package zoopb

// this is becoming a standard format
// todo: autogenerate this from the .proto file?

import (
	"fmt"
	"os"
	"sort"
	sync "sync"
	"time"

	timestamppb "google.golang.org/protobuf/types/known/timestamppb"
)

// bad global lock until I figure out some other plan
var lock sync.RWMutex

type PackageIterator struct {
	sync.RWMutex

	packs []*Package
	index int
}

// NewPackageIterator initializes a new iterator.
func NewPackageIterator(packs []*Package) *PackageIterator {
	return &PackageIterator{packs: packs}
}

// Scan moves to the next element and returns false if there are no more packs.
func (it *PackageIterator) Scan() bool {
	if it.index >= len(it.packs) {
		return false
	}
	it.index++
	return true
}

// Package returns the current repo.
func (it *PackageIterator) Package() *Package {
	if it.packs[it.index-1] == nil {
		for i, d := range it.packs {
			fmt.Println("i =", i, d)
		}
		fmt.Println("len =", len(it.packs))
		fmt.Println("repo == nil", it.index, it.index-1)
		os.Exit(-1)
	}
	return it.packs[it.index-1]
}

// Use Scan() in a loop, similar to a while loop
//
//	for iterator.Scan() {
//		d := iterator.Package()
//		fmt.Println("Package UUID:", d.Uuid)
//	}

func (r *Packages) All() *PackageIterator {
	repoPointers := r.selectAllPackages()

	iterator := NewPackageIterator(repoPointers)
	return iterator
}

func (r *Packages) SortByName() *PackageIterator {
	packs := r.selectAllPackages()

	sort.Sort(ByName(packs))

	iterator := NewPackageIterator(packs)
	return iterator
}

// enforces no duplicate package names
func (r *Packages) Append(newP *Package) bool {
	lock.Lock()
	defer lock.Unlock()

	for _, p := range r.Packages {
		if p.Name == newP.Name {
			return false
		}
	}

	r.Packages = append(r.Packages, newP)
	return true
}

// Update version and timestamp.
// returns ok (ok == true if not found)
func (r *Packages) Update(newP *Package) bool {
	lock.Lock()
	defer lock.Unlock()

	var found *Package
	for _, p := range r.Packages {
		if p.Name == newP.Name {
			found = p
		}
	}
	if found == nil {
		// r.Append(newP) // update here?
		return true
	}

	var changed bool = false
	if newP.Version != found.Version {
		changed = true
		found.Version = newP.Version
	}

	now := time.Now()
	found.Laststamp = timestamppb.New(now)
	return changed
}

// returns time.Duration since last Update()
func (r *Package) Age(newP *Package) time.Duration {
	t := time.Since(r.Laststamp.AsTime())
	return t
}

// find a package by name
func (r *Packages) FindByName(name string) *Package {
	lock.RLock()
	defer lock.RUnlock()

	for _, p := range r.Packages {
		if p.Name == name {
			return p
		}
	}

	return nil
}

func (r *Packages) Len() int {
	lock.RLock()
	defer lock.RUnlock()

	return len(r.Packages)
}

type ByName []*Package

func (a ByName) Len() int           { return len(a) }
func (a ByName) Less(i, j int) bool { return a[i].Name < a[j].Name }
func (a ByName) Swap(i, j int)      { a[i], a[j] = a[j], a[i] }

// safely returns a slice of pointers to the Package protobufs
func (r *Packages) selectAllPackages() []*Package {
	lock.RLock()
	defer lock.RUnlock()

	// Create a new slice to hold pointers to each Package
	var allPacks []*Package
	allPacks = make([]*Package, len(r.Packages))
	for i, p := range r.Packages {
		allPacks[i] = p // Copy pointers for safe iteration
	}

	return allPacks
}

/*
func (r *Packages) UnmergedPackageRepos() *PackageRepoIterator {
	repoPointers := r.selectUnmergedPackageRepos()

	sort.Sort(ByName(repoPointers))

	iterator := NewPackageRepoIterator(repoPointers)

	return iterator
}
*/

/*
// this sort doesn't really work. I think it forgets to sort the last two
// todo: sort this out. literally
// SelectPackagePointers safely returns a slice of pointers to Package records.
func (r *Packages) selectUnmergedPackages() []*PackageRow {
	r.RLock()
	defer r.RUnlock()

	// Create a new slice to hold pointers to each Package
	// repoPointers := make([]*Package, len(c.E.Packages))
	var repoPointers []*PackageRow
	for _, repo := range me.allrepos {
		repoPointers = append(repoPointers, repo) // Copy pointers for safe iteration
	}

	return repoPointers
}
*/