package handlers

import (
	"encoding/json"
	"reflect"
	"strings"
	"testing"

	pluginv1 "github.com/Silo-Server/silo-plugin-sdk/pkg/pluginproto/silo/plugin/v1"
)

// TestAdminFormToJSONSchemaFields locks the bridge between the SDK proto
// AdminForm descriptor and the JSON the frontend SchemaForm consumes. Without
// this, the schema-driven request-connection form silently loses its
// dynamic dropdowns (dynamic_options), conditional visibility (show_when),
// validation, sections, and the MULTI_SELECT control mapping, which makes the
// new form non-functional (required fields can never be set, save stays
// disabled).
func TestAdminFormToJSONSchemaFields(t *testing.T) {
	descriptor := &pluginv1.AdminFormDescriptor{
		SubmitLabel: "Connect",
		Fields: []*pluginv1.AdminFormField{
			{
				Key:                 "quality_profile_ids",
				Label:               "Quality Profiles",
				Control:             pluginv1.AdminFormControl_ADMIN_FORM_CONTROL_MULTI_SELECT,
				DynamicOptions:      true,
				ExclusiveGroupField: "service_kind",
				ShowWhen: []*pluginv1.AdminFormCondition{
					{Field: "service_type", Equals: []string{"radarr", "sonarr"}},
				},
				Validation: &pluginv1.AdminFormValidation{
					HasMin:    true,
					Min:       1,
					HasMax:    true,
					Max:       10,
					Pattern:   "^[0-9]+$",
					MinLength: 1,
					MaxLength: 64,
				},
			},
		},
		Sections: []*pluginv1.AdminFormSection{
			{
				Key:              "advanced",
				Title:            "Advanced",
				Description:      "Optional tuning",
				Collapsible:      true,
				CollapsedDefault: true,
				FieldKeys:        []string{"quality_profile_ids"},
				ShowWhen: []*pluginv1.AdminFormCondition{
					{Field: "service_type", Equals: []string{"radarr"}},
				},
			},
		},
	}

	form := adminFormToJSON(descriptor)
	if form == nil {
		t.Fatal("adminFormToJSON returned nil")
	}

	raw, err := json.Marshal(form)
	if err != nil {
		t.Fatalf("marshal admin form: %v", err)
	}

	var decoded struct {
		Fields []struct {
			Control        string `json:"control"`
			DynamicOptions bool   `json:"dynamic_options"`
			ShowWhen       []struct {
				Field  string   `json:"field"`
				Equals []string `json:"equals"`
			} `json:"show_when"`
			Validation *struct {
				HasMin    bool    `json:"has_min"`
				Min       float64 `json:"min"`
				HasMax    bool    `json:"has_max"`
				Max       float64 `json:"max"`
				Pattern   string  `json:"pattern"`
				MinLength int32   `json:"min_length"`
				MaxLength int32   `json:"max_length"`
			} `json:"validation"`
			ExclusiveGroupField string `json:"exclusive_group_field"`
		} `json:"fields"`
		Sections []struct {
			Key              string   `json:"key"`
			Title            string   `json:"title"`
			Description      string   `json:"description"`
			Collapsible      bool     `json:"collapsible"`
			CollapsedDefault bool     `json:"collapsed_default"`
			FieldKeys        []string `json:"field_keys"`
			ShowWhen         []struct {
				Field  string   `json:"field"`
				Equals []string `json:"equals"`
			} `json:"show_when"`
		} `json:"sections"`
	}
	if err := json.Unmarshal(raw, &decoded); err != nil {
		t.Fatalf("unmarshal admin form: %v\njson: %s", err, raw)
	}

	if len(decoded.Fields) != 1 {
		t.Fatalf("expected 1 field, got %d", len(decoded.Fields))
	}
	field := decoded.Fields[0]

	// Control must serialize to the SHORT form the frontend switches on.
	if field.Control != "MULTI_SELECT" {
		t.Errorf("control = %q, want %q", field.Control, "MULTI_SELECT")
	}
	if !field.DynamicOptions {
		t.Error("dynamic_options = false, want true")
	}
	if field.ExclusiveGroupField != "service_kind" {
		t.Errorf("exclusive_group_field = %q, want %q", field.ExclusiveGroupField, "service_kind")
	}
	if len(field.ShowWhen) != 1 || field.ShowWhen[0].Field != "service_type" ||
		len(field.ShowWhen[0].Equals) != 2 {
		t.Errorf("field show_when not serialized correctly: %+v", field.ShowWhen)
	}
	if field.Validation == nil {
		t.Fatal("validation not serialized")
	}
	if !field.Validation.HasMin || field.Validation.Min != 1 ||
		!field.Validation.HasMax || field.Validation.Max != 10 ||
		field.Validation.Pattern != "^[0-9]+$" ||
		field.Validation.MinLength != 1 || field.Validation.MaxLength != 64 {
		t.Errorf("validation not serialized correctly: %+v", field.Validation)
	}

	if len(decoded.Sections) != 1 {
		t.Fatalf("expected 1 section, got %d", len(decoded.Sections))
	}
	section := decoded.Sections[0]
	if section.Key != "advanced" || section.Title != "Advanced" ||
		section.Description != "Optional tuning" || !section.Collapsible ||
		!section.CollapsedDefault {
		t.Errorf("section scalar fields not serialized correctly: %+v", section)
	}
	if len(section.FieldKeys) != 1 || section.FieldKeys[0] != "quality_profile_ids" {
		t.Errorf("section field_keys not serialized correctly: %+v", section.FieldKeys)
	}
	if len(section.ShowWhen) != 1 || section.ShowWhen[0].Field != "service_type" ||
		len(section.ShowWhen[0].Equals) != 1 {
		t.Errorf("section show_when not serialized correctly: %+v", section.ShowWhen)
	}
}

// adminFormDTOMappingRenames records intentional proto-field -> DTO-field name
// renames. The DTO field names currently mirror the proto field names 1:1, so
// this is empty; add an entry only when a DTO field is deliberately named
// differently from its proto source (the test then accepts the renamed target).
var adminFormDTOMappingRenames = map[string]string{}

// protoInternalFields are the protobuf-runtime bookkeeping fields every
// generated message struct carries. They are never serialized to the client
// DTO, so the completeness guard skips them.
var protoInternalFields = map[string]bool{
	"state":         true,
	"sizeCache":     true,
	"unknownFields": true,
}

// TestAdminFormDTOCompleteness is a guard against the C1-class bug: the
// hand-written adminFormToJSON allowlist (pluginAdminFormFieldJSON /
// pluginAdminFormSectionJSON / pluginAdminFormJSON) silently dropping a NEW
// proto field added to AdminFormField / AdminFormDescriptor / AdminFormSection
// later. It reflects over each proto message's exported fields and asserts the
// corresponding JSON DTO struct has a field mapping to it (by identical Go name,
// or via an explicit rename in adminFormDTOMappingRenames). When the next proto
// field lands, this FAILS naming the un-mapped field, forcing the serializer +
// DTO to be updated in lockstep. (We deliberately do not switch the serializer
// to protojson — the short-form control-string MULTI_SELECT mapping makes that
// risky; this guard is the proportionate fix.)
func TestAdminFormDTOCompleteness(t *testing.T) {
	cases := []struct {
		name  string
		proto reflect.Type
		dto   reflect.Type
	}{
		{"AdminFormField", reflect.TypeOf(pluginv1.AdminFormField{}), reflect.TypeOf(pluginAdminFormFieldJSON{})},
		{"AdminFormDescriptor", reflect.TypeOf(pluginv1.AdminFormDescriptor{}), reflect.TypeOf(pluginAdminFormJSON{})},
		{"AdminFormSection", reflect.TypeOf(pluginv1.AdminFormSection{}), reflect.TypeOf(pluginAdminFormSectionJSON{})},
	}

	for _, tc := range cases {
		t.Run(tc.name, func(t *testing.T) {
			dtoFields := map[string]bool{}
			for i := 0; i < tc.dto.NumField(); i++ {
				dtoFields[tc.dto.Field(i).Name] = true
			}

			for i := 0; i < tc.proto.NumField(); i++ {
				pf := tc.proto.Field(i)
				if !pf.IsExported() {
					continue // unexported protobuf-internal state
				}
				if protoInternalFields[pf.Name] || strings.HasPrefix(pf.Name, "XXX_") {
					continue
				}
				want := pf.Name
				if mapped, ok := adminFormDTOMappingRenames[pf.Name]; ok {
					want = mapped
				}
				if !dtoFields[want] {
					t.Errorf("proto field %s.%s has no corresponding field %q in the JSON DTO %s; "+
						"adminFormToJSON would silently drop it. Add the field to the DTO + serializer "+
						"(or record an intentional rename in adminFormDTOMappingRenames).",
						tc.name, pf.Name, want, tc.dto.Name())
				}
			}
		})
	}
}