package cli

import (
	"fmt"
	"os"
	"path/filepath"

	"github.com/spf13/cobra"
)

var initCmd = &cobra.Command{
	Use:   "init",
	Short: "Initialize at-rund configuration",
	Long:  `Creates ~/.at-rund/ with default configuration and runtime definitions.`,
	RunE:  runInit,
}

func runInit(cmd *cobra.Command, args []string) error {
	dir := configDir()

	// Create directory structure
	dirs := []string{
		dir,
		filepath.Join(dir, "runtimes"),
		filepath.Join(dir, "images"),
		filepath.Join(dir, "bundles"),
		filepath.Join(dir, "keys"),
	}

	for _, d := range dirs {
		if err := os.MkdirAll(d, 0755); err != nil {
			return fmt.Errorf("failed to create %s: %w", d, err)
		}
		fmt.Printf("Created %s\n", d)
	}

	// Write default config
	configPath := filepath.Join(dir, "config.toml")
	if _, err := os.Stat(configPath); os.IsNotExist(err) {
		if err := os.WriteFile(configPath, []byte(defaultConfig), 0644); err != nil {
			return fmt.Errorf("failed to write config: %w", err)
		}
		fmt.Printf("Created %s\n", configPath)
	} else {
		fmt.Printf("Skipped %s (already exists)\n", configPath)
	}

	// Write default runtime configs
	runtimes := map[string]string{
		"deno.nix":   denoRuntime,
		"node.nix":   nodeRuntime,
		"python.nix": pythonRuntime,
	}

	for name, content := range runtimes {
		path := filepath.Join(dir, "runtimes", name)
		if _, err := os.Stat(path); os.IsNotExist(err) {
			if err := os.WriteFile(path, []byte(content), 0644); err != nil {
				return fmt.Errorf("failed to write %s: %w", name, err)
			}
			fmt.Printf("Created %s\n", path)
		} else {
			fmt.Printf("Skipped %s (already exists)\n", path)
		}
	}

	fmt.Println("\nInitialized at-rund. Next steps:")
	fmt.Println("  1. Edit ~/.at-rund/config.toml to set your DID")
	fmt.Println("  2. Run 'at-rund build' to build runtime images")
	fmt.Println("  3. Run 'at-rund serve' to start the server")

	return nil
}

var defaultConfig = `# at-rund configuration
#
# Your runner represents YOU on the network. Bundle authors trust your runner
# because they trust you. Configure it to reflect your identity and policies.

# Your identity (the runner IS you)
# did = "did:plc:your-did-here"
# handle = "you.bsky.social"

# Server settings
port = 3000
dev_mode = false

[pool]
# VMs to keep warm per runtime (prod mode only)
pre_warm = 2
# Maximum total VMs across all runtimes
max_vms = 20
# Reclaim idle VMs after this duration
idle_timeout = "5m"
# Maximum time to wait for VM boot
spawn_timeout = "30s"

[runtimes]
# Runtime name = path to .nix file (relative to ~/.at-rund/runtimes/)
# Write your own configs or use the examples as a starting point
deno = "deno.nix"
# node = "node.nix"
# python = "python.nix"

[access]
# Access control mode: "open", "allowlist", or "blocklist"
mode = "open"

# If mode = "allowlist", only these DIDs can run bundles
# allowlist = ["did:plc:friend1", "did:plc:friend2"]

# If mode = "blocklist", block specific DIDs
# blocklist = ["did:plc:spammer"]

[limits]
# Per-request resource limits
max_execution_time = "30s"
max_memory_mb = 512

[observability]
# OpenTelemetry endpoint for metrics/traces
# otlp_endpoint = "http://localhost:4317"

# Log format: "json" or "text"
log_format = "text"
`

var denoRuntime = `# Deno runtime configuration
{ pkgs, ... }:
{
  mimeTypes = [
    "application/javascript+deno"
    "application/javascript+deno-atrun"
    "application/typescript+deno"
  ];

  guest = {
    environment.systemPackages = with pkgs; [
      deno
    ];
  };

  executor = {
    command = "deno run";
    permissionFlags = {
      net = "--allow-net";
      read = "--allow-read";
      write = "--allow-write";
      env = "--allow-env";
    };
  };
}
`

var nodeRuntime = `# Node.js runtime configuration
{ pkgs, ... }:
{
  mimeTypes = [
    "application/javascript+node"
    "application/javascript"
  ];

  guest = {
    environment.systemPackages = with pkgs; [
      nodejs_22
    ];
  };

  executor = {
    command = "node";
    permissionFlags = {};  # Node doesn't have permission flags
  };
}
`

var pythonRuntime = `# Python runtime configuration
{ pkgs, ... }:
{
  mimeTypes = [
    "application/python"
    "application/x-python"
  ];

  guest = {
    environment.systemPackages = with pkgs; [
      python312
      python312Packages.pip
    ];
  };

  executor = {
    command = "python3";
    permissionFlags = {};
  };
}
`