();
  }
  return true;
}

static bool gt_probe(uint8_t addr) {
  Wire.beginTransmission(addr);
  return Wire.endTransmission() == 0;
}

/* TAMC-compatible address select: INT low => 0x5D, INT high => 0x14 */
static void gt_hw_reset(bool addr_0x14) {
  pinMode(CYD_GT911_INT, OUTPUT);
  pinMode(CYD_GT911_RST, OUTPUT);
  digitalWrite(CYD_GT911_INT, LOW);
  digitalWrite(CYD_GT911_RST, LOW);
  delay(10);
  digitalWrite(CYD_GT911_INT, addr_0x14 ? HIGH : LOW);
  delay(1);
  digitalWrite(CYD_GT911_RST, HIGH);
  delay(5);
  digitalWrite(CYD_GT911_INT, LOW);
  delay(50);
  /* Backlight is GPIO27 — leave INT as input for polling / optional IRQ. */
  pinMode(CYD_GT911_INT, INPUT);
  delay(50);
}

static bool gt_find_addr() {
  for (uint8_t a : {uint8_t(0x5D), uint8_t(0x14)}) {
    if (gt_probe(a)) {
      s_gt_addr = a;
      return true;
    }
  }
  return false;
}

void touch_init() {
  Serial.println("Touch: GT911 I2C capacitive (3.5C) minimal");
  Wire.begin(CYD_GT911_SDA, CYD_GT911_SCL);
  Wire.setClock(100000);
#if defined(WIRE_HAS_TIMEOUT) || defined(ESP32)
  Wire.setTimeOut(50);
#endif

  if (!gt_find_addr()) {
    Serial.println("GT911 not found — hw reset 0x5D");
    gt_hw_reset(false);
    if (!gt_find_addr()) {
      Serial.println("GT911 not found — hw reset 0x14");
      gt_hw_reset(true);
      gt_find_addr();
    }
  }

  Serial.printf("GT911 probe 0x5D=%s 0x14=%s using=0x%02X\n",
                gt_probe(0x5D) ? "OK" : "no", gt_probe(0x14) ? "OK" : "no",
                s_gt_addr);
  Serial.printf("GT911 SDA=%d SCL=%d INT=%d RST=%d\n", CYD_GT911_SDA,
                CYD_GT911_SCL, CYD_GT911_INT, CYD_GT911_RST);
}

void touch_read_cb(lv_indev_t * /*indev*/, lv_indev_data_t *data) {
  uint8_t info = 0;
  static uint32_t last_log = 0;
  const bool do_log = (millis() - last_log > 200);

  if (!gt_read(GT_POINT_INFO, &info, 1)) {
    data->state = LV_INDEV_STATE_RELEASED;
    g_dbg_touch_down = false;
    if (do_log) {
      last_log = millis();
      Serial.println("TouchProbe GT911 I2C err");
    }
    return;
  }

  const uint8_t touches = info & 0x0F;
  const bool buffered = (info & 0x80) != 0;

  if (!buffered || touches == 0) {
    if (buffered) {
      gt_write8(GT_POINT_INFO, 0);
    }
    data->state = LV_INDEV_STATE_RELEASED;
    g_dbg_touch_down = false;
    return;
  }

  uint8_t pt[7];
  if (!gt_read(GT_POINT_1, pt, 7)) {
    gt_write8(GT_POINT_INFO, 0);
    data->state = LV_INDEV_STATE_RELEASED;
    g_dbg_touch_down = false;
    return;
  }
  gt_write8(GT_POINT_INFO, 0);

  const int16_t raw_x = (int16_t)(pt[1] | (pt[2] << 8));
  const int16_t raw_y = (int16_t)(pt[3] | (pt[4] << 8));

  /* Native 320x480 → LVGL 270. Mirror long axis so L/R matches UI
   * (else preset 3 hits 10). Resulting UI ≈ (H-1-raw_y, raw_x). */
  const int16_t nx = clampi(raw_x, 0, SCREEN_WIDTH - 1);
  const int16_t ny = clampi(raw_y, 0, SCREEN_HEIGHT - 1);
  const int16_t feed_x = (int16_t)((SCREEN_WIDTH - 1) - nx);
  const int16_t feed_y = (int16_t)((SCREEN_HEIGHT - 1) - ny);
  const int16_t ui_x = (int16_t)((SCREEN_HEIGHT - 1) - ny);
  const int16_t ui_y = nx;

  g_dbg_phys_x = raw_x;
  g_dbg_phys_y = raw_y;
  g_dbg_logic_x = ui_x;
  g_dbg_logic_y = ui_y;
  g_dbg_touch_down = true;

  if (do_log) {
    last_log = millis();
    Serial.printf("Touch HIT GT911 raw(%d,%d) ~ui(%d,%d)\n", raw_x, raw_y,
                  ui_x, ui_y);
  }

  data->point.x = feed_x;
  data->point.y = feed_y;
  data->state = LV_INDEV_STATE_PRESSED;
}

#else

static void soft_write(uint8_t data) {
  for (int i = 7; i >= 0; --i) {
    digitalWrite(CYD_TOUCH_MOSI, (data >> i) & 1);
    digitalWrite(CYD_TOUCH_CLK, HIGH);
    delayMicroseconds(2);
    digitalWrite(CYD_TOUCH_CLK, LOW);
    delayMicroseconds(2);
  }
}

static uint16_t soft_read12() {
  uint16_t v = 0;
  digitalWrite(CYD_TOUCH_CLK, HIGH);
  delayMicroseconds(2);
  digitalWrite(CYD_TOUCH_CLK, LOW);
  delayMicroseconds(2);
  for (int i = 0; i < 12; ++i) {
    digitalWrite(CYD_TOUCH_CLK, HIGH);
    delayMicroseconds(2);
    v = (uint16_t)((v << 1) | (digitalRead(CYD_TOUCH_MISO) ? 1u : 0u));
    digitalWrite(CYD_TOUCH_CLK, LOW);
    delayMicroseconds(2);
  }
  return v;
}

static uint16_t xpt_read(uint8_t cmd) {
  digitalWrite(CYD_TOUCH_CS, LOW);
  soft_write(cmd);
  uint16_t v = soft_read12();
  digitalWrite(CYD_TOUCH_CS, HIGH);
  return v;
}

void touch_init() {
  pinMode(CYD_TOUCH_CS, OUTPUT);
  pinMode(CYD_TOUCH_CLK, OUTPUT);
  pinMode(CYD_TOUCH_MOSI, OUTPUT);
  pinMode(CYD_TOUCH_MISO, INPUT);
  pinMode(CYD_TOUCH_IRQ, INPUT);
  digitalWrite(CYD_TOUCH_CS, HIGH);
  digitalWrite(CYD_TOUCH_CLK, LOW);
  Serial.println("Touch: SoftSPI + diagonal fix (BL/TR)");
}

void touch_read_cb(lv_indev_t * /*indev*/, lv_indev_data_t *data) {
  uint16_t adc_x = xpt_read(0x90);
  uint16_t adc_y = xpt_read(0xD0);
  adc_x = (uint16_t)((adc_x + xpt_read(0x90)) / 2);
  adc_y = (uint16_t)((adc_y + xpt_read(0xD0)) / 2);

  const bool irq = (digitalRead(CYD_TOUCH_IRQ) == LOW);
  const bool in_range =
      (adc_x > 80 && adc_x < 4000 && adc_y > 80 && adc_y < 4000);

  if (!in_range || (!irq && (adc_x < 200 || adc_y < 200))) {
    data->state = LV_INDEV_STATE_RELEASED;
    g_dbg_touch_down = false;
    return;
  }

  const int16_t p_x = (int16_t)adc_x;
  const int16_t p_y = (int16_t)(4095 - adc_y);

  int16_t x = map(p_x, 200, 3700, 1, SCREEN_WIDTH);
  int16_t y = map(p_y, 240, 3800, 1, SCREEN_HEIGHT);
  x = clampi(x, 0, SCREEN_WIDTH - 1);
  y = clampi(y, 0, SCREEN_HEIGHT - 1);

  const int32_t old_ux = y;
  const int32_t old_uy = (SCREEN_WIDTH - 1) - x;
  int16_t ui_x = clampi((old_uy * (UI_HOR_RES - 1)) / (UI_VER_RES - 1), 0,
                        UI_HOR_RES - 1);
  int16_t ui_y = clampi((old_ux * (UI_VER_RES - 1)) / (UI_HOR_RES - 1), 0,
                        UI_VER_RES - 1);

  const int16_t feed_x = (int16_t)((SCREEN_WIDTH - 1) - ui_y);
  const int16_t feed_y = ui_x;

  g_dbg_phys_x = x;
  g_dbg_phys_y = y;
  g_dbg_logic_x = ui_x;
  g_dbg_logic_y = ui_y;
  g_dbg_touch_down = true;

  static uint32_t last_log = 0;
  if (millis() - last_log > 80) {
    last_log = millis();
    Serial.printf("Touch UI(%d,%d)\n", ui_x, ui_y);
  }

  data->point.x = feed_x;
  data->point.y = feed_y;
  data->state = LV_INDEV_STATE_PRESSED;
}

#endif