package handler

import (
	"database/sql"
	"encoding/json"
	"fmt"
	"net/http/httptest"
	"os"
	"path/filepath"
	"strings"
	"testing"
	"time"

	"github.com/gin-gonic/gin"
	"github.com/go-sql-driver/mysql"
	"github.com/wmms/wmms/pkg/database"
)

// TestOrderFlowIsolatesCompanyInventoryMySQL 用一张一次性 MySQL 库做端到端验收：
// A 公司的入库/出库/编辑/删除只改变 A 公司的库存与单据，B 公司完全不受影响；
// 库存不足、仓库停用等失败不会留下半张单据或孤立流水。真实库用例，未配 TEST_DB_DSN 时 skip。
func TestOrderFlowIsolatesCompanyInventoryMySQL(t *testing.T) {
	dsn := os.Getenv("TEST_DB_DSN")
	if dsn == "" {
		t.Skip("real MySQL integration requires TEST_DB_DSN")
	}
	cfg, err := mysql.ParseDSN(dsn)
	if err != nil {
		t.Fatal(err)
	}
	if !strings.HasPrefix(cfg.DBName, "company_isolation_test") {
		t.Fatal("TEST_DB_DSN must name a company_isolation_test schema")
	}
	cfg.DBName = ""
	cfg.MultiStatements = true
	cfg.ParseTime = true
	admin, err := sql.Open("mysql", cfg.FormatDSN())
	if err != nil {
		t.Fatal(err)
	}
	name := fmt.Sprintf("company_isolation_test_order_%d", time.Now().UnixNano())
	if _, err = admin.Exec("CREATE DATABASE `" + name + "` CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci"); err != nil {
		admin.Close()
		t.Fatal(err)
	}
	cfg.DBName = name
	db, err := sql.Open("mysql", cfg.FormatDSN())
	if err != nil {
		admin.Exec("DROP DATABASE `" + name + "`")
		admin.Close()
		t.Fatal(err)
	}
	previous := database.DB
	database.DB = db
	t.Cleanup(func() { database.DB = previous; db.Close(); admin.Exec("DROP DATABASE `" + name + "`"); admin.Close() })

	content, err := os.ReadFile(filepath.Join("..", "..", "scripts", "init.sql"))
	if err != nil {
		t.Fatal(err)
	}
	var lines []string
	for _, line := range strings.Split(strings.TrimPrefix(string(content), "\ufeff"), "\n") {
		if strings.HasPrefix(line, "CREATE DATABASE") || strings.HasPrefix(line, "USE ") {
			continue
		}
		lines = append(lines, line)
	}
	exec := func(query string, args ...interface{}) {
		t.Helper()
		if _, err := db.Exec(query, args...); err != nil {
			t.Fatalf("fixture SQL: %v\n%s", err, query)
		}
	}
	exec(strings.Join(lines, "\n"))
	// 公司 A=201、B=202 各配一组启用仓库、库位与一个物料，余额 A=10、B=50；
	// 用户 7 有 warehouse_admin 角色，并同时被授权公司 A、B。
	exec(`INSERT INTO organizations(id,code,name,status) VALUES (201,'OI_A','公司A','active'),(202,'OI_B','公司B','active');
	 INSERT INTO users(id,username,password) VALUES (7,'order-user','x');
	 INSERT INTO user_roles(user_id,role_id) SELECT 7,id FROM roles WHERE code='warehouse_admin';
	 INSERT INTO user_organizations(user_id,organization_id,is_default) VALUES (7,201,1),(7,202,0);
	 INSERT INTO material_categories(id,organization_id,code,name) VALUES (201,201,'C','C'),(202,202,'C','C');
	 INSERT INTO units(id,organization_id,code,name) VALUES (201,201,'U','U'),(202,202,'U','U');
	 INSERT INTO materials(id,organization_id,material_code,name,spec,unit,category_id,base_unit_id) VALUES (201,201,'MA','A','','pcs',201,201),(202,202,'MB','B','','pcs',202,202);
	 INSERT INTO warehouses(id,organization_id,code,name,status) VALUES (201,201,'W','W','active'),(202,202,'W','W','active');
	 INSERT INTO warehouse_locations(id,warehouse_id,code,name,status) VALUES (201,201,'L','L','active'),(202,202,'L','L','active');
	 INSERT INTO inventory_balances(organization_id,warehouse_id,location_id,material_id,on_hand) VALUES (201,201,201,201,10),(202,202,202,202,50);`)

	token := contextToken(t)
	gin.SetMode(gin.TestMode)
	router := gin.New()
	NewHandler().RegisterRoutes(router)

	request := func(method, path, body string, org int64) *httptest.ResponseRecorder {
		t.Helper()
		req := httptest.NewRequest(method, path, strings.NewReader(body))
		req.Header.Set("Authorization", "Bearer "+token)
		req.Header.Set("X-Organization-ID", fmt.Sprint(org))
		if body != "" {
			req.Header.Set("Content-Type", "application/json")
		}
		w := httptest.NewRecorder()
		router.ServeHTTP(w, req)
		return w
	}
	expectStatus := func(w *httptest.ResponseRecorder, status int) {
		t.Helper()
		if w.Code != status {
			t.Fatalf("status=%d body=%s, want %d", w.Code, w.Body.String(), status)
		}
	}
	balance := func(org, material int64) string {
		t.Helper()
		var onHand string
		if err := db.QueryRow(`SELECT COALESCE(on_hand,0) FROM inventory_balances WHERE organization_id=? AND material_id=?`, org, material).Scan(&onHand); err != nil {
			t.Fatal(err)
		}
		return onHand
	}
	orderCount := func(table string, org int64) int {
		t.Helper()
		var count int
		if err := db.QueryRow(`SELECT COUNT(*) FROM `+table+` WHERE organization_id=?`, org).Scan(&count); err != nil {
			t.Fatal(err)
		}
		return count
	}
	orphanLogs := func(org int64) int {
		t.Helper()
		var count int
		if err := db.QueryRow(`SELECT COUNT(*) FROM stock_logs sl WHERE sl.organization_id=? AND ((sl.related_order_type='inbound' AND sl.related_order_id NOT IN (SELECT id FROM inbound_orders WHERE organization_id=?)) OR (sl.related_order_type='outbound' AND sl.related_order_id NOT IN (SELECT id FROM outbound_orders WHERE organization_id=?)))`, org, org, org).Scan(&count); err != nil {
			t.Fatal(err)
		}
		return count
	}
	aBalanceSteps := []struct{ label, want string }{
		{"初始", "10.000000"},
		{"A 入库 5 后", "15.000000"},
		{"A 出库 3 后", "12.000000"},
		{"A 编辑入库 5→8 后", "15.000000"},
		{"A 删除入库单后", "7.000000"},
	}
	if got := balance(201, 201); got != aBalanceSteps[0].want {
		t.Fatalf("初始 A 余额=%s, want %s", got, aBalanceSteps[0].want)
	}
	if got := balance(202, 202); got != "50.000000" {
		t.Fatalf("初始 B 余额=%s, want 50.000000", got)
	}

	// 1) A 入库 5。
	w := request("POST", "/api/inbound", `{"handler":"h","supplier":"s","items":[{"material_id":201,"quantity":5}]}`, 201)
	expectStatus(w, 201)
	var inbound struct {
		Data struct {
			ID int64 `json:"id"`
		} `json:"data"`
	}
	if err := json.Unmarshal(w.Body.Bytes(), &inbound); err != nil || inbound.Data.ID == 0 {
		t.Fatalf("解析入库单失败: %v body=%s", err, w.Body.String())
	}
	if got := balance(201, 201); got != aBalanceSteps[1].want {
		t.Fatalf("A 入库后余额=%s, want %s", got, aBalanceSteps[1].want)
	}

	// 2) A 出库 3。
	expectStatus(request("POST", "/api/outbound", `{"receiver":"r","items":[{"material_id":201,"quantity":3}]}`, 201), 201)
	if got := balance(201, 201); got != aBalanceSteps[2].want {
		t.Fatalf("A 出库后余额=%s, want %s", got, aBalanceSteps[2].want)
	}

	// 3) A 编辑入库单 5→8。
	expectStatus(request("PUT", fmt.Sprintf("/api/inbound/%d", inbound.Data.ID), `{"handler":"h","supplier":"s","items":[{"material_id":201,"quantity":8}]}`, 201), 200)
	if got := balance(201, 201); got != aBalanceSteps[3].want {
		t.Fatalf("A 编辑后余额=%s, want %s", got, aBalanceSteps[3].want)
	}

	// 4) A 删除入库单。
	expectStatus(request("DELETE", fmt.Sprintf("/api/inbound/%d", inbound.Data.ID), "", 201), 200)
	if got := balance(201, 201); got != aBalanceSteps[4].want {
		t.Fatalf("A 删除后余额=%s, want %s", got, aBalanceSteps[4].want)
	}

	// 至此 A 的库存与单据变化只落在 A 上，B 一直是 50、无单据无流水。
	if got := balance(202, 202); got != "50.000000" {
		t.Fatalf("A 操作后 B 余额=%s, want 50.000000", got)
	}
	if orderCount("inbound_orders", 202) != 0 || orderCount("outbound_orders", 202) != 0 {
		t.Fatalf("A 操作影响了 B 的单据")
	}
	if got := orderCount("outbound_orders", 201); got != 1 {
		t.Fatalf("A 出库单数=%d, want 1", got)
	}

	// 5) 库存不足：A 出库 100 失败，余额不变，不留半张出库单或孤立流水。
	logsBefore := countLogs(t, db, 201)
	expectStatus(request("POST", "/api/outbound", `{"receiver":"r","items":[{"material_id":201,"quantity":100}]}`, 201), 400)
	if got := balance(201, 201); got != aBalanceSteps[4].want {
		t.Fatalf("库存不足后 A 余额=%s, want %s", got, aBalanceSteps[4].want)
	}
	if got := orderCount("outbound_orders", 201); got != 1 {
		t.Fatalf("库存不足留下了半张出库单: %d 张", got)
	}
	if countLogs(t, db, 201) != logsBefore || orphanLogs(201) != 0 {
		t.Fatalf("库存不足留下了孤立流水")
	}

	// 6) 仓库停用：改变库存的入库请求回 409，不落任何单据。
	exec(`UPDATE warehouses SET status='inactive' WHERE organization_id=201`)
	logsBefore = countLogs(t, db, 201)
	expectStatus(request("POST", "/api/inbound", `{"handler":"h","supplier":"s","items":[{"material_id":201,"quantity":1}]}`, 201), 409)
	if got := orderCount("inbound_orders", 201); got != 0 {
		t.Fatalf("仓库停用留下了半张入库单: %d 张", got)
	}
	if countLogs(t, db, 201) != logsBefore || orphanLogs(201) != 0 {
		t.Fatalf("仓库停用留下了孤立流水")
	}
	if got := balance(201, 201); got != aBalanceSteps[4].want {
		t.Fatalf("仓库停用后 A 余额=%s, want %s", got, aBalanceSteps[4].want)
	}
	if got := balance(202, 202); got != "50.000000" {
		t.Fatalf("失败操作影响了 B 余额: %s", got)
	}
}

func countLogs(t *testing.T, db *sql.DB, organizationID int64) int {
	t.Helper()
	var count int
	if err := db.QueryRow(`SELECT COUNT(*) FROM stock_logs WHERE organization_id=?`, organizationID).Scan(&count); err != nil {
		t.Fatal(err)
	}
	return count
}