/**
 * Display UI Task — aktualisiert SD-Speicher und Frame-Counter
 * 
 * Wird als FreeRTOS-Task gestartet und alle 2 Sekunden:
 *   - SD-Speicher % berechnen + Balken zeichnen
 *   - Frame-Counter groß anzeigen
 *   - Scroller aktualisieren
 */

#include "esp_log.h"
#include "v2x_display.h"
#include "esp_vfs_fat.h"
#include "freertos/FreeRTOS.h"
#include "freertos/task.h"
#include "stdio.h"

static const char *TAG = "v2x-ui";

/* SD-Speicher % berechnen */
static float get_sd_storage_percent(void)
{
    FATFS *fs;
    DWORD free_clusters;
    
    esp_err_t ret = f_getfree(SD_CARD_MOUNT_POINT, &free_clusters, &fs);
    if (ret != FR_OK) return 0.0f;
    
    /* Gesamt-Cluster zählen */
    uint32_t total = fs->n_fatent - 12;  /* FAT32: Cluster ab 12 */
    if (total == 0) return 0.0f;
    
    return (float)(total - free_clusters) / total;
}

/* Frame-Counter als extern (wird vom Writer Task gesetzt) */
extern uint32_t g_v2x_frame_count;

/* Display UI Task */
void v2x_display_ui_task(void *pvParameters)
{
    uint32_t last_count = 0;
    
    ESP_LOGI(TAG, "Display UI Task gestartet");
    
    while (1) {
        /* --- Display löschen (schwarzer Hintergrund) --- */
        v2x_display_clear(DISP_COLOR_BLACK);
        
        /* --- SD-Speicher-Balken (Y=0, Höhe=8px) --- */
        float sd_pct = get_sd_storage_percent();
        v2x_display_storage_bar(0, 0, DISP_W, 8, sd_pct);
        
        /* Text: "SD: ##%" */
        char sd_label[16];
        snprintf(sd_label, sizeof(sd_label), "SD: %3.0f%%", sd_pct * 100);
        v2x_display_text(2, 9, sd_label, DISP_COLOR_WHITE, FONT_6x8);
        
        /* --- Frame-Counter (groß, rot, Y=20) --- */
        uint32_t current_count = g_v2x_frame_count;
        if (current_count != last_count) {
            v2x_display_frame_count(current_count, 28, DISP_W, 40);
            last_count = current_count;
        }
        
        /* --- RSSI-Anzeige (Y=72) --- */
        v2x_display_text(2, 72, "RSSI:", DISP_COLOR_YELLOW, FONT_6x8);
        char rssi_label[20];
        snprintf(rssi_label, sizeof(rssi_label), "Max: %3d dBm", g_v2x_max_rssi);
        v2x_display_text(40, 72, rssi_label, DISP_COLOR_WHITE, FONT_6x8);
        
        /* --- Scroller (Y=84) --- */
        scroller_redraw();
        
        /* --- Statistik-Balken (Y=132) --- */
        v2x_display_text(2, 132, "CH:", DISP_COLOR_GREEN, FONT_6x8);
        
        /* Kanal + Frequenz */
        extern uint32_t g_v2x_current_freq;
        extern int g_v2x_channel_idx;
        char ch_info[20];
        snprintf(ch_info, sizeof(ch_info), "CH:%d %.0fMHz", 
                 g_v2x_channel_idx, g_v2x_current_freq / 1000.0f);
        v2x_display_text(20, 132, ch_info, DISP_COLOR_CYAN, FONT_6x8);
        
        /* BSSID-Farbcodes */
        v2x_display_text(2, 148, "B=BSM C=CAM D=DENM", DISP_COLOR_GRAY, FONT_6x8);
        
        vTaskDelay(pdMS_TO_TICKS(2000));
    }
}