WiFi-Connected Photo Carousel

/*
 * Rotating Digital Photo Frame
 * ESP32 DevKit v1 + ILI9488 3.5" SPI TFT (480x320)
 * WiFi AP + Web UI — uses built-in WebServer (no AsyncWebServer needed)
 */

#include <Arduino.h>
#include <SPI.h>
#include <SPIFFS.h>
#include <WiFi.h>
#include <WebServer.h>
#include <TFT_eSPI.h>
#include <JPEGDEC.h>
#include <vector>
#include "html_page.h"

// ─── Pin constants ────────────────────────────────────────────────
#define TFT_CS_PIN   4
#define TFT_DC_PIN   21
#define TFT_RST_PIN  22
#define TFT_BL_PIN   32

// ─── Config ───────────────────────────────────────────────────────
const char* AP_SSID  = "PhotoFrame";
const char* AP_PASS  = "photoframe123";
const int   SLIDE_MS = 5000;

// ─── Forward declarations ─────────────────────────────────────────
int  jpegDrawCB(JPEGDRAW *pDraw);
void rebuildList();
void showPhoto(const String& path);
void showNoPhotos();
void handleRoot();
void handleList();
void handleDelete();
void handleUpload();
void handleUploadBody();

// ─── Globals ──────────────────────────────────────────────────────
TFT_eSPI    tft;
JPEGDEC     jpeg;
WebServer   server(80);

std::vector<String> photoList;
int           currentIndex  = 0;
unsigned long lastSlide     = 0;
bool          photosChanged = false;

// ─── JPEG draw callback ───────────────────────────────────────────
int jpegDrawCB(JPEGDRAW *pDraw) {
    tft.pushImage(pDraw->x, pDraw->y, pDraw->iWidth, pDraw->iHeight,
                  (uint16_t*)pDraw->pPixels);
    return 1;
}

// ─── Rebuild photo list from SPIFFS ───────────────────────────────
void rebuildList() {
    photoList.clear();
    File root = SPIFFS.open("/photos");
    if (!root || !root.isDirectory()) return;
    File f = root.openNextFile();
    while (f) {
        String nm = String(f.name());
        if (nm.endsWith(".jpg") || nm.endsWith(".jpeg") ||
            nm.endsWith(".JPG") || nm.endsWith(".JPEG")) {
            photoList.push_back(nm);
        }
        f = root.openNextFile();
    }
}

// ─── Display helpers ──────────────────────────────────────────────
void showPhoto(const String& path) {
    tft.fillScreen(TFT_BLACK);
    File f = SPIFFS.open(path, "r");
    if (!f) {
        tft.setTextColor(TFT_WHITE, TFT_BLACK);
        tft.setCursor(10, 150); tft.setTextSize(2);
        tft.print("Cannot open: "); tft.println(path);
        return;
    }
    size_t sz = f.size();
    uint8_t* buf = (uint8_t*)malloc(sz);
    if (!buf) {
        f.close();
        tft.setCursor(10, 150);
        tft.setTextColor(TFT_RED, TFT_BLACK); tft.setTextSize(2);
        tft.println("Out of RAM");
        return;
    }
    f.read(buf, sz);
    f.close();
    jpeg.openRAM(buf, (int)sz, jpegDrawCB);
    jpeg.setPixelType(RGB565_BIG_ENDIAN);
    jpeg.decode(0, 0, 0);
    jpeg.close();
    free(buf);
}

void showNoPhotos() {
    tft.fillScreen(TFT_BLACK);
    tft.setTextColor(TFT_WHITE, TFT_BLACK);
    tft.setTextSize(2); tft.setCursor(60, 140);
    tft.println("No photos found.");
    tft.setTextSize(1); tft.setCursor(60, 170);
    tft.println("Connect to WiFi: PhotoFrame");
    tft.setCursor(60, 185);
    tft.println("Open: http://192.168.4.1");
}

// ─── HTTP handlers ────────────────────────────────────────────────
void handleRoot() {
    server.send_P(200, "text/html", HTML_PAGE);
}

void handleList() {
    String json = "[";
    for (int i = 0; i < (int)photoList.size(); i++) {
        if (i) json += ",";
        json += "\"" + photoList[i] + "\"";
    }
    json += "]";
    server.send(200, "application/json", json);
}

void handleDelete() {
    if (!server.hasArg("name")) {
        server.send(400, "text/plain", "Missing name"); return;
    }
    String nm = server.arg("name");
    nm.replace("..", "");
    if (!nm.startsWith("/")) nm = "/photos/" + nm;
    if (SPIFFS.remove(nm)) {
        rebuildList();
        currentIndex = 0; photosChanged = true;
        server.send(200, "text/plain", "Deleted: " + nm);
    } else {
        server.send(404, "text/plain", "Not found: " + nm);
    }
}

// Upload handler — WebServer multipart file upload
static File uploadFile;
void handleUploadBody() {
    HTTPUpload& upload = server.upload();
    if (upload.status == UPLOAD_FILE_START) {
        String filename = upload.filename;
        filename.replace("..", "");
        if (!filename.endsWith(".jpg") && !filename.endsWith(".jpeg") &&
            !filename.endsWith(".JPG") && !filename.endsWith(".JPEG")) return;
        uploadFile = SPIFFS.open("/photos/" + filename, "w");
    } else if (upload.status == UPLOAD_FILE_WRITE) {
        if (uploadFile) uploadFile.write(upload.buf, upload.currentSize);
    } else if (upload.status == UPLOAD_FILE_END) {
        if (uploadFile) {
            uploadFile.close();
            rebuildList();
            currentIndex = 0; photosChanged = true;
        }
    }
}

void handleUpload() {
    server.send(200, "text/plain", "Upload complete!");
}

// ─── Setup ────────────────────────────────────────────────────────
void setup() {
    Serial.begin(115200);

    pinMode(TFT_BL_PIN, OUTPUT);
    digitalWrite(TFT_BL_PIN, HIGH);

    tft.init();
    tft.setRotation(1);
    tft.fillScreen(TFT_BLACK);
    tft.setTextColor(TFT_WHITE, TFT_BLACK);
    tft.setTextSize(2); tft.setCursor(60, 140);
    tft.println("Starting...");

    if (!SPIFFS.begin(true)) {
        tft.setCursor(10, 160);
        tft.setTextColor(TFT_RED, TFT_BLACK);
        tft.println("SPIFFS failed!");
        while (1) delay(1000);
    }

    // Ensure /photos directory exists
    if (!SPIFFS.exists("/photos")) {
        File dir = SPIFFS.open("/photos", "w");
        if (dir) dir.close();
    }

    WiFi.softAP(AP_SSID, AP_PASS);
    Serial.println("AP IP: " + WiFi.softAPIP().toString());

    server.on("/",       HTTP_GET,  handleRoot);
    server.on("/list",   HTTP_GET,  handleList);
    server.on("/delete", HTTP_GET,  handleDelete);
    server.on("/upload", HTTP_POST, handleUpload, handleUploadBody);
    server.begin();

    rebuildList();
    if (!photoList.empty()) showPhoto(photoList[0]);
    else                    showNoPhotos();
    lastSlide = millis();
}

// ─── Loop ─────────────────────────────────────────────────────────
void loop() {
    server.handleClient();

    unsigned long now = millis();
    if (now - lastSlide >= (unsigned long)SLIDE_MS || photosChanged) {
        photosChanged = false;
        rebuildList();
        if (!photoList.empty()) {
            currentIndex = (currentIndex + 1) % (int)photoList.size();
            showPhoto(photoList[currentIndex]);
        } else {
            showNoPhotos();
        }
        lastSlide = now;
    }
}