#include <Arduino.h>
#include <WiFi.h>
#include <HTTPClient.h>
#include <ArduinoJson.h>

#include "display_config.h"
#include "renderer_lcd.h"
#include "config.h"
#include "captive_portal.h"

// ── Display instance ────────────────────────────────────────────────────────
static LGFX_WT32_SC01 lcd;

// ── Status bar at bottom ────────────────────────────────────────────────────
static void drawStatusBar(const char* status, uint32_t color = LCD_LABEL) {
    lcd.fillRect(0, 300, 480, 20, 0x0000);
    lcd.setTextSize(1.0f);
    lcd.setTextColor(color);
    lcd.setTextDatum(lgfx::bottom_left);
    lcd.drawString(status, 4, 318);
}

// ── Show error full screen ──────────────────────────────────────────────────
static void showError(const char* message) {
    Serial.printf("[Error] %s\n", message);
    lcd.fillScreen(0x0000);
    lcd.setTextSize(2.0f);
    lcd.setTextColor(TFT_RED);
    lcd.setTextDatum(lgfx::middle_center);
    lcd.drawString("FEHLER", 240, 140);
    lcd.setTextSize(1.2f);
    lcd.setTextColor(LCD_TEXT);
    lcd.drawString(message, 240, 170);
}

// ── Show setup instructions on LCD ──────────────────────────────────────────
static void showSetupScreen() {
    lcd.fillScreen(0x0000);
    lcd.setTextSize(2.0f);
    lcd.setTextColor(LCD_ACCENT);
    lcd.setTextDatum(lgfx::middle_center);
    lcd.drawString("EPaper Setup", 240, 80);
    lcd.setTextSize(1.2f);
    lcd.setTextColor(LCD_TEXT);
    lcd.drawString("Mit 'EPaper-Setup' WLAN verbinden", 240, 140);
    lcd.drawString("und http://192.168.4.1 oeffnen", 240, 165);
}

// ── Fetch and render ────────────────────────────────────────────────────────
static bool fetchAndRender(Config& config) {
    String url = config.api_url + "/api/display/" + config.display_id;
    Serial.printf("[HTTP] GET %s\n", url.c_str());
    drawStatusBar("Daten laden...", LCD_ACCENT);

    HTTPClient http;
    http.begin(url);
    http.setTimeout(10000);
    if (config.api_token.length() > 0) {
        http.addHeader("Authorization", "Bearer " + config.api_token);
    }

    int httpCode = http.GET();
    if (httpCode <= 0 || httpCode >= 400) {
        Serial.printf("[HTTP] Error: %d\n", httpCode);
        http.end();
        String errMsg = "HTTP Fehler: " + String(httpCode);
        drawStatusBar(errMsg.c_str(), TFT_RED);
        return false;
    }

    String payload = http.getString();
    http.end();
    Serial.printf("[HTTP] Payload length: %d\n", payload.length());

    // Parse JSON
    JsonDocument doc;
    DeserializationError err = deserializeJson(doc, payload);
    if (err) {
        Serial.printf("[JSON] Parse error: %s\n", err.c_str());
        String errMsg = "JSON Fehler: " + String(err.c_str());
        drawStatusBar(errMsg.c_str(), TFT_RED);
        return false;
    }

    // Extract refresh_sec
    int refreshSec = doc["refresh_sec"] | config.refresh_sec;
    if (refreshSec < 5) refreshSec = 30;
    config.refresh_sec = refreshSec;

    // Render
    JsonArray elements = doc["elements"].as<JsonArray>();

    lcd.fillScreen(LCD_BG);
    renderElementsLCD(lcd, elements);

    // Status bar with last update time
    char timeBuf[40];
    unsigned long sec = millis() / 1000;
    snprintf(timeBuf, sizeof(timeBuf), "Aktualisiert | Refresh: %ds", refreshSec);
    drawStatusBar(timeBuf, LCD_LABEL);

    Serial.println("[Render] Done");
    return true;
}

// ── Setup ───────────────────────────────────────────────────────────────────
void setup() {
    Serial.begin(115200);
    delay(2000);
    Serial.println("\n\n[Boot] WT32-SC01 Plus LCD Display starting...");

    // 1. Init LCD
    lcd.init();
    lcd.setRotation(1); // Landscape: 480x320
    lcd.setBrightness(200);
    lcd.fillScreen(0x0000);
    lcd.setTextSize(1.5f);
    lcd.setTextColor(LCD_TEXT);
    lcd.setTextDatum(lgfx::middle_center);
    lcd.drawString("Starte...", 240, 160);

    // 2. Load config from NVS
    Config config;
    config.load();

    // 3. If not configured → captive portal
    if (!config.isConfigured()) {
        Serial.println("[Boot] Not configured, starting captive portal");
        showSetupScreen();
        startCaptivePortal(config); // never returns
    }

    // 4. Connect WiFi
    lcd.fillScreen(0x0000);
    lcd.drawString("WiFi verbinden...", 240, 160);

    Serial.printf("[WiFi] Connecting to %s\n", config.wifi_ssid.c_str());
    WiFi.mode(WIFI_STA);
    WiFi.begin(config.wifi_ssid.c_str(), config.wifi_password.c_str());

    int attempts = 0;
    while (WiFi.status() != WL_CONNECTED && attempts < 30) {
        delay(500);
        Serial.print(".");
        ++attempts;
    }
    Serial.println();

    if (WiFi.status() != WL_CONNECTED) {
        showError("WiFi Verbindung fehlgeschlagen");
        delay(10000);
        ESP.restart();
        return;
    }
    Serial.printf("[WiFi] Connected, IP: %s\n", WiFi.localIP().toString().c_str());

    // 5. Initial fetch
    if (!fetchAndRender(config)) {
        showError("Daten konnten nicht geladen werden");
    }
}

// ── Loop: periodic refresh (no deep sleep for LCD) ──────────────────────────
static unsigned long lastUpdate = 0;
static Config loopConfig;
static bool configLoaded = false;

void loop() {
    if (!configLoaded) {
        loopConfig.load();
        configLoaded = true;
        lastUpdate = millis();
    }

    unsigned long now = millis();
    unsigned long intervalMs = (unsigned long)loopConfig.refresh_sec * 1000UL;

    if (now - lastUpdate >= intervalMs) {
        lastUpdate = now;
        if (WiFi.status() != WL_CONNECTED) {
            Serial.println("[WiFi] Reconnecting...");
            WiFi.reconnect();
            delay(5000);
        }
        if (WiFi.status() == WL_CONNECTED) {
            fetchAndRender(loopConfig);
        } else {
            drawStatusBar("WiFi getrennt!", TFT_RED);
        }
    }

    // Touch handling: tap to force refresh
    lgfx::touch_point_t tp;
    if (lcd.getTouch(&tp)) {
        Serial.println("[Touch] Manual refresh triggered");
        drawStatusBar("Manuell aktualisieren...", LCD_ACCENT);
        delay(300); // debounce
        if (WiFi.status() == WL_CONNECTED) {
            fetchAndRender(loopConfig);
        }
        lastUpdate = millis();
    }

    delay(50); // small delay for touch responsiveness
}