package server

import (
	"encoding/json"
	"net/http"
	"net/http/httptest"
	"testing"

	"chat-agent-system/internal/docgov"
	"chat-agent-system/internal/docrevision"
)

func TestWriteControlledContentError_MapsTypedCodes(t *testing.T) {
	cases := []struct {
		err    error
		status int
		code   string
	}{
		{&docgov.ContentError{Code: docgov.ErrCodeDocumentNotFound, Message: "missing record"}, http.StatusNotFound, docgov.ErrCodeDocumentNotFound},
		{&docgov.ContentError{Code: docgov.ErrCodeProjectionMissing, Message: "no file", NeedsAdmin: true, Retryable: true}, http.StatusConflict, docgov.ErrCodeProjectionMissing},
		{&docgov.ContentError{Code: docgov.ErrCodeProjectionEmpty, Message: "empty", NeedsAdmin: true}, http.StatusConflict, docgov.ErrCodeProjectionEmpty},
		{&docgov.ContentError{Code: docgov.ErrCodeIntegrityMismatch, Message: "mismatch", NeedsAdmin: true}, http.StatusConflict, docgov.ErrCodeIntegrityMismatch},
		{&docgov.ContentError{Code: docgov.ErrCodeProjectionDrift, Message: "drift", NeedsAdmin: true, Class: "LEGACY_CANONICALIZATION_DRIFT"}, http.StatusConflict, docgov.ErrCodeProjectionDrift},
	}
	for _, tc := range cases {
		rec := httptest.NewRecorder()
		req := httptest.NewRequest(http.MethodGet, "/api/v1/docgov/documents/x/content", nil)
		req.Header.Set("X-Request-ID", "corr-1")
		writeControlledContentError(rec, req, tc.err)
		if rec.Code != tc.status {
			t.Fatalf("%s status %d want %d", tc.code, rec.Code, tc.status)
		}
		var body map[string]any
		if err := json.Unmarshal(rec.Body.Bytes(), &body); err != nil {
			t.Fatal(err)
		}
		if body["error_code"] != tc.code {
			t.Fatalf("code %v", body["error_code"])
		}
		if body["correlation_id"] != "corr-1" {
			t.Fatalf("correlation %v", body["correlation_id"])
		}
		if tc.err.(*docgov.ContentError).Class != "" && body["projection_class"] != tc.err.(*docgov.ContentError).Class {
			t.Fatalf("projection_class %v", body["projection_class"])
		}
	}
}

func TestServeLedgerHeadOrConflict_ServesLedgerOnDrift(t *testing.T) {
	raw := "条目一  \n条目二  \n"
	head := docrevision.LegacyDestructiveCanonicalizeMarkdown(raw)
	class := docrevision.ClassifyProjection([]byte(raw), head)
	if class.Class != docrevision.ProjectionLegacyCanonicalizationDrift {
		t.Fatalf("class=%s", class.Class)
	}
	gotDrift, err := serveLedgerHeadOrConflict("doc_x", 1, false, head, docrevision.SHA256Hex(head), docrevision.SHA256Hex(head), class)
	if err != nil {
		t.Fatal(err)
	}
	if gotDrift.Consistency != "drift" || gotDrift.Markdown != head {
		t.Fatalf("drift must still serve ledger: %+v", gotDrift)
	}

	aligned := docrevision.ClassifyProjection([]byte(raw), docrevision.CanonicalizeMarkdown(raw))
	got, err := serveLedgerHeadOrConflict("doc_x", 1, false, docrevision.CanonicalizeMarkdown(raw), aligned.CanonSHA, aligned.CanonSHA, aligned)
	if err != nil {
		t.Fatal(err)
	}
	if got.Markdown != docrevision.CanonicalizeMarkdown(raw) {
		t.Fatalf("aligned must serve preserved-hard-break head, got %q", got.Markdown)
	}
}