/**
 * Frame-Scroller — rollende Liste der letzten Frames
 * 
 * Zeigt bis zu 7 Frames an, jeder Frame = 1 Zeile (12px hoch):
 *   [RSSI-Balk] X #####-#####-#####  CH:161 RSSI:-45
 * 
 * Der Scroller aktualisiert sich nur wenn sich ein Frame ändert.
 */

#include "esp_log.h"
#include "v2x_display.h"
#include "esp_lcd_panel_ops.h"
#include "freertos/FreeRTOS.h"
#include "freertos/task.h"
#include "freertos/queue.h"

extern esp_lcd_panel_handle_t s_panel;
extern bool s_initialized;

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

/* Scroller-Konfiguration */
#define SCROLLER_FRAMES_VISIBLE    7   /* Frames sichtbar */
#define SCROLLER_LINE_HEIGHT       13  /* Pixel pro Zeile */
#define SCROLLER_START_Y           28  /* Erste Zeile beginnt bei Y=28 */
#define SCROLLER_MAX_ENTRIES       64  /* Frames im Buffer */

/* Frame-Daten für den Scroller */
typedef struct {
    char        msg_char;         /* 'B', 'C', 'D', '?' */
    int8_t      rssi;             /* RSSI dBm */
    uint8_t     ch;               /* Kanal */
    char        bssid_hex[9];     /* #####-#####-##### */
} scroller_entry_t;

static scroller_entry_t s_entries[SCROLLER_MAX_ENTRIES];
static uint32_t s_entry_count = 0;

/* RSSI-Balk als ASCII (20 Zeichen breit) */
static void rssi_to_bar(int8_t rssi, char *bar, int len)
{
    if (rssi <= -100) rssi = -100;
    if (rssi >= -20) rssi = -20;

    float pct = (float)(rssi + 100) / 80.0f;
    int filled = (int)(pct * 20);

    for (int i = 0; i < len - 1; i++) {
        bar[i] = (i < filled) ? '\x5C' : '\xC1';  /* ▌ und ░ (block chars) */
    }
    bar[len - 1] = '\0';
}

/* BSSID als #####-#####-##### hex */
static void bssid_to_str(const uint8_t *bssid, char *str)
{
    snprintf(str, 14, "%02X-%02X-%02X-%02X-%02X-%02X",
             bssid[0], bssid[1], bssid[2], bssid[3], bssid[4], bssid[5]);
}

/* Scroller-Eintrag hinzufügen */
void scroller_add_entry(uint8_t msg_type, int8_t rssi, uint8_t ch, const uint8_t *bssid)
{
    scroller_entry_t *e = &s_entries[s_entry_count % SCROLLER_MAX_ENTRIES];

    /* Msg-Type Character */
    switch (msg_type) {
        case 1: e->msg_char = 'B'; break; /* BSM */
        case 2: e->msg_char = 'C'; break; /* CAM */
        case 3: e->msg_char = 'D'; break; /* DENM */
        default: e->msg_char = '?'; break;
    }

    e->rssi = rssi;
    e->ch = ch;
    if (bssid) {
        bssid_to_str(bssid, e->bssid_hex);
    } else {
        snprintf(e->bssid_hex, 14, "----------");
    }

    s_entry_count++;
}

/* Scroller neu zeichnen (vollständig) */
void scroller_redraw(void)
{
    if (!s_initialized) return;

    int32_t total = s_entry_count;
    int start = (total > SCROLLER_FRAMES_VISIBLE) ? 
                (total - SCROLLER_FRAMES_VISIBLE) : 0;

    /* Hintergrund zeichnen */
    int total_h = SCROLLER_FRAMES_VISIBLE * SCROLLER_LINE_HEIGHT;
    v2x_display_rect(0, SCROLLER_START_Y, DISP_W, total_h, DISP_COLOR_BLACK, true);

    /* Zeilenweise rendern (von oben nach unten = neueste Frames zuerst) */
    for (int i = SCROLLER_FRAMES_VISIBLE - 1; i >= 0; i--) {
        int idx = (start + i) % SCROLLER_MAX_ENTRIES;
        scroller_entry_t *e = &s_entries[idx];
        int y = SCROLLER_START_Y + (SCROLLER_FRAMES_VISIBLE - 1 - i) * SCROLLER_LINE_HEIGHT;

        /* RSSI-Farbbalk links (5px breit, 11px hoch) */
        uint16_t bar_color = DISP_COLOR_RED;
        float pct = (float)(e->rssi + 100) / 80.0f;
        if (pct > 0.6f) bar_color = DISP_COLOR_GREEN;
        else if (pct > 0.3f) bar_color = DISP_COLOR_YELLOW;

        v2x_display_rect(2, y + 1, 5, 11, bar_color, true);

        /* Msg-Type Zeichen (grün/cyan/rot/gray) */
        uint16_t msg_color = DISP_COLOR_GRAY;
        if (e->msg_char == 'B') msg_color = DISP_COLOR_GREEN;
        else if (e->msg_char == 'C') msg_color = DISP_COLOR_CYAN;
        else if (e->msg_char == 'D') msg_color = DISP_COLOR_RED;

        char msg_line[2] = { e->msg_char, '\0' };
        v2x_display_text(9, y + 1, msg_line, msg_color, FONT_6x8);

        /* BSSID als Hex (blau) */
        v2x_display_text(16, y + 1, e->bssid_hex, DISP_COLOR_BLUE, FONT_6x8);

        /* Kanal + RSSI (weiß) */
        char ch_buf[20];
        snprintf(ch_buf, sizeof(ch_buf), "CH:%d %3d", e->ch, e->rssi);
        v2x_display_text(60, y + 1, ch_buf, DISP_COLOR_WHITE, FONT_6x8);
    }
}

/* Geänderte Zeile neu zeichnen (nur die betroffene Zeile — schnell) */
void scroller_redraw_line(uint32_t entry_idx)
{
    if (!s_initialized) return;

    int32_t total = s_entry_count;
    if (entry_idx < (total > SCROLLER_FRAMES_VISIBLE ? total - SCROLLER_FRAMES_VISIBLE : 0)) {
        return; /* Zu alt, nicht sichtbar */
    }

    int start = (total > SCROLLER_FRAMES_VISIBLE) ? 
                (total - SCROLLER_FRAMES_VISIBLE) : 0;
    
    int line_idx = (int)(entry_idx - start);
    if (line_idx < 0 || line_idx >= SCROLLER_FRAMES_VISIBLE) return;

    int idx = entry_idx % SCROLLER_MAX_ENTRIES;
    scroller_entry_t *e = &s_entries[idx];
    int y = SCROLLER_START_Y + (SCROLLER_FRAMES_VISIBLE - 1 - line_idx) * SCROLLER_LINE_HEIGHT;

    /* Zeile löschen */
    v2x_display_rect(0, y, DISP_W, SCROLLER_LINE_HEIGHT, DISP_COLOR_BLACK, true);

    /* Neu zeichnen */
    uint16_t bar_color = DISP_COLOR_RED;
    float pct = (float)(e->rssi + 100) / 80.0f;
    if (pct > 0.6f) bar_color = DISP_COLOR_GREEN;
    else if (pct > 0.3f) bar_color = DISP_COLOR_YELLOW;

    v2x_display_rect(2, y + 1, 5, 11, bar_color, true);

    uint16_t msg_color = DISP_COLOR_GRAY;
    if (e->msg_char == 'B') msg_color = DISP_COLOR_GREEN;
    else if (e->msg_char == 'C') msg_color = DISP_COLOR_CYAN;
    else if (e->msg_char == 'D') msg_color = DISP_COLOR_RED;

    char msg_line[2] = { e->msg_char, '\0' };
    v2x_display_text(9, y + 1, msg_line, msg_color, FONT_6x8);

    v2x_display_text(16, y + 1, e->bssid_hex, DISP_COLOR_BLUE, FONT_6x8);

    char ch_buf[20];
    snprintf(ch_buf, sizeof(ch_buf), "CH:%d %3d", e->ch, e->rssi);
    v2x_display_text(60, y + 1, ch_buf, DISP_COLOR_WHITE, FONT_6x8);
}