package filter

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

	"dirmd/internal/config"
)

type Filter struct {
	MaxSize      int64
	Extensions   []string
	Ignores      []string
	OmitTest     bool
	FrontendOnly bool
}

func (f *Filter) ShouldSkipDir(name string) bool {
	if strings.HasPrefix(name, ".") {
		return true
	}
	for _, pattern := range f.Ignores {
		matched, _ := filepath.Match(pattern, name)
		if matched {
			return true
		}
	}
	return false
}

func (f *Filter) ShouldSkipFile(path, name string, info os.FileInfo) bool {
	if strings.HasPrefix(name, ".") {
		return true
	}

	for _, pattern := range f.Ignores {
		matched, _ := filepath.Match(pattern, name)
		if matched {
			return true
		}
	}

	if info.Size() > f.MaxSize {
		return true
	}

	if f.FrontendOnly && !isFrontendOrReadme(path, name) {
		return true
	}

	if f.OmitTest && isTestFile(path, name) {
		return true
	}

	ext := filepath.Ext(path)
	for _, bad := range f.Extensions {
		if strings.EqualFold(ext, bad) {
			return true
		}
	}

	return false
}

func isFrontendOrReadme(path, name string) bool {
	ext := strings.ToLower(filepath.Ext(path))
	for _, fe := range config.FrontendExts {
		if strings.EqualFold(ext, fe) {
			return true
		}
	}
	return strings.EqualFold(name, "README.md")
}

func isTestFile(path, name string) bool {
	ext := strings.ToLower(filepath.Ext(path))

	switch ext {
	case ".go":
		return strings.HasSuffix(strings.ToLower(name), "_test.go")
	case ".java":
		base := strings.TrimSuffix(name, filepath.Ext(name))
		if strings.HasSuffix(base, "Test") || strings.HasSuffix(base, "Tests") {
			return true
		}
		slashPath := filepath.ToSlash(path)
		return strings.Contains(slashPath, "/src/test/")
	}

	return false
}

func IsSymlink(path string) bool {
	info, err := os.Lstat(path)
	if err != nil {
		return false
	}
	return info.Mode()&os.ModeSymlink != 0
}