package v1

// Reference: M13 §3 — SSO session management API
// List, inspect, and terminate active SSO sessions.
// Accessible to account administrators for auditing and session management.

import (
	"net/http"
	"strconv"

	"github.com/gin-gonic/gin"

	"github.com/gochat/gochat/internal/auth"
	"github.com/gochat/gochat/pkg/response"
	applogger "github.com/gochat/gochat/pkg/logger"
)

// SSOSessionHandler handles SSO session management endpoints.
type SSOSessionHandler struct {
	sessionStore *auth.SSOSessionStore
}

// NewSSOSessionHandler creates a new SSOSession handler.
func NewSSOSessionHandler(sessionStore *auth.SSOSessionStore) *SSOSessionHandler {
	return &SSOSessionHandler{sessionStore: sessionStore}
}

// ListByUser returns all active SSO sessions for a user.
// GET /api/v1/sso/sessions?user_id=123
// Admin-only: lists all SSO sessions for a given user across all providers.
func (h *SSOSessionHandler) ListByUser(c *gin.Context) {
	userIDStr := c.Query("user_id")
	if userIDStr == "" {
		c.JSON(http.StatusBadRequest, response.APIResponse{
			Success: false,
			Error: &response.ErrorBody{
				Code:    response.ErrBadRequest,
				Message: "Missing user_id parameter",
			},
		})
		return
	}

	userID, err := strconv.ParseUint(userIDStr, 10, 64)
	if err != nil {
		c.JSON(http.StatusBadRequest, response.APIResponse{
			Success: false,
			Error: &response.ErrorBody{
				Code:    response.ErrBadRequest,
				Message: "Invalid user_id",
			},
		})
		return
	}

	sessions, err := h.sessionStore.GetByUser(c.Request.Context(), uint(userID))
	if err != nil {
		applogger.L().Errorf("Get SSO sessions for user %d: %v", userID, err)
		response.AbortWithStatusError(c, http.StatusInternalServerError, response.ErrInternal, "failed to get SSO sessions")
		return
	}

	c.JSON(http.StatusOK, response.APIResponse{
		Success: true,
		Data:    sessions,
	})
}

// Get retrieves a single SSO session by session ID.
// GET /api/v1/sso/sessions/:session_id
func (h *SSOSessionHandler) Get(c *gin.Context) {
	sessionID := c.Param("session_id")
	if sessionID == "" {
		c.JSON(http.StatusBadRequest, response.APIResponse{
			Success: false,
			Error: &response.ErrorBody{
				Code:    response.ErrBadRequest,
				Message: "Missing session_id",
			},
		})
		return
	}

	session, err := h.sessionStore.Get(c.Request.Context(), sessionID)
	if err != nil {
		applogger.L().Errorf("Get SSO session %s: %v", sessionID, err)
		response.AbortWithStatusError(c, http.StatusInternalServerError, response.ErrInternal, "failed to get SSO session")
		return
	}

	if session == nil {
		c.JSON(http.StatusNotFound, response.APIResponse{
			Success: false,
			Error: &response.ErrorBody{
				Code:    response.ErrNotFound,
				Message: "SSO session not found or expired",
			},
		})
		return
	}

	c.JSON(http.StatusOK, response.APIResponse{
		Success: true,
		Data:    session,
	})
}

// Terminate removes a single SSO session.
// DELETE /api/v1/sso/sessions/:session_id
// Used for manual session termination (admin action).
func (h *SSOSessionHandler) Terminate(c *gin.Context) {
	sessionID := c.Param("session_id")
	if sessionID == "" {
		c.JSON(http.StatusBadRequest, response.APIResponse{
			Success: false,
			Error: &response.ErrorBody{
				Code:    response.ErrBadRequest,
				Message: "Missing session_id",
			},
		})
		return
	}

	terminated, err := h.sessionStore.Terminate(c.Request.Context(), sessionID)
	if err != nil {
		applogger.L().Errorf("Terminate SSO session %s: %v", sessionID, err)
		response.AbortWithStatusError(c, http.StatusInternalServerError, response.ErrInternal, "failed to terminate SSO session")
		return
	}

	if !terminated {
		c.JSON(http.StatusNotFound, response.APIResponse{
			Success: false,
			Error: &response.ErrorBody{
				Code:    response.ErrNotFound,
				Message: "SSO session not found or already expired",
			},
		})
		return
	}

	c.JSON(http.StatusOK, response.APIResponse{
		Success: true,
		Data: map[string]string{
			"session_id": sessionID,
			"status":     "terminated",
		},
	})
}

// TerminateAllByUser terminates all SSO sessions for a user.
// POST /api/v1/sso/sessions/terminate_all?user_id=123
// Used for full user logout — terminates all SSO sessions across all providers.
func (h *SSOSessionHandler) TerminateAllByUser(c *gin.Context) {
	userIDStr := c.Query("user_id")
	if userIDStr == "" {
		c.JSON(http.StatusBadRequest, response.APIResponse{
			Success: false,
			Error: &response.ErrorBody{
				Code:    response.ErrBadRequest,
				Message: "Missing user_id parameter",
			},
		})
		return
	}

	userID, err := strconv.ParseUint(userIDStr, 10, 64)
	if err != nil {
		c.JSON(http.StatusBadRequest, response.APIResponse{
			Success: false,
			Error: &response.ErrorBody{
				Code:    response.ErrBadRequest,
				Message: "Invalid user_id",
			},
		})
		return
	}

	count, err := h.sessionStore.TerminateUserSessions(c.Request.Context(), uint(userID))
	if err != nil {
		applogger.L().Errorf("Terminate all SSO sessions for user %d: %v", userID, err)
		response.AbortWithStatusError(c, http.StatusInternalServerError, response.ErrInternal, "failed to terminate all SSO sessions")
		return
	}

	c.JSON(http.StatusOK, response.APIResponse{
		Success: true,
		Data: map[string]interface{}{
			"user_id":       userID,
			"terminated":    count,
			"status":        "all_sessions_terminated",
		},
	})
}

// CountByUser returns the count of active SSO sessions for a user.
// GET /api/v1/sso/sessions/count?user_id=123
func (h *SSOSessionHandler) CountByUser(c *gin.Context) {
	userIDStr := c.Query("user_id")
	if userIDStr == "" {
		c.JSON(http.StatusBadRequest, response.APIResponse{
			Success: false,
			Error: &response.ErrorBody{
				Code:    response.ErrBadRequest,
				Message: "Missing user_id parameter",
			},
		})
		return
	}

	userID, err := strconv.ParseUint(userIDStr, 10, 64)
	if err != nil {
		c.JSON(http.StatusBadRequest, response.APIResponse{
			Success: false,
			Error: &response.ErrorBody{
				Code:    response.ErrBadRequest,
				Message: "Invalid user_id",
			},
		})
		return
	}

	count, err := h.sessionStore.CountByUser(c.Request.Context(), uint(userID))
	if err != nil {
		applogger.L().Errorf("Count SSO sessions for user %d: %v", userID, err)
		response.AbortWithStatusError(c, http.StatusInternalServerError, response.ErrInternal, "failed to count SSO sessions")
		return
	}

	c.JSON(http.StatusOK, response.APIResponse{
		Success: true,
		Data: map[string]interface{}{
			"user_id": userID,
			"count":   count,
		},
	})
}

// RegisterSSOSessionRoutes maps SSO session management routes.
// All routes require authentication (applied by the router, not here).
// Reference: Chatwoot SsoSession management — user-scoped session auditing
func RegisterSSOSessionRoutes(g *gin.RouterGroup, h *SSOSessionHandler) {
	g.GET("/user/:user_id", h.ListByUser)
	g.GET("/user/:user_id/count", h.CountByUser)
	g.GET("/:session_id", h.Get)
	g.POST("/:session_id/terminate", h.Terminate)
	g.POST("/user/:user_id/terminate_all", h.TerminateAllByUser)
}