package middleware

// Reference: P2E §2.7 — RoleCheck middleware
// Simple middleware that verifies the user has the specified role in the current account.
// Used for endpoints that require a specific role regardless of permission dimensions.

import (
	"net/http"

	"github.com/gin-gonic/gin"

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

// RoleCheck creates a middleware that verifies the current user has the specified role.
// This is a simple role gate — for more granular permission checks, use PolicyMiddleware.
//
// Usage:
//   router.POST("/accounts/:id/users", RoleCheck("administrator"), inviteUser)
//   router.GET("/reports", RoleCheck("administrator"), viewReports)
//
// Valid role values: "agent", "administrator", "custom_role"
func RoleCheck(role string) gin.HandlerFunc {
	return func(c *gin.Context) {
		pc, exists := c.Get("policy_context")
		if !exists {
			response.AbortWithStatusError(c, http.StatusForbidden, response.ErrForbidden,
				"Policy context not found — ensure AccountScope middleware is applied first")
			return
		}

		policyCtx, ok := pc.(*auth.PolicyContext)
		if !ok {
			response.AbortWithStatusError(c, http.StatusForbidden, response.ErrForbidden,
				"Invalid policy context type")
			return
		}

		switch role {
		case "administrator":
			if !policyCtx.IsAdministrator() {
				response.AbortWithStatusError(c, http.StatusForbidden, response.ErrForbidden,
					"Administrator role required")
				return
			}
		case "agent":
			if !policyCtx.IsAgent() {
				response.AbortWithStatusError(c, http.StatusForbidden, response.ErrForbidden,
					"Agent role required")
				return
			}
		case "custom_role":
			if !policyCtx.IsCustomRole() {
				response.AbortWithStatusError(c, http.StatusForbidden, response.ErrForbidden,
					"Custom role required")
				return
			}
		default:
			// Check if the user's role matches exactly
			if policyCtx.Role != role {
				response.AbortWithStatusError(c, http.StatusForbidden, response.ErrForbidden,
					"Role '"+role+"' required, but user has role '"+policyCtx.Role+"'")
				return
			}
		}

		c.Next()
	}
}

// RoleCheckAny creates a middleware that verifies the current user has ANY of the specified roles.
// Useful for endpoints accessible to multiple roles.
//
// Usage:
//   router.GET("/dashboard", RoleCheckAny("administrator", "custom_role"), viewDashboard)
func RoleCheckAny(roles ...string) gin.HandlerFunc {
	roleSet := make(map[string]bool, len(roles))
	for _, r := range roles {
		roleSet[r] = true
	}

	return func(c *gin.Context) {
		pc, exists := c.Get("policy_context")
		if !exists {
			response.AbortWithStatusError(c, http.StatusForbidden, response.ErrForbidden,
				"Policy context not found — ensure AccountScope middleware is applied first")
			return
		}

		policyCtx, ok := pc.(*auth.PolicyContext)
		if !ok {
			response.AbortWithStatusError(c, http.StatusForbidden, response.ErrForbidden,
				"Invalid policy context type")
			return
		}

		if !roleSet[policyCtx.Role] {
			response.AbortWithStatusError(c, http.StatusForbidden, response.ErrForbidden,
				"One of the following roles required: "+formatRoles(roles))
			return
		}

		c.Next()
	}
}

func formatRoles(roles []string) string {
	result := ""
	for i, r := range roles {
		if i > 0 {
			result += ", "
		}
		result += r
	}
	return result
}