// Copyright 2014 The Gogs Authors. All rights reserved.
// Copyright 2019 The Gitea Authors. All rights reserved.
// Use of this source code is governed by a MIT-style
// license that can be found in the LICENSE file.

package cron

import (
	"context"
	"time"

	"code.gitea.io/gitea/modules/graceful"
	"code.gitea.io/gitea/modules/sync"

	"github.com/gogs/cron"
)

var c = cron.New()

// Prevent duplicate running tasks.
var taskStatusTable = sync.NewStatusTable()

// NewContext begins cron tasks
// Each cron task is run within the shutdown context as a running server
// AtShutdown the cron server is stopped
func NewContext() {
	initBasicTasks()
	initExtendedTasks()

	lock.Lock()
	for _, task := range tasks {
		if task.IsEnabled() && task.DoRunAtStart() {
			go task.Run()
		}
	}

	c.Start()
	started = true
	lock.Unlock()
	graceful.GetManager().RunAtShutdown(context.Background(), func() {
		c.Stop()
		lock.Lock()
		started = false
		lock.Unlock()
	})

}

// TaskTableRow represents a task row in the tasks table
type TaskTableRow struct {
	Name      string
	Spec      string
	Next      time.Time
	Prev      time.Time
	ExecTimes int64
}

// TaskTable represents a table of tasks
type TaskTable []*TaskTableRow

// ListTasks returns all running cron tasks.
func ListTasks() TaskTable {
	entries := c.Entries()
	eMap := map[string]*cron.Entry{}
	for _, e := range entries {
		eMap[e.Description] = e
	}
	lock.Lock()
	defer lock.Unlock()
	tTable := make([]*TaskTableRow, 0, len(tasks))
	for _, task := range tasks {
		spec := "-"
		var (
			next time.Time
			prev time.Time
		)
		if e, ok := eMap[task.Name]; ok {
			spec = e.Spec
			next = e.Next
			prev = e.Prev
		}
		task.lock.Lock()
		tTable = append(tTable, &TaskTableRow{
			Name:      task.Name,
			Spec:      spec,
			Next:      next,
			Prev:      prev,
			ExecTimes: task.ExecTimes,
		})
		task.lock.Unlock()
	}

	return tTable
}