package ajax

import (
	"encoding/json"
	"errors"
	"fmt"
	"local/todo-server/server/ajax/form"
	"local/todo-server/server/ajax/task"
	"net/http"
	"strconv"
	"strings"
)

func (a *Ajax) loadTasks(w http.ResponseWriter, r *http.Request) error {
	listID, _, _ := a.Cur(r)
	filterComplete := func(t *task.Task) bool {
		if form.Get(r, "compl") == "" {
			return true
		}
		return form.Get(r, "compl") == "1" || !t.Complete
	}
	filterTags := func(t *task.Task) bool {
		if form.Get(r, "t") == "" {
			return true
		}
		whitelistTags := form.ToStrArr(form.Get(r, "t"))
		if len(whitelistTags) == 0 {
			return true
		}
		for _, whitelisted := range whitelistTags {
			found := false
			for _, tag := range t.Tags {
				if whitelisted == tag {
					found = true
				}
			}
			if !found {
				return false
			}
		}
		return true
	}
	filterSubstr := func(t *task.Task) bool {
		substr := form.Get(r, "s")
		return substr == "" || strings.Contains(fmt.Sprintf("%+v", t), substr)
	}
	tasks, err := a.storageListTasks(listID, filterComplete, filterTags, filterSubstr)
	if err != nil {
		return err
	}
	return json.NewEncoder(w).Encode(map[string]interface{}{"list": tasks})
}

func (a *Ajax) newTask(w http.ResponseWriter, r *http.Request) error {
	listID, newTask, err := a.makeTask(r)
	if err != nil {
		return err
	}
	if err := a.storageSetTask(listID, newTask); err != nil {
		return err
	}
	return json.NewEncoder(w).Encode(map[string]interface{}{
		"total": 1,
		"list":  []*task.Task{newTask},
	})
}

func (a *Ajax) makeTask(r *http.Request) (string, *task.Task, error) {
	listID, _, tags := a.Cur(r)
	task, err := task.New(r)
	if err != nil {
		return "", nil, err
	}
	list, err := a.storageGetList(listID)
	if err != nil {
		return "", nil, err
	}
	task.Index = list.NextIndex()
	if err := a.storageSetList(list); err != nil {
		return "", nil, err
	}
	task.AppendTags(tags)
	return listID, task, nil
}

func (a *Ajax) deleteTask(w http.ResponseWriter, r *http.Request) error {
	_, taskID, _ := a.Cur(r)
	return a.storageDelTask(taskID)
}

func (a *Ajax) completeTask(w http.ResponseWriter, r *http.Request) error {
	listID, taskID, _ := a.Cur(r)
	completedTask, err := a.storageGetTask(taskID)
	if err != nil {
		return err
	}
	if err := a.storageDelTask(completedTask.UUID); err != nil {
		return err
	}
	completedTask.SetComplete(form.Get(r, "compl") == "1")
	if err := a.storageSetTask(listID, completedTask); err != nil {
		return err
	}
	return json.NewEncoder(w).Encode(map[string]interface{}{
		"total": 1,
		"list":  []*task.Task{completedTask},
	})
}

func (a *Ajax) editNote(w http.ResponseWriter, r *http.Request) error {
	listID, taskID, _ := a.Cur(r)
	task, err := a.storageGetTask(taskID)
	if err != nil {
		return err
	}
	task.SetNote(form.Get(r, "note"))
	return a.storageSetTask(listID, task)
}

func (a *Ajax) editTask(w http.ResponseWriter, r *http.Request) error {
	listID, task, err := a.makeTask(r)
	if err != nil {
		return err
	}
	_, taskID, _ := a.Cur(r)
	task.UUID = taskID
	return a.storageSetTask(listID, task)
}

func (a *Ajax) setPrio(w http.ResponseWriter, r *http.Request) error {
	listID, taskID, _ := a.Cur(r)
	task, err := a.storageGetTask(taskID)
	if err != nil {
		return err
	}
	task.SetPrio(form.ToInt(form.Get(r, "prio")))
	return a.storageSetTask(listID, task)
}

func (a *Ajax) moveTask(w http.ResponseWriter, r *http.Request) error {
	_, taskID, _ := a.Cur(r)
	toList := form.Get(r, "to")
	task, err := a.storageGetTask(taskID)
	if err != nil {
		return err
	}
	if err := a.storageDelTask(taskID); err != nil {
		return err
	}
	return a.storageSetTask(toList, task)
}

func (a *Ajax) parseTaskStr(w http.ResponseWriter, r *http.Request) error {
	return errors.New("not impl")
}

func (a *Ajax) changeOrder(w http.ResponseWriter, r *http.Request) error {
	order := form.Get(r, "order")
	orders := strings.Split(order, "&")
	sum := 0
	zero := ""
	for _, order := range orders {
		taskIDDelta := strings.Split(order, "=")
		if len(taskIDDelta) < 2 {
			continue
		}
		taskID := taskIDDelta[0]
		delta, _ := strconv.Atoi(taskIDDelta[1])
		if delta < 0 {
			delta = -1
		} else {
			delta = 0
		}
		task, err := a.storageGetTask(taskID)
		if err != nil {
			return err
		}
		listID, err := a.taskIDToListID(taskID)
		if err != nil {
			return err
		}
		task.Index += delta
		if err := a.storageSetTask(listID, task); err != nil {
			return err
		}
		if delta == 0 {
			zero = taskID
		}
		sum += delta
	}
	if zero == "" || sum == 0 {
		return nil
	}
	task, err := a.storageGetTask(zero)
	if err != nil {
		return err
	}
	listID, err := a.taskIDToListID(zero)
	if err != nil {
		return err
	}
	task.Index -= sum
	if err := a.storageSetTask(listID, task); err != nil {
		return err
	}
	fmt.Fprint(w, `{"total":1}`)
	return nil
}