package session

import (
	"sort"

	"github.com/containrrr/watchtower/pkg/types"
)

type report struct {
	scanned []types.ContainerReport
	updated []types.ContainerReport
	failed  []types.ContainerReport
	skipped []types.ContainerReport
	stale   []types.ContainerReport
	fresh   []types.ContainerReport
}

func (r *report) Scanned() []types.ContainerReport {
	return r.scanned
}
func (r *report) Updated() []types.ContainerReport {
	return r.updated
}
func (r *report) Failed() []types.ContainerReport {
	return r.failed
}
func (r *report) Skipped() []types.ContainerReport {
	return r.skipped
}
func (r *report) Stale() []types.ContainerReport {
	return r.stale
}
func (r *report) Fresh() []types.ContainerReport {
	return r.fresh
}
func (r *report) All() []types.ContainerReport {
	allLen := len(r.scanned) + len(r.updated) + len(r.failed) + len(r.skipped) + len(r.stale) + len(r.fresh)
	all := make([]types.ContainerReport, 0, allLen)

	presentIds := map[types.ContainerID][]string{}

	appendUnique := func(reports []types.ContainerReport) {
		for _, cr := range reports {
			if _, found := presentIds[cr.ID()]; found {
				continue
			}
			all = append(all, cr)
			presentIds[cr.ID()] = nil
		}
	}

	appendUnique(r.updated)
	appendUnique(r.failed)
	appendUnique(r.skipped)
	appendUnique(r.stale)
	appendUnique(r.fresh)
	appendUnique(r.scanned)

	sort.Sort(sortableContainers(all))

	return all
}

// NewReport creates a types.Report from the supplied Progress
func NewReport(progress Progress) types.Report {
	report := &report{
		scanned: []types.ContainerReport{},
		updated: []types.ContainerReport{},
		failed:  []types.ContainerReport{},
		skipped: []types.ContainerReport{},
		stale:   []types.ContainerReport{},
		fresh:   []types.ContainerReport{},
	}

	for _, update := range progress {
		if update.state == SkippedState {
			report.skipped = append(report.skipped, update)
			continue
		}

		report.scanned = append(report.scanned, update)
		if update.newImage == update.oldImage {
			update.state = FreshState
			report.fresh = append(report.fresh, update)
			continue
		}

		switch update.state {
		case UpdatedState:
			report.updated = append(report.updated, update)
		case FailedState:
			report.failed = append(report.failed, update)
		default:
			update.state = StaleState
			report.stale = append(report.stale, update)
		}
	}

	sort.Sort(sortableContainers(report.scanned))
	sort.Sort(sortableContainers(report.updated))
	sort.Sort(sortableContainers(report.failed))
	sort.Sort(sortableContainers(report.skipped))
	sort.Sort(sortableContainers(report.stale))
	sort.Sort(sortableContainers(report.fresh))

	return report
}

type sortableContainers []types.ContainerReport

// Len implements sort.Interface.Len
func (s sortableContainers) Len() int { return len(s) }

// Less implements sort.Interface.Less
func (s sortableContainers) Less(i, j int) bool { return s[i].ID() < s[j].ID() }

// Swap implements sort.Interface.Swap
func (s sortableContainers) Swap(i, j int) { s[i], s[j] = s[j], s[i] }