package taskwarrior

import (
	"bytes"
	"encoding/json"
	"os/exec"
)

/// A task with an Id of 0 is either `completed` or `deleted` which is also
/// mentioned in the Status field

type Task struct {
	Id          uint         `json:"id,omitempty"`
	Project     string       `json:"project,omitempty"`
	Tags        []string     `json:"tags,omitempty"`
	Description string       `json:"description,omitempty"`
	Annotations []Annotation `json:"annotations,omitempty"`
	Status      string       `json:"status,omitempty"`
	Due         string       `json:"due,omitempty"`
	Entry       string       `json:"entry,omitempty"`
	Modified    string       `json:"modified,omitempty"`
	End         string       `json:"end,omitempty"`
	Uuid        string       `json:"uuid,omitempty"`
	Urgency     float32      `json:"urgency,omitempty"`
}

type Annotation struct {
	Description string `json:"description,omitempty"`
	Entry       string `json:"entry,omitempty"`
}

func NewTask(description string, project string, tags ...string) Task {
	return Task{
		Project:     project,
		Tags:        tags,
		Description: description,
	}
}

func GetTasks(filter Filter) ([]Task, error) {
	filter.filter = append(filter.filter, "export")
	cmd := exec.Command("task", filter.filter...)
	out, err := cmd.Output()
	if err != nil {
		return nil, err
	}
	var tasks []Task
	decoder := json.NewDecoder(bytes.NewBuffer(out))
	decoder.DisallowUnknownFields()
	if err = decoder.Decode(&tasks); err != nil {
		return nil, err
	}
	return tasks, nil
}

func UpdateTasks(tasks []Task) error {
	cmd := exec.Command("task", "import")
	value, err := json.Marshal(tasks)
	if err != nil {
		return err
	}
	var buffer bytes.Buffer
	_, err = buffer.Write(value)
	if err != nil {
		return err
	}
	cmd.Stdin = &buffer
	return cmd.Run()
}