package gime

import (
	"errors"
	"time"

	"github.com/pborman/uuid"
)

// Entry is a time entry
type TimeEntry struct {
	uuid  string
	start time.Time
	end   time.Time
	tags  []string
}

// CreateTimeEntry creates an entry with the given parameters and returns it.
// An error is returned if no start time is given or if the end time given is
// non-zero and earlier than the start time.
func CreateTimeEntry(s, e time.Time, t []string) (*TimeEntry, error) {
	ret := new(TimeEntry)
	ret.uuid = uuid.New()
	if s.IsZero() {
		// No start time given, return error
		return ret, errors.New("No start time given")
	}
	if !e.IsZero() {
		if !e.After(s) {
			// Given end time is earlier than start time
			return ret, errors.New("End time is before start time")
		}
	}
	return &TimeEntry{start: s, end: e, tags: t}, nil
}

// GetStart returns the start time for the entry
func (t *TimeEntry) GetStart() time.Time {
	return t.start
}

// SetStart sets the start time on the time entry
func (t *TimeEntry) SetStart(s time.Time) {
	t.start = s
}

// GetEnd returns the end time for the entry
func (t *TimeEntry) GetEnd() time.Time {
	return t.end
}

// SetEnd sets the end time on the time entry
func (t *TimeEntry) SetEnd(e time.Time) {
	t.end = e
}

// IsActive return true if start is earlier than now and end is zero
func (t *TimeEntry) IsActive() bool {
	return time.Now().After(t.start) && !t.end.IsZero()
}

// GetTags returns all of the tags associated with this time entry
func (t *TimeEntry) GetTags() []string {
	return t.tags
}

// HasTag returns if the time entry contains a specific tag
func (t *TimeEntry) HasTag(s string) bool {
	for i := range t.tags {
		if t.tags[i] == s {
			return true
		}
	}
	return false
}

// AddTag adds a tag to the time entry (if it isn't already there)
func (t *TimeEntry) AddTag(s string) {
	if !t.HasTag(s) {
		t.tags = append(t.tags, s)
	}
}

// RemoveTag removes a tag from the time entry
func (t *TimeEntry) RemoveTag(s string) {
	var i int
	var fnd bool
	for i = range t.tags {
		if t.tags[i] == s {
			fnd = true
			break
		}
	}
	if fnd {
		t.tags = append(t.tags[:i], t.tags[i+1:]...)
	}
}

func (t *TimeEntry) Equals(tst *TimeEntry) bool {
	return t.uuid == tst.uuid
}