package steam

import (
	"encoding/json"
	"sync"
	"time"

	"fmt"
	"os"
)

var debuglogging = false

func debugLogJob(s string, args ...interface{}) {
	if debuglogging {
		fmt.Fprintf(os.Stderr, s, args...)
	}
}

func debugLogJobs(s string, args ...interface{}) {
	if debuglogging {
		fmt.Fprintf(os.Stderr, s, args...)
	}
}

// JobStatus provides specific information about an individual job
type Job struct {
	action  string
	target  *Game
	running bool
	start   *time.Time
	errors  []error

	// If applicablle
	size        *int64
	transferred *int64
	eta         *time.Duration

	m sync.Mutex
}

func (j Job) MarshalJSON() ([]byte, error) {
	return json.Marshal(
		struct {
			Action  string     `json:"action"`
			Target  *Game      `json:"Target"`
			Running bool       `json:"Running"`
			Start   *time.Time `json:"Start"`
			Errors  []error    `json:"Errors"`

			// If applicablle
			Size        *int64         `json:"Size"`
			Transferred *int64         `json:"Transferred"`
			Eta         *time.Duration `json:"ETA"`
		}{
			Action:      j.action,
			Target:      j.target,
			Running:     j.running,
			Start:       j.start,
			Errors:      j.errors,
			Size:        j.size,
			Transferred: j.transferred,
			Eta:         j.eta,
		})
}

// Action is a short string describing the action, i.e. "packaging", "deleting"
func (j *Job) Action() string {
	j.m.Lock()
	defer j.m.Unlock()
	debugLogJob("Action on: '%s'\n", *j)
	return j.action
}

// Target returns the game that is the target of the action
func (j *Job) Target() *Game {
	j.m.Lock()
	defer j.m.Unlock()
	debugLogJob("Target on: '%s'\n", *j)
	return j.target
}

// IsRunning returns true if the job is currently running, otherwise false
func (j *Job) IsRunning() bool {
	j.m.Lock()
	defer j.m.Unlock()
	debugLogJob("IsRunning on: '%s'\n", *j)
	return j.running
}

// StartTime returns the time in which the job started
func (j *Job) StartTime() *time.Time {
	j.m.Lock()
	defer j.m.Unlock()
	debugLogJob("StartTime on: '%s'\n", *j)
	return j.start
}

func (j *Job) Errors() []error {
	j.m.Lock()
	defer j.m.Unlock()
	debugLogJob("errors on: '%s'\n", *j)
	return j.errors
}

// newJob sets up a job of action for the target Game
func newJob(action string, target *Game) *Job {
	debugLogJob("New job: '%s' target: '%s'\n", action, target)
	t := time.Now()
	return &Job{
		action:  action,
		target:  target,
		running: true,
		start:   &t,
	}
}

func (j *Job) setSize(size int64) {
	j.m.Lock()
	defer j.m.Unlock()
	debugLogJob("setSize on: '%s'\n", *j)
	j.size = &size
}

// GetSize returns the size set if applicable for the operation
func (j *Job) GetSize() *int64 {
	j.m.Lock()
	defer j.m.Unlock()
	debugLogJob("getSize on: '%s'\n", *j)
	return j.size
}

func (j *Job) setTransferred(transferred int64) {
	j.m.Lock()
	defer j.m.Unlock()
	debugLogJob("setTransferred on: '%s'\n", *j)
	j.transferred = &transferred
}

// GetTransferred returns the transferred set if applicable for the operation
func (j *Job) GetTransferred() *int64 {
	j.m.Lock()
	defer j.m.Unlock()
	debugLogJob("GetTransferred on: '%s'\n", *j)
	return j.transferred
}

// setETA sets the eta to the speicifed duration
func (j *Job) setETA(d time.Duration) {
	j.m.Lock()
	defer j.m.Unlock()
	debugLogJob("setETA on: '%s'\n", *j)
	j.eta = &d
}

// GetETA returns the ETA to completion as a *time.Duration. nil represents
// when
func (j *Job) GetETA() *time.Duration {
	j.m.Lock()
	defer j.m.Unlock()
	debugLogJob("GetETA on: '%s'\n", *j)
	return j.eta
}

// done sets running to false
func (j *Job) done() {
	j.m.Lock()
	defer j.m.Unlock()
	j.running = false
}

// addError appends an error to the internal slice of errors
func (j *Job) addError(err error) {
	j.m.Lock()
	defer j.m.Unlock()
	debugLogJob("add error on: '%s'\n", *j)
	j.errors = append(j.errors, err)
}

// Jobs is by the Library to determine whether or not we currently have any
// jobs running on this library, as well as to give some history as to
// what jobs have been run previously
type Jobs struct {
	running  []*Job
	previous []*Job

	m sync.Mutex
}

func (jobs Jobs) MarshalJSON() ([]byte, error) {
	jobs.scan()
	return json.Marshal(
		struct {
			Running  []*Job `json:"Running"`
			Previous []*Job `json:"Previous"`
		}{
			Running:  jobs.running,
			Previous: jobs.previous,
		})
}

func (jobs Jobs) String() string {
	b, err := json.Marshal(jobs)
	if err != nil {
		panic(err)
	}
	return string(b)
}

func (jobs *Jobs) scan() {
	jobs.m.Lock()
	defer jobs.m.Unlock()
	debugLogJobs("scan on: '%s'\n", *jobs)
	running := []*Job{}
	notrunning := []*Job{}

	for _, job := range jobs.running {
		if job == nil {
			continue
		}

		if job.IsRunning() == true {
			running = append(running, job)
		} else {
			notrunning = append(notrunning, job)
		}
	}

	if len(notrunning) > 0 {
		jobs.previous = append(jobs.previous, notrunning...)
	}

	jobs.running = running
}

// Running returns true if any job is currently running, otherwise false
func (jobs *Jobs) Running() bool {
	jobs.scan()
	jobs.m.Lock()
	defer jobs.m.Unlock()
	if len(jobs.running) == 0 {
		return false
	}
	debugLogJobs("running on: '%s'\n", *jobs)
	return true
}

// GetJobs returns all of the jobs regardless of their state
func (jobs *Jobs) GetJobs() []*Job {
	jobs.scan()
	jobs.m.Lock()
	defer jobs.m.Unlock()
	debugLogJobs("GetJobs on: '%s'\n", *jobs)
	return append(jobs.running, jobs.previous...)
}

// GetRunningJobs returns all of the running jobs
func (jobs *Jobs) GetRunningJobs() []*Job {
	jobs.scan()
	jobs.m.Lock()
	defer jobs.m.Unlock()
	debugLogJobs("GetRunningJobs on: '%s'\n", *jobs)
	return jobs.running
}

// GetStoppedJobs returns all of the stopped jobs
func (jobs *Jobs) GetStoppedJobs() []*Job {
	jobs.scan()
	jobs.m.Lock()
	defer jobs.m.Unlock()
	debugLogJobs("GetStoppedJobs on: '%s'\n", *jobs)
	return jobs.previous
}

// addJob adds a job to the internal slice
func (jobs *Jobs) addJob(j *Job) {
	jobs.m.Lock()
	jobs.running = append(jobs.running, j)
	debugLogJobs("addJob on: '%s'\n", *jobs)
	jobs.m.Unlock()
	jobs.scan()
}