package sizer

import (
	"fmt"

	"github.com/gosuri/uilive"
)

// Ruspa is the asynchronous worker that is in charge of collecting
// the underlying sizes and relay the total to the eventual parent.
type Ruspa struct {
	INode  *INode
	Send   chan StatusReport
	Recv   chan StatusReport
	Done   chan StatusReport
	Opened map[string]*Ruspa
}

// NewRuspa inits a new Ruspa
func NewRuspa(inode *INode, collect chan StatusReport) *Ruspa {
	var r Ruspa
	r.INode = inode
	r.Recv = make(chan StatusReport)
	if collect == nil {
		r.Send = make(chan StatusReport)
	} else {
		r.Send = collect
	}
	r.Done = make(chan StatusReport)
	r.Opened = make(map[string]*Ruspa)
	return &r
}

// Scava starts a worker on the given INode.
func (w *Ruspa) Scava(done chan StatusReport) {
	Console.Debugln("Scava: ", w.INode.Path)
	children, err := ls(w.INode.Path)
	if err != nil {
		w.Send <- StatusReport{path: w.INode.Path, err: err}
	}
	for _, childPath := range children {
		kind, size, err := IdentifyType(childPath)
		if err != nil {
			w.Send <- StatusReport{path: childPath, err: err}
		}
		childINode := NewINode(kind, size, childPath)
		w.INode.Children.Append(childINode)
		switch {
		case kind == FileType:
			Console.Debugln("[file]", w.INode.Path, " ~> ", childINode.Path)
			w.Send <- StatusReport{path: childPath, size: size}
		case kind == DirType:
			Console.Debugln("[dir]", w.INode.Path, " ~> ", childINode.Path)
			cw := NewRuspa(childINode, w.Recv)
			w.Opened[childPath] = cw
			go cw.Scava(w.Done)
			// go cw.Ammucchia(w.Done)
		}
	}
	if len(w.Opened) == 0 {
		done <- StatusReport{path: w.INode.Path}
	} else {
		go w.Ammucchia(done)
	}
}

// Ammucchia gathers the size of the underlying Ruspa workers
// and adds to the INode size.
func (w *Ruspa) Ammucchia(done chan StatusReport) {
	for len(w.Opened) > 0 {
		select {
		case report := <-w.Recv:
			if report.err != nil {
				Console.Debugln(Red(report.err))
			}
			if report.err == nil {
				w.INode.Size += report.size
			}
		case leaf := <-w.Done:
			Console.Debugln("Done:", leaf.path)
			delete(w.Opened, leaf.path)
		}
	}
	Console.Debugln(w.INode.Path, ": Completed. Exiting...")
	done <- StatusReport{path: w.INode.Path, size: w.INode.Size}
}

// Pesa starts the worker for current inode and returns the channel
// to listen to get the size.
func (i *INode) Pesa(done chan StatusReport) chan StatusReport {
	result := make(chan StatusReport)
	w := NewRuspa(i, result)
	go w.Scava(done)
	// go w.Ammucchia(done)
	return result
}

// NastroConvogliatore starts a Pesa on a given path and displays
// the current value of the size.
func NastroConvogliatore(path string) {
	pathINode, err := INodeFromPath(path)
	if err != nil {
		Console.Fatalln("Failed creating inode:", err)
	}
	Console.Debugln("Starting Pesa on path:", path)
	done := make(chan StatusReport)
	result := pathINode.Pesa(done)
	writer := uilive.New()
	writer.Start()
	fmt.Fprintf(writer, "%s\n", Green("Starting..."))
	for {
		select {
		case res := <-result:
			fmt.Fprintf(writer, "%s: %d\n", res.path, res.size)
		case res := <-done:
			fmt.Fprintf(writer, "%s: %d\n", res.path, res.size)
			writer.Stop()
			return
		}
	}
}