{ pkgs, ... }:
{
  # Install the community Anker Solix integration (thomluther)
  # TODO: migrate to official local Modbus integration once E2700 Pro is supported
  systemd.services.install-anker-solix = {
    description = "Install Anker Solix Integration";
    wantedBy = [ "multi-user.target" ];
    after = [ "network-online.target" ];
    wants = [ "network-online.target" ];
    serviceConfig = {
      Type = "oneshot";
    };
    script = ''
      set -e
      VERSION="3.5.4"
      DIR="/var/lib/hass/custom_components/anker_solix"
      mkdir -p "$DIR"
      ${pkgs.curl}/bin/curl -fL --retry 3 --retry-delay 5 "https://github.com/thomluther/ha-anker-solix/releases/download/$VERSION/anker_solix.zip" -o /tmp/anker_solix.zip
      ${pkgs.unzip}/bin/unzip -o /tmp/anker_solix.zip -d "$DIR"
      rm /tmp/anker_solix.zip
      chown -R hass:hass "$DIR"
    '';
  };

  services.home-assistant.extraComponents = [
    "integration"
  ];

  services.home-assistant.config = {
    # Riemann sum integration sensors to convert W → kWh for the energy dashboard
    sensor = [
      {
        platform = "integration";
        source = "sensor.solarbank_3_e2700_pro_solar_power";
        name = "Solarbank Solar Energy";
        unit_prefix = "k";
        round = 2;
        method = "left";
      }
      {
        platform = "integration";
        source = "sensor.solarbank_3_e2700_pro_charge_power";
        name = "Solarbank Charge Energy";
        unit_prefix = "k";
        round = 2;
        method = "left";
      }
      {
        platform = "integration";
        source = "sensor.solarbank_3_e2700_pro_discharge_power";
        name = "Solarbank Discharge Energy";
        unit_prefix = "k";
        round = 2;
        method = "left";
      }
    ];
    # Dashboard helper: shows current target output, allows manual override
    input_number.solarbank_target_output = {
      name = "Solarbank Target Output";
      min = 0;
      max = 800;
      step = 10;
      unit_of_measurement = "W";
      icon = "mdi:solar-power";
    };

    # Zero-export grid balancing automation
    # Adjusts Solarbank output every 30s to drive grid import on phase C toward 0W
    "automation solarbank zero export" = {
      alias = "Solarbank Zero Export";
      mode = "single";
      trigger = {
        platform = "state";
        entity_id = "sensor.shellyem3_485519d792a7_channel_c_power";
      };
      condition = [
        {
          condition = "not";
          conditions = [
            {
              condition = "state";
              entity_id = "number.solarbank_3_e2700_pro_system_output_preset";
              state = "unavailable";
            }
          ];
        }
        {
          condition = "not";
          conditions = [
            {
              condition = "state";
              entity_id = "number.solarbank_3_e2700_pro_system_output_preset";
              state = "unknown";
            }
          ];
        }
      ];
      action = [
        {
          variables = {
            grid_power = "{{ states('sensor.shellyem3_485519d792a7_channel_c_power') | float(0) }}";
            current_output = "{{ states('number.solarbank_3_e2700_pro_system_output_preset') | float(0) }}";
          };
        }
        {
          variables = {
            desired_output = "{{ [([current_output + grid_power, 0] | max), 800] | min }}";
            rounded_output = "{{ (desired_output / 10) | round(0) * 10 }}";
          };
        }
        {
          choose = [
            {
              conditions = [
                "{{ (rounded_output - current_output) | abs >= 10 }}"
              ];
              sequence = [
                {
                  service = "input_number.set_value";
                  target.entity_id = "input_number.solarbank_target_output";
                  data.value = "{{ rounded_output }}";
                }
                {
                  service = "number.set_value";
                  target.entity_id = "number.solarbank_3_e2700_pro_system_output_preset";
                  data.value = "{{ rounded_output }}";
                }
              ];
            }
          ];
        }
      ];
    };
  };
}