package repository

import (
	"regexp"
	"testing"

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

const stockByMaterialSQL = `SELECT m.id, m.material_code, m.name, m.spec, m.unit,
		COALESCE(SUM(ib.on_hand), 0), COALESCE(MAX(swr.minimum_available), 0), COALESCE(MAX(swr.enabled), FALSE),
		MAX(swr.material_id) IS NOT NULL,
		IFNULL(pc.code, ''), IFNULL(c.code, '')
		FROM materials m
		LEFT JOIN inventory_balances ib ON ib.material_id = m.id
		LEFT JOIN stock_warning_rules swr ON swr.organization_id = ib.organization_id
			AND swr.warehouse_id = ib.warehouse_id AND swr.material_id = m.id
		LEFT JOIN material_categories c ON c.id = m.category_id
		LEFT JOIN material_categories pc ON pc.id = c.parent_id
		WHERE m.id = ?
		GROUP BY m.id, m.material_code, m.name, m.spec, m.unit, pc.code, c.code`

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

	mock.ExpectQuery(regexp.QuoteMeta(stockByMaterialSQL)).WithArgs(int64(9)).WillReturnRows(
		sqlmock.NewRows([]string{"id", "material_code", "name", "spec", "unit", "on_hand", "minimum_available", "enabled", "warning_configured", "major_category", "minor_category"}).
			AddRow(9, "MAT-009", "电机", "80W", "台", "12.500000", "3.000000", true, true, "B01", "CAT-SUB-027"),
	)

	stock, err := NewStockRepo().GetByMaterialID(9)
	if err != nil {
		t.Fatalf("get stock: %v", err)
	}
	if !stock.TotalOnHand.Equal(decimal.RequireFromString("12.500000")) || !stock.WarningStock.Equal(decimal.NewFromInt(3)) {
		t.Fatalf("unexpected stock quantities: %+v", stock)
	}
	if !stock.WarningEnabled {
		t.Fatalf("expected warning to read back as enabled: %+v", stock)
	}
	if stock.MajorCategory != "B01" || stock.MinorCategory != "CAT-SUB-027" {
		t.Fatalf("unexpected stock categories: %+v", stock)
	}
	if err := mock.ExpectationsWereMet(); err != nil {
		t.Fatal(err)
	}
}

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

	query := `SELECT COALESCE(SUM(on_hand), 0) FROM inventory_balances WHERE material_id = ?`
	mock.ExpectQuery(regexp.QuoteMeta(query)).WithArgs(int64(9)).WillReturnRows(
		sqlmock.NewRows([]string{"on_hand"}).AddRow("1500.250000"),
	)

	stock, err := NewStockRepo().GetStock(9)
	if err != nil {
		t.Fatalf("get stock: %v", err)
	}
	if !stock.Equal(decimal.RequireFromString("1500.250000")) {
		t.Fatalf("stock = %s, want 1500.250000", stock)
	}
}

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

	mock.ExpectBegin()
	tx, err := db.Begin()
	if err != nil {
		t.Fatalf("begin: %v", err)
	}
	query := `INSERT INTO inventory_balances (organization_id, warehouse_id, location_id, material_id, on_hand)
		SELECT o.id, w.id, l.id, ?, ?
		FROM organizations o
		JOIN warehouses w ON w.organization_id = o.id AND w.code = 'DEFAULT'
		JOIN warehouse_locations l ON l.warehouse_id = w.id AND l.code = 'MAIN'
		WHERE o.code = 'DEFAULT'
		ON DUPLICATE KEY UPDATE on_hand = on_hand + VALUES(on_hand), version = version + 1`
	mock.ExpectExec(regexp.QuoteMeta(query)).WithArgs(int64(11), "5.5").WillReturnResult(sqlmock.NewResult(1, 1))

	if err := NewStockRepo().UpdateStockTx(tx, 11, decimal.RequireFromString("5.500000")); err != nil {
		t.Fatalf("update inventory balance: %v", err)
	}
	if err := mock.ExpectationsWereMet(); err != nil {
		t.Fatal(err)
	}
}

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

	mock.ExpectExec(regexp.QuoteMeta(upsertStockWarningRuleSQL)).
		WithArgs(int64(13), "8.75", true).WillReturnResult(sqlmock.NewResult(1, 1))

	if err := NewStockRepo().UpdateWarningStock(13, decimal.RequireFromString("8.750000"), true); err != nil {
		t.Fatalf("update stock warning: %v", err)
	}
	if err := mock.ExpectationsWereMet(); err != nil {
		t.Fatal(err)
	}
}

// 阈值为 0 是合法配置，含义是"库存降到 0 时预警"，必须原样落库而不是被当成"未设置"。
func TestStockRepoUpdateWarningStockAcceptsZeroThreshold(t *testing.T) {
	db, mock, err := sqlmock.New()
	if err != nil {
		t.Fatalf("open sql mock: %v", err)
	}
	t.Cleanup(func() {
		database.DB = nil
		db.Close()
	})
	database.DB = db

	mock.ExpectExec(regexp.QuoteMeta(upsertStockWarningRuleSQL)).
		WithArgs(int64(13), "0", true).WillReturnResult(sqlmock.NewResult(1, 1))

	if err := NewStockRepo().UpdateWarningStock(13, decimal.Zero, true); err != nil {
		t.Fatalf("update stock warning: %v", err)
	}
	if err := mock.ExpectationsWereMet(); err != nil {
		t.Fatal(err)
	}
}

// 关闭预警时只翻 enabled，阈值本身要原样保留，方便之后重新启用。
func TestStockRepoUpdateWarningStockCanDisableKeepingThreshold(t *testing.T) {
	db, mock, err := sqlmock.New()
	if err != nil {
		t.Fatalf("open sql mock: %v", err)
	}
	t.Cleanup(func() {
		database.DB = nil
		db.Close()
	})
	database.DB = db

	mock.ExpectExec(regexp.QuoteMeta(upsertStockWarningRuleSQL)).
		WithArgs(int64(13), "8.75", false).WillReturnResult(sqlmock.NewResult(1, 1))

	if err := NewStockRepo().UpdateWarningStock(13, decimal.RequireFromString("8.750000"), false); err != nil {
		t.Fatalf("update stock warning: %v", err)
	}
	if err := mock.ExpectationsWereMet(); err != nil {
		t.Fatal(err)
	}
}

// 重复保存同一个阈值时 MySQL 返回 0 影响行，这跟"找不到默认组织/仓库"是两种不同情况，
// 不能把它当成错误报出来。
func TestStockRepoUpdateWarningStockKeepsUnchangedThreshold(t *testing.T) {
	db, mock, err := sqlmock.New()
	if err != nil {
		t.Fatalf("open sql mock: %v", err)
	}
	t.Cleanup(func() {
		database.DB = nil
		db.Close()
	})
	database.DB = db

	mock.ExpectExec(regexp.QuoteMeta(upsertStockWarningRuleSQL)).
		WithArgs(int64(13), "8.75", true).WillReturnResult(sqlmock.NewResult(0, 0))
	mock.ExpectQuery(regexp.QuoteMeta(defaultWarehouseExistsSQL)).
		WillReturnRows(sqlmock.NewRows([]string{"count"}).AddRow(1))

	if err := NewStockRepo().UpdateWarningStock(13, decimal.RequireFromString("8.750000"), true); err != nil {
		t.Fatalf("unchanged threshold must not fail: %v", err)
	}
	if err := mock.ExpectationsWereMet(); err != nil {
		t.Fatal(err)
	}
}

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

	mock.ExpectExec(regexp.QuoteMeta(upsertStockWarningRuleSQL)).
		WithArgs(int64(13), "8.75", true).WillReturnResult(sqlmock.NewResult(0, 0))
	mock.ExpectQuery(regexp.QuoteMeta(defaultWarehouseExistsSQL)).
		WillReturnRows(sqlmock.NewRows([]string{"count"}).AddRow(0))

	if err := NewStockRepo().UpdateWarningStock(13, decimal.RequireFromString("8.750000"), true); err == nil {
		t.Fatal("expected an error when the default organization/warehouse is missing")
	}
	if err := mock.ExpectationsWereMet(); err != nil {
		t.Fatal(err)
	}
}

// 库存列表和它的 COUNT 查询是两条独立 SQL，筛选条件必须同时出现在两边，否则分页总数
// 会和实际行数对不上、末尾多出空白页。
func TestStockRepoGetAllStockFiltersBothCountAndList(t *testing.T) {
	db, mock, err := sqlmock.New()
	if err != nil {
		t.Fatalf("open sql mock: %v", err)
	}
	t.Cleanup(func() {
		database.DB = nil
		db.Close()
	})
	database.DB = db

	filter := regexp.QuoteMeta(stockedMaterialFilterSQL)
	mock.ExpectQuery(`(?s)SELECT COUNT\(\*\) FROM materials m WHERE 1=1.*` + filter).
		WillReturnRows(sqlmock.NewRows([]string{"count"}).AddRow(1))
	mock.ExpectQuery(`(?s)SELECT m\.id, m\.material_code.*`+filter+`.*ORDER BY m\.id LIMIT \? OFFSET \?`).
		WithArgs(20, 0).
		WillReturnRows(sqlmock.NewRows([]string{
			"id", "material_code", "name", "spec", "unit", "on_hand", "minimum_available", "enabled", "warning_configured", "major_category", "minor_category",
		}).AddRow(7, "MAT-007", "轴承", "6204", "个", "4.000000", "10.000000", true, true, "A01", "A01-01"))

	stocks, total, err := NewStockRepo().GetAllStock("", 20, 0)
	if err != nil {
		t.Fatalf("get all stock: %v", err)
	}
	if total != 1 || len(stocks) != 1 {
		t.Fatalf("unexpected result: total=%d stocks=%+v", total, stocks)
	}
	if !stocks[0].WarningStock.Equal(decimal.NewFromInt(10)) || !stocks[0].WarningEnabled {
		t.Fatalf("unexpected warning fields: %+v", stocks[0])
	}
	if err := mock.ExpectationsWereMet(); err != nil {
		t.Fatal(err)
	}
}

// 预警列表同样有 COUNT 和主查询两条 SQL，而且两条都必须带上与 service.ClassifyStock
// 对应的 HAVING 判定。
func TestStockRepoGetWarningStockAppliesThresholdRuleToBothQueries(t *testing.T) {
	db, mock, err := sqlmock.New()
	if err != nil {
		t.Fatalf("open sql mock: %v", err)
	}
	t.Cleanup(func() {
		database.DB = nil
		db.Close()
	})
	database.DB = db

	having := regexp.QuoteMeta(stockWarningHavingSQL)
	mock.ExpectQuery(`(?s)SELECT COUNT\(\*\) FROM \(.*` + having).
		WillReturnRows(sqlmock.NewRows([]string{"count"}).AddRow(1))
	mock.ExpectQuery(`(?s)SELECT m\.id, m\.material_code.*`+having+`.*ORDER BY m\.id LIMIT \? OFFSET \?`).
		WithArgs(20, 0).
		WillReturnRows(sqlmock.NewRows([]string{
			"id", "material_code", "name", "spec", "unit", "on_hand", "minimum_available", "enabled", "warning_configured", "major_category", "minor_category",
		}).AddRow(7, "MAT-007", "轴承", "6204", "个", "0.000000", "10.000000", true, true, "A01", "A01-01"))

	stocks, total, err := NewStockRepo().GetWarningStock(20, 0)
	if err != nil {
		t.Fatalf("get warning stock: %v", err)
	}
	if total != 1 || len(stocks) != 1 {
		t.Fatalf("unexpected result: total=%d stocks=%+v", total, stocks)
	}
	if err := mock.ExpectationsWereMet(); err != nil {
		t.Fatal(err)
	}
}