{ config, pkgs, lib, ... }:

let
  cfg = config.services.opencode;
in {
  options.services.opencode = {
    enable = lib.mkEnableOption "OpenCode AI Service";
    port = lib.mkOption {
      type = lib.types.port;
      default = 4099;
    };
    ollamaUrl = lib.mkOption {
      type = lib.types.str;
      default = "http://127.0.0.1:11434/v1"; 
    };
  };

  config = lib.mkIf cfg.enable {
    programs.nix-ld.enable = true;

    # We inject the Context7 MCP requirement directly into your nix-generated config
    environment.etc."opencode/opencode.json".text = builtins.toJSON {
      "$schema" = "https://opencode.ai/config.json";
      "model" = "devstral-2-small-llama_cpp";
      
      # Added the MCP section required by GSD
      "mcp" = {
        "context7" = {
          "type" = "remote";
          "url" = "https://mcp.context7.com/mcp";
        };
      };

      "provider" = {
        "llamacpp" = {
          "name" = "Llama.cpp (Local MI50)";
          "npm" = "@ai-sdk/openai-compatible";
          "options" = {
            "baseURL" = "http://localhost:8300/v1";
            "apiKey" = "not-needed";
          };
          "models" = {
            "devstral-2-small-llama_cpp" = {
              "name" = "Devstral 2 small 24B Q8 (llama.cpp)";
              "tools" = true;
              "reasoning" = false;
            };
          };
        };
        "ollama" = {
          "name" = "Ollama (Local)";
          "npm" = "@ai-sdk/openai-compatible";
          "options" = {
            "baseURL" = cfg.ollamaUrl;
            "headers" = { "Content-Type" = "application/json"; };
          };
          "models" = {
            "devstral-small-2:24b-128k" = {
              "name" = "Mistral Devstral Small 2 (Ollama)";
              "tools" = true;
              "reasoning" = false;
            };
          };
        };
      };
    };

    # This service runs the GSD installer directly from the source
    systemd.services.opencode-gsd-install = {
      description = "Install Get Shit Done OpenCode Components";
      after = [ "network-online.target" ];
      wantedBy = [ "multi-user.target" ];
      path = with pkgs; [ 
        nodejs
        git
        coreutils 
        bash
      ];
      serviceConfig = {
        Type = "oneshot";
        User = "gortium";
        RemainAfterExit = true;
        Environment = [
          "HOME=/home/gortium"
          "SHELL=${pkgs.bash}/bin/bash"
          "PATH=${lib.makeBinPath [ pkgs.nodejs pkgs.git pkgs.bash pkgs.coreutils ]}"
        ];
      };
      script = ''
        # Check if the GSD directory exists
  if [ ! -d "/home/gortium/.config/opencode/gsd" ]; then
    echo "GSD not found. Installing..."
    ${pkgs.nodejs}/bin/npx -y github:dbachelder/get-shit-done-opencode --global --force
  else
    echo "GSD already installed. Skipping auto-reinstall."
    echo "To force update, run: sudo systemctl restart opencode-gsd-install.service"
  fi
      '';
    };

    systemd.services.opencode = {
      description = "OpenCode AI Coding Agent Server";
      after = [ "network.target" "ai_stack.service" "opencode-gsd-install.service" ];
      requires = [ "ai_stack.service" "opencode-gsd-install.service" ];
      wantedBy = [ "multi-user.target" ];

      path = with pkgs; [
        bash
        coreutils
        nodejs
        git
        nix
        ripgrep
        fd
      ];

      serviceConfig = {
        Type = "simple";
        User = "gortium";
        WorkingDirectory = "/home/gortium/infra";
        ExecStart = "${pkgs.nodejs}/bin/npx -y opencode-ai serve --hostname 0.0.0.0 --port ${toString cfg.port}";
        Restart = "on-failure";
      };

      environment = {
        OLLAMA_BASE_URL = "http://127.0.0.1:11434";
        # Important: GSD looks at ~/.config/opencode, so we ensure the server sees our /etc config
        OPENCODE_CONFIG = "/etc/opencode/opencode.json";
        HOME = "/home/gortium";
      };
    };

    networking.firewall.allowedTCPPorts = [ cfg.port ];
  };
}