package service

import (
	"bytes"
	"regexp"
	"strings"
	"testing"

	"github.com/DATA-DOG/go-sqlmock"
	"github.com/wmms/wmms/pkg/database"
)

const importCategoryQuery = `SELECT id, organization_id, code, name, description, parent_id, status FROM material_categories WHERE organization_id = ? ORDER BY code`
const importUnitQuery = `SELECT id, organization_id, code, name, precision_scale, status FROM units WHERE organization_id = ? ORDER BY code`
const importRuleQuery = `SELECT id, organization_id, category_id, prefix, sequence_length, next_sequence, status FROM code_rules WHERE organization_id = ? AND category_id = ? AND status = 'active'`

func newImportServiceMock(t *testing.T) (sqlmock.Sqlmock, func()) {
	t.Helper()
	db, mock, err := sqlmock.New()
	if err != nil {
		t.Fatalf("open sql mock: %v", err)
	}
	previous := database.DB
	database.DB = db
	return mock, func() {
		database.DB = previous
		db.Close()
	}
}

func expectImportMasterData(mock sqlmock.Sqlmock, withRule bool) {
	mock.ExpectQuery(regexp.QuoteMeta(importCategoryQuery)).WithArgs(int64(1)).
		WillReturnRows(sqlmock.NewRows([]string{"id", "organization_id", "code", "name", "description", "parent_id", "status"}).
			AddRow(3, 1, "A", "机械结构类", "", nil, "active").
			AddRow(12, 1, "A01", "标准件", "", 3, "active"))
	mock.ExpectQuery(regexp.QuoteMeta(importUnitQuery)).WithArgs(int64(1)).
		WillReturnRows(sqlmock.NewRows([]string{"id", "organization_id", "code", "name", "precision_scale", "status"}).
			AddRow(1, 1, "个", "个", 0, "active"))
	if withRule {
		mock.ExpectQuery(regexp.QuoteMeta(importRuleQuery)).WithArgs(int64(1), int64(12)).
			WillReturnRows(sqlmock.NewRows([]string{"id", "organization_id", "category_id", "prefix", "sequence_length", "next_sequence", "status"}).
				AddRow(5, 1, 12, "A01", 4, 201, "active"))
	} else {
		mock.ExpectQuery(regexp.QuoteMeta(importRuleQuery)).WithArgs(int64(1), int64(12)).
			WillReturnRows(sqlmock.NewRows([]string{"id", "organization_id", "category_id", "prefix", "sequence_length", "next_sequence"}))
	}
}

// reason 用 interface{}：成功场景断言具体空串，失败场景传 sqlmock.AnyArg()
// 表示只校验"写了一条记录"，不锁死文案。
func expectImportLog(mock sqlmock.Sqlmock, fileName, status string, total, success, failed int, reason interface{}) {
	// 行数显式转 int64：database/sql 会把实参归一成 driver.Value（int→int64），
	// sqlmock 按类型比对，传 Go int 匹配不上。
	mock.ExpectExec(regexp.QuoteMeta(`INSERT INTO material_import_logs (organization_id, operator, file_name, total_rows, success_rows, failed_rows, status, failure_reason) VALUES (?, ?, ?, ?, ?, ?, ?, ?)`)).
		WithArgs(int64(1), "tester", fileName, int64(total), int64(success), int64(failed), status, reason).
		WillReturnResult(sqlmock.NewResult(9, 1))
}

func TestMaterialImportServiceReportsRowErrorsWithoutWritingMaterials(t *testing.T) {
	mock, cleanup := newImportServiceMock(t)
	defer cleanup()

	expectImportMasterData(mock, true)
	expectImportLog(mock, "物料.xlsx", "failed", 2, 0, 2, sqlmock.AnyArg())

	data := buildTestWorkbook(t, [][]string{
		{"", "", "", "机械结构类", "标准件"},    // 名称缺失
		{"螺栓", "", "吨", "不存在的类", "标准件"}, // 大类不存在
	})
	result, err := NewMaterialImportService().Import(1, "tester", "物料.xlsx", bytes.NewReader(data))
	if err != nil {
		t.Fatalf("import: %v", err)
	}
	if result.SuccessRows != 0 || result.FailedRows != 2 || len(result.Errors) != 2 {
		t.Fatalf("result = %+v", result)
	}
	if result.Errors[0].Row != 2 || !strings.Contains(result.Errors[0].Reason, "物料名称") {
		t.Fatalf("first error = %+v", result.Errors[0])
	}
	if result.Errors[1].Row != 3 || !strings.Contains(result.Errors[1].Reason, "大类") {
		t.Fatalf("second error = %+v", result.Errors[1])
	}
	if err := mock.ExpectationsWereMet(); err != nil {
		t.Fatal(err)
	}
}

func TestMaterialImportServiceReportsMissingCodeRule(t *testing.T) {
	mock, cleanup := newImportServiceMock(t)
	defer cleanup()

	expectImportMasterData(mock, false)
	expectImportLog(mock, "物料.xlsx", "failed", 1, 0, 1, sqlmock.AnyArg())

	data := buildTestWorkbook(t, [][]string{
		{"螺栓", "", "个", "机械结构类", "标准件"},
	})
	result, err := NewMaterialImportService().Import(1, "tester", "物料.xlsx", bytes.NewReader(data))
	if err != nil {
		t.Fatalf("import: %v", err)
	}
	if result.FailedRows != 1 || !strings.Contains(result.Errors[0].Reason, "编码规则") {
		t.Fatalf("result = %+v", result)
	}
	if err := mock.ExpectationsWereMet(); err != nil {
		t.Fatal(err)
	}
}

func TestMaterialImportServiceRejectsInvalidTemplate(t *testing.T) {
	mock, cleanup := newImportServiceMock(t)
	defer cleanup()

	expectImportLog(mock, "错的.xlsx", "failed", 0, 0, 0, sqlmock.AnyArg())

	result, err := NewMaterialImportService().Import(1, "tester", "错的.xlsx", strings.NewReader("not an xlsx"))
	if err == nil {
		t.Fatal("期望返回模板错误")
	}
	if result != nil {
		t.Fatalf("result = %+v, want nil", result)
	}
	if err := mock.ExpectationsWereMet(); err != nil {
		t.Fatal(err)
	}
}

func TestMaterialImportServiceImportsWhenAllRowsValid(t *testing.T) {
	mock, cleanup := newImportServiceMock(t)
	defer cleanup()

	expectImportMasterData(mock, true)
	// 事务内：锁规则 → 取已占用编码 → 推进序号 → 插入 → 回查 ID
	// ImportTx 先把整批编码分配完并推进 code_rules，再分批插入。
	mock.ExpectBegin()
	mock.ExpectQuery(regexp.QuoteMeta(`SELECT id, organization_id, category_id, prefix, sequence_length, next_sequence FROM code_rules WHERE organization_id = ? AND category_id = ? AND status = 'active' FOR UPDATE`)).
		WithArgs(int64(1), int64(12)).
		WillReturnRows(sqlmock.NewRows([]string{"id", "organization_id", "category_id", "prefix", "sequence_length", "next_sequence"}).
			AddRow(5, 1, 12, "A01", 4, 201))
	mock.ExpectQuery(`SELECT material_code FROM materials WHERE organization_id = \? AND material_code LIKE \?`).
		WithArgs(int64(1), "A01%").
		WillReturnRows(sqlmock.NewRows([]string{"material_code"}))
	mock.ExpectExec(regexp.QuoteMeta(`UPDATE code_rules SET next_sequence = ? WHERE id = ?`)).
		WithArgs(int64(202), int64(5)).WillReturnResult(sqlmock.NewResult(0, 1))
	mock.ExpectExec(`INSERT INTO materials`).WillReturnResult(sqlmock.NewResult(31, 1))
	mock.ExpectQuery(`SELECT id, material_code FROM materials WHERE organization_id = \? AND material_code IN \(\?\)`).
		WithArgs(int64(1), "A010201").
		WillReturnRows(sqlmock.NewRows([]string{"id", "material_code"}).AddRow(31, "A010201"))
	mock.ExpectExec(`INSERT INTO material_logs`).WillReturnResult(sqlmock.NewResult(1, 1))
	mock.ExpectCommit()
	expectImportLog(mock, "物料.xlsx", "success", 1, 1, 0, "")

	data := buildTestWorkbook(t, [][]string{
		{"内六角螺栓", "M8x30", "个", "机械结构类", "标准件"},
	})
	result, err := NewMaterialImportService().Import(1, "tester", "物料.xlsx", bytes.NewReader(data))
	if err != nil {
		t.Fatalf("import: %v", err)
	}
	if result.SuccessRows != 1 || result.FailedRows != 0 || len(result.Errors) != 0 {
		t.Fatalf("result = %+v", result)
	}
	if err := mock.ExpectationsWereMet(); err != nil {
		t.Fatal(err)
	}
}

func TestMaterialImportServiceRollsBackWhenInsertFails(t *testing.T) {
	mock, cleanup := newImportServiceMock(t)
	defer cleanup()

	expectImportMasterData(mock, true)
	mock.ExpectBegin()
	mock.ExpectQuery(`FOR UPDATE`).WillReturnRows(sqlmock.NewRows([]string{"id", "organization_id", "category_id", "prefix", "sequence_length", "next_sequence"}).
		AddRow(5, 1, 12, "A01", 4, 201))
	mock.ExpectQuery(`SELECT material_code FROM materials`).WillReturnRows(sqlmock.NewRows([]string{"material_code"}))
	mock.ExpectExec(regexp.QuoteMeta(`UPDATE code_rules SET next_sequence = ? WHERE id = ?`)).WillReturnResult(sqlmock.NewResult(0, 1))
	mock.ExpectExec(`INSERT INTO materials`).WillReturnResult(sqlmock.NewResult(0, 0))
	// 插入后回查不到 ID（模拟插入未真正落库），persist 据此报错并回滚
	mock.ExpectQuery(`SELECT id, material_code FROM materials`).WillReturnRows(sqlmock.NewRows([]string{"id", "material_code"}))
	mock.ExpectRollback()
	expectImportLog(mock, "物料.xlsx", "failed", 1, 0, 1, sqlmock.AnyArg())

	data := buildTestWorkbook(t, [][]string{
		{"内六角螺栓", "M8x30", "个", "机械结构类", "标准件"},
	})
	result, err := NewMaterialImportService().Import(1, "tester", "物料.xlsx", bytes.NewReader(data))
	if err == nil {
		t.Fatal("期望入库失败")
	}
	if result != nil {
		t.Fatalf("result = %+v, want nil", result)
	}
	if err := mock.ExpectationsWereMet(); err != nil {
		t.Fatal(err)
	}
}