otaUpdate.cpp

#include "otaUpdate.h"

#include <ArduinoJson.h>
#include <ArduinoOTA.h>
#include <ESPmDNS.h>
#include <SPIFFS.h>       // filesystem usage in /api/status
#include <Update.h>
#include <WebServer.h>
#include <WiFi.h>
#include <soc/soc_caps.h> // SOC_TEMP_SENSOR_SUPPORTED

#include "ClockLogic.h"         // tft, backlightLevel, SHOW_24HOUR, ...
#include "clockFaces.h"         // FACE_COUNT, clockFaceName
#include "genericBaseProject.h" // BACKLIGHT_PIN, NTP sync counters
#include "holidayService.h"     // holidayZonesLoaded - /api/status
#include "marketHolidays.h"     // marketHolidaysFetchedInfo - /api/status
#include "uiPages.h"            // TZ_PRESETS, applyZoneSelection, resetReasonText
#include "weatherService.h"     // weatherAgeMinutes
#include "wifiWatch.h"          // outage history - /api/status

// OTA_PASSWORD (optional) lives in the untracked secrets.h.
#if __has_include("secrets.h")
#include "secrets.h"
#endif

volatile bool otaInProgress = false;

static WebServer webServer(80);

static int otaLastPct = -1;

// Web-upload state, valid between UPLOAD_FILE_START and the completion handler
static bool webUploadAuthorized = false;
static size_t webUpdateExpectedSize = 0;
static bool webUpdateOk = false;
static String webUpdateError;

/*-------- Shared TFT progress screen ----------*/

static void drawOtaScreen(const String &line, uint16_t color)
{
    tft.fillScreen(TFT_BLACK);
    tft.setTextFont(2);
    tft.setTextSize(1);
    tft.setTextDatum(MC_DATUM);
    tft.setTextColor(color, TFT_BLACK);
    tft.drawString(line, 160, 100);
}

static void drawOtaProgressFrame()
{
    otaLastPct = -1;
    tft.drawRect(58, 120, 204, 18, TFT_WHITE);
}

static void drawOtaProgressPct(int pct)
{
    if (pct < 0) pct = 0;
    if (pct > 100) pct = 100;
    if (pct == otaLastPct) return;
    otaLastPct = pct;
    tft.fillRect(60, 122, pct * 2, 14, TFT_GREEN);
    tft.setTextFont(2);
    tft.setTextSize(1);
    tft.setTextDatum(TC_DATUM);
    tft.setTextColor(TFT_WHITE, TFT_BLACK);
    tft.drawString(String(pct) + " %  ", 160, 146);
}

// Failure exit shared by both update paths: show the error, then hand the
// screen back to the clock with a full repaint.
static void otaFailScreen(const String &line)
{
    otaInProgress = false;
    drawOtaScreen(line, TFT_RED);
    delay(2000);
    switchToScreen(SCREEN_HOME);
}

/*-------- ArduinoOTA (espota / IDE network port) ----------*/

static void setupArduinoOTA()
{
    // Configurable so two clocks on one network don't collide on
    // "<hostname>.local" (web settings page; applied on boot).
    ArduinoOTA.setHostname(projectConfig.hostname.c_str());
#ifdef OTA_PASSWORD
    if (strlen(OTA_PASSWORD) > 0)
    {
        ArduinoOTA.setPassword(OTA_PASSWORD);
    }
#endif

    ArduinoOTA.onStart([]() {
        otaInProgress = true;
        drawOtaScreen(ArduinoOTA.getCommand() == U_FLASH
                          ? "OTA update: receiving firmware..."
                          : "OTA update: receiving filesystem...",
                      TFT_CYAN);
        drawOtaProgressFrame();
    });

    ArduinoOTA.onProgress([](unsigned int progress, unsigned int total) {
        drawOtaProgressPct(total > 0 ? (int)((progress * 100ULL) / total) : 0);
    });

    ArduinoOTA.onEnd([]() {
        drawOtaScreen("OTA update complete - rebooting...", TFT_GREEN);
    });

    ArduinoOTA.onError([](ota_error_t error) {
        const char *msg = error == OTA_AUTH_ERROR      ? "auth failed"
                          : error == OTA_BEGIN_ERROR   ? "begin failed"
                          : error == OTA_CONNECT_ERROR ? "connect failed"
                          : error == OTA_RECEIVE_ERROR ? "receive failed"
                                                       : "end failed";
        Log.println(String("OTA error: ") + msg);
        otaFailScreen(String("OTA update failed (") + msg + ")");
    });

    ArduinoOTA.begin();
}

/*-------- Web updater (browser firmware upload) ----------*/

// Self-contained page: file picker, browser-side progress bar, result text.
// %BUILD% is replaced with the compile timestamp when served.
static const char UPDATE_PAGE[] PROGMEM = R"rawliteral(<!DOCTYPE html>
<html><head><meta charset="utf-8">
<meta name="viewport" content="width=device-width,initial-scale=1">
<title>World Clock firmware update</title>
<style>
body{font-family:system-ui,sans-serif;background:#111;color:#eee;display:flex;justify-content:center;padding:2rem}
.card{max-width:26rem;width:100%;background:#1c1c1c;border:1px solid #333;border-radius:10px;padding:1.5rem}
h1{font-size:1.2rem;margin:0 0 .3rem}
p{color:#aaa;font-size:.85rem;margin:.4rem 0}
code{color:#ccc}
input[type=file]{width:100%;margin:.8rem 0;color:#ccc}
button{width:100%;padding:.6rem;border:0;border-radius:6px;background:#0a84ff;color:#fff;font-size:1rem;cursor:pointer}
button:disabled{background:#444;cursor:default}
#bar{height:10px;background:#333;border-radius:5px;overflow:hidden;margin:1rem 0 .4rem;display:none}
#fill{height:100%;width:0;background:#30d158;transition:width .15s}
#msg{font-size:.9rem;min-height:1.2em}
.err{color:#ff6961}.ok{color:#30d158}
</style></head><body><div class="card">
<h1>ESP32 World Clock</h1>
<p>Running build: %BUILD% &middot; <a href="/" style="color:#0a84ff">Settings</a></p>
<p>Select a firmware image (<code>firmware.bin</code> from PlatformIO's
<code>.pio/build/cyd/</code>, or Arduino IDE &gt; Sketch &gt; Export Compiled
Binary) and press Update. Keep the device powered until it reboots.</p>
<form id="f">
<input type="file" id="file" accept=".bin" required>
<button id="btn" type="submit">Update firmware</button>
</form>
<div id="bar"><div id="fill"></div></div>
<div id="msg"></div>
</div>
<script>
var f=document.getElementById('f'),file=document.getElementById('file'),
btn=document.getElementById('btn'),bar=document.getElementById('bar'),
fill=document.getElementById('fill'),msg=document.getElementById('msg');
f.addEventListener('submit',function(e){e.preventDefault();
var fw=file.files[0];if(!fw)return;
btn.disabled=true;bar.style.display='block';fill.style.width='0';
msg.textContent='Uploading...';msg.className='';
var x=new XMLHttpRequest();
x.open('POST','/update?size='+fw.size);
x.upload.onprogress=function(ev){if(ev.lengthComputable)
fill.style.width=Math.round(ev.loaded*100/ev.total)+'%';};
x.onload=function(){if(x.status==200){
msg.textContent='Success - the clock is rebooting; give it ~20 seconds.';
msg.className='ok';}else{
msg.textContent='Update failed: '+x.responseText;
msg.className='err';btn.disabled=false;}};
x.onerror=function(){msg.textContent='Connection lost.';btn.disabled=false;};
var d=new FormData();d.append('firmware',fw);x.send(d);});
</script></body></html>
)rawliteral";

// True if the request may proceed; otherwise a 401 challenge has been sent.
static bool webAuthenticate()
{
#ifdef OTA_PASSWORD
    if (strlen(OTA_PASSWORD) > 0 && !webServer.authenticate("admin", OTA_PASSWORD))
    {
        webServer.requestAuthentication();
        return false;
    }
#endif
    return true;
}

static void handleUpdatePage()
{
    if (!webAuthenticate()) return;
    String page = FPSTR(UPDATE_PAGE);
    page.replace("%BUILD%", String(__DATE__) + " " + __TIME__);
    webServer.send(200, "text/html", page);
}

// Streams the multipart upload into the OTA partition chunk by chunk. Runs on
// the main loop core (webServer.handleClient), so drawing on the TFT is safe;
// the clock is intentionally frozen behind the progress screen meanwhile.
static void handleUpdateUpload()
{
    HTTPUpload &up = webServer.upload();

    if (up.status == UPLOAD_FILE_START)
    {
        webUploadAuthorized = true;
#ifdef OTA_PASSWORD
        if (strlen(OTA_PASSWORD) > 0)
        {
            webUploadAuthorized = webServer.authenticate("admin", OTA_PASSWORD);
        }
#endif
        if (!webUploadAuthorized) return;

        otaInProgress = true;
        webUpdateOk = false;
        webUpdateError = "";
        // The page passes the exact file size as ?size= so the on-screen
        // percentage is accurate (multipart Content-Length would overshoot).
        webUpdateExpectedSize = (size_t)webServer.arg("size").toInt();

        Log.println("Web update started: " + up.filename);
        drawOtaScreen("Web update: receiving firmware...", TFT_CYAN);
        drawOtaProgressFrame();

        if (!Update.begin(UPDATE_SIZE_UNKNOWN))
        {
            webUpdateError = Update.errorString();
        }
    }
    else if (up.status == UPLOAD_FILE_WRITE)
    {
        if (!webUploadAuthorized || webUpdateError.length() > 0) return;
        if (Update.write(up.buf, up.currentSize) != up.currentSize)
        {
            webUpdateError = Update.errorString();
        }
        else if (webUpdateExpectedSize > 0)
        {
            drawOtaProgressPct((int)((up.totalSize * 100ULL) / webUpdateExpectedSize));
        }
    }
    else if (up.status == UPLOAD_FILE_END)
    {
        if (!webUploadAuthorized) return;
        if (webUpdateError.length() == 0 && Update.end(true))
        {
            webUpdateOk = true;
            Log.println("Web update received: " + String(up.totalSize) + " bytes");
        }
        else if (webUpdateError.length() == 0)
        {
            webUpdateError = Update.errorString();
        }
    }
    else if (up.status == UPLOAD_FILE_ABORTED)
    {
        Update.abort();
        webUpdateError = "upload aborted";
    }
}

// Completion handler: runs after the upload callback has seen the whole body.
static void handleUpdateResult()
{
    if (!webUploadAuthorized)
    {
        webServer.requestAuthentication();
        return;
    }

    if (webUpdateOk)
    {
        webServer.sendHeader("Connection", "close");
        webServer.send(200, "text/plain", "OK - rebooting");
        drawOtaScreen("Web update complete - rebooting...", TFT_GREEN);
        delay(750); // let the response reach the browser
        ESP.restart();
    }
    else
    {
        String err = webUpdateError.length() > 0 ? webUpdateError : "update failed";
        webServer.send(500, "text/plain", err);
        Log.println("Web update failed: " + err);
        otaFailScreen("Web update failed");
    }
}

/*-------- Web settings page ----------*/
// Configure the clock from a browser: the same settings as the on-device
// touch UI (timezones, face, formats, brightness). Served at "/"; changes
// are applied on the main loop core (webServer.handleClient runs there), so
// it can safely reuse the touch UI's apply/persist functions.

static const char SETTINGS_PAGE_HEAD[] PROGMEM = R"rawliteral(<!DOCTYPE html>
<html><head><meta charset="utf-8">
<meta name="viewport" content="width=device-width,initial-scale=1">
<title>World Clock settings</title>
<style>
body{font-family:system-ui,sans-serif;background:#111;color:#eee;display:flex;justify-content:center;padding:2rem}
.card{max-width:26rem;width:100%;background:#1c1c1c;border:1px solid #333;border-radius:10px;padding:1.5rem}
h1{font-size:1.2rem;margin:0 0 .3rem}
p{color:#aaa;font-size:.85rem;margin:.4rem 0}
a{color:#0a84ff}
label{display:block;color:#ccc;font-size:.85rem;margin:.8rem 0 0}
select,input[type=range],input[type=text]{width:100%;margin:.3rem 0 0;padding:.4rem;background:#2a2a2a;color:#eee;border:1px solid #444;border-radius:6px;box-sizing:border-box}
.row{display:flex;gap:.6rem}.row label{flex:1;margin-top:.8rem}
button{width:100%;margin-top:1.2rem;padding:.6rem;border:0;border-radius:6px;background:#0a84ff;color:#fff;font-size:1rem;cursor:pointer}
</style></head><body><div class="card">
<h1>ESP32 World Clock</h1>
)rawliteral";

// One preset-city <select> for a quadrant slot, current selection marked.
static void appendZoneSelect(String &page, const char *label, int slot)
{
    page += "<label>" + String(label) + "<select name=\"zone" + String(slot) + "\">";
    bool matched = false;
    for (int p = 0; p < TZ_PRESET_COUNT; p++)
    {
        bool sel = worldZones[slot].timezone == TZ_PRESETS[p].tz;
        matched |= sel;
        page += "<option value=\"" + String(p) + "\"" + (sel ? " selected" : "") + ">" +
                TZ_PRESETS[p].name + " (" + TZ_PRESETS[p].tz + ")</option>";
    }
    if (!matched)
    {
        // Zone outside the preset list (e.g. hand-edited config): offer to
        // keep it; value -1 is ignored by the POST handler.
        page += "<option value=\"-1\" selected>keep " + worldZones[slot].name + "</option>";
    }
    page += "</select></label>";
}

// 0:00 .. 23:00 <option> rows for the night-window hour selects.
static void appendHourOptions(String &page, int selected)
{
    for (int h = 0; h < 24; h++)
    {
        page += "<option value=\"" + String(h) + "\"" +
                (h == selected ? " selected" : "") + ">" + String(h) + ":00</option>";
    }
}

static void handleSettingsPage()
{
    if (!webAuthenticate()) return;

    String page;
    page.reserve(12288);
    page += FPSTR(SETTINGS_PAGE_HEAD);
    page += "<p>Running build: " + String(__DATE__) + " " + __TIME__ +
            " &middot; <a href=\"/update\">Firmware update</a>"
            " &middot; <a href=\"/logs\">Logs</a>"
            " &middot; <a href=\"/api/status\">Status JSON</a></p>";
    page += "<form method=\"POST\" action=\"/settings\">";

    static const char *slotLabels[4] = {"Top-left clock (home)", "Top-right clock",
                                        "Bottom-left clock", "Bottom-right clock"};
    for (int i = 0; i < 4; i++)
    {
        appendZoneSelect(page, slotLabels[i], i);
    }

    page += "<label>Clock face<select name=\"face\">";
    for (int f = 0; f < FACE_COUNT; f++)
    {
        page += "<option value=\"" + String(f) + "\"" +
                (projectConfig.clockFace == f ? " selected" : "") + ">" +
                clockFaceName(f) + "</option>";
    }
    page += "</select></label>";

    page += "<label>Clock format<select name=\"clk\">";
    page += String("<option value=\"24\"") + (SHOW_24HOUR ? " selected" : "") + ">24 hour</option>";
    page += String("<option value=\"12\"") + (!SHOW_24HOUR ? " selected" : "") + ">12 hour (AM/PM)</option>";
    page += "</select></label>";

    page += "<label>Date format<select name=\"date\">";
    page += String("<option value=\"dmy\"") + (NOT_US_DATE ? " selected" : "") + ">DD/MM/YY</option>";
    page += String("<option value=\"mdy\"") + (!NOT_US_DATE ? " selected" : "") + ">MM/DD/YY</option>";
    page += "</select></label>";

    int pct = map(backlightLevel, 5, 255, 0, 100);
    page += "<label>Brightness (<span id=\"bv\">" + String(pct) + "</span>%)"
            "<input type=\"range\" name=\"bri\" min=\"5\" max=\"255\" value=\"" +
            String(backlightLevel) + "\" oninput=\"document.getElementById('bv')"
            ".textContent=Math.round((this.value-5)*100/250)\"></label>";

    // Night dimming: window (home-zone hours) + the dimmed level
    page += "<div class=\"row\"><label>Night dim from<select name=\"nstart\">";
    appendHourOptions(page, projectConfig.nightStartHour);
    page += "</select></label><label>until<select name=\"nend\">";
    appendHourOptions(page, projectConfig.nightEndHour);
    page += "</select></label></div>";
    int npct = map(constrain(projectConfig.nightBrightness, 1, 255), 1, 255, 0, 100);
    page += "<label>Night brightness (<span id=\"nv\">" + String(npct) + "</span>%)"
            "<input type=\"range\" name=\"nbri\" min=\"1\" max=\"255\" value=\"" +
            String(constrain(projectConfig.nightBrightness, 1, 255)) +
            "\" oninput=\"document.getElementById('nv')"
            ".textContent=Math.round((this.value-1)*100/254)\"></label>";
    page += "<p>Night brightness is used when the room is dark (light sensor), "
            "or inside the window above (home-zone time) when the sensor is "
            "unavailable. Equal hours disable the schedule.</p>";

    page += "<label>Hostname (mDNS \"&lt;name&gt;.local\", applied after reboot)"
            "<input type=\"text\" name=\"host\" maxlength=\"32\" value=\"" +
            projectConfig.hostname + "\"></label>";

    page += "<button type=\"submit\">Save</button></form>"
            "<p>Saving a brightness change pauses auto-brightness for 2 hours, "
            "same as the on-device controls.</p>";

    // Config backup/restore (/api/config). Restore expects a previously
    // downloaded backup; the device saves it and reboots to apply.
    page += "<p><a href=\"/api/config\" download=\"worldclock-config.json\">Backup config"
            "</a> &middot; restore: <input type=\"file\" id=\"cfg\" accept=\".json\" "
            "style=\"width:auto;color:#ccc\"></p>"
            "<script>document.getElementById('cfg').addEventListener('change',"
            "async function(){if(!this.files[0])return;"
            "var r=await fetch('/api/config',{method:'POST',body:await this.files[0].text()});"
            "alert(await r.text());});</script>";

    page += "</div></body></html>";
    webServer.send(200, "text/html", page);
}

static void handleSettingsPost()
{
    if (!webAuthenticate()) return;

    // Timezone changes first - each one persists the config and re-fetches
    // the zone definition (brief blocking network call per changed zone).
    for (int i = 0; i < 4; i++)
    {
        String arg = webServer.arg("zone" + String(i));
        if (arg.length() == 0) continue;
        int idx = arg.toInt();
        if (idx < 0 || idx >= TZ_PRESET_COUNT) continue; // -1 = keep current
        if (worldZones[i].timezone == TZ_PRESETS[idx].tz &&
            worldZones[i].name == TZ_PRESETS[idx].name) continue;
        applyZoneSelection(i, TZ_PRESETS[idx]);
    }

    // Absent fields keep their current value, so a partial POST (scripted
    // curl, say) can't silently flip unrelated settings.
    bool wants24 = webServer.hasArg("clk") ? webServer.arg("clk") != "12" : SHOW_24HOUR;
    bool wantsDmy = webServer.hasArg("date") ? webServer.arg("date") != "mdy" : NOT_US_DATE;
    if (wants24 != SHOW_24HOUR || wantsDmy != NOT_US_DATE)
    {
        SHOW_24HOUR = wants24;
        NOT_US_DATE = wantsDmy;
        saveDisplayPrefs();
    }

    if (webServer.hasArg("face"))
    {
        int face = webServer.arg("face").toInt();
        if (face >= 0 && face < FACE_COUNT && face != projectConfig.clockFace)
        {
            projectConfig.clockFace = face;
            projectConfig.saveConfigFile();
        }
    }

    int bri = webServer.arg("bri").toInt();
    if (bri >= 5 && bri <= 255 && bri != backlightLevel)
    {
        backlightLevel = bri;
        analogWrite(BACKLIGHT_PIN, backlightLevel);
        manualBrightnessUntil = millis() + MANUAL_BRIGHTNESS_HOLD_MS;
        projectConfig.brightness = backlightLevel;
        projectConfig.saveConfigFile();
    }

    // Night dimming + hostname: gathered into a single config save
    bool cfgDirty = false;
    if (webServer.hasArg("nstart"))
    {
        int v = constrain(webServer.arg("nstart").toInt(), 0, 23);
        if (v != projectConfig.nightStartHour)
        {
            projectConfig.nightStartHour = v;
            cfgDirty = true;
        }
    }
    if (webServer.hasArg("nend"))
    {
        int v = constrain(webServer.arg("nend").toInt(), 0, 23);
        if (v != projectConfig.nightEndHour)
        {
            projectConfig.nightEndHour = v;
            cfgDirty = true;
        }
    }
    if (webServer.hasArg("nbri"))
    {
        int v = webServer.arg("nbri").toInt();
        if (v >= 1 && v <= 255 && v != projectConfig.nightBrightness)
        {
            projectConfig.nightBrightness = v;
            cfgDirty = true;
        }
    }
    if (webServer.hasArg("host"))
    {
        String h = sanitizeHostname(webServer.arg("host"));
        if (h != projectConfig.hostname)
        {
            projectConfig.hostname = h;
            cfgDirty = true;
            Log.println("Hostname changed to \"" + h + "\" - applies after the next reboot");
        }
    }
    if (cfgDirty)
    {
        projectConfig.saveConfigFile();
    }

    // Repaint the home screen with the new settings, whatever page the
    // on-device UI was showing.
    switchToScreen(SCREEN_HOME);
    Log.println("Settings applied from the web page");

    webServer.sendHeader("Location", "/");
    webServer.send(303, "text/plain", "Saved");
}

/*-------- Config backup / restore ----------*/
// GET /api/config downloads the settings JSON; POST the same JSON back to
// restore it (clone a second device, or recover after a partition-scheme
// change wipes SPIFFS). The device saves the imported config and reboots so
// zones, hostname and formats all apply through the normal boot path.

static void handleApiConfigGet()
{
    if (!webAuthenticate()) return;
    webServer.sendHeader("Content-Disposition",
                         "attachment; filename=\"worldclock-config.json\"");
    webServer.send(200, "application/json", projectConfig.toJsonString());
}

static void handleApiConfigPost()
{
    if (!webAuthenticate()) return;

    String body = webServer.arg("plain");
    if (body.length() == 0 || body.length() > 4096)
    {
        webServer.send(400, "text/plain",
                       "Expected the config JSON (a /api/config backup) as the request body");
        return;
    }
    if (!projectConfig.applyFromJsonString(body))
    {
        webServer.send(400, "text/plain",
                       "Not a valid config JSON - no recognized settings found");
        return;
    }
    projectConfig.saveConfigFile();
    Log.println("Config imported via /api/config - rebooting to apply");
    webServer.sendHeader("Connection", "close");
    webServer.send(200, "text/plain", "OK - config saved, rebooting to apply it");
    delay(750); // let the response reach the client
    ESP.restart();
}

// Diagnostics as JSON - the System status page, but scriptable.
static void handleApiStatus()
{
    if (!webAuthenticate()) return;

    DynamicJsonDocument doc(3072);
    doc["hostname"] = projectConfig.hostname;
    doc["ip"] = WiFi.localIP().toString();
    doc["ssid"] = WiFi.SSID();
    doc["rssiDbm"] = WiFi.RSSI();
    doc["mac"] = WiFi.macAddress();
    doc["gateway"] = WiFi.gatewayIP().toString();
    doc["dns"] = WiFi.dnsIP().toString();
    doc["wifiChannel"] = WiFi.channel();
    doc["wifiDrops"] = wifiDropCount();
    doc["wifiOfflineSec"] = (long)(wifiOfflineDurationMs() / 1000UL);
    doc["resetReason"] = resetReasonText();
    doc["sdk"] = ESP.getSdkVersion();
    doc["spiffsUsedBytes"] = SPIFFS.usedBytes();
    doc["spiffsTotalBytes"] = SPIFFS.totalBytes();
    doc["chip"] = String(ESP.getChipModel()) + " r" + String(ESP.getChipRevision());
    doc["cpuMhz"] = ESP.getCpuFreqMHz();
#if SOC_TEMP_SENSOR_SUPPORTED
    doc["cpuTempC"] = temperatureRead();
#endif
    doc["flashSizeBytes"] = ESP.getFlashChipSize();
    doc["sketchSizeBytes"] = ESP.getSketchSize();
    doc["sketchSlotBytes"] = ESP.getSketchSize() + ESP.getFreeSketchSpace();
    doc["uptimeSec"] = millis() / 1000UL;
    doc["freeHeapBytes"] = ESP.getFreeHeap();
    doc["minFreeHeapBytes"] = ESP.getMinFreeHeap();
    doc["maxAllocHeapBytes"] = ESP.getMaxAllocHeap();
    doc["ntpSyncs"] = syncCount;
    doc["lastSyncAgoMin"] = (syncCount > 0)
                                ? (long)((millis() - lastSyncTime) / 60000UL)
                                : -1;
    doc["utc"] = UTC.dateTime("Y-m-d H:i:s");
    doc["build"] = String(__DATE__) + " " + __TIME__;
    doc["clockFace"] = clockFaceName(projectConfig.clockFace);
    doc["brightness"] = backlightLevel;
    doc["weatherAgeMin"] = weatherAgeMinutes();

    long calAgeDays = -1;
    doc["marketHolidaySource"] = marketHolidaysFetchedInfo(calAgeDays) ? "fetched" : "compiled";
    if (calAgeDays >= 0)
    {
        doc["marketHolidayAgeDays"] = calAgeDays;
    }
    int holidayZonesEligible = 0;
    doc["holidayZonesLoaded"] = holidayZonesLoaded(holidayZonesEligible);
    doc["holidayZonesEligible"] = holidayZonesEligible;

    bool ldrTrusted, ldrDark;
    int ldrSmoothed;
    if (getLdrState(ldrTrusted, ldrDark, ldrSmoothed))
    {
        doc["ldrTrusted"] = ldrTrusted;
        if (ldrTrusted)
        {
            doc["ldrRoomDark"] = ldrDark;
        }
    }
    unsigned long nowMs = millis();
    doc["manualBrightnessHoldMin"] =
        (manualBrightnessUntil > nowMs) ? (long)((manualBrightnessUntil - nowMs) / 60000UL) : 0;

    JsonArray zones = doc.createNestedArray("zones");
    for (int i = 0; i < 4; i++)
    {
        JsonObject z = zones.createNestedObject();
        z["name"] = worldZones[i].name;
        z["tz"] = worldZones[i].timezone;
        if (worldZones[i].lastMarketStatus.length() > 0)
        {
            z["market"] = worldZones[i].lastMarketStatus;
        }
    }

    String out;
    serializeJson(doc, out);
    webServer.send(200, "application/json", out);
}

/*-------- Log viewer ----------*/
// The tail of the in-RAM log ring (logBuffer.h) in the browser: /api/logs
// returns it as plain text, /logs is a small auto-refreshing viewer.

static const char LOGS_PAGE[] PROGMEM = R"rawliteral(<!DOCTYPE html>
<html><head><meta charset="utf-8">
<meta name="viewport" content="width=device-width,initial-scale=1">
<title>World Clock logs</title>
<style>
body{font-family:ui-monospace,Consolas,monospace;background:#111;color:#ddd;margin:0;padding:1rem}
h1{font-size:1rem;font-family:system-ui,sans-serif;margin:0 .0 .4rem}
a{color:#0a84ff;font-family:system-ui,sans-serif;font-size:.85rem;font-weight:normal}
label{font-family:system-ui,sans-serif;font-size:.8rem;color:#aaa}
pre{white-space:pre-wrap;word-break:break-all;font-size:.78rem;line-height:1.4;margin:.6rem 0 0}
</style></head><body>
<h1>ESP32 World Clock logs &middot; <a href="/">settings</a></h1>
<label><input type="checkbox" id="auto" checked> auto-refresh (2s), timestamps are uptime</label>
<pre id="l">loading...</pre>
<script>
var l=document.getElementById('l'),auto=document.getElementById('auto');
async function load(){
  try{
    var r=await fetch('/api/logs');
    var nearBottom=(window.innerHeight+window.scrollY)>=(document.body.scrollHeight-60);
    l.textContent=await r.text();
    if(nearBottom)window.scrollTo(0,document.body.scrollHeight);
  }catch(e){}
}
load();
setInterval(function(){if(auto.checked)load();},2000);
</script></body></html>
)rawliteral";

static void handleLogsPage()
{
    if (!webAuthenticate()) return;
    webServer.send(200, "text/html", FPSTR(LOGS_PAGE));
}

static void handleApiLogs()
{
    if (!webAuthenticate()) return;
    webServer.send(200, "text/plain", logTail(6144));
}

static void setupWebUpdater()
{
    webServer.on("/", HTTP_GET, handleSettingsPage);
    webServer.on("/settings", HTTP_POST, handleSettingsPost);
    webServer.on("/api/status", HTTP_GET, handleApiStatus);
    webServer.on("/api/config", HTTP_GET, handleApiConfigGet);
    webServer.on("/api/config", HTTP_POST, handleApiConfigPost);
    webServer.on("/logs", HTTP_GET, handleLogsPage);
    webServer.on("/api/logs", HTTP_GET, handleApiLogs);
    webServer.on("/update", HTTP_GET, handleUpdatePage);
    webServer.on("/update", HTTP_POST, handleUpdateResult, handleUpdateUpload);
    webServer.onNotFound([]() {
        webServer.sendHeader("Location", "/");
        webServer.send(302, "text/plain", "");
    });
    webServer.begin();

    // ArduinoOTA.begin() already registered the configured hostname on mDNS;
    // advertise the web pages on it too.
    MDNS.addService("http", "tcp", 80);
}

/*-------- Public entry points ----------*/

void setupOTA()
{
    setupArduinoOTA();
    setupWebUpdater();
    Log.println("OTA updates enabled (hostname: " + projectConfig.hostname +
                   ", espota port 3232)");
    Log.println("Web settings + updater: http://" + WiFi.localIP().toString() +
                   "/ (or http://" + projectConfig.hostname + ".local/)");
}

void handleOTA()
{
    ArduinoOTA.handle();
    webServer.handleClient();
}