// Package target maps content types to runtime-specific deployment paths.
// The OpenCode target is the thin v2 implementation: a type filter plus
// path mapping, leaving the door open for future targets.
package target

import (
	"os"
	"path/filepath"
	"strings"

	"github.com/m3tam3re/agent-lib/internal/lockfile"
)

// OpenCode maps items into the OpenCode runtime layout, rooted at the
// user's home directory.
type OpenCode struct {
	Home string
}

// NewOpenCode resolves the home directory once for all path mappings.
func NewOpenCode() (*OpenCode, error) {
	home, err := os.UserHomeDir()
	if err != nil {
		return nil, err
	}
	return &OpenCode{Home: home}, nil
}

// DeployPath returns the absolute destination for an item; ok is false for
// types this target never deploys (MCP stays under fleet control).
func (o *OpenCode) DeployPath(typ, name string) (path string, ok bool) {
	switch typ {
	case lockfile.TypeSkill:
		return filepath.Join(o.Home, ".agents", "skills", name), true
	case lockfile.TypeCommand:
		return filepath.Join(o.Home, ".config", "opencode", "commands", name+".md"), true
	case lockfile.TypeAgent:
		return filepath.Join(o.Home, ".config", "opencode", "agents", name+".md"), true
	default:
		return "", false
	}
}

// ScanTargetDirs lists every item currently present in the target dirs,
// keyed "<type>/<name>" — the raw material for detecting unmanaged occupants.
func (o *OpenCode) ScanTargetDirs() map[string]bool {
	out := map[string]bool{}
	skillsDir := filepath.Join(o.Home, ".agents", "skills")
	if entries, err := os.ReadDir(skillsDir); err == nil {
		for _, e := range entries {
			if e.IsDir() {
				out[lockfile.TypeSkill+"/"+e.Name()] = true
			}
		}
	}
	for typ, dir := range map[string]string{
		lockfile.TypeCommand: filepath.Join(o.Home, ".config", "opencode", "commands"),
		lockfile.TypeAgent:   filepath.Join(o.Home, ".config", "opencode", "agents"),
	} {
		entries, err := os.ReadDir(dir)
		if err != nil {
			continue
		}
		for _, e := range entries {
			if !e.IsDir() && strings.HasSuffix(e.Name(), ".md") {
				out[typ+"/"+strings.TrimSuffix(e.Name(), ".md")] = true
			}
		}
	}
	return out
}