package postgres

import (
	"context"
	"database/sql"
	"errors"
	"fmt"
	"git.aiterp.net/rpdata/api/database/postgres/psqlcore"
	"git.aiterp.net/rpdata/api/models"
	"strconv"
	"strings"
)

var ErrNickConflict = errors.New("nick already in use by another character")

type characterRepository struct {
	insertWithIDs bool
	db            *sql.DB
}

func (r *characterRepository) Find(ctx context.Context, id string) (*models.Character, error) {
	row, err := psqlcore.New(r.db).SelectCharacterByID(ctx, id)
	if err != nil {
		return nil, err
	}

	return r.character(row), nil
}

func (r *characterRepository) FindNick(ctx context.Context, nick string) (*models.Character, error) {
	row, err := psqlcore.New(r.db).SelectCharacterByNick(ctx, nick)
	if err != nil {
		return nil, err
	}

	return r.character(psqlcore.SelectCharacterByIDRow(row)), nil
}

func (r *characterRepository) FindName(ctx context.Context, name string) (*models.Character, error) {
	row, err := psqlcore.New(r.db).SelectCharacterByName(ctx, name)
	if err != nil {
		return nil, err
	}

	return r.character(psqlcore.SelectCharacterByIDRow(row)), nil
}

func (r *characterRepository) List(ctx context.Context, filter models.CharacterFilter) ([]*models.Character, error) {
	params := psqlcore.SelectCharactersParams{
		LimitSize: 0,
	}

	if filter.IDs != nil {
		params.FilterID = true
		params.Ids = filter.IDs
	}
	if filter.Nicks != nil {
		params.FilterNick = true
		params.Nicks = filter.Nicks
	}
	if filter.Names != nil {
		params.FilterName = true
		params.Names = filter.Names
	}
	if filter.Author != nil {
		params.FilterAuthor = true
		params.Author = *filter.Author
	}
	if filter.Search != nil {
		params.FilterSearch = true
		params.Search = TSQueryFromSearch(*filter.Search)
	}
	if filter.Limit > 0 {
		params.LimitSize = int32(filter.Limit)
	}

	rows, err := psqlcore.New(r.db).SelectCharacters(ctx, params)
	if err != nil {
		return nil, err
	}

	return r.characters(rows), nil
}

func (r *characterRepository) Insert(ctx context.Context, character models.Character) (*models.Character, error) {
	tx, err := r.db.BeginTx(ctx, nil)
	if err != nil {
		return nil, err
	}
	defer func() { _ = tx.Rollback() }()
	q := psqlcore.New(tx)

	if !r.insertWithIDs || character.ID == "" {
		next, err := q.IncrementCounter(ctx, "data_character_id")
		if err != nil {
			return nil, err
		}

		character.ID = fmt.Sprintf("C%d", next)
	} else {
		n, err := strconv.Atoi(character.ID[1:])
		if err != nil {
			return nil, err
		}

		err = q.BumpCounter(ctx, psqlcore.BumpCounterParams{ID: "data_character_id", Value: int32(n)})
		if err != nil {
			return nil, err
		}
	}

	rows, err := q.SelectCharacters(ctx, psqlcore.SelectCharactersParams{
		FilterNick: true,
		Nicks:      character.Nicks,
		LimitSize:  1,
	})
	if err != nil {
		return nil, fmt.Errorf("failed to select: %s", err)
	}
	if len(rows) != 0 {
		return nil, ErrNickConflict
	}

	err = q.InsertCharacter(ctx, psqlcore.InsertCharacterParams{
		ID:          character.ID,
		Nicks:       character.Nicks,
		Name:        character.Name,
		ShortName:   character.ShortName,
		Author:      character.Author,
		Description: character.Description,
	})
	if err != nil {
		return nil, err
	}

	err = tx.Commit()
	if err != nil {
		return nil, err
	}

	return &character, nil
}

func (r *characterRepository) Update(ctx context.Context, character models.Character, update models.CharacterUpdate) (*models.Character, error) {
	character.ApplyUpdate(update)

	err := psqlcore.New(r.db).UpdateCharacter(ctx, psqlcore.UpdateCharacterParams{
		ID:          character.ID,
		Name:        character.Name,
		ShortName:   character.ShortName,
		Description: character.Description,
	})
	if err != nil {
		return nil, err
	}

	return &character, nil
}

func (r *characterRepository) AddNick(ctx context.Context, character models.Character, nick string) (*models.Character, error) {
	tx, err := r.db.BeginTx(ctx, nil)
	if err != nil {
		return nil, err
	}
	defer func() { _ = tx.Rollback() }()

	q := psqlcore.New(tx)

	rows, err := q.SelectCharacters(ctx, psqlcore.SelectCharactersParams{
		FilterNick: true,
		Nicks:      []string{nick},
		LimitSize:  1,
	})
	if err != nil {
		return nil, err
	}
	if len(rows) != 0 {
		return nil, ErrNickConflict
	}

	err = q.AddCharacterNick(ctx, psqlcore.AddCharacterNickParams{ID: character.ID, Nick: nick})
	if err != nil {
		return nil, err
	}

	character.Nicks = append(character.Nicks, nick)

	err = tx.Commit()
	if err != nil {
		return nil, err
	}

	return &character, nil
}

func (r *characterRepository) RemoveNick(ctx context.Context, character models.Character, nick string) (*models.Character, error) {
	err := psqlcore.New(r.db).RemoveCharacterNick(ctx, psqlcore.RemoveCharacterNickParams{ID: character.ID, Nick: nick})
	if err != nil {
		return nil, err
	}

	for i, nick2 := range character.Nicks {
		if nick2 == nick {
			character.Nicks = append(character.Nicks[:i], character.Nicks[i+1:]...)
			break
		}
	}

	return &character, nil
}

func (r *characterRepository) Delete(ctx context.Context, character models.Character) error {
	return psqlcore.New(r.db).DeleteCharacter(ctx, character.ID)
}

func (r *characterRepository) character(row psqlcore.SelectCharacterByIDRow) *models.Character {
	return &models.Character{
		ID:          strings.Trim(row.ID, " "),
		Nicks:       row.Nicks,
		Name:        row.Name,
		ShortName:   row.ShortName,
		Author:      row.Author,
		Description: row.Description,
	}
}

func (r *characterRepository) characters(rows []psqlcore.SelectCharactersRow) []*models.Character {
	results := make([]*models.Character, 0, len(rows))
	for _, row := range rows {
		results = append(results, r.character(psqlcore.SelectCharacterByIDRow(row)))
	}

	return results
}