package handler

import (
	"fmt"
	"net/http"
	"strings"
	"time"

	"git.kundeng.us/phoenix/textsender-models/tx0/message/scheduling"
	"github.com/google/uuid"

	"git.kundeng.us/phoenix/textsender-api/internal/app"
	"git.kundeng.us/phoenix/textsender-api/internal/store"
)

type ScheduledMessageHandler struct {
	App                   *app.App
	ScheduledMessageStore store.ScheduledMessageStore
}

func NewScheduledMessageHandler(apiApp *app.App, str store.ScheduledMessageStore) *ScheduledMessageHandler {
	return &ScheduledMessageHandler{App: apiApp, ScheduledMessageStore: str}
}

type RequestAddScheduledMessage struct {
	Scheduled time.Time `json:"scheduled"`
	Status    string    `json:"status"`
	UserId    uuid.UUID `json:"user_id"`
}

type AddScheduledMessageResponse struct {
	Message string                        `json:"message"`
	Data    []scheduling.ScheduledMessage `json:"data"`
}

// AddScheduledMessage godoc
// @Summary      Add scheduled message
// @Description  Adds a scheduled message (requires JWT)
// @Tags         scheduled messages
// @Accept       json
// @Produce      json
// @Security     BearerAuth
// @Param        request body   RequestAddScheduledMessage   true  "Data to add scheduled message"
// @Success      201  {object}  AddScheduledMessageResponse
// @Failure      400  {object}  AddScheduledMessageResponse
// @Failure      500  {object}  AddScheduledMessageResponse
// @Router       /schedule/message [post]
func (s *ScheduledMessageHandler) AddScheduledMessage(w http.ResponseWriter, r *http.Request) {
	if r.Method != http.MethodPost {
		http.Error(w, "Method not allowed", http.StatusMethodNotAllowed)
		return
	}

	var req RequestAddScheduledMessage
	if err := ExtractFromRequest(r, &req); err != nil {
		http.Error(w, "Invalid JSON: "+err.Error(), http.StatusBadRequest)
	}
	defer r.Body.Close()

	scheduledMessage := scheduling.ScheduledMessage{Scheduled: req.Scheduled, Status: req.Status, UserId: req.UserId}

	var statusCode int
	var resp AddScheduledMessageResponse

	if scheduledMessage.UserId == uuid.Nil {
		statusCode = http.StatusBadRequest
		resp.Message = "No UserId"
	} else {
		ctx := r.Context()

		if validStatus, err := IsStatusValid(&scheduledMessage); err == nil {
			if validStatus {
				if valid, err := isScheduledTimeValid(&scheduledMessage); err == nil && valid {
					if err = s.ScheduledMessageStore.CreateScheduledMessage(ctx, &scheduledMessage); err == nil {
						statusCode = http.StatusCreated
						resp.Data = append(resp.Data, scheduledMessage)
						resp.Message = "Successful"
					} else {
						statusCode = http.StatusInternalServerError
						resp.Message = err.Error()
					}
				} else {
					statusCode = http.StatusBadRequest
					resp.Message = "Invalid scheduled time"
				}
			} else {
				statusCode = http.StatusBadRequest
				resp.Message = "Invalid status"
			}
		} else {
			statusCode = http.StatusInternalServerError
			resp.Message = err.Error()
		}
	}

	RespondWithJSON(w, statusCode, &resp)
}

type GetScheduledMessageResponse struct {
	Message string                        `json:"message"`
	Data    []scheduling.ScheduledMessage `json:"data"`
}

// GetScheduledMessage godoc
// @Summary      Get scheduled message
// @Description  Get a scheduled message (requires JWT)
// @Tags         scheduled messages
// @Accept       json
// @Produce      json
// @Security     BearerAuth
// @Param        id   path      string  true  "Contact Id"
// @Param        user_id   path      string  true  "User Id"
// @Success      200  {object}  GetScheduledMessageResponse
// @Failure      400  {object}  GetScheduledMessageResponse
// @Failure      500  {object}  GetScheduledMessageResponse
// @Router       /schedule/message [get]
func (s *ScheduledMessageHandler) GetScheduledMessage(w http.ResponseWriter, r *http.Request) {
	var id, userId uuid.UUID

	if idParam, err := ParseQueryParams(r, "id"); err == nil {
		var err error
		id, err = uuid.Parse(*idParam)
		if err != nil {
			http.Error(w, "Error parsing Id", http.StatusBadRequest)
			return
		}
	}
	if userIdParam, err := ParseQueryParams(r, "user_id"); err == nil {
		userId, err = uuid.Parse(*userIdParam)
		if err != nil {
			http.Error(w, "Error parsing Id", http.StatusBadRequest)
			return
		}
	}

	var resp GetScheduledMessageResponse
	var statusCode int
	ctx := r.Context()

	if userId == uuid.Nil && id == uuid.Nil {
		http.Error(w, "Invalid query parameters", http.StatusBadRequest)
		return
	} else if userId != uuid.Nil && id != uuid.Nil {
		if schMsgs, err := s.ScheduledMessageStore.GetWithUserId(ctx, userId); err != nil {
			statusCode = http.StatusInternalServerError
			resp.Message = err.Error()
		} else {
			for _, schMsg := range schMsgs {
				if schMsg.Id == id {
					resp.Data = append(resp.Data, *schMsg)
				}
			}
			statusCode = http.StatusOK
			resp.Message = "Successful"
		}
	} else if id != uuid.Nil {
		if schMsg, err := s.ScheduledMessageStore.Get(ctx, id); err != nil {
			statusCode = http.StatusInternalServerError
			resp.Message = err.Error()
		} else {
			statusCode = http.StatusOK
			resp.Message = "Successful"
			resp.Data = append(resp.Data, *schMsg)
		}
	} else {
		if schMsgs, err := s.ScheduledMessageStore.GetWithUserId(ctx, userId); err != nil {
			statusCode = http.StatusInternalServerError
			resp.Message = err.Error()
		} else {
			statusCode = http.StatusOK
			resp.Message = "Successful"
			for _, schMsg := range schMsgs {
				resp.Data = append(resp.Data, *schMsg)
			}
		}
	}

	RespondWithJSON(w, statusCode, &resp)
}

type FetchNextMessageResponse struct {
	Message string                        `json:"message"`
	Data    []scheduling.ScheduledMessage `json:"data"`
}

// FetchNextMessage godoc
// @Summary      Fetch scheduled message
// @Description  Fetches a scheduled message that is available to be processed (requires JWT)
// @Tags         scheduled messages
// @Accept       json
// @Produce      json
// @Security     BearerAuth
// @Success      200  {object}  FetchNextMessageResponse
// @Failure      400  {object}  FetchNextMessageResponse
// @Failure      500  {object}  FetchNextMessageResponse
// @Router       /schedule/message/fetch [get]
func (s *ScheduledMessageHandler) FetchNextMessage(w http.ResponseWriter, r *http.Request) {
	ctx := r.Context()
	var resp FetchNextMessageResponse
	var statusCode int

	if schMsg, err := s.ScheduledMessageStore.FetchNextScheduledMessage(ctx); err != nil {
		statusCode = http.StatusInternalServerError
		resp.Message = err.Error()
	} else {
		if schMsg != nil {
			statusCode = http.StatusOK
			resp.Message = "Successful"
			resp.Data = append(resp.Data, *schMsg)
		} else {
			statusCode = http.StatusNotFound
			resp.Message = "No item"
		}
	}

	RespondWithJSON(w, statusCode, &resp)
}

func isScheduledTimeValid(schMsg *scheduling.ScheduledMessage) (bool, error) {
	now := time.Now()
	timeCutOff := now.Add(-5 * time.Minute)
	futureCutOff := now.Add((24 * 7) * time.Hour)

	if schMsg.Scheduled.After(timeCutOff) {
		if schMsg.Scheduled.Before(futureCutOff) {
			return true, nil
		} else {
			return false, fmt.Errorf("Scheduled Time is too far in the future")
		}
	} else {
		return false, nil
	}
}

func IsStatusValid(schMsg *scheduling.ScheduledMessage) (bool, error) {
	schMsg.Status = strings.ToUpper(schMsg.Status)
	if schMsg.Status == scheduling.Pending {
		return true, nil
	} else {
		return false, fmt.Errorf("Status is not valid for creating scheduled message %s", schMsg.Status)
	}
}