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

#include <Arduino.h>

/**
 * SoftSPI XPT2046
 * BL↔TR 是矩形主对角线镜像（XY 对调），不是 180°（180° 会搞成 TL↔BR）。
 * 先按 rot2 得到旧 UI，再做对角修正，反变换喂给 LVGL 270。
 */

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 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;
}

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;
}

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);

  // 旧 UI（LVGL270）：(y, 239-x) — 该空间里 BL↔TR，做主对角线镜像
  // (ux,uy) -> (uy*(319/239), ux*(239/319))
  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);

  // 反变换喂 LVGL，使最终落在 (ui_x, ui_y)
  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;
}