package quotedb

import (
	"database/sql"
	"errors"
)

// TODO(lupine): Much of the contents here can be replaced with sqlx, in time

type Quote struct {
	Id        int // Unique among all quotes
	QuoteId   int // Unique within a particular channel
	Channel   string
	Data      string
	Author    string
	CreatedAt NullTime
	DeletedAt NullTime
	DeletedBy sql.NullString
}

var (
	SCHEMA = `
	create table if not exists quotes(
		id integer not null primary key,
		quote_id integer not null,
		channel string not null,
		data text not null,
		author text not null,
		created_at timestamp,
		deleted_at timestamp,
		deleted_by string
	);
	create index if not exists quotes_by_channel      on quotes(channel);
	create index if not exists quotes_by_deleted_at   on quotes(deleted_at);
	create index if not exists quotes_by_data         on quotes(data);
	create unique index if not exists unique_quotes_by_channel_and_quote_id on quotes(channel, quote_id);
	`

	quoteCols = `id,quote_id,channel,data,author,created_at,deleted_at,deleted_by`

	findQuoteById      = `SELECT ` + quoteCols + ` FROM quotes WHERE id = ? LIMIT 1`
	findQuoteByQuoteId = `SELECT ` + quoteCols + ` FROM quotes WHERE quote_id = ? AND channel = ? LIMIT 1`
	findLastQuote      = `SELECT ` + quoteCols + ` FROM quotes WHERE channel = ? ORDER BY quote_id DESC LIMIT 1`
	findQuotesByTerm   = `SELECT ` + quoteCols + ` FROM quotes WHERE channel = ? AND data LIKE ? ORDER BY quote_id DESC`
	findRandomQuote    = `SELECT ` + quoteCols + ` FROM quotes WHERE deleted_at IS NULL AND channel = ? ORDER BY  RANDOM() LIMIT 1`

	insertQuote = `
	INSERT INTO quotes (
		channel,
		quote_id,
		data,
		author,
		created_at
	) SELECT
		$1,
		ifnull(max(quote_id),0)+1,
		$2,
		$3,
		$4
		FROM quotes WHERE channel = $1;
		`

	errInsertIdUnknown = errors.New("SQL: Couldn't determine insert ID")
)

// urgh. Code reuse. Not.
func scanQuotesRows(rows *sql.Rows) (*Quote, error) {
	var quote Quote

	err := rows.Scan(
		&quote.Id, &quote.QuoteId, &quote.Channel, &quote.Data, &quote.Author,
		&quote.CreatedAt, &quote.DeletedAt, &quote.DeletedBy,
	)

	return &quote, err
}

func scanQuotesRow(row *sql.Row) (*Quote, error) {
	var quote Quote

	err := row.Scan(
		&quote.Id, &quote.QuoteId, &quote.Channel, &quote.Data, &quote.Author,
		&quote.CreatedAt, &quote.DeletedAt, &quote.DeletedBy)

	return &quote, err
}