package v1

import (
	"net/http"

	"github.com/gin-gonic/gin"
	"github.com/gochat/gochat/internal/model"
	"github.com/gochat/gochat/internal/service"
)

// InboxMemberHandler handles inbox member (seat assignment) API endpoints.
// Reference: Chatwoot app/controllers/api/v1/inbox_members_controller.rb
// Routes manage which agents are assigned to which inboxes (seat assignment).
type InboxMemberHandler struct {
	svc *service.InboxMemberService
}

// NewInboxMemberHandler creates a new InboxMemberHandler.
func NewInboxMemberHandler(svc *service.InboxMemberService) *InboxMemberHandler {
	return &InboxMemberHandler{svc: svc}
}

// ListMembers retrieves all agents assigned to an inbox.
// GET /api/v1/accounts/:id/inboxes/:inbox_id/members
// Reference: Chatwoot inbox_members#index
func (h *InboxMemberHandler) ListMembers(c *gin.Context) {
	inboxID, err := parseUintParam(c, "inbox_id")
	if err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": "invalid inbox id"})
		return
	}

	members, svcErr := h.svc.ListByInbox(c.Request.Context(), inboxID)
	if svcErr != nil {
		c.JSON(http.StatusUnprocessableEntity, gin.H{"error": "failed to list inbox members"})
		return
	}

	c.JSON(http.StatusOK, inboxMembersPayload(members))
}

// AddMember assigns an agent to an inbox (seat assignment).
// POST /api/v1/accounts/:id/inboxes/:inbox_id/members
// Reference: Chatwoot inbox_members#create
func (h *InboxMemberHandler) AddMember(c *gin.Context) {
	inboxID, err := parseUintParam(c, "inbox_id")
	if err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": "invalid inbox id"})
		return
	}

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

	// Override inbox_id from URL path parameter
	req.InboxID = inboxID

	member, svcErr := h.svc.AddMember(c.Request.Context(), req)
	if svcErr != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": svcErr.Error()})
		return
	}

	c.JSON(http.StatusCreated, inboxMembersPayload([]model.InboxMember{*member}))
}

// RemoveMember removes an agent from an inbox (unassign seat).
// DELETE /api/v1/accounts/:id/inboxes/:inbox_id/members/:user_id
// Reference: Chatwoot inbox_members#destroy
func (h *InboxMemberHandler) RemoveMember(c *gin.Context) {
	inboxID, err := parseUintParam(c, "inbox_id")
	if err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": "invalid inbox id"})
		return
	}

	userID, err := parseUintParam(c, "user_id")
	if err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": "invalid user id"})
		return
	}

	if svcErr := h.svc.RemoveMember(c.Request.Context(), inboxID, userID); svcErr != nil {
		c.JSON(http.StatusUnprocessableEntity, gin.H{"error": "failed to remove member"})
		return
	}

	c.JSON(http.StatusOK, gin.H{"inbox_id": inboxID, "user_id": userID, "removed": true})
}

// UpdateMember updates a member's role or availability status.
// PATCH /api/v1/accounts/:id/inboxes/:inbox_id/members/:user_id
// Reference: Chatwoot inbox_members#update
func (h *InboxMemberHandler) UpdateMember(c *gin.Context) {
	inboxID, err := parseUintParam(c, "inbox_id")
	if err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": "invalid inbox id"})
		return
	}

	userID, err := parseUintParam(c, "user_id")
	if err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": "invalid user id"})
		return
	}

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

	member, svcErr := h.svc.UpdateMember(c.Request.Context(), inboxID, userID, req)
	if svcErr != nil {
		c.JSON(http.StatusUnprocessableEntity, gin.H{"error": "failed to update member"})
		return
	}

	c.JSON(http.StatusOK, inboxMembersPayload([]model.InboxMember{*member}))
}

// UpdateMultiple replaces all members of an inbox with a new set of user IDs (batch seat assignment).
// PATCH /api/v1/accounts/:id/inboxes/:inbox_id/members/update_multiple
// Reference: Chatwoot inbox_members#update (batch replace)
func (h *InboxMemberHandler) UpdateMultiple(c *gin.Context) {
	inboxID, err := parseUintParam(c, "inbox_id")
	if err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": "invalid inbox id"})
		return
	}

	var req service.UpdateMultipleRequest
	if bindErr := c.ShouldBindJSON(&req); bindErr != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": bindErr.Error()})
		return
	}
	req.InboxID = inboxID

	members, svcErr := h.svc.UpdateMultiple(c.Request.Context(), req)
	if svcErr != nil {
		c.JSON(http.StatusUnprocessableEntity, gin.H{"error": "failed to update members"})
		return
	}

	c.JSON(http.StatusOK, inboxMembersPayload(members))
}

// ShowAccountScoped retrieves all agents assigned to an inbox using Chatwoot's account-level route.
// GET /api/v1/accounts/:account_id/inbox_members/:inbox_id
func (h *InboxMemberHandler) ShowAccountScoped(c *gin.Context) {
	inboxID, err := parseUintParam(c, "inbox_id")
	if err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": "invalid inbox id"})
		return
	}

	members, svcErr := h.svc.ListByInbox(c.Request.Context(), inboxID)
	if svcErr != nil {
		c.JSON(http.StatusUnprocessableEntity, gin.H{"error": "failed to list inbox members"})
		return
	}

	c.JSON(http.StatusOK, inboxMembersPayload(members))
}

// CreateAccountScoped adds or replaces inbox members using Chatwoot's account-level create route.
// POST /api/v1/accounts/:account_id/inbox_members
func (h *InboxMemberHandler) CreateAccountScoped(c *gin.Context) {
	var req service.UpdateMultipleRequest
	if bindErr := c.ShouldBindJSON(&req); bindErr != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": bindErr.Error()})
		return
	}

	members, svcErr := h.svc.AddMembers(c.Request.Context(), req)
	if svcErr != nil {
		c.JSON(http.StatusUnprocessableEntity, gin.H{"error": "failed to update members"})
		return
	}

	c.JSON(http.StatusOK, inboxMembersPayload(members))
}

// UpdateAccountScoped replaces all members of an inbox using Chatwoot's account-level update route.
// PATCH /api/v1/accounts/:account_id/inbox_members
func (h *InboxMemberHandler) UpdateAccountScoped(c *gin.Context) {
	h.updateAccountScoped(c)
}

func (h *InboxMemberHandler) updateAccountScoped(c *gin.Context) {
	var req service.UpdateMultipleRequest
	if bindErr := c.ShouldBindJSON(&req); bindErr != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": bindErr.Error()})
		return
	}

	members, svcErr := h.svc.UpdateMultiple(c.Request.Context(), req)
	if svcErr != nil {
		c.JSON(http.StatusUnprocessableEntity, gin.H{"error": "failed to update members"})
		return
	}

	c.JSON(http.StatusOK, inboxMembersPayload(members))
}

// DestroyAccountScoped removes selected users from an inbox using Chatwoot's account-level route.
// DELETE /api/v1/accounts/:account_id/inbox_members
func (h *InboxMemberHandler) DestroyAccountScoped(c *gin.Context) {
	var req struct {
		InboxID uint   `json:"inbox_id" binding:"required"`
		UserIDs []uint `json:"user_ids" binding:"required"`
	}
	if bindErr := c.ShouldBindJSON(&req); bindErr != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": bindErr.Error()})
		return
	}

	for _, userID := range req.UserIDs {
		if svcErr := h.svc.RemoveMember(c.Request.Context(), req.InboxID, userID); svcErr != nil {
			c.JSON(http.StatusUnprocessableEntity, gin.H{"error": "failed to remove member"})
			return
		}
	}

	c.Status(http.StatusOK)
}

func inboxMembersPayload(members []model.InboxMember) gin.H {
	payload := make([]gin.H, 0, len(members))
	for _, member := range members {
		payload = append(payload, serializeInboxMemberAgent(member))
	}
	return gin.H{"payload": payload}
}

func serializeInboxMemberAgent(member model.InboxMember) gin.H {
	user := member.User
	availableName := user.DisplayName
	if availableName == "" {
		availableName = user.Name
	}
	if availableName == "" {
		availableName = user.Email
	}
	availabilityStatus := member.AvailabilityStatus
	if availabilityStatus == "" {
		if user.Available {
			availabilityStatus = "online"
		} else {
			availabilityStatus = "offline"
		}
	}
	role := user.Role
	if role == "" {
		role = member.Role
	}
	if role == "" {
		role = "agent"
	}
	return gin.H{
		"id":                  user.ID,
		"account_id":          member.Inbox.AccountID,
		"availability_status": availabilityStatus,
		"auto_offline":        true,
		"confirmed":           user.ConfirmedAt != nil,
		"email":               user.Email,
		"provider":            user.Provider,
		"available_name":      availableName,
		"name":                user.Name,
		"role":                role,
		"thumbnail":           user.AvatarURL,
		"custom_role_id":      user.CustomRoleID,
	}
}