package apierror

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

func TestFromErrorPassesThroughProblem(t *testing.T) {
	original := Problem{Title: "Teapot", Status: 418, Code: "TEAPOT"}
	got := FromError(original)
	if got != original {
		t.Errorf("FromError(Problem) lost data: got %+v want %+v", got, original)
	}
}

func TestFromErrorWrappedProblem(t *testing.T) {
	original := Problem{Title: "Teapot", Status: 418}
	wrapped := fmt.Errorf("outer: %w", original)
	got := FromError(wrapped)
	if got.Status != 418 {
		t.Errorf("status = %d, want 418", got.Status)
	}
}

func TestFromErrorNotFound(t *testing.T) {
	p := FromError(NotFound("widget"))
	if p.Status != 404 {
		t.Errorf("status = %d, want 404", p.Status)
	}
	if p.Code != "NOT_FOUND" {
		t.Errorf("code = %q", p.Code)
	}
	if p.Detail != "widget not found" {
		t.Errorf("detail = %q", p.Detail)
	}
}

func TestFromErrorBadRequest(t *testing.T) {
	p := FromError(BadRequest("missing q"))
	if p.Status != 400 {
		t.Errorf("status = %d, want 400", p.Status)
	}
	if p.Code != "BAD_REQUEST" {
		t.Errorf("code = %q", p.Code)
	}
	if p.Detail != "missing q" {
		t.Errorf("detail = %q", p.Detail)
	}
}

func TestFromErrorUnknownCollapsesTo500(t *testing.T) {
	p := FromError(errors.New("secret database password leaked"))
	if p.Status != 500 {
		t.Errorf("status = %d, want 500", p.Status)
	}
	if p.Detail != "" {
		t.Errorf("detail should be empty to avoid leaks, got %q", p.Detail)
	}
	if p.Title != "Internal Server Error" {
		t.Errorf("title = %q", p.Title)
	}
}

func TestProblemError(t *testing.T) {
	p := Problem{Title: "Bad"}
	if p.Error() != "Bad" {
		t.Errorf("Error() = %q", p.Error())
	}
}

func TestProblemWrite(t *testing.T) {
	rr := httptest.NewRecorder()
	p := Problem{Title: "Not Found", Status: 404, Detail: "thing missing", Code: "NOT_FOUND"}
	p.Write(rr)

	if rr.Code != 404 {
		t.Errorf("status = %d", rr.Code)
	}
	if got := rr.Header().Get("Content-Type"); got != "application/problem+json" {
		t.Errorf("content-type = %q", got)
	}

	var decoded Problem
	if err := json.Unmarshal(rr.Body.Bytes(), &decoded); err != nil {
		t.Fatalf("decode body: %v", err)
	}
	if decoded != p {
		t.Errorf("decoded = %+v, want %+v", decoded, p)
	}
}

func TestNotFoundErrorMessage(t *testing.T) {
	if got := (NotFoundError{Resource: "thing"}).Error(); got != "thing not found" {
		t.Errorf("Error() = %q", got)
	}
}

func TestBadRequestErrorMessage(t *testing.T) {
	if got := (BadRequestError{Detail: "nope"}).Error(); got != "nope" {
		t.Errorf("Error() = %q", got)
	}
}