//
//  Copyright 2026 The InfiniFlow Authors. All Rights Reserved.
//
//  Licensed under the Apache License, Version 2.0 (the "License");
//  you may not use this file except in compliance with the License.
//  You may obtain a copy of the License at
//
//      http://www.apache.org/licenses/LICENSE-2.0
//
//  Unless required by applicable law or agreed to in writing, software
//  distributed under the License is distributed on an "AS IS" BASIS,
//  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
//  See the License for the specific language governing permissions and
//  limitations under the License.
//

package infinity

import (
	"context"
	"encoding/json"
	"fmt"
	"os"
	"path/filepath"
	"regexp"
	"strconv"
	"strings"

	infinity "github.com/infiniflow/infinity-go-sdk"
	"ragflow/internal/logger"
	"ragflow/internal/utility"

	"go.uber.org/zap"
)

// CreateDataset creates a table in Infinity
// indexName is the table name prefix (e.g., "ragflow_<tenant_id>")
// The full table name is built as "{indexName}_{datasetID}"
func (e *infinityEngine) CreateDataset(ctx context.Context, indexName, datasetID string, vectorSize int, parserID string) error {
	vecSize := vectorSize

	// Build full table name: {indexName}_{datasetID}
	tableName := fmt.Sprintf("%s_%s", indexName, datasetID)

	// Use configured schema
	fpMapping := filepath.Join(utility.GetProjectRoot(), "conf", e.mappingFileName)

	schemaData, err := os.ReadFile(fpMapping)
	if err != nil {
		return fmt.Errorf("Failed to read mapping file: %w", err)
	}

	var schema orderedFields
	if err := json.Unmarshal(schemaData, &schema); err != nil {
		return fmt.Errorf("Failed to parse mapping file: %w", err)
	}

	// Get database
	db, err := e.client.conn.GetDatabase(e.client.dbName)
	if err != nil {
		return fmt.Errorf("Failed to get database: %w", err)
	}

	// Check if table already exists
	exists, err := e.TableExists(ctx, tableName)
	if err != nil {
		return fmt.Errorf("Failed to check if table exists: %w", err)
	}
	if exists {
		return fmt.Errorf("table '%s' already exists", tableName)
	}

	// Build column definitions (preserving JSON order)
	var columns infinity.TableSchema
	for _, fieldName := range schema.Keys {
		fieldInfo := schema.Fields[fieldName]
		col := infinity.ColumnDefinition{
			Name:     fieldName,
			DataType: fieldInfo.Type,
			Default:  fieldInfo.Default,
			// Comment:  fieldInfo.Comment,
		}
		columns = append(columns, &col)
	}

	// Add vector column
	vectorColName := fmt.Sprintf("q_%d_vec", vecSize)
	columns = append(columns, &infinity.ColumnDefinition{
		Name:     vectorColName,
		DataType: fmt.Sprintf("vector,%d,float", vecSize),
	})

	// Add chunk_data column for table parser
	if parserID == "table" {
		columns = append(columns, &infinity.ColumnDefinition{
			Name:     "chunk_data",
			DataType: "json",
			Default:  "{}",
		})
	}

	// Create table
	table, err := db.CreateTable(tableName, columns, infinity.ConflictTypeIgnore)
	if err != nil {
		return fmt.Errorf("Failed to create table: %w", err)
	}
	logger.Debug("Infinity created table", zap.String("tableName", tableName))

	// Create HNSW index on vector column
	_, err = table.CreateIndex(
		"q_vec_idx",
		infinity.NewIndexInfo(vectorColName, infinity.IndexTypeHnsw, map[string]string{
			"M":               "16",
			"ef_construction": "50",
			"metric":          "cosine",
			"encode":          "lvq",
		}),
		infinity.ConflictTypeIgnore,
		"",
	)
	if err != nil {
		return fmt.Errorf("Failed to create HNSW index: %w", err)
	}

	// Create full-text indexes for varchar fields with analyzers
	for _, fieldName := range schema.Keys {
		fieldInfo := schema.Fields[fieldName]
		if fieldInfo.Type != "varchar" || fieldInfo.Analyzer == nil {
			continue
		}

		analyzers := []string{}
		switch a := fieldInfo.Analyzer.(type) {
		case string:
			analyzers = []string{a}
		case []interface{}:
			for _, v := range a {
				if s, ok := v.(string); ok {
					analyzers = append(analyzers, s)
				}
			}
		}

		for _, analyzer := range analyzers {
			indexNameFt := fmt.Sprintf("ft_%s_%s",
				regexp.MustCompile(`[^a-zA-Z0-9]`).ReplaceAllString(fieldName, "_"),
				regexp.MustCompile(`[^a-zA-Z0-9]`).ReplaceAllString(analyzer, "_"),
			)
			_, err = table.CreateIndex(
				indexNameFt,
				infinity.NewIndexInfo(fieldName, infinity.IndexTypeFullText, map[string]string{"ANALYZER": analyzer}),
				infinity.ConflictTypeIgnore,
				"",
			)
			if err != nil {
				return fmt.Errorf("Failed to create fulltext index %s: %w", indexNameFt, err)
			}
		}
	}

	// Create secondary indexes for fields with index_type
	for _, fieldName := range schema.Keys {
		fieldInfo := schema.Fields[fieldName]
		if fieldInfo.IndexType == nil {
			continue
		}

		indexTypeStr := ""
		params := map[string]string{}

		switch it := fieldInfo.IndexType.(type) {
		case string:
			indexTypeStr = it
		case map[string]interface{}:
			if t, ok := it["type"].(string); ok {
				indexTypeStr = t
			}
			if card, ok := it["cardinality"].(string); ok {
				params["cardinality"] = card
			}
		}

		if indexTypeStr == "secondary" {
			indexNameSec := fmt.Sprintf("sec_%s", fieldName)
			_, err = table.CreateIndex(
				indexNameSec,
				infinity.NewIndexInfo(fieldName, infinity.IndexTypeSecondary, params),
				infinity.ConflictTypeIgnore,
				"",
			)
			if err != nil {
				return fmt.Errorf("Failed to create secondary index %s: %w", indexNameSec, err)
			}
		}
	}

	_ = table // suppress unused variable warning
	return nil
}

// InsertDataset inserts chunks into a dataset table
// Table name format: {tableNamePrefix}_{knowledgebaseID}
// Auto-create the table if it doesn't exist
// Delete existing rows with matching IDs before insert
func (e *infinityEngine) InsertDataset(ctx context.Context, chunks []map[string]interface{}, tableNamePrefix string, knowledgebaseID string) ([]string, error) {
	tableName := fmt.Sprintf("%s_%s", tableNamePrefix, knowledgebaseID)
	logger.Info("InfinityConnection.InsertDataset called", zap.String("tableName", tableName), zap.Int("chunkCount", len(chunks)))

	db, err := e.client.conn.GetDatabase(e.client.dbName)
	if err != nil {
		return nil, fmt.Errorf("Failed to get database: %w", err)
	}

	table, err := db.GetTable(tableName)
	if err != nil {
		// Table doesn't exist, try to create it
		errMsg := strings.ToLower(err.Error())
		if !strings.Contains(errMsg, "not found") && !strings.Contains(errMsg, "doesn't exist") {
			return nil, fmt.Errorf("Failed to get table %s: %w", tableName, err)
		}

		// Infer vector size from chunks
		vectorSize := 0
		vectorPattern := regexp.MustCompile(`q_(\d+)_vec`)
		for _, chunk := range chunks {
			for key := range chunk {
				matches := vectorPattern.FindStringSubmatch(key)
				if len(matches) >= 2 {
					vectorSize, _ = strconv.Atoi(matches[1])
					break
				}
			}
			if vectorSize > 0 {
				break
			}
		}
		if vectorSize == 0 {
			return nil, fmt.Errorf("cannot infer vector size from chunks")
		}

		// Determine parser_id from chunk structure
		parserID := ""
		if chunkData, ok := chunks[0]["chunk_data"].(map[string]interface{}); ok && chunkData != nil {
			parserID = "table"
		}

		// Create table
		if err := e.CreateDataset(ctx, tableNamePrefix, knowledgebaseID, vectorSize, parserID); err != nil {
			return nil, fmt.Errorf("Failed to create table: %w", err)
		}

		table, err = db.GetTable(tableName)
		if err != nil {
			return nil, fmt.Errorf("Failed to get table after creation: %w", err)
		}
	}

	// Get embedding columns and their sizes
	var embeddingCols [][2]interface{}
	colsResp, err := table.ShowColumns()
	if err != nil {
		return nil, fmt.Errorf("Failed to get columns: %w", err)
	}
	result, ok := colsResp.(*infinity.QueryResult)
	if !ok {
		return nil, fmt.Errorf("unexpected response type: %T", colsResp)
	}

	// ShowColumns returns a result set where Data contains arrays of column values
	re := regexp.MustCompile(`Embedding\([a-z]+,(\d+)\)`)
	if nameArr, ok := result.Data["name"]; ok {
		if typeArr, ok := result.Data["type"]; ok {
			for i := 0; i < len(nameArr); i++ {
				colName, _ := nameArr[i].(string)
				colType, _ := typeArr[i].(string)
				matches := re.FindStringSubmatch(colType)
				if len(matches) >= 2 {
					size, _ := strconv.Atoi(matches[1])
					embeddingCols = append(embeddingCols, [2]interface{}{colName, size})
				}
			}
		}
	}

	// Transform chunks using helper function
	insertChunks := make([]map[string]interface{}, len(chunks))
	for i, chunk := range chunks {
		insertChunks[i] = TransformChunkFields(chunk, embeddingCols)
	}

	// Delete existing rows with matching IDs
	if len(insertChunks) > 0 {
		idList := make([]string, len(insertChunks))
		for i, chunk := range insertChunks {
			idList[i] = fmt.Sprintf("'%v'", chunk["id"])
		}
		filter := fmt.Sprintf("id IN (%s)", strings.Join(idList, ", "))
		logger.Debug(fmt.Sprintf("Deleting existing rows with filter: %s", filter))
		delResp, delErr := table.Delete(filter)
		if delErr != nil {
			logger.Warn(fmt.Sprintf("Failed to delete existing rows: %v", delErr))
		} else {
			logger.Info(fmt.Sprintf("Deleted %d existing rows", delResp.DeletedRows))
		}
	}

	// Insert chunks to dataset
	_, err = table.Insert(insertChunks)
	if err != nil {
		return nil, fmt.Errorf("Failed to insert chunks to dataset: %w", err)
	}

	logger.Info("InfinityConnection.InsertDataset result", zap.String("tableName", tableName), zap.Int("count", len(insertChunks)))
	return []string{}, nil
}

// UpdateDataset updates chunks in a dataset table
// Table name format: {tableNamePrefix}_{knowledgebaseID}
func (e *infinityEngine) UpdateDataset(ctx context.Context, condition map[string]interface{}, newValue map[string]interface{}, tableNamePrefix string, knowledgebaseID string) error {
	tableName := fmt.Sprintf("%s_%s", tableNamePrefix, knowledgebaseID)
	logger.Info("InfinityConnection.UpdateDataset called", zap.String("tableName", tableName), zap.Any("condition", condition))

	db, err := e.client.conn.GetDatabase(e.client.dbName)
	if err != nil {
		return fmt.Errorf("Failed to get database: %w", err)
	}

	table, err := db.GetTable(tableName)
	if err != nil {
		return fmt.Errorf("Failed to get table %s: %w", tableName, err)
	}

	// Get table columns
	clmns := make(map[string]struct {
		Type    string
		Default interface{}
	})
	colsResp, err := table.ShowColumns()
	if err != nil {
		return fmt.Errorf("Failed to get columns: %w", err)
	}
	result, ok := colsResp.(*infinity.QueryResult)
	if ok {
		if nameArr, ok := result.Data["name"]; ok {
			if typeArr, ok := result.Data["type"]; ok {
				if defArr, ok := result.Data["default"]; ok {
					for i := 0; i < len(nameArr); i++ {
						colName, _ := nameArr[i].(string)
						colType, _ := typeArr[i].(string)
						var colDefault interface{}
						if i < len(defArr) {
							colDefault = defArr[i]
						}
						clmns[colName] = struct {
							Type    string
							Default interface{}
						}{colType, colDefault}
					}
				}
			}
		}
	}

	// Build filter string from condition
	filter := buildFilterFromCondition(condition, clmns)

	// Process remove operation first
	removeValue := make(map[string]interface{})
	if removeData, ok := newValue["remove"].(map[string]interface{}); ok {
		removeValue = removeData
	}
	delete(newValue, "remove")

	// Transform new_value fields using helper function (no embeddings needed for update)
	transformed := TransformChunkFields(newValue, nil)
	for k, v := range transformed {
		newValue[k] = v
	}

	// Remove original fields that were transformed (they're now in transformed with new names/types)
	// Also remove intermediate token fields that shouldn't be stored in Infinity
	// This must match Python's delete list in infinity_conn.py
	for _, key := range []string{"docnm_kwd", "title_tks", "title_sm_tks", "important_kwd", "important_tks",
		"content_with_weight", "content_ltks", "content_sm_ltks", "authors_tks", "authors_sm_tks",
		"question_kwd", "question_tks"} {
		delete(newValue, key)
	}

	// Handle remove operations if any
	if len(removeValue) > 0 {
		colToRemove := make([]string, 0, len(removeValue))
		for k := range removeValue {
			colToRemove = append(colToRemove, k)
		}
		colToRemove = append(colToRemove, "id")

		// Query rows to be updated
		queryResult, err := table.Output(colToRemove).Filter(filter).ToResult()
		if err != nil {
			logger.Warn(fmt.Sprintf("Failed to query rows for remove operation: %v", err))
		} else {
			qr, ok := queryResult.(*infinity.QueryResult)
			if ok && len(qr.Data) > 0 {
				// Get the id column and columns to remove
				idCol := qr.Data["id"]
				removeOpt := make(map[string]map[string][]string) // column -> value -> [ids]

				for colName, colData := range qr.Data {
					if colName == "id" {
						continue
					}
					removeVal := removeValue[colName]
					for i, id := range idCol {
						if i < len(colData) {
							existingVal := colData[i]
							if removeStr, ok := removeVal.(string); ok {
								// Split existing value by ### and remove the target value
								if existingStr, ok := existingVal.(string); ok {
									parts := strings.Split(existingStr, "###")
									var newParts []string
									for _, p := range parts {
										if p != removeStr {
											newParts = append(newParts, p)
										}
									}
									if len(newParts) != len(parts) {
										idStr := fmt.Sprintf("%v", id)
										if removeOpt[colName] == nil {
											removeOpt[colName] = make(map[string][]string)
										}
										removeOpt[colName][strings.Join(newParts, "###")] = append(removeOpt[colName][strings.Join(newParts, "###")], idStr)
									}
								}
							}
						}
					}
				}

				// Execute remove updates
				for colName, valueToIDs := range removeOpt {
					for newVal, ids := range valueToIDs {
						idFilter := filter + " AND id IN (" + strings.Join(ids, ", ") + ")"
						logger.Info(fmt.Sprintf("INFINITY remove update: table=%s, idFilter=%s, column=%s, newValue=%v", tableName, idFilter, colName, newVal))
						_, err := table.Update(idFilter, map[string]interface{}{colName: newVal})
						if err != nil {
							logger.Warn(fmt.Sprintf("Failed to remove value from column %s: %v", colName, err))
						}
					}
				}
			}
		}
	}

	// Execute the main update
	logger.Info(fmt.Sprintf("INFINITY update: table=%s, filter=%s, newValue=%v", tableName, filter, newValue))
	_, err = table.Update(filter, newValue)
	if err != nil {
		return fmt.Errorf("Failed to update chunks: %w", err)
	}

	logger.Info("InfinityConnection.UpdateDataset completes", zap.String("tableName", tableName))
	return nil
}

// TransformChunkFields transforms chunk field name for insert/update
// It handles field name conversions and value transformations:
// - docnm_kwd -> docnm
// - title_kwd/title_sm_tks -> docnm (if docnm_kwd not set)
// - important_kwd -> important_keywords (+ important_kwd_empty_count)
// - content_with_weight/content_ltks/content_sm_ltks -> content
// - authors_tks/authors_sm_tks -> authors
// - question_kwd -> questions (joined with \n), question_tks -> questions (if question_kwd not set)
// - kb_id: list -> str (first element)
// - position_int: list -> hex_joined string
// - page_num_int, top_int: list -> hex string
// - *_feas fields -> JSON string
// - keyword fields with list values -> ### joined string
// - chunk_data: dict -> JSON string
// - Missing embeddings filled with zeros if embeddingCols provided
func TransformChunkFields(chunk map[string]interface{}, embeddingCols [][2]interface{}) map[string]interface{} {
	d := make(map[string]interface{})

	for k, v := range chunk {
		switch k {
		case "docnm_kwd":
			d["docnm"] = v
		case "title_kwd":
			if _, exists := chunk["docnm_kwd"]; !exists {
				d["docnm"] = utility.ConvertToString(v)
			}
		case "title_sm_tks":
			if _, exists := chunk["docnm_kwd"]; !exists {
				d["docnm"] = utility.ConvertToString(v)
			}
		case "important_kwd":
			if list, ok := v.([]interface{}); ok {
				emptyCount := 0
				tokens := make([]string, 0)
				for _, item := range list {
					if str, ok := item.(string); ok {
						if str == "" {
							emptyCount++
						} else {
							tokens = append(tokens, str)
						}
					}
				}
				d["important_keywords"] = strings.Join(tokens, ",")
				d["important_kwd_empty_count"] = emptyCount
			} else {
				d["important_keywords"] = utility.ConvertToString(v)
			}
		case "important_tks":
			if _, exists := chunk["important_kwd"]; !exists {
				d["important_keywords"] = v
			}
		case "content_with_weight":
			d["content"] = v
		case "content_ltks":
			if _, exists := chunk["content_with_weight"]; !exists {
				d["content"] = v
			}
		case "content_sm_ltks":
			if _, exists := chunk["content_with_weight"]; !exists {
				d["content"] = v
			}
		case "authors_tks":
			d["authors"] = v
		case "authors_sm_tks":
			if _, exists := chunk["authors_tks"]; !exists {
				d["authors"] = v
			}
		case "question_kwd":
			d["questions"] = strings.Join(utility.ConvertToStringSlice(v), "\n")
		case "tag_kwd":
			d["tag_kwd"] = strings.Join(utility.ConvertToStringSlice(v), "###")
		case "question_tks":
			if _, exists := chunk["question_kwd"]; !exists {
				d["questions"] = utility.ConvertToString(v)
			}
		case "kb_id":
			if list, ok := v.([]interface{}); ok && len(list) > 0 {
				d["kb_id"] = list[0]
			} else {
				d["kb_id"] = v
			}
		case "position_int":
			if list, ok := v.([]interface{}); ok {
				d["position_int"] = utility.ConvertPositionIntArrayToHex(list)
			} else {
				d["position_int"] = v
			}
		case "page_num_int", "top_int":
			if list, ok := v.([]interface{}); ok {
				d[k] = utility.ConvertIntArrayToHex(list)
			} else {
				d[k] = v
			}
		case "chunk_data":
			d["chunk_data"] = utility.ConvertMapToJSONString(v)
		default:
			// Check for *_feas fields
			if strings.HasSuffix(k, "_feas") {
				jsonBytes, _ := json.Marshal(v)
				d[k] = string(jsonBytes)
			} else if fieldKeyword(k) {
				// keyword fields with list values -> ### joined
				if list, ok := v.([]interface{}); ok {
					d[k] = strings.Join(utility.ConvertToStringSlice(list), "###")
				} else {
					d[k] = v
				}
			} else {
				d[k] = v
			}
		}
	}

	// Remove intermediate token fields
	for _, key := range []string{"docnm_kwd", "title_tks", "title_sm_tks", "important_kwd", "important_tks",
		"content_with_weight", "content_ltks", "content_sm_ltks", "authors_tks", "authors_sm_tks",
		"question_kwd", "question_tks"} {
		delete(d, key)
	}

	// Fill missing embedding columns with zeros if embedding info provided
	for _, ec := range embeddingCols {
		name, ok1 := ec[0].(string)
		size, ok2 := ec[1].(int)
		if !ok1 || !ok2 {
			continue
		}
		if _, exists := d[name]; !exists {
			zeros := make([]float64, size)
			for i := range zeros {
				zeros[i] = 0
			}
			d[name] = zeros
		}
	}

	return d
}