package paths

import (
	`io/fs`
	`os`
	`path/filepath`
	`time`

	`github.com/djherbis/times`
	`r00t2.io/goutils/bitmask`
)

/*
	Match returns match (a  ptr to a FsSearchResult if the specified path matches, otherwise nil),
	miss (ptr the specified path does not match, otherwise nil), and an fs.DirEntry and fs.FileInfo
	for path. d and/or fi may be nil.

	If err is not nil, it represents an unexpected error and as such, both match and miss should be nil.

	Match, miss, and err will all be nil if the filesystem object/path does not exist.
*/
func (f *FsSearchCriteria) Match(path string, d fs.DirEntry, fi fs.FileInfo) (match, miss *FsSearchResult, err error) {

	var typeMode fs.FileMode
	var m FsSearchResult
	var typeFilter *bitmask.MaskBit = bitmask.NewMaskBitExplicit(uint(f.TargetType))

	m = FsSearchResult{
		Path:     path,
		DirEntry: d,
		FileInfo: fi,
		Criteria: f,
	}

	if f == nil {
		return
	}

	// A DirEntry can be created from a FileInfo but not vice versa.
	if m.FileInfo == nil {
		if m.DirEntry != nil {
			if m.FileInfo, err = m.DirEntry.Info(); err != nil {
				err = filterNoFileDir(err)
				if err != nil {
					return
				}
			}
		} else {
			if f.FollowSymlinks {
				if m.FileInfo, err = os.Stat(path); err != nil {
					err = filterNoFileDir(err)
					if err != nil {
						return
					}
				}
			} else {
				if m.FileInfo, err = os.Lstat(path); err != nil {
					err = filterNoFileDir(err)
					if err != nil {
						return
					}
				}
			}
			m.DirEntry = fs.FileInfoToDirEntry(m.FileInfo)
		}
	}
	if m.DirEntry == nil {
		m.DirEntry = fs.FileInfoToDirEntry(m.FileInfo)
	}
	if m.DirEntry == nil || m.FileInfo == nil {
		m.MissReason = MissNoMeta
		miss = &m
		return
	}

	if m.Times, err = times.Stat(path); err != nil {
		err = filterNoFileDir(err)
		if err != nil {
			return
		}
	}

	if f.PathPtrn != nil && !f.PathPtrn.MatchString(path) {
		m.MissReason = MissBadPath
		miss = &m
		return
	}
	if f.BasePtrn != nil && !f.BasePtrn.MatchString(filepath.Base(path)) {
		m.MissReason = MissBadBase
		miss = &m
		return
	}

	// age
	if f.Age != nil {
		if f.Now == nil {
			f.Now = new(time.Time)
			*f.Now = time.Now()
		}
		if !filterTimes(m.Times, f.Age, &f.AgeType, f.OlderThan, f.Now) {
			m.MissReason = MissBadTime
			miss = &m
			return
		}
	}

	// fs object type (file, dir, etc.)
	typeMode = m.FileInfo.Mode().Type()
	if typeMode == 0 && f.NoFiles {
		m.MissReason = MissFile
		miss = &m
		return
	} else if typeMode != 0 {
		if !typeFilter.HasFlag(bitmask.MaskBit(typeMode)) {
			m.MissReason = MissType
			miss = &m
			return
		}
	}

	// If it gets to here, it matches.
	match = &m

	return
}