package toolsrv

import (
	"context"
	"fmt"
)

// Process represents a running toolsrv subprocess.
// The session owns this and calls Close() when the session ends.
type Process struct {
	// Socket is the Unix socket path clients should Dial().
	Socket string
	// Info holds host environment details (platform, git repo status).
	Info HostInfo
	// cleanup shuts down the subprocess and removes the socket.
	cleanup func()
}

// Close shuts down the toolsrv subprocess and removes the socket file.
func (p *Process) Close() {
	if p.cleanup != nil {
		p.cleanup()
	}
}

// Spawn starts a local ollie-remote subprocess listening on a Unix socket.
// The returned Process owns the subprocess lifecycle. Callers connect
// via Dial(LocalAddr(proc.Socket)).
func Spawn(ctx context.Context, cwd string, opts ...Option) (*Process, error) {
	StreamOutput(ctx, "[toolsrv] spawning local toolsrv...\n")

	t, err := localDial(ctx, cwd, opts...)
	if err != nil {
		return nil, err
	}

	// Verify the server is responsive via the initial connection.
	conn := NewConnSplit(t.r, t.w, func() {})
	var info HostInfo
	if hi, err := conn.FetchHostInfo(); err == nil {
		info = hi
	}

	StreamOutput(ctx, fmt.Sprintf("[toolsrv] local ready: %s (socket %s)\n", cwd, t.sockPath))

	return &Process{
		Socket:  t.sockPath,
		Info:    info,
		cleanup: t.cleanup,
	}, nil
}

// SpawnRemote starts ollie-remote on a remote host via SSH, sets up Unix
// socket forwarding, and returns a Process with the local forwarded socket.
func SpawnRemote(ctx context.Context, cfg RemoteConfig) (*Process, error) {
	StreamOutput(ctx, fmt.Sprintf("[toolsrv] dialing %s (cwd: %s)...\n", cfg.SSHTarget, cfg.CWD))

	t, err := sshDial(ctx, cfg)
	if err != nil {
		return nil, fmt.Errorf("spawn remote: %w", err)
	}

	conn := NewConnSplit(t.r, t.w, func() {})
	var info HostInfo
	if hi, err := conn.FetchHostInfo(); err == nil {
		info = hi
	}

	StreamOutput(ctx, fmt.Sprintf("[toolsrv] remote ready: %s → %s (%s/%s)\n", cfg.SSHTarget, t.sockPath, info.Platform, info.Arch))

	return &Process{
		Socket:  t.sockPath,
		Info:    info,
		cleanup: t.cleanup,
	}, nil
}