package com.guinetik.hexafun.examples.sysmon;
   
   import static com.guinetik.hexafun.examples.sysmon.SysmonKeys.*;
   import static com.guinetik.hexafun.examples.tui.Ansi.*;
   
   import com.guinetik.hexafun.examples.tui.View;
   
   /**
    * Responsive view components for the System Monitor TUI.
   *
   * <p>All views use {@code state.width()} to render at the current terminal width.
   * Width is recalculated on each refresh.</p>
   */
  public final class SysmonView {
  
      private SysmonView() {}
  
      private static final int PADDING = 4; // Left/right padding
  
      /**
       * Compose the full screen view.
       */
      public static View<SysmonState> screen() {
          return clear()
              .andThen(header())
              .andThen(metrics())
              .andThen(menu())
              .andThen(status())
              .andThen(prompt());
      }
  
      /**
       * Clear screen and reset cursor.
       */
      public static View<SysmonState> clear() {
          return state -> CLEAR + CURSOR_HOME;
      }
  
      /**
       * Render the header box - responsive to terminal width.
       */
      public static View<SysmonState> header() {
          return state -> {
              int boxWidth = state.width() - PADDING;
              int innerWidth = boxWidth - 2;
  
              return lines(
                  "",
                  color("  " + DBOX_TOP_LEFT + repeat(DBOX_HORIZONTAL, innerWidth) + DBOX_TOP_RIGHT, CYAN),
                  color("  " + DBOX_VERTICAL, CYAN) +
                      color(center("SYSTEM MONITOR", innerWidth), BOLD, BRIGHT_WHITE) +
                      color(DBOX_VERTICAL, CYAN),
                  color("  " + DBOX_VERTICAL, CYAN) +
                      color(center("HexaFun Adapter Demo", innerWidth), DIM) +
                      color(DBOX_VERTICAL, CYAN),
                  color("  " + DBOX_BOTTOM_LEFT + repeat(DBOX_HORIZONTAL, innerWidth) + DBOX_BOTTOM_RIGHT, CYAN),
                  ""
              );
          };
      }
  
      /**
       * Render the metrics output based on selected format - responsive.
       */
      public static View<SysmonState> metrics() {
          return state -> {
              SystemMetrics m = state.metrics();
              int boxWidth = state.width() - PADDING;
  
              String output = switch (state.format()) {
                  case TUI -> renderTuiGauges(m, boxWidth);
                  case CLI -> formatBox("CLI Output", state.app().adapt(TO_CLI, m), boxWidth, GREEN);
                  case JSON -> formatBox("JSON Output", state.app().adapt(TO_JSON, m), boxWidth, YELLOW);
                  case PROMETHEUS -> formatBox("Prometheus Output", state.app().adapt(TO_PROMETHEUS, m), boxWidth, MAGENTA);
              };
              return output + "\n";
          };
      }
  
      /**
       * Render TUI gauges - responsive bar width.
       */
      private static String renderTuiGauges(SystemMetrics metrics, int boxWidth) {
          StringBuilder sb = new StringBuilder();
          int innerWidth = boxWidth - 2;
          // Gauge content: space(1) + label(4) + space(1) + bracket(1) + bar + bracket(1) + percent(5) + warn(2) + space(1) = 16 fixed
          int barWidth = innerWidth - 16;
  
          String title = "─ System Monitor ";  // 17 chars
  
          // Header
          sb.append(color("  " + BOX_TOP_LEFT + title +
              repeat(BOX_HORIZONTAL, innerWidth - title.length()) + BOX_TOP_RIGHT, CYAN)).append("\n");
  
          // CPU gauge
          sb.append(color("  " + BOX_VERTICAL, CYAN))
            .append(gauge("CPU ", metrics.cpu(), metrics.cpuWarning(), barWidth))
            .append(color(BOX_VERTICAL, CYAN)).append("\n");
  
         // Memory gauge
         sb.append(color("  " + BOX_VERTICAL, CYAN))
           .append(gauge("MEM ", metrics.memory(), metrics.memoryWarning(), barWidth))
           .append(color(BOX_VERTICAL, CYAN)).append("\n");
 
         // Disk gauge
         sb.append(color("  " + BOX_VERTICAL, CYAN))
           .append(gauge("DISK", metrics.disk(), metrics.diskWarning(), barWidth))
           .append(color(BOX_VERTICAL, CYAN)).append("\n");
 
         // Footer
         sb.append(color("  " + BOX_BOTTOM_LEFT + repeat(BOX_HORIZONTAL, innerWidth) +
             BOX_BOTTOM_RIGHT, CYAN)).append("\n");
 
         return sb.toString();
     }
 
     /**
      * Build a single gauge line with color-coded bar.
      */
     private static String gauge(String label, double percent, boolean warning, int barWidth) {
         int filled = (int) ((barWidth * percent) / 100);
         int empty = barWidth - filled;
 
         String barColor = warning ? RED : GREEN;
         String warnIcon = warning ? color(" ⚠", YELLOW) : "  ";
 
         return " " + color(label, BOLD) + " " +
             color("[", DIM) +
             color(repeat(BLOCK_FULL, filled), barColor) +
             color(repeat(BLOCK_LIGHT, empty), BRIGHT_BLACK) +
             color("]", DIM) +
             color(String.format(" %3.0f%%", percent), warning ? RED : WHITE) +
             warnIcon + " ";
     }
 
     /**
      * Format content in a responsive box with title.
      */
     private static String formatBox(String title, String content, int boxWidth, String borderColor) {
         StringBuilder sb = new StringBuilder();
         int innerWidth = boxWidth - 2;
         String titlePrefix = "─ " + title + " ";  // Calculate actual length
 
         // Top border with title
         sb.append(color("  " + BOX_TOP_LEFT + titlePrefix +
             repeat(BOX_HORIZONTAL, innerWidth - titlePrefix.length()) + BOX_TOP_RIGHT, borderColor))
           .append("\n");
 
         // Content lines: border(1) + space(1) + content + space(1) + border(1) = boxWidth
         // So content width = boxWidth - 4 = innerWidth - 2
         int contentWidth = innerWidth - 2;
         for (String line : content.split("\n")) {
             if (!line.isEmpty()) {
                 String truncated = line.length() > contentWidth
                     ? line.substring(0, Math.max(0, contentWidth - 3)) + "..."
                     : line;
                 sb.append(color("  " + BOX_VERTICAL, borderColor))
                   .append(" ")
                   .append(pad(truncated, contentWidth))
                   .append(" ")
                   .append(color(BOX_VERTICAL, borderColor))
                   .append("\n");
             }
         }
 
         // Bottom border
         sb.append(color("  " + BOX_BOTTOM_LEFT + repeat(BOX_HORIZONTAL, innerWidth) +
             BOX_BOTTOM_RIGHT, borderColor))
           .append("\n");
 
         return sb.toString();
     }
 
     /**
      * Render the format selection menu.
      */
     public static View<SysmonState> menu() {
         return state -> {
             int boxWidth = state.width() - PADDING;
             StringBuilder sb = new StringBuilder();
 
             sb.append(color("  " + repeat(BOX_HORIZONTAL, boxWidth), DIM))
               .append("\n\n");
 
             // Format options
             sb.append("  ");
             int i = 1;
             for (SysmonFormat f : SysmonFormat.values()) {
                 String sel = f == state.format() ? "●" : "○";
                 sb.append(color("[" + i + "]", f.color, BOLD));
                 sb.append(
                     color(
                         " " + sel + " " + f.label + "  ",
                         f == state.format() ? f.color : BRIGHT_BLACK
                     )
                 );
                 i++;
             }
             sb.append("\n\n");
 
             // Other options
             sb.append("  ");
             sb.append(color("[r]", YELLOW, BOLD))
               .append(color(" Refresh  ", YELLOW));
             sb.append(color("[q]", BRIGHT_BLACK, BOLD))
               .append(color(" Quit", BRIGHT_BLACK));
             sb.append("\n\n");
 
             return sb.toString();
         };
     }
 
     /**
      * Render status message.
      */
     public static View<SysmonState> status() {
         return state ->
             state.status().isEmpty()
                 ? "\n"
                 : color(
                       "  " + ARROW_RIGHT + " " + state.status(),
                       state.statusColor()
                   ) +
                   "\n\n";
     }
 
     /**
      * Render input prompt.
      */
     public static View<SysmonState> prompt() {
         return state -> color("  > ", CYAN, BOLD);
     }
 }