package dbs

import (
	"encoding/json"
	"fmt"
	"strings"
	"time"

	"git.x2erp.com/qdy/go-svc-mcp/internal/mcp"
)

func init() {
	mcp.Register("get_oracle_create_table", "在Oracle数据库中创建新表，支持字段约束和注释",
		map[string]interface{}{
			"type": "object",
			"properties": map[string]interface{}{
				"table_name": map[string]interface{}{
					"type":        "string",
					"description": "表名称",
				},
				"table_description": map[string]interface{}{
					"type":        "string",
					"description": "表描述/注释",
					"default":     "",
				},
				"schema": map[string]interface{}{
					"type":        "string",
					"description": "模式名称（默认为当前用户）",
					"default":     "",
				},
				"database_key": map[string]interface{}{
					"type":        "string",
					"description": "数据库配置键名（如：business），可选，默认使用主数据库",
					"enum":        []string{"warehouse", "business"},
					"default":     "warehouse",
				},

				"fields": map[string]interface{}{
					"type":        "array",
					"description": "字段定义",
					"items": map[string]interface{}{
						"type": "object",
						"properties": map[string]interface{}{
							"field_name": map[string]interface{}{
								"type":        "string",
								"description": "字段名称",
							},
							"data_type": map[string]interface{}{
								"type":        "string",
								"description": "数据类型（如 VARCHAR2(255), NUMBER, DATE 等）",
							},
							"is_nullable": map[string]interface{}{
								"type":        "boolean",
								"description": "是否允许为空",
								"default":     true,
							},
							"field_default": map[string]interface{}{
								"type":        "string",
								"description": "默认值",
								"default":     "",
							},
							"field_description": map[string]interface{}{
								"type":        "string",
								"description": "字段描述/注释",
								"default":     "",
							},
							"is_primary_key": map[string]interface{}{
								"type":        "boolean",
								"description": "是否为主键",
								"default":     false,
							},
							"is_unique": map[string]interface{}{
								"type":        "boolean",
								"description": "是否唯一约束",
								"default":     false,
							},
							"auto_increment": map[string]interface{}{
								"type":        "boolean",
								"description": "是否自增（使用GENERATED ALWAYS AS IDENTITY）",
								"default":     false,
							},
						},
						"required": []string{"field_name", "data_type"},
					},
				},
			},
			"required": []string{"table_name", "fields"},
		},
		func(input json.RawMessage, deps *mcp.ToolDependencies) (interface{}, error) {
			var params struct {
				TableName        string `json:"table_name"`
				TableDescription string `json:"table_description"`
				Schema           string `json:"schema"`
				DatabaseKey      string `json:"database_key"`
				Fields           []struct {
					FieldName        string `json:"field_name"`
					DataType         string `json:"data_type"`
					IsNullable       bool   `json:"is_nullable"`
					FieldDefault     string `json:"field_default"`
					FieldDescription string `json:"field_description"`
					IsPrimaryKey     bool   `json:"is_primary_key"`
					IsUnique         bool   `json:"is_unique"`
					AutoIncrement    bool   `json:"auto_increment"`
				} `json:"fields"`
			}

			if len(input) > 0 {
				if err := json.Unmarshal(input, &params); err != nil {
					return nil, err
				}
			}

			// 获取数据库工厂
			dbFactory, err := GetDBFactory(params.DatabaseKey, deps)
			if err != nil {
				return nil, err
			}

			// 获取数据库类型，确保是Oracle
			dbType := dbFactory.GetDBType()
			if dbType != "oracle" {
				return nil, fmt.Errorf("当前数据库类型为 %s，此工具仅支持Oracle数据库", dbType)
			}

			// 获取当前用户名（Oracle中的schema）
			currentUser := dbFactory.GetDatabaseName()
			schema := strings.TrimSpace(params.Schema)
			if schema == "" {
				schema = currentUser
			}

			tableName := strings.TrimSpace(params.TableName)
			if tableName == "" {
				return nil, fmt.Errorf("表名称不能为空")
			}

			if len(params.Fields) == 0 {
				return nil, fmt.Errorf("至少需要定义一个字段")
			}

			// 检查表是否已存在
			var tableExistsQuery string
			var tableCheckResults []map[string]interface{}

			if strings.ToUpper(schema) == strings.ToUpper(currentUser) {
				// 检查当前用户下的表
				tableExistsQuery = `SELECT COUNT(*) as table_count FROM user_tables WHERE table_name = UPPER(:1)`
				tableCheckResults, err = dbFactory.QuerySliceMapWithParams(tableExistsQuery, tableName)
			} else {
				// 检查指定模式下的表
				tableExistsQuery = `SELECT COUNT(*) as table_count FROM all_tables WHERE owner = UPPER(:1) AND table_name = UPPER(:2)`
				tableCheckResults, err = dbFactory.QuerySliceMapWithParams(tableExistsQuery, schema, tableName)
			}

			if err != nil {
				return nil, fmt.Errorf("检查表是否存在失败: %v", err)
			}

			tableExists := false
			if len(tableCheckResults) > 0 {
				if count, ok := tableCheckResults[0]["table_count"].(int64); ok && count > 0 {
					tableExists = true
				}
			}

			if tableExists {
				return nil, fmt.Errorf("表 '%s' 已存在于模式 '%s' 中", tableName, schema)
			}

			// 构建建表SQL
			var fieldDefinitions []string
			var primaryKeyFields []string

			for _, field := range params.Fields {
				fieldName := strings.TrimSpace(field.FieldName)
				dataType := strings.TrimSpace(field.DataType)
				if fieldName == "" || dataType == "" {
					return nil, fmt.Errorf("字段名称和数据类型不能为空")
				}

				// 构建字段定义
				fieldDef := fmt.Sprintf(`"%s" %s`, fieldName, dataType)

				// 添加NOT NULL约束
				if !field.IsNullable {
					fieldDef += " NOT NULL"
				}

				// 添加默认值
				if field.FieldDefault != "" {
					fieldDef += fmt.Sprintf(" DEFAULT %s", field.FieldDefault)
				}

				// 添加自增（Oracle 12c+ 使用IDENTITY列）
				if field.AutoIncrement {
					fieldDef += " GENERATED ALWAYS AS IDENTITY"
				}

				// 添加唯一约束（如果不是主键）
				if field.IsUnique && !field.IsPrimaryKey {
					fieldDef += " UNIQUE"
				}

				fieldDefinitions = append(fieldDefinitions, fieldDef)

				// 收集主键字段
				if field.IsPrimaryKey {
					primaryKeyFields = append(primaryKeyFields, fmt.Sprintf(`"%s"`, fieldName))
				}
			}

			// 构建完整的CREATE TABLE语句
			createTableSQL := fmt.Sprintf(`CREATE TABLE "%s"."%s" (%s)`, schema, tableName, strings.Join(fieldDefinitions, ", "))

			// 添加主键约束
			if len(primaryKeyFields) > 0 {
				createTableSQL += fmt.Sprintf(` CONSTRAINT "%s_PK" PRIMARY KEY (%s)`, tableName, strings.Join(primaryKeyFields, ", "))
			}

			// 执行建表SQL
			_, err = dbFactory.Execute(createTableSQL)
			if err != nil {
				return nil, fmt.Errorf("创建表失败: %v", err)
			}

			// 添加表注释
			tableDescription := strings.TrimSpace(params.TableDescription)
			if tableDescription != "" {
				commentSQL := fmt.Sprintf(`COMMENT ON TABLE "%s"."%s" IS '%s'`, schema, tableName, strings.ReplaceAll(tableDescription, "'", "''"))
				_, err = dbFactory.Execute(commentSQL)
				if err != nil {
					fmt.Printf("添加表注释失败: %v\n", err)
				}
			}

			// 添加字段注释
			for _, field := range params.Fields {
				fieldDescription := strings.TrimSpace(field.FieldDescription)
				if fieldDescription != "" {
					fieldName := strings.TrimSpace(field.FieldName)
					commentSQL := fmt.Sprintf(`COMMENT ON COLUMN "%s"."%s"."%s" IS '%s'`, schema, tableName, fieldName, strings.ReplaceAll(fieldDescription, "'", "''"))
					_, err = dbFactory.Execute(commentSQL)
					if err != nil {
						fmt.Printf("添加字段注释失败: %v\n", err)
					}
				}
			}

			return map[string]interface{}{
				"tenant_id":          deps.ReqCtx.TenantID,
				"user_id":            deps.ReqCtx.UserID,
				"database_type":      dbType,
				"database_name":      dbFactory.GetDatabaseName(),
				"schema":             schema,
				"table_name":         tableName,
				"table_description":  tableDescription,
				"total_fields":       len(params.Fields),
				"primary_key_fields": len(primaryKeyFields),
				"sql_statement":      createTableSQL,
				"status":             "success",
				"message":            fmt.Sprintf("表 '%s' 创建成功", tableName),
				"timestamp":          time.Now().Format(time.RFC3339),
			}, nil
		},
	)
}