#include "ShutterController.h"
#include <Arduino.h>

/// <summary>
/// Non-blocking delay that yields to WiFi stack regularly.
/// For delays < 2 seconds, uses blocking delay directly.
/// For longer delays, breaks into 2-second chunks and feeds the watchdog.
/// </summary>
void ShutterController::nonBlockingDelay(unsigned long ms)
{
    if (ms < 1000)
    {
        delay(ms);
        return;
    }
    
    unsigned long startTime = millis();
    unsigned long remaining = 0;
    unsigned long delayTime = 0;
    
    while (millis() - startTime < ms)
    {
        remaining = ms - (millis() - startTime);
        delayTime = (remaining < 1000) ? remaining : 1000;
        delay(delayTime);
        ESP.wdtFeed();
    }
}

/// <summary>
/// Constructs a ShutterController instance with specified GPIO pins.
/// </summary>
ShutterController::ShutterController(uint8_t focusPin, uint8_t shutterPin)
    : focusPin(focusPin), shutterPin(shutterPin), isFocusPressed(false)
{
}

/// <summary>
/// Performs a half press of the shutter to initiate focus.
/// Sets the focus pin HIGH and marks focus as pressed.
/// </summary>
void ShutterController::halfPress()
{
    digitalWrite(focusPin, HIGH);
    isFocusPressed = true;
}

/// <summary>
/// Performs a full press of the shutter to take a photo.
/// Automatically half-presses the shutter if not already pressed.
/// Sets the shutter pin HIGH to simulate a full button press.
/// </summary>
void ShutterController::fullPress()
{
    if (!isFocusPressed)
    {
        halfPress();
        nonBlockingDelay(1000);
    }
    
    digitalWrite(shutterPin, HIGH);
}

/// <summary>
/// Presses the shutter fully, waits for the specified delay, then releases.
/// Automatically returns to neutral position after the delay.
/// </summary>
/// <param name="ms">Delay in milliseconds between full press and release</param>
void ShutterController::pressFullWithDelay(int ms)
{
    fullPress();
    nonBlockingDelay(ms);
    unPress();
}

/// <summary>
/// Releases the shutter and returns to neutral position.
/// Sets both focus and shutter pins LOW and updates the focus state.
/// </summary>
void ShutterController::unPress()
{
    digitalWrite(shutterPin, LOW);
    digitalWrite(focusPin, LOW);
    isFocusPressed = false;
}

/// <summary>
/// Takes multiple photos in sequence with configurable timing.
/// Ensures focus is locked before taking photos, then executes the sequence.
/// </summary>
/// <param name="ms">Duration of each full press in milliseconds</param>
/// <param name="count">Number of photos to take</param>
/// <param name="delayMs">Delay between consecutive shots in milliseconds</param>
void ShutterController::multipleShoot(int ms, int count, int delayMs)
{
    if (!isFocusPressed)
    {
        halfPress();
        nonBlockingDelay(1000);
    }
    
    while (count > 0)
    {
        fullPress();
        nonBlockingDelay(ms);
        digitalWrite(shutterPin, LOW);
        count--;
        if (count > 0)
        {
            nonBlockingDelay(delayMs);
        }
    }
}

/// <summary>
/// Returns the current focus press state.
/// </summary>
/// <returns>True if focus is currently pressed, false otherwise</returns>
bool ShutterController::getFocusPressedState() const
{
    return isFocusPressed;
}