package handlers

import (
	"errors"
	"net/http"
	"strconv"

	"github.com/gin-gonic/gin"

	"github.com/treytartt/casera-api/internal/dto/requests"
	"github.com/treytartt/casera-api/internal/middleware"
	"github.com/treytartt/casera-api/internal/models"
	"github.com/treytartt/casera-api/internal/services"
)

// ResidenceHandler handles residence-related HTTP requests
type ResidenceHandler struct {
	residenceService *services.ResidenceService
	pdfService       *services.PDFService
	emailService     *services.EmailService
}

// NewResidenceHandler creates a new residence handler
func NewResidenceHandler(residenceService *services.ResidenceService, pdfService *services.PDFService, emailService *services.EmailService) *ResidenceHandler {
	return &ResidenceHandler{
		residenceService: residenceService,
		pdfService:       pdfService,
		emailService:     emailService,
	}
}

// ListResidences handles GET /api/residences/
func (h *ResidenceHandler) ListResidences(c *gin.Context) {
	user := c.MustGet(middleware.AuthUserKey).(*models.User)

	response, err := h.residenceService.ListResidences(user.ID)
	if err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
		return
	}

	c.JSON(http.StatusOK, response)
}

// GetMyResidences handles GET /api/residences/my-residences/
func (h *ResidenceHandler) GetMyResidences(c *gin.Context) {
	user := c.MustGet(middleware.AuthUserKey).(*models.User)

	response, err := h.residenceService.GetMyResidences(user.ID)
	if err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
		return
	}

	c.JSON(http.StatusOK, response)
}

// GetResidence handles GET /api/residences/:id/
func (h *ResidenceHandler) GetResidence(c *gin.Context) {
	user := c.MustGet(middleware.AuthUserKey).(*models.User)

	residenceID, err := strconv.ParseUint(c.Param("id"), 10, 32)
	if err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": "Invalid residence ID"})
		return
	}

	response, err := h.residenceService.GetResidence(uint(residenceID), user.ID)
	if err != nil {
		switch {
		case errors.Is(err, services.ErrResidenceNotFound):
			c.JSON(http.StatusNotFound, gin.H{"error": err.Error()})
		case errors.Is(err, services.ErrResidenceAccessDenied):
			c.JSON(http.StatusForbidden, gin.H{"error": err.Error()})
		default:
			c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
		}
		return
	}

	c.JSON(http.StatusOK, response)
}

// CreateResidence handles POST /api/residences/
func (h *ResidenceHandler) CreateResidence(c *gin.Context) {
	user := c.MustGet(middleware.AuthUserKey).(*models.User)

	var req requests.CreateResidenceRequest
	if err := c.ShouldBindJSON(&req); err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
		return
	}

	response, err := h.residenceService.CreateResidence(&req, user.ID)
	if err != nil {
		if errors.Is(err, services.ErrPropertiesLimitReached) {
			c.JSON(http.StatusForbidden, gin.H{"error": err.Error()})
			return
		}
		c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
		return
	}

	c.JSON(http.StatusCreated, response)
}

// UpdateResidence handles PUT/PATCH /api/residences/:id/
func (h *ResidenceHandler) UpdateResidence(c *gin.Context) {
	user := c.MustGet(middleware.AuthUserKey).(*models.User)

	residenceID, err := strconv.ParseUint(c.Param("id"), 10, 32)
	if err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": "Invalid residence ID"})
		return
	}

	var req requests.UpdateResidenceRequest
	if err := c.ShouldBindJSON(&req); err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
		return
	}

	response, err := h.residenceService.UpdateResidence(uint(residenceID), user.ID, &req)
	if err != nil {
		switch {
		case errors.Is(err, services.ErrResidenceNotFound):
			c.JSON(http.StatusNotFound, gin.H{"error": err.Error()})
		case errors.Is(err, services.ErrNotResidenceOwner):
			c.JSON(http.StatusForbidden, gin.H{"error": err.Error()})
		default:
			c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
		}
		return
	}

	c.JSON(http.StatusOK, response)
}

// DeleteResidence handles DELETE /api/residences/:id/
func (h *ResidenceHandler) DeleteResidence(c *gin.Context) {
	user := c.MustGet(middleware.AuthUserKey).(*models.User)

	residenceID, err := strconv.ParseUint(c.Param("id"), 10, 32)
	if err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": "Invalid residence ID"})
		return
	}

	err = h.residenceService.DeleteResidence(uint(residenceID), user.ID)
	if err != nil {
		switch {
		case errors.Is(err, services.ErrResidenceNotFound):
			c.JSON(http.StatusNotFound, gin.H{"error": err.Error()})
		case errors.Is(err, services.ErrNotResidenceOwner):
			c.JSON(http.StatusForbidden, gin.H{"error": err.Error()})
		default:
			c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
		}
		return
	}

	c.JSON(http.StatusOK, gin.H{"message": "Residence deleted successfully"})
}

// GenerateShareCode handles POST /api/residences/:id/generate-share-code/
func (h *ResidenceHandler) GenerateShareCode(c *gin.Context) {
	user := c.MustGet(middleware.AuthUserKey).(*models.User)

	residenceID, err := strconv.ParseUint(c.Param("id"), 10, 32)
	if err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": "Invalid residence ID"})
		return
	}

	var req requests.GenerateShareCodeRequest
	// Request body is optional
	c.ShouldBindJSON(&req)

	response, err := h.residenceService.GenerateShareCode(uint(residenceID), user.ID, req.ExpiresInHours)
	if err != nil {
		switch {
		case errors.Is(err, services.ErrResidenceNotFound):
			c.JSON(http.StatusNotFound, gin.H{"error": err.Error()})
		case errors.Is(err, services.ErrNotResidenceOwner):
			c.JSON(http.StatusForbidden, gin.H{"error": err.Error()})
		default:
			c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
		}
		return
	}

	c.JSON(http.StatusOK, response)
}

// JoinWithCode handles POST /api/residences/join-with-code/
func (h *ResidenceHandler) JoinWithCode(c *gin.Context) {
	user := c.MustGet(middleware.AuthUserKey).(*models.User)

	var req requests.JoinWithCodeRequest
	if err := c.ShouldBindJSON(&req); err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
		return
	}

	response, err := h.residenceService.JoinWithCode(req.Code, user.ID)
	if err != nil {
		switch {
		case errors.Is(err, services.ErrShareCodeInvalid):
			c.JSON(http.StatusNotFound, gin.H{"error": err.Error()})
		case errors.Is(err, services.ErrShareCodeExpired):
			c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
		case errors.Is(err, services.ErrUserAlreadyMember):
			c.JSON(http.StatusConflict, gin.H{"error": err.Error()})
		default:
			c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
		}
		return
	}

	c.JSON(http.StatusOK, response)
}

// GetResidenceUsers handles GET /api/residences/:id/users/
func (h *ResidenceHandler) GetResidenceUsers(c *gin.Context) {
	user := c.MustGet(middleware.AuthUserKey).(*models.User)

	residenceID, err := strconv.ParseUint(c.Param("id"), 10, 32)
	if err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": "Invalid residence ID"})
		return
	}

	users, err := h.residenceService.GetResidenceUsers(uint(residenceID), user.ID)
	if err != nil {
		switch {
		case errors.Is(err, services.ErrResidenceNotFound):
			c.JSON(http.StatusNotFound, gin.H{"error": err.Error()})
		case errors.Is(err, services.ErrResidenceAccessDenied):
			c.JSON(http.StatusForbidden, gin.H{"error": err.Error()})
		default:
			c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
		}
		return
	}

	c.JSON(http.StatusOK, users)
}

// RemoveResidenceUser handles DELETE /api/residences/:id/users/:user_id/
func (h *ResidenceHandler) RemoveResidenceUser(c *gin.Context) {
	user := c.MustGet(middleware.AuthUserKey).(*models.User)

	residenceID, err := strconv.ParseUint(c.Param("id"), 10, 32)
	if err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": "Invalid residence ID"})
		return
	}

	userIDToRemove, err := strconv.ParseUint(c.Param("user_id"), 10, 32)
	if err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": "Invalid user ID"})
		return
	}

	err = h.residenceService.RemoveUser(uint(residenceID), uint(userIDToRemove), user.ID)
	if err != nil {
		switch {
		case errors.Is(err, services.ErrResidenceNotFound):
			c.JSON(http.StatusNotFound, gin.H{"error": err.Error()})
		case errors.Is(err, services.ErrNotResidenceOwner):
			c.JSON(http.StatusForbidden, gin.H{"error": err.Error()})
		case errors.Is(err, services.ErrCannotRemoveOwner):
			c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
		default:
			c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
		}
		return
	}

	c.JSON(http.StatusOK, gin.H{"message": "User removed from residence"})
}

// GetResidenceTypes handles GET /api/residences/types/
func (h *ResidenceHandler) GetResidenceTypes(c *gin.Context) {
	types, err := h.residenceService.GetResidenceTypes()
	if err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
		return
	}

	c.JSON(http.StatusOK, types)
}

// GenerateTasksReport handles POST /api/residences/:id/generate-tasks-report/
// Generates a PDF report of tasks for the residence and emails it
func (h *ResidenceHandler) GenerateTasksReport(c *gin.Context) {
	user := c.MustGet(middleware.AuthUserKey).(*models.User)

	residenceID, err := strconv.ParseUint(c.Param("id"), 10, 32)
	if err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": "Invalid residence ID"})
		return
	}

	// Optional request body for email recipient
	var req struct {
		Email string `json:"email"`
	}
	c.ShouldBindJSON(&req)

	// Generate the report data
	report, err := h.residenceService.GenerateTasksReport(uint(residenceID), user.ID)
	if err != nil {
		switch {
		case errors.Is(err, services.ErrResidenceNotFound):
			c.JSON(http.StatusNotFound, gin.H{"error": err.Error()})
		case errors.Is(err, services.ErrResidenceAccessDenied):
			c.JSON(http.StatusForbidden, gin.H{"error": err.Error()})
		default:
			c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
		}
		return
	}

	// Determine recipient email
	recipientEmail := req.Email
	if recipientEmail == "" {
		recipientEmail = user.Email
	}

	// Get recipient name
	recipientName := user.FirstName
	if recipientName == "" {
		recipientName = user.Username
	}

	// Generate PDF if PDF service is available
	var pdfGenerated bool
	var emailSent bool
	if h.pdfService != nil && h.emailService != nil {
		pdfData, pdfErr := h.pdfService.GenerateTasksReportPDF(report)
		if pdfErr == nil {
			pdfGenerated = true

			// Send email with PDF attachment
			emailErr := h.emailService.SendTasksReportEmail(
				recipientEmail,
				recipientName,
				report.ResidenceName,
				report.TotalTasks,
				report.Completed,
				report.Pending,
				report.Overdue,
				pdfData,
			)
			if emailErr == nil {
				emailSent = true
			}
		}
	}

	// Build response message
	message := "Tasks report generated successfully"
	if pdfGenerated && emailSent {
		message = "Tasks report generated and sent to " + recipientEmail
	} else if pdfGenerated && !emailSent {
		message = "Tasks report generated but email could not be sent"
	}

	c.JSON(http.StatusOK, gin.H{
		"message":         message,
		"residence_name":  report.ResidenceName,
		"recipient_email": recipientEmail,
		"pdf_generated":   pdfGenerated,
		"email_sent":      emailSent,
		"report":          report,
	})
}