package resolver

import (
	"cliprepo/internal/tree"
	"os"
	"path/filepath"
)

type Resolver struct {
	root string
	seen map[string]struct{}
}

func New(root string) *Resolver {
	return &Resolver{
		root: root,
		seen: make(map[string]struct{}),
	}
}

// WalkAll 遍历所有文件，并自动跳过 .git 和 .gitignore 中的文件
func (r *Resolver) WalkAll() ([]string, error) {
	var result []string
	ig, _ := tree.Load(r.root)

	err := filepath.Walk(r.root, func(path string, info os.FileInfo, err error) error {
		if err != nil {
			return nil
		}

		// 显式跳过 .git 目录
		if info.IsDir() && info.Name() == ".git" {
			return filepath.SkipDir
		}

		rel, _ := filepath.Rel(r.root, path)

		// 遵循 .gitignore 规则
		if ig != nil && ig.MatchesPath(rel) {
			if info.IsDir() {
				return filepath.SkipDir
			}
			return nil
		}

		if info.IsDir() {
			return nil
		}

		r.add(rel, &result)
		return nil
	})

	return result, err
}

func (r *Resolver) AddFile(path string, result *[]string) {
	r.add(path, result)
}

func (r *Resolver) add(path string, result *[]string) {
	if _, ok := r.seen[path]; ok {
		return
	}
	r.seen[path] = struct{}{}
	*result = append(*result, path)
}

// Unique 保留此方法供 run.go 调用
func (r *Resolver) Unique(in []string) []string {
	seen := make(map[string]struct{})
	out := make([]string, 0, len(in))

	for _, f := range in {
		if _, ok := seen[f]; ok {
			continue
		}
		seen[f] = struct{}{}
		out = append(out, f)
	}

	return out
}