package main

import (
	"bytes"
	"io"
	"mime/multipart"
	"net/http"
	"net/http/httptest"
	"testing"
)

func postCSV(t *testing.T, mux *http.ServeMux, token, csv string) *httptest.ResponseRecorder {
	t.Helper()
	var buf bytes.Buffer
	writer := multipart.NewWriter(&buf)
	part, _ := writer.CreateFormFile("csv", "attendees.csv")
	io.WriteString(part, csv)
	writer.Close()

	req := httptest.NewRequest("POST", "/api/import", &buf)
	req.Header.Set("Content-Type", writer.FormDataContentType())
	req.Header.Set("Authorization", "Bearer "+token)
	w := httptest.NewRecorder()
	mux.ServeHTTP(w, req)
	return w
}

func TestImportCrowdWorkFormat(t *testing.T) {
	app := testApp(t)
	admin := testAdminUser(t, app)
	token := testToken(t, app, admin)
	mux := testMux(app)

	csv := "Patron Name,Patron Email,Order Number,Tier Name\nAlice,alice@test.com,ORD-1,GA\nBob,bob@test.com,ORD-2,VIP\n"
	w := postCSV(t, mux, token, csv)

	if w.Code != http.StatusOK {
		t.Fatalf("status = %d\nbody: %s", w.Code, w.Body.String())
	}
	result := parseJSON(t, w)
	if result["inserted"] != float64(2) {
		t.Errorf("inserted = %v, want 2", result["inserted"])
	}
}

func TestImportGenericFormat(t *testing.T) {
	app := testApp(t)
	admin := testAdminUser(t, app)
	token := testToken(t, app, admin)
	mux := testMux(app)

	csv := "name,email,ticket_id,ticket_type,note\nAlice,alice@test.com,T1,GA,VIP guest\n"
	w := postCSV(t, mux, token, csv)

	if w.Code != http.StatusOK {
		t.Fatalf("status = %d", w.Code)
	}
	result := parseJSON(t, w)
	if result["inserted"] != float64(1) {
		t.Errorf("inserted = %v", result["inserted"])
	}
}

func TestImportPartySizeDedup(t *testing.T) {
	app := testApp(t)
	admin := testAdminUser(t, app)
	token := testToken(t, app, admin)
	mux := testMux(app)

	// 3 rows same name+order = 1 record, party_size=3
	csv := "Patron Name,Patron Email,Order Number,Tier Name\nAlice,alice@test.com,ORD-1,GA\nAlice,alice@test.com,ORD-1,GA\nAlice,alice@test.com,ORD-1,GA\n"
	w := postCSV(t, mux, token, csv)

	result := parseJSON(t, w)
	if result["inserted"] != float64(1) {
		t.Errorf("inserted = %v, want 1", result["inserted"])
	}
	if result["grouped"] != float64(2) {
		t.Errorf("grouped = %v, want 2", result["grouped"])
	}

	attendees, _ := app.listAttendees("", "", "")
	if len(attendees) != 1 {
		t.Fatalf("attendee count = %d, want 1", len(attendees))
	}
	if attendees[0].PartySize != 3 {
		t.Errorf("party_size = %d, want 3", attendees[0].PartySize)
	}
}

func TestImportReimportSkips(t *testing.T) {
	app := testApp(t)
	admin := testAdminUser(t, app)
	token := testToken(t, app, admin)
	mux := testMux(app)

	csv := "name\nAlice\nBob\n"
	postCSV(t, mux, token, csv)

	// Re-import same data
	w := postCSV(t, mux, token, csv)
	result := parseJSON(t, w)
	if result["inserted"] != float64(0) {
		t.Errorf("re-import inserted = %v, want 0", result["inserted"])
	}
	if result["skipped"] != float64(2) {
		t.Errorf("skipped = %v, want 2", result["skipped"])
	}
}

func TestImportMissingNameColumn(t *testing.T) {
	app := testApp(t)
	admin := testAdminUser(t, app)
	token := testToken(t, app, admin)
	mux := testMux(app)

	csv := "email,phone\nalice@test.com,555-1234\n"
	w := postCSV(t, mux, token, csv)

	if w.Code != http.StatusBadRequest {
		t.Errorf("status = %d, want 400", w.Code)
	}
}

func TestImportBOM(t *testing.T) {
	app := testApp(t)
	admin := testAdminUser(t, app)
	token := testToken(t, app, admin)
	mux := testMux(app)

	// BOM-encoded CSV
	csv := "\xef\xbb\xbfname,email\nAlice,alice@test.com\n"
	w := postCSV(t, mux, token, csv)

	if w.Code != http.StatusOK {
		t.Fatalf("status = %d", w.Code)
	}
	result := parseJSON(t, w)
	if result["inserted"] != float64(1) {
		t.Errorf("inserted = %v, want 1", result["inserted"])
	}
}