function cfg = adaptive_pid_config()
%ADAPTIVE_PID_CONFIG Parameters for the adaptive PID margin study.
% Change target_margin here when a different NCF margin floor is desired.

cfg = struct();
cfg.target_margin = 0.50;
cfg.event_time_s = 10;
cfg.duration_s = 30;
cfg.dt = 1/2048;
cfg.fs = round(1/cfg.dt);
cfg.command_scale = 1.0;
cfg.disturbance_scale = 1.0;
cfg.measurement_noise_fraction = 0.005;
cfg.margin_band_hz = [1.5 120];
cfg.margin_grid_count = 5000;
cfg.penalty_below = 120;
cfg.penalty_peak_shortfall = 40;
cfg.penalty_authority_motion = 3;

cfg.c4_pid = struct('P', 0.15, 'I', 200, 'D', 0.0015, ...
    'derivative_filter_N', 512);

cfg.m91_override = struct( ...
    'threshold', cfg.target_margin, ...
    'band_hz', [2 100], ...
    'df_hz', 1, ...
    'window_s', 5, ...
    'update_interval_s', 0.05, ...
    'segment_s', 512/2048, ...
    'segment_hop_s', 256/2048, ...
    'input_power_range_db', 30, ...
    'gamma_min', 0.47, ...
    'min_bins', 3, ...
    'warm_windows', 5, ...
    'margin_filter_n', 3, ...
    'detect_consecutive', 1, ...
    'calibration_s', 7.5, ...
    'cap', 0.70, ...
    'residual_floor', 0.03, ...
    'residual_prctile', 99, ...
    'residual_early_all_bins', true, ...
    'residual_early_match_hz', 4, ...
    'residual_early_st_floor_frac', 0.80, ...
    'residual_early_st_gate_frac', 0.80, ...
    'st_prctile', 100, ...
    'st_power', 1.15, ...
    'freq_medfilt_n', 3, ...
    'line_reject_hz', [58 62]);
cfg.settled_eval_delay_s = cfg.m91_override.window_s + 3;

cfg.authority_gain = struct('a_min', 0.08, 'a_max', 1.0, ...
    'down_deadband', 0.005, ...
    'down_rate', 0.15, ...
    'down_immediate_margin', 0.38, ...
    'down_confirm_n', 2, ...
    'up_deadband', 0.035, ...
    'power', 1.25, ...
    'smooth_down', 0.85, ...
    'up_rate', 0.0015, ...
    'up_hold_s', 1.0, ...
    'margin_guard_up_rate', 0.025, ...
    'margin_guard_down_rate', 0.025, ...
    'margin_filter_alpha', 0.08);
end