package mysqldriver

import (
	"context"
	"database/sql"
	"git.aiterp.net/stufflog/server/internal/generate"
	"git.aiterp.net/stufflog/server/internal/slerrors"
	"git.aiterp.net/stufflog/server/models"
	sq "github.com/Masterminds/squirrel"
	"github.com/jmoiron/sqlx"
)

type logRepository struct {
	db *sqlx.DB
}

func (r *logRepository) Find(ctx context.Context, id string) (*models.Log, error) {
	log := models.Log{}
	err := r.db.GetContext(ctx, &log, "SELECT * FROM log WHERE log_id=?", id)
	if err != nil {
		if err == sql.ErrNoRows {
			return nil, slerrors.NotFound("Log")
		}

		return nil, err
	}

	err = r.db.SelectContext(ctx, &log.Items, "SELECT * FROM log_item WHERE log_id=?", id)
	if err != nil {
		return nil, err
	}
	err = r.db.SelectContext(ctx, &log.Tasks, "SELECT * FROM log_task WHERE log_id=?", id)
	if err != nil {
		return nil, err
	}

	return &log, nil
}

func (r *logRepository) List(ctx context.Context, filter models.LogFilter) ([]*models.Log, error) {
	q := sq.Select("log.*").From("log").GroupBy("log.log_id").OrderBy("log.date")
	if len(filter.IssueItemIDs) > 0 || len(filter.IssueIDs) > 0 {
		q = q.LeftJoin("log_item ON log_item.log_id = log.log_id")
	}
	if len(filter.IssueTaskIDs) > 0 || len(filter.IssueIDs) > 0 {
		q = q.LeftJoin("log_task ON log_task.log_id = log.log_id")
	}
	if len(filter.IssueIDs) > 0 {
		q = q.Where(sq.Or{
			sq.Eq{"log_task.issue_id": filter.IssueIDs},
			sq.Eq{"log_item.issue_id": filter.IssueIDs},
		})
	}
	if len(filter.IssueItemIDs) > 0 {
		q = q.Where(sq.Eq{"log_item.issue_item_id": filter.IssueItemIDs})
	}
	if len(filter.IssueTaskIDs) > 0 {
		q = q.Where(sq.Eq{"log_task.issue_task_id": filter.IssueTaskIDs})
	}
	if len(filter.LogIDs) > 0 {
		q = q.Where(sq.Eq{"log.log_id": filter.LogIDs})
	}
	if len(filter.UserIDs) > 0 {
		q = q.Where(sq.Eq{"log.user_id": filter.UserIDs})
	}
	if filter.FromDate != nil {
		q = q.Where(sq.GtOrEq{"log.date": *filter.FromDate})
	}
	if filter.ToDate != nil {
		q = q.Where(sq.LtOrEq{"log.date": *filter.ToDate})
	}

	query, args, err := q.ToSql()
	if err != nil {
		return nil, err
	}

	results := make([]*models.Log, 0, 16)
	err = r.db.SelectContext(ctx, &results, query, args...)
	if err != nil {
		if err == sql.ErrNoRows {
			return []*models.Log{}, nil
		}

		return nil, err
	}

	err = r.fill(ctx, results)
	if err != nil {
		return nil, err
	}

	return results, nil
}

func (r *logRepository) Insert(ctx context.Context, log models.Log) (*models.Log, error) {
	tx, err := r.db.BeginTxx(ctx, nil)
	if err != nil {
		return nil, err
	}

	log.ID = generate.LogID()

	_, err = tx.NamedExecContext(ctx, `
		INSERT INTO log (
    		log_id, user_id, date, description
    	) VALUES (
    		:log_id, :user_id, :date, :description	
    	)
	`, log)
	if err != nil {
		_ = tx.Rollback()
		return nil, err
	}

	for _, item := range log.Items {
		item.LogID = log.ID
		_, err = tx.NamedExecContext(ctx, `
			INSERT INTO log_item (
				log_id, issue_id, issue_item_id, amount
			) VALUES (
				:log_id, :issue_id, :issue_item_id, :amount
			)
		`, item)
		if err != nil {
			_ = tx.Rollback()
			return nil, err
		}
	}
	for _, task := range log.Tasks {
		task.LogID = log.ID
		_, err = tx.NamedExecContext(ctx, `
			INSERT INTO log_task (
				log_id, issue_id, issue_task_id, units, duration
			) VALUES (
				:log_id, :issue_id, :issue_task_id, :units, :duration
			)
		`, task)
		if err != nil {
			_ = tx.Rollback()
			return nil, err
		}
	}

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

	return &log, nil
}

func (r *logRepository) Save(ctx context.Context, log models.Log) error {
	tx, err := r.db.BeginTxx(ctx, nil)
	if err != nil {
		return err
	}

	_, err = tx.NamedExecContext(ctx, `
		UPDATE log SET
			date=:date,
			description=:description
		WHERE log_id=:log_id
	`, log)
	if err != nil {
		_ = tx.Rollback()
		return err
	}

	_, err = tx.ExecContext(ctx, "DELETE FROM log_item WHERE log_id=?", log.ID)
	if err != nil {
		_ = tx.Rollback()
		return err
	}
	_, err = tx.ExecContext(ctx, "DELETE FROM log_task WHERE log_id=?", log.ID)
	if err != nil {
		_ = tx.Rollback()
		return err
	}

	for _, item := range log.Items {
		_, err = tx.NamedExecContext(ctx, `
			INSERT INTO log_item (
				log_id, issue_id, issue_item_id, amount
			) VALUES (
				:log_id, :issue_id, :issue_item_id, :amount
			)
		`, item)
		if err != nil {
			_ = tx.Rollback()
			return err
		}
	}
	for _, task := range log.Tasks {
		_, err = tx.NamedExecContext(ctx, `
			INSERT INTO log_task (
				log_id, issue_id, issue_task_id, units, duration
			) VALUES (
				:log_id, :issue_id, :issue_task_id, :units, :duration
			)
		`, task)
		if err != nil {
			_ = tx.Rollback()
			return err
		}
	}

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

	return nil
}

func (r *logRepository) Delete(ctx context.Context, log models.Log) error {
	tx, err := r.db.BeginTxx(ctx, nil)
	if err != nil {
		return err
	}

	_, err = tx.ExecContext(ctx, "DELETE FROM log WHERE log_id=?", log.ID)
	if err != nil {
		_ = tx.Rollback()
		return err
	}
	_, err = tx.ExecContext(ctx, "DELETE FROM log_item WHERE log_id=?", log.ID)
	if err != nil {
		_ = tx.Rollback()
		return err
	}
	_, err = tx.ExecContext(ctx, "DELETE FROM log_task WHERE log_id=?", log.ID)
	if err != nil {
		_ = tx.Rollback()
		return err
	}

	return tx.Commit()
}

func (r *logRepository) fill(ctx context.Context, logs []*models.Log) error {
	logMap := make(map[string]int, len(logs))
	ids := make([]string, len(logs))
	for i, log := range logs {
		ids[i] = log.ID
		logMap[log.ID] = i
	}

	itemsQuery, itemsArgs, err := sq.Select("*").From("log_item").Where(sq.Eq{"log_id": ids}).ToSql()
	if err != nil {
		return err
	}
	tasksQuery, tasksArgs, err := sq.Select("*").From("log_task").Where(sq.Eq{"log_id": ids}).ToSql()
	if err != nil {
		return err
	}

	items := make([]models.LogItem, 0, len(logs)*3)
	err = r.db.SelectContext(ctx, &items, itemsQuery, itemsArgs...)
	if err != nil {
		return err
	}
	for _, item := range items {
		log := logs[logMap[item.LogID]]
		log.Items = append(log.Items, item)
	}

	tasks := make([]models.LogTask, 0, len(logs)*3)
	err = r.db.SelectContext(ctx, &tasks, tasksQuery, tasksArgs...)
	if err != nil {
		return err
	}
	for _, task := range tasks {
		log := logs[logMap[task.LogID]]
		log.Tasks = append(log.Tasks, task)
	}

	return nil
}