package ui

import (
	"errors"
	"fmt"
	"strings"

	"git.warky.dev/wdevs/relspecgo/pkg/models"
)

// Data operations for indexes, views, sequences, scripts and domain/table assignment.

func (se *SchemaEditor) schemaAt(schemaIndex int) (*models.Schema, error) {
	if schemaIndex < 0 || schemaIndex >= len(se.db.Schemas) {
		return nil, errors.New("schema not found")
	}
	return se.db.Schemas[schemaIndex], nil
}

func (se *SchemaEditor) tableAt(schemaIndex, tableIndex int) (*models.Schema, *models.Table, error) {
	schema, err := se.schemaAt(schemaIndex)
	if err != nil {
		return nil, nil, err
	}
	if tableIndex < 0 || tableIndex >= len(schema.Tables) {
		return nil, nil, errors.New("table not found")
	}
	return schema, schema.Tables[tableIndex], nil
}

// splitList splits a comma separated list, trimming blanks and dropping empty entries.
func splitList(s string) []string {
	parts := make([]string, 0)
	for _, p := range strings.Split(s, ",") {
		if p = strings.TrimSpace(p); p != "" {
			parts = append(parts, p)
		}
	}
	return parts
}

// SaveIndex adds an index to a table. When oldName is non-empty the index of that
// name is replaced (and renamed if needed).
func (se *SchemaEditor) SaveIndex(schemaIndex, tableIndex int, oldName string, idx *models.Index) error {
	schema, table, err := se.tableAt(schemaIndex, tableIndex)
	if err != nil {
		return err
	}
	idx.Name = strings.TrimSpace(idx.Name)
	if idx.Name == "" {
		return errors.New("index name is required")
	}
	if len(idx.Columns) == 0 {
		return errors.New("index needs at least one column")
	}
	for _, c := range idx.Columns {
		if _, ok := table.Columns[c]; !ok {
			return fmt.Errorf("column %q not found in table %s", c, table.Name)
		}
	}
	if _, exists := table.Indexes[idx.Name]; exists && idx.Name != oldName {
		return fmt.Errorf("index %q already exists", idx.Name)
	}
	if table.Indexes == nil {
		table.Indexes = make(map[string]*models.Index)
	}
	if oldName != "" {
		delete(table.Indexes, oldName)
	}
	idx.Table = table.Name
	idx.Schema = schema.Name
	table.Indexes[idx.Name] = idx
	table.UpdateDate()
	se.db.UpdateDate()
	return nil
}

// DeleteIndex removes an index from a table.
func (se *SchemaEditor) DeleteIndex(schemaIndex, tableIndex int, name string) bool {
	_, table, err := se.tableAt(schemaIndex, tableIndex)
	if err != nil {
		return false
	}
	if _, ok := table.Indexes[name]; !ok {
		return false
	}
	delete(table.Indexes, name)
	table.UpdateDate()
	se.db.UpdateDate()
	return true
}

// SaveView adds a view to a schema, or replaces the one at position at (use -1 to add).
func (se *SchemaEditor) SaveView(schemaIndex, at int, v *models.View) error {
	schema, err := se.schemaAt(schemaIndex)
	if err != nil {
		return err
	}
	v.Name = strings.TrimSpace(v.Name)
	if v.Name == "" {
		return errors.New("view name is required")
	}
	if strings.TrimSpace(v.Definition) == "" {
		return errors.New("view definition is required")
	}
	for i, o := range schema.Views {
		if i != at && o.Name == v.Name {
			return fmt.Errorf("view %q already exists", v.Name)
		}
	}
	v.Schema = schema.Name
	if at >= 0 && at < len(schema.Views) {
		schema.Views[at] = v
	} else {
		schema.Views = append(schema.Views, v)
	}
	schema.UpdateDate()
	se.db.UpdateDate()
	return nil
}

// DeleteView removes the view at position at.
func (se *SchemaEditor) DeleteView(schemaIndex, at int) bool {
	schema, err := se.schemaAt(schemaIndex)
	if err != nil || at < 0 || at >= len(schema.Views) {
		return false
	}
	schema.Views = append(schema.Views[:at], schema.Views[at+1:]...)
	schema.UpdateDate()
	se.db.UpdateDate()
	return true
}

// SaveSequence adds a sequence to a schema, or replaces the one at position at (use -1 to add).
func (se *SchemaEditor) SaveSequence(schemaIndex, at int, s *models.Sequence) error {
	schema, err := se.schemaAt(schemaIndex)
	if err != nil {
		return err
	}
	s.Name = strings.TrimSpace(s.Name)
	if s.Name == "" {
		return errors.New("sequence name is required")
	}
	if s.IncrementBy == 0 {
		return errors.New("increment must not be zero")
	}
	for i, o := range schema.Sequences {
		if i != at && o.Name == s.Name {
			return fmt.Errorf("sequence %q already exists", s.Name)
		}
	}
	s.Schema = schema.Name
	if at >= 0 && at < len(schema.Sequences) {
		schema.Sequences[at] = s
	} else {
		schema.Sequences = append(schema.Sequences, s)
	}
	schema.UpdateDate()
	se.db.UpdateDate()
	return nil
}

// DeleteSequence removes the sequence at position at.
func (se *SchemaEditor) DeleteSequence(schemaIndex, at int) bool {
	schema, err := se.schemaAt(schemaIndex)
	if err != nil || at < 0 || at >= len(schema.Sequences) {
		return false
	}
	schema.Sequences = append(schema.Sequences[:at], schema.Sequences[at+1:]...)
	schema.UpdateDate()
	se.db.UpdateDate()
	return true
}

// SaveScript adds a script to a schema, or replaces the one at position at (use -1 to add).
func (se *SchemaEditor) SaveScript(schemaIndex, at int, s *models.Script) error {
	schema, err := se.schemaAt(schemaIndex)
	if err != nil {
		return err
	}
	s.Name = strings.TrimSpace(s.Name)
	if s.Name == "" {
		return errors.New("script name is required")
	}
	if strings.TrimSpace(s.SQL) == "" {
		return errors.New("script SQL is required")
	}
	for i, o := range schema.Scripts {
		if i != at && o.Name == s.Name {
			return fmt.Errorf("script %q already exists", s.Name)
		}
	}
	s.Schema = schema.Name
	if at >= 0 && at < len(schema.Scripts) {
		schema.Scripts[at] = s
	} else {
		schema.Scripts = append(schema.Scripts, s)
	}
	schema.UpdateDate()
	se.db.UpdateDate()
	return nil
}

// DeleteScript removes the script at position at.
func (se *SchemaEditor) DeleteScript(schemaIndex, at int) bool {
	schema, err := se.schemaAt(schemaIndex)
	if err != nil || at < 0 || at >= len(schema.Scripts) {
		return false
	}
	schema.Scripts = append(schema.Scripts[:at], schema.Scripts[at+1:]...)
	schema.UpdateDate()
	se.db.UpdateDate()
	return true
}

// AssignTableToDomain adds a reference to schemaName.tableName to the domain at domainIndex.
func (se *SchemaEditor) AssignTableToDomain(domainIndex int, schemaName, tableName string) error {
	if domainIndex < 0 || domainIndex >= len(se.db.Domains) {
		return errors.New("domain not found")
	}
	domain := se.db.Domains[domainIndex]
	var table *models.Table
	for _, s := range se.db.Schemas {
		if s.Name != schemaName {
			continue
		}
		for _, t := range s.Tables {
			if t.Name == tableName {
				table = t
			}
		}
	}
	if table == nil {
		return fmt.Errorf("table %s.%s not found", schemaName, tableName)
	}
	for _, dt := range domain.Tables {
		if dt.SchemaName == schemaName && dt.TableName == tableName {
			return fmt.Errorf("table %s.%s is already in domain %s", schemaName, tableName, domain.Name)
		}
	}
	dt := models.InitDomainTable(tableName, schemaName)
	dt.RefTable = table
	dt.Sequence = uint(len(domain.Tables))
	domain.Tables = append(domain.Tables, dt)
	se.db.UpdateDate()
	return nil
}

// UnassignTableFromDomain removes the reference to schemaName.tableName from the domain.
func (se *SchemaEditor) UnassignTableFromDomain(domainIndex int, schemaName, tableName string) bool {
	if domainIndex < 0 || domainIndex >= len(se.db.Domains) {
		return false
	}
	domain := se.db.Domains[domainIndex]
	for i, dt := range domain.Tables {
		if dt.SchemaName == schemaName && dt.TableName == tableName {
			domain.Tables = append(domain.Tables[:i], domain.Tables[i+1:]...)
			se.db.UpdateDate()
			return true
		}
	}
	return false
}