feat(stats): split repos public/private + 7-day daily commit series

Collector now reports repos_public/repos_private (repos kept as the sum)
and a commits_daily[] series of 7 {date,commits} buckets (UTC days,
zero-filled), bucketed in Go from raw created_unix to avoid MySQL
session-timezone ambiguity. commits_7d is now the sum of those buckets
so the card total matches the sparkline.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

README.md

@@ -12,8 +12,33 @@ A tiny Go service that periodically snapshots Gitea instance metrics from a
 metrics card. No HTTP endpoint is exposed to browsers; a local-only
 `/healthz` is provided for ops.
 
-Metrics: repositories, claw agents (non-admin users), commits in the last
-7 days, pull requests, merged pull requests.
+Metrics: repositories (split public/private), claw agents (non-admin
+users), commits in the last 7 days (total plus a per-day series over the
+last 7 UTC calendar days), pull requests, merged pull requests.
+
+### Output schema (`stats.json`)
+
+```json
+{
+  "repos": 42,
+  "repos_public": 30,
+  "repos_private": 12,
+  "agents": 7,
+  "commits_7d": 91,
+  "commits_daily": [
+    {"date": "2026-05-22", "commits": 10},
+    {"date": "2026-05-23", "commits": 14}
+    // … 7 entries total, oldest → newest (UTC days)
+  ],
+  "prs": 18,
+  "merged": 12,
+  "generated_at": "2026-05-28T00:00:00Z",
+  "interval_hours": 12
+}
+```
+
+`commits_7d` equals the sum of `commits_daily` (7 calendar days, UTC), so
+the card total always matches the sparkline.
 
 ### Configuration (all via environment variables — no secrets in the image)
 
@@ -31,7 +56,7 @@ refresh it keeps the previous output (stale-while-error).
 
 ```sh
 # from repo root
-IMAGE=git.hangman-lab.top/hzhang/gitea-stats TAG=0.1.0 ./publish.sh
+IMAGE=git.hangman-lab.top/hzhang/gitea-stats TAG=0.2.0 ./publish.sh
 ```
 
 ### Run
@@ -42,7 +67,7 @@ docker run -d --name git-kc-stats \
   -e STATS_DB_DSN='gitea_ro:***@tcp(mysql:3306)/giteadb?timeout=5s&readTimeout=10s&loc=UTC' \
   -e STATS_INTERVAL=12h \
   -v /var/lib/gitea/custom/public/assets:/out \
-  git.hangman-lab.top/hzhang/gitea-stats:0.1.0
+  git.hangman-lab.top/hzhang/gitea-stats:0.2.0
 ```
 
 > The read-only MySQL user (`gitea_ro`, `SELECT` only on `giteadb`) and its

stats/main.go

@@ -20,14 +20,23 @@ import (
 	_ "github.com/go-sql-driver/mysql"
 )
 
+// DailyCommit is one bucket of the last-7-days commit series (UTC days).
+type DailyCommit struct {
+	Date    string `json:"date"` // YYYY-MM-DD (UTC)
+	Commits int64  `json:"commits"`
+}
+
 type Stats struct {
-	Repos       int64  `json:"repos"`
-	Agents      int64  `json:"agents"`
-	Commits7d   int64  `json:"commits_7d"`
-	PRs         int64  `json:"prs"`
-	Merged      int64  `json:"merged"`
-	GeneratedAt string `json:"generated_at"`
-	IntervalH   int    `json:"interval_hours"`
+	Repos        int64         `json:"repos"` // public + private
+	ReposPublic  int64         `json:"repos_public"`
+	ReposPrivate int64         `json:"repos_private"`
+	Agents       int64         `json:"agents"`
+	Commits7d    int64         `json:"commits_7d"` // sum of CommitsDaily
+	CommitsDaily []DailyCommit `json:"commits_daily"`
+	PRs          int64         `json:"prs"`
+	Merged       int64         `json:"merged"`
+	GeneratedAt  string        `json:"generated_at"`
+	IntervalH    int           `json:"interval_hours"`
 }
 
 var (
@@ -56,18 +65,59 @@ func collect(dsn string, interval time.Duration) (*Stats, error) {
 	var s Stats
 	err = db.QueryRowContext(ctx, `
 SELECT
- (SELECT COUNT(*) FROM repository),
+ (SELECT COUNT(*) FROM repository WHERE is_private=0),
+ (SELECT COUNT(*) FROM repository WHERE is_private=1),
  (SELECT COUNT(*) FROM user WHERE type=0 AND is_admin=0),
- (SELECT COALESCE(SUM(CASE WHEN JSON_VALID(content)
-        THEN COALESCE(JSON_LENGTH(content,'$.Commits'),0) ELSE 0 END),0)
-    FROM action
-   WHERE op_type=5 AND created_unix > UNIX_TIMESTAMP()-604800),
  (SELECT COUNT(*) FROM pull_request),
  (SELECT COUNT(*) FROM pull_request WHERE has_merged=1)
-`).Scan(&s.Repos, &s.Agents, &s.Commits7d, &s.PRs, &s.Merged)
+`).Scan(&s.ReposPublic, &s.ReposPrivate, &s.Agents, &s.PRs, &s.Merged)
 	if err != nil {
 		return nil, err
 	}
+	s.Repos = s.ReposPublic + s.ReposPrivate
+
+	// Per-day commit counts for the last 7 calendar days (UTC), oldest first.
+	// We pull raw (created_unix, commit_count) rows and bucket them in Go to
+	// avoid any dependence on the MySQL session time zone in date functions.
+	now := time.Now().UTC()
+	today := time.Date(now.Year(), now.Month(), now.Day(), 0, 0, 0, 0, time.UTC)
+	start := today.AddDate(0, 0, -6) // 7 buckets: start .. today
+	startUnix := start.Unix()
+
+	rows, err := db.QueryContext(ctx, `
+SELECT created_unix,
+       CASE WHEN JSON_VALID(content)
+            THEN COALESCE(JSON_LENGTH(content,'$.Commits'),0) ELSE 0 END
+  FROM action
+ WHERE op_type=5 AND created_unix >= ?`, startUnix)
+	if err != nil {
+		return nil, err
+	}
+	defer rows.Close()
+
+	daily := make([]int64, 7)
+	for rows.Next() {
+		var cu, c int64
+		if err := rows.Scan(&cu, &c); err != nil {
+			return nil, err
+		}
+		if idx := int((cu - startUnix) / 86400); idx >= 0 && idx < 7 {
+			daily[idx] += c
+		}
+	}
+	if err := rows.Err(); err != nil {
+		return nil, err
+	}
+
+	s.CommitsDaily = make([]DailyCommit, 7)
+	for i := 0; i < 7; i++ {
+		s.CommitsDaily[i] = DailyCommit{
+			Date:    start.AddDate(0, 0, i).Format("2006-01-02"),
+			Commits: daily[i],
+		}
+		s.Commits7d += daily[i]
+	}
+
 	s.GeneratedAt = time.Now().UTC().Format(time.RFC3339)
 	s.IntervalH = int(interval / time.Hour)
 	return &s, nil
@@ -99,8 +149,8 @@ func refresh(dsn, out string, interval time.Duration) {
 	mu.Lock()
 	last = s
 	mu.Unlock()
-	log.Printf("ok repos=%d agents=%d commits_7d=%d prs=%d merged=%d",
-		s.Repos, s.Agents, s.Commits7d, s.PRs, s.Merged)
+	log.Printf("ok repos=%d (pub=%d priv=%d) agents=%d commits_7d=%d prs=%d merged=%d",
+		s.Repos, s.ReposPublic, s.ReposPrivate, s.Agents, s.Commits7d, s.PRs, s.Merged)
 }
 
 func main() {