appview: db: introduce punchcard table

tracks commit per user by day

Signed-off-by: oppiliappan <[e-mail]>

appview/db/db.go

···
 			expiry text not null
 		);
 
+		create table if not exists punchcard (
+			did text not null,
+			date text not null, -- yyyy-mm-dd
+			count integer,
+			primary key (did, date)
+		);
+
 		create table if not exists migrations (
 			id integer primary key autoincrement,
 			name text unique
···
 		key: key,
 		arg: arg,
 		cmp: "<>",
+	}
+}
+
+func FilterGte(key string, arg any) filter {
+	return filter{
+		key: key,
+		arg: arg,
+		cmp: ">=",
+	}
+}
+
+func FilterLte(key string, arg any) filter {
+	return filter{
+		key: key,
+		arg: arg,
+		cmp: "<=",
 	}
 }
 

appview/db/punchcard.go

···
+package db
+
+import (
+	"database/sql"
+	"fmt"
+	"strings"
+	"time"
+)
+
+type Punch struct {
+	Did   string
+	Date  time.Time
+	Count int
+}
+
+// this adds to the existing count
+func AddPunch(e Execer, punch Punch) error {
+	_, err := e.Exec(`
+		insert into punchcard (did, date, count)
+		values (?, ?, ?)
+			on conflict(did, date) do update set
+			count = coalesce(punchcard.count, 0) + excluded.count;
+	`, punch.Did, punch.Date.Format(time.DateOnly), punch.Count)
+	return err
+}
+
+type Punchcard struct {
+	Total   int
+	Punches []Punch
+}
+
+func MakePunchcard(e Execer, filters ...filter) (Punchcard, error) {
+	punchcard := Punchcard{}
+	now := time.Now()
+	startOfYear := time.Date(now.Year(), 1, 1, 0, 0, 0, 0, time.UTC)
+	endOfYear := time.Date(now.Year(), 12, 31, 0, 0, 0, 0, time.UTC)
+	for d := startOfYear; d.Before(endOfYear) || d.Equal(endOfYear); d = d.AddDate(0, 0, 1) {
+		punchcard.Punches = append(punchcard.Punches, Punch{
+			Date:  d,
+			Count: 0,
+		})
+	}
+
+	var conditions []string
+	var args []any
+	for _, filter := range filters {
+		conditions = append(conditions, filter.Condition())
+		args = append(args, filter.arg)
+	}
+
+	whereClause := ""
+	if conditions != nil {
+		whereClause = " where " + strings.Join(conditions, " and ")
+	}
+
+	query := fmt.Sprintf(`
+		select date, sum(count) as total_count
+		from punchcard
+		%s
+		group by date
+		order by date
+		`, whereClause)
+
+	rows, err := e.Query(query, args...)
+	if err != nil {
+		return punchcard, err
+	}
+	defer rows.Close()
+
+	for rows.Next() {
+		var punch Punch
+		var date string
+		var count sql.NullInt64
+		if err := rows.Scan(&date, &count); err != nil {
+			return punchcard, err
+		}
+
+		punch.Date, err = time.Parse(time.DateOnly, date)
+		if err != nil {
+			fmt.Println("invalid date")
+			// this punch is not recorded if date is invalid
+			continue
+		}
+
+		if count.Valid {
+			punch.Count = int(count.Int64)
+		}
+
+		punchcard.Punches[punch.Date.YearDay()] = punch
+		punchcard.Total += punch.Count
+	}
+
+	return punchcard, nil
+}