package postgres

import (
	"database/sql"

	"gardomatic.kleiax.de/internal/storage"
)

// TaskPriorityModel implements storage.TaskPriorityModelInterface for the
// application-wide priority catalogue.
type TaskPriorityModel struct{ DB *sql.DB }

func scanTaskPriority(s scanner) (storage.TaskPriority, error) {
	var priority storage.TaskPriority
	err := s.Scan(&priority.ID, &priority.Name, &priority.Value, &priority.SortOrder, &priority.Active, &priority.CreatedAt, &priority.UpdatedAt, &priority.Version)
	return priority, err
}

// Insert creates a priority catalogue entry.
func (m TaskPriorityModel) Insert(priority storage.TaskPriority) (storage.TaskPriority, error) {
	ctx, cancel := contextWithTimeout()
	defer cancel()
	err := m.DB.QueryRowContext(ctx, `INSERT INTO task_priorities (name, value, sort_order, active) VALUES ($1,$2,$3,$4) RETURNING id, created_at, updated_at, version`, priority.Name, priority.Value, priority.SortOrder, priority.Active).Scan(&priority.ID, &priority.CreatedAt, &priority.UpdatedAt, &priority.Version)
	if err != nil {
		return storage.TaskPriority{}, recordError(err)
	}
	return priority, nil
}

// Get returns a priority catalogue entry by ID.
func (m TaskPriorityModel) Get(id int) (storage.TaskPriority, error) {
	ctx, cancel := contextWithTimeout()
	defer cancel()
	priority, err := scanTaskPriority(m.DB.QueryRowContext(ctx, `SELECT id,name,value,sort_order,active,created_at,updated_at,version FROM task_priorities WHERE id=$1`, id))
	if err != nil {
		return storage.TaskPriority{}, recordError(err)
	}
	return priority, nil
}

// GetAll lists all priority catalogue entries in display order.
func (m TaskPriorityModel) GetAll() ([]storage.TaskPriority, error) {
	ctx, cancel := contextWithTimeout()
	defer cancel()
	rows, err := m.DB.QueryContext(ctx, `SELECT id,name,value,sort_order,active,created_at,updated_at,version FROM task_priorities ORDER BY sort_order, value, id`)
	if err != nil {
		return nil, err
	}
	defer rows.Close()
	result := []storage.TaskPriority{}
	for rows.Next() {
		value, err := scanTaskPriority(rows)
		if err != nil {
			return nil, err
		}
		result = append(result, value)
	}
	return result, rows.Err()
}

// Update changes a priority catalogue entry using optimistic locking.
func (m TaskPriorityModel) Update(priority storage.TaskPriority) (storage.TaskPriority, error) {
	ctx, cancel := contextWithTimeout()
	defer cancel()
	err := m.DB.QueryRowContext(ctx, `UPDATE task_priorities SET name=$1,value=$2,sort_order=$3,active=$4,updated_at=CURRENT_TIMESTAMP,version=version+1 WHERE id=$5 AND version=$6 RETURNING updated_at,version`, priority.Name, priority.Value, priority.SortOrder, priority.Active, priority.ID, priority.Version).Scan(&priority.UpdatedAt, &priority.Version)
	if err == sql.ErrNoRows {
		return storage.TaskPriority{}, storage.ErrEditConflict
	}
	if err != nil {
		return storage.TaskPriority{}, recordError(err)
	}
	return priority, nil
}