package handler

import (
	"encoding/json"
	"errors"
	"fmt"
	"io"
	"net/http"
	"net/http/httptest"
	"testing"

	"github.com/Tencent/WeKnora/internal/application/service"
	apperrors "github.com/Tencent/WeKnora/internal/errors"
	"github.com/Tencent/WeKnora/internal/middleware"
	"github.com/gin-gonic/gin"
)

func TestEmbedManagementErrorMapping(t *testing.T) {
	gin.SetMode(gin.TestMode)
	tests := []struct {
		name    string
		err     error
		status  int
		message string
	}{
		{"forbidden", apperrors.NewForbiddenError("owner or admin required"), http.StatusForbidden, "owner or admin required"},
		{"wrapped forbidden", fmt.Errorf("list: %w", apperrors.NewForbiddenError("owner or admin required")), http.StatusForbidden, "owner or admin required"},
		{"agent missing", service.ErrAgentNotFound, http.StatusNotFound, "agent not found"},
		{"wrapped agent missing", fmt.Errorf("list: %w", service.ErrAgentNotFound), http.StatusNotFound, "agent not found"},
		{"channel missing", service.ErrEmbedChannelNotFound, http.StatusNotFound, "embed channel not found"},
		{"typed missing", apperrors.NewNotFoundError("agent not found"), http.StatusNotFound, "agent not found"},
		{"validation", apperrors.NewBadRequestError("agent_id is required"), http.StatusBadRequest, "agent_id is required"},
		{"unexpected failure", errors.New("database credentials must stay private"), http.StatusInternalServerError, "operation failed"},
		{"internal app failure", apperrors.NewInternalServerError("private failure details"), http.StatusInternalServerError, "operation failed"},
	}
	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			router := gin.New()
			router.Use(middleware.ErrorHandler())
			var observedStatus int
			var recorded error
			router.Use(func(c *gin.Context) {
				c.Next()
				observedStatus = c.Writer.Status()
				if c.Errors.Last() != nil {
					recorded = c.Errors.Last().Err
				}
			})
			router.GET("/agents/agent-1/embed-channels", func(c *gin.Context) {
				writeEmbedMgmtError(c, tt.err)
			})
			writer := httptest.NewRecorder()
			router.ServeHTTP(writer, httptest.NewRequest(http.MethodGet, "/agents/agent-1/embed-channels", nil))
			if writer.Code != tt.status || observedStatus != tt.status {
				t.Fatalf("response status %d, audit status %d, want %d", writer.Code, observedStatus, tt.status)
			}
			var appErr *apperrors.AppError
			if !errors.As(recorded, &appErr) || appErr.Message != tt.message {
				t.Fatalf("unexpected audit error: %v", recorded)
			}
			var body struct {
				Error struct {
					Message string `json:"message"`
				} `json:"error"`
			}
			decoder := json.NewDecoder(writer.Body)
			if err := decoder.Decode(&body); err != nil || body.Error.Message != tt.message {
				t.Fatalf("invalid response: %v, %#v", err, body)
			}
			var extra any
			if err := decoder.Decode(&extra); err != io.EOF {
				t.Fatalf("error middleware wrote more than one response: %v", err)
			}
		})
	}
}