ez-api/internal/api/log_handler.go

package api

import (
	"net/http"
	"strconv"
	"strings"
	"time"

	"github.com/ez-api/ez-api/internal/model"
	"github.com/gin-gonic/gin"
	"gorm.io/gorm"
)

type LogView struct {
	ID           uint   `json:"id"`
	CreatedAt    int64  `json:"created_at"`
	Group        string `json:"group"`
	KeyID        uint   `json:"key_id"`
	ModelName    string `json:"model"`
	ProviderID   uint   `json:"provider_id"`
	ProviderType string `json:"provider_type"`
	ProviderName string `json:"provider_name"`
	StatusCode   int    `json:"status_code"`
	LatencyMs    int64  `json:"latency_ms"`
	TokensIn     int64  `json:"tokens_in"`
	TokensOut    int64  `json:"tokens_out"`
	ErrorMessage string `json:"error_message"`
	ClientIP     string `json:"client_ip"`
	RequestSize  int64  `json:"request_size"`
	ResponseSize int64  `json:"response_size"`
	AuditReason  string `json:"audit_reason"`
	RequestBody  string `json:"request_body,omitempty"`
}

func toLogView(r model.LogRecord) LogView {
	return LogView{
		ID:           r.ID,
		CreatedAt:    r.CreatedAt.UTC().Unix(),
		Group:        r.Group,
		KeyID:        r.KeyID,
		ModelName:    r.ModelName,
		ProviderID:   r.ProviderID,
		ProviderType: r.ProviderType,
		ProviderName: r.ProviderName,
		StatusCode:   r.StatusCode,
		LatencyMs:    r.LatencyMs,
		TokensIn:     r.TokensIn,
		TokensOut:    r.TokensOut,
		ErrorMessage: r.ErrorMessage,
		ClientIP:     r.ClientIP,
		RequestSize:  r.RequestSize,
		ResponseSize: r.ResponseSize,
		AuditReason:  r.AuditReason,
		RequestBody:  r.RequestBody,
	}
}

type MasterLogView struct {
	ID           uint   `json:"id"`
	CreatedAt    int64  `json:"created_at"`
	Group        string `json:"group"`
	KeyID        uint   `json:"key_id"`
	ModelName    string `json:"model"`
	StatusCode   int    `json:"status_code"`
	LatencyMs    int64  `json:"latency_ms"`
	TokensIn     int64  `json:"tokens_in"`
	TokensOut    int64  `json:"tokens_out"`
	ErrorMessage string `json:"error_message"`
	RequestSize  int64  `json:"request_size"`
	ResponseSize int64  `json:"response_size"`
}

func toMasterLogView(r model.LogRecord) MasterLogView {
	return MasterLogView{
		ID:           r.ID,
		CreatedAt:    r.CreatedAt.UTC().Unix(),
		Group:        r.Group,
		KeyID:        r.KeyID,
		ModelName:    r.ModelName,
		StatusCode:   r.StatusCode,
		LatencyMs:    r.LatencyMs,
		TokensIn:     r.TokensIn,
		TokensOut:    r.TokensOut,
		ErrorMessage: r.ErrorMessage,
		RequestSize:  r.RequestSize,
		ResponseSize: r.ResponseSize,
	}
}

type ListLogsResponse struct {
	Total  int64     `json:"total"`
	Limit  int       `json:"limit"`
	Offset int       `json:"offset"`
	Items  []LogView `json:"items"`
}

type ListMasterLogsResponse struct {
	Total  int64           `json:"total"`
	Limit  int             `json:"limit"`
	Offset int             `json:"offset"`
	Items  []MasterLogView `json:"items"`
}

func parseLimitOffset(c *gin.Context) (limit, offset int) {
	limit = 50
	offset = 0
	if raw := strings.TrimSpace(c.Query("limit")); raw != "" {
		if v, err := strconv.Atoi(raw); err == nil && v > 0 {
			limit = v
		}
	}
	if limit > 200 {
		limit = 200
	}
	if raw := strings.TrimSpace(c.Query("offset")); raw != "" {
		if v, err := strconv.Atoi(raw); err == nil && v >= 0 {
			offset = v
		}
	}
	return limit, offset
}

func parseUnixSeconds(raw string) (time.Time, bool) {
	raw = strings.TrimSpace(raw)
	if raw == "" {
		return time.Time{}, false
	}
	sec, err := strconv.ParseInt(raw, 10, 64)
	if err != nil || sec <= 0 {
		return time.Time{}, false
	}
	return time.Unix(sec, 0).UTC(), true
}

func (h *MasterHandler) masterLogBase(masterID uint) (*gorm.DB, error) {
	logDB := h.logDBConn()
	base := h.logBaseQuery()
	if logDB == h.db {
		return base.
			Joins("JOIN keys ON keys.id = log_records.key_id").
			Where("keys.master_id = ?", masterID), nil
	}
	var keyIDs []uint
	if err := h.db.Model(&model.Key{}).
		Where("master_id = ?", masterID).
		Pluck("id", &keyIDs).Error; err != nil {
		return nil, err
	}
	if len(keyIDs) == 0 {
		return base.Where("1 = 0"), nil
	}
	return base.
		Where("log_records.key_id IN ?", keyIDs), nil
}

// ListLogs godoc
// @Summary      List logs (admin)
// @Description  List request logs with basic filtering/pagination. Returns full log records including request_body.
// @Tags         admin
// @Produce      json
// @Security     AdminAuth
// @Param        limit        query     int     false  "limit (default 50, max 200)"
// @Param        offset       query     int     false  "offset"
// @Param        since        query     int     false  "unix seconds"
// @Param        until        query     int     false  "unix seconds"
// @Param        key_id       query     int     false  "key id"
// @Param        group        query     string  false  "route group"
// @Param        model        query     string  false  "model"
// @Param        status_code  query     int     false  "status code"
// @Success      200  {object}  ListLogsResponse
// @Failure      500  {object}  gin.H
// @Router       /admin/logs [get]
func (h *Handler) ListLogs(c *gin.Context) {
	limit, offset := parseLimitOffset(c)

	q := h.logBaseQuery()

	if t, ok := parseUnixSeconds(c.Query("since")); ok {
		q = q.Where("created_at >= ?", t)
	}
	if t, ok := parseUnixSeconds(c.Query("until")); ok {
		q = q.Where("created_at <= ?", t)
	}
	if raw := strings.TrimSpace(c.Query("key_id")); raw != "" {
		if v, err := strconv.ParseUint(raw, 10, 64); err == nil && v > 0 {
			q = q.Where("key_id = ?", uint(v))
		}
	}
	if raw := strings.TrimSpace(c.Query("group")); raw != "" {
		q = q.Where(`"group" = ?`, raw)
	}
	if raw := strings.TrimSpace(c.Query("model")); raw != "" {
		q = q.Where("model_name = ?", raw)
	}
	if raw := strings.TrimSpace(c.Query("status_code")); raw != "" {
		if v, err := strconv.Atoi(raw); err == nil && v > 0 {
			q = q.Where("status_code = ?", v)
		}
	}

	var total int64
	if err := q.Count(&total).Error; err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"error": "failed to count logs", "details": err.Error()})
		return
	}

	var rows []model.LogRecord
	if err := q.Order("id desc").Limit(limit).Offset(offset).Find(&rows).Error; err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"error": "failed to list logs", "details": err.Error()})
		return
	}
	// Admin sees full LogView including request_body
	out := make([]LogView, 0, len(rows))
	for _, r := range rows {
		out = append(out, toLogView(r))
	}
	c.JSON(http.StatusOK, ListLogsResponse{Total: total, Limit: limit, Offset: offset, Items: out})
}

type LogStatsResponse struct {
	Total      int64            `json:"total"`
	TokensIn   int64            `json:"tokens_in"`
	TokensOut  int64            `json:"tokens_out"`
	AvgLatency float64          `json:"avg_latency_ms"`
	ByStatus   map[string]int64 `json:"by_status"`
}

// GroupedStatsItem represents a single group in grouped statistics
type GroupedStatsItem struct {
	// For group_by=model
	Model string `json:"model,omitempty"`
	// For group_by=day
	Date string `json:"date,omitempty"`
	// For group_by=month
	Month string `json:"month,omitempty"`
	// For group_by=hour
	Hour string `json:"hour,omitempty"`
	// For group_by=minute
	Minute string `json:"minute,omitempty"`

	Count        int64   `json:"count"`
	TokensIn     int64   `json:"tokens_in"`
	TokensOut    int64   `json:"tokens_out"`
	AvgLatencyMs float64 `json:"avg_latency_ms,omitempty"`
}

// GroupedStatsResponse is returned when group_by is specified
type GroupedStatsResponse struct {
	Items []GroupedStatsItem `json:"items"`
}

type DeleteLogsRequest struct {
	Before string `json:"before"`
	KeyID  uint   `json:"key_id"`
	Model  string `json:"model"`
}

type DeleteLogsResponse struct {
	DeletedCount int64 `json:"deleted_count"`
}

// DeleteLogs godoc
// @Summary      Delete logs (admin)
// @Description  Delete logs before a given timestamp with optional filters
// @Tags         admin
// @Accept       json
// @Produce      json
// @Security     AdminAuth
// @Param        request  body      DeleteLogsRequest  true  "Delete filters"
// @Success      200      {object}  DeleteLogsResponse
// @Failure      400      {object}  gin.H
// @Failure      500      {object}  gin.H
// @Router       /admin/logs [delete]
func (h *Handler) DeleteLogs(c *gin.Context) {
	var req DeleteLogsRequest
	if err := c.ShouldBindJSON(&req); err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": "invalid request body"})
		return
	}

	before := strings.TrimSpace(req.Before)
	if before == "" {
		c.JSON(http.StatusBadRequest, gin.H{"error": "before is required"})
		return
	}
	ts, err := time.Parse(time.RFC3339, before)
	if err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": "invalid before time"})
		return
	}

	deleted, err := h.deleteLogsBefore(ts.UTC(), req.KeyID, req.Model)
	if err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"error": "failed to delete logs", "details": err.Error()})
		return
	}
	c.JSON(http.StatusOK, DeleteLogsResponse{DeletedCount: deleted})
}

func (h *Handler) deleteLogsBefore(cutoff time.Time, keyID uint, modelName string) (int64, error) {
	modelName = strings.TrimSpace(modelName)
	if h == nil || h.logPartitioner == nil || !h.logPartitioner.Enabled() {
		q := h.logBaseQuery().Unscoped().Where("created_at < ?", cutoff)
		if keyID > 0 {
			q = q.Where("key_id = ?", keyID)
		}
		if modelName != "" {
			q = q.Where("model_name = ?", modelName)
		}
		res := q.Delete(&model.LogRecord{})
		return res.RowsAffected, res.Error
	}

	partitions, err := h.logPartitioner.ListPartitions()
	if err != nil {
		return 0, err
	}
	if len(partitions) == 0 {
		q := h.logDBConn().Table("log_records").Unscoped().Where("created_at < ?", cutoff)
		if keyID > 0 {
			q = q.Where("key_id = ?", keyID)
		}
		if modelName != "" {
			q = q.Where("model_name = ?", modelName)
		}
		res := q.Delete(&model.LogRecord{})
		return res.RowsAffected, res.Error
	}

	var deleted int64
	for _, part := range partitions {
		if !part.Start.Before(cutoff) {
			continue
		}
		q := h.logDBConn().Table(part.Table).Unscoped().Where("created_at < ?", cutoff)
		if keyID > 0 {
			q = q.Where("key_id = ?", keyID)
		}
		if modelName != "" {
			q = q.Where("model_name = ?", modelName)
		}
		res := q.Delete(&model.LogRecord{})
		if res.Error != nil {
			return deleted, res.Error
		}
		deleted += res.RowsAffected
	}
	return deleted, nil
}

// LogStats godoc
// @Summary      Log stats (admin)
// @Description  Aggregate log stats with basic filtering. Use group_by param for grouped statistics (model/day/month/hour/minute). Without group_by returns LogStatsResponse; with group_by returns GroupedStatsResponse. Note: minute-level aggregation is limited to 6-hour time ranges.
// @Tags         admin
// @Produce      json
// @Security     AdminAuth
// @Param        since    query     int     false  "unix seconds"
// @Param        until    query     int     false  "unix seconds"
// @Param        group_by query     string  false  "group by dimension: model, day, month, hour, minute. Returns GroupedStatsResponse when specified."  Enums(model, day, month, hour, minute)
// @Success      200  {object}  LogStatsResponse  "Default aggregated stats (when group_by is not specified)"
// @Success      200  {object}  GroupedStatsResponse  "Grouped stats (when group_by is specified)"
// @Failure      400  {object}  gin.H
// @Failure      500  {object}  gin.H
// @Router       /admin/logs/stats [get]
func (h *Handler) LogStats(c *gin.Context) {
	q := h.logBaseQuery()

	var sinceTime, untilTime *time.Time
	if t, ok := parseUnixSeconds(c.Query("since")); ok {
		q = q.Where("created_at >= ?", t)
		sinceTime = &t
	}
	if t, ok := parseUnixSeconds(c.Query("until")); ok {
		q = q.Where("created_at <= ?", t)
		untilTime = &t
	}

	groupBy := strings.TrimSpace(c.Query("group_by"))
	switch groupBy {
	case "model":
		h.logStatsByModel(c, q)
		return
	case "day":
		h.logStatsByDay(c, q)
		return
	case "month":
		h.logStatsByMonth(c, q)
		return
	case "hour":
		h.logStatsByHour(c, q)
		return
	case "minute":
		h.logStatsByMinute(c, q, sinceTime, untilTime)
		return
	}

	// Default: aggregated stats (backward compatible)
	var total int64
	if err := q.Count(&total).Error; err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"error": "failed to count logs", "details": err.Error()})
		return
	}

	type sums struct {
		TokensIn   int64
		TokensOut  int64
		AvgLatency float64
	}
	var s sums
	if err := q.Select("COALESCE(SUM(tokens_in),0) as tokens_in, COALESCE(SUM(tokens_out),0) as tokens_out, COALESCE(AVG(latency_ms),0) as avg_latency").Scan(&s).Error; err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"error": "failed to aggregate logs", "details": err.Error()})
		return
	}

	type bucket struct {
		StatusCode int
		Cnt        int64
	}
	var buckets []bucket
	if err := q.Select("status_code, COUNT(*) as cnt").Group("status_code").Scan(&buckets).Error; err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"error": "failed to bucket logs", "details": err.Error()})
		return
	}
	byStatus := make(map[string]int64, len(buckets))
	for _, b := range buckets {
		byStatus[strconv.Itoa(b.StatusCode)] = b.Cnt
	}

	c.JSON(http.StatusOK, LogStatsResponse{
		Total:      total,
		TokensIn:   s.TokensIn,
		TokensOut:  s.TokensOut,
		AvgLatency: s.AvgLatency,
		ByStatus:   byStatus,
	})
}

// logStatsByModel handles group_by=model
func (h *Handler) logStatsByModel(c *gin.Context, q *gorm.DB) {
	type modelStats struct {
		ModelName    string
		Cnt          int64
		TokensIn     int64
		TokensOut    int64
		AvgLatencyMs float64
	}
	var rows []modelStats
	if err := q.Select(`model_name, COUNT(*) as cnt, COALESCE(SUM(tokens_in),0) as tokens_in, COALESCE(SUM(tokens_out),0) as tokens_out, COALESCE(AVG(latency_ms),0) as avg_latency_ms`).
		Group("model_name").
		Order("cnt DESC").
		Scan(&rows).Error; err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"error": "failed to aggregate by model", "details": err.Error()})
		return
	}
	items := make([]GroupedStatsItem, 0, len(rows))
	for _, r := range rows {
		items = append(items, GroupedStatsItem{
			Model:        r.ModelName,
			Count:        r.Cnt,
			TokensIn:     r.TokensIn,
			TokensOut:    r.TokensOut,
			AvgLatencyMs: r.AvgLatencyMs,
		})
	}
	c.JSON(http.StatusOK, GroupedStatsResponse{Items: items})
}

// logStatsByDay handles group_by=day
func (h *Handler) logStatsByDay(c *gin.Context, q *gorm.DB) {
	type dayStats struct {
		Day       string
		Cnt       int64
		TokensIn  int64
		TokensOut int64
	}
	var rows []dayStats
	// PostgreSQL DATE function; SQLite uses date()
	if err := q.Select(`TO_CHAR(created_at, 'YYYY-MM-DD') as day, COUNT(*) as cnt, COALESCE(SUM(tokens_in),0) as tokens_in, COALESCE(SUM(tokens_out),0) as tokens_out`).
		Group("day").
		Order("day ASC").
		Scan(&rows).Error; err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"error": "failed to aggregate by day", "details": err.Error()})
		return
	}
	items := make([]GroupedStatsItem, 0, len(rows))
	for _, r := range rows {
		items = append(items, GroupedStatsItem{
			Date:      r.Day,
			Count:     r.Cnt,
			TokensIn:  r.TokensIn,
			TokensOut: r.TokensOut,
		})
	}
	c.JSON(http.StatusOK, GroupedStatsResponse{Items: items})
}

// logStatsByMonth handles group_by=month
func (h *Handler) logStatsByMonth(c *gin.Context, q *gorm.DB) {
	type monthStats struct {
		Month     string
		Cnt       int64
		TokensIn  int64
		TokensOut int64
	}
	var rows []monthStats
	// PostgreSQL format
	if err := q.Select(`TO_CHAR(created_at, 'YYYY-MM') as month, COUNT(*) as cnt, COALESCE(SUM(tokens_in),0) as tokens_in, COALESCE(SUM(tokens_out),0) as tokens_out`).
		Group("month").
		Order("month ASC").
		Scan(&rows).Error; err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"error": "failed to aggregate by month", "details": err.Error()})
		return
	}
	items := make([]GroupedStatsItem, 0, len(rows))
	for _, r := range rows {
		items = append(items, GroupedStatsItem{
			Month:     r.Month,
			Count:     r.Cnt,
			TokensIn:  r.TokensIn,
			TokensOut: r.TokensOut,
		})
	}
	c.JSON(http.StatusOK, GroupedStatsResponse{Items: items})
}

// logStatsByHour handles group_by=hour
func (h *Handler) logStatsByHour(c *gin.Context, q *gorm.DB) {
	type hourStats struct {
		Hour         string
		Cnt          int64
		TokensIn     int64
		TokensOut    int64
		AvgLatencyMs float64
	}
	var rows []hourStats
	// PostgreSQL DATE_TRUNC for hour-level aggregation
	if err := q.Select(`DATE_TRUNC('hour', created_at) as hour, COUNT(*) as cnt, COALESCE(SUM(tokens_in),0) as tokens_in, COALESCE(SUM(tokens_out),0) as tokens_out, COALESCE(AVG(latency_ms),0) as avg_latency_ms`).
		Group("hour").
		Order("hour ASC").
		Scan(&rows).Error; err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"error": "failed to aggregate by hour", "details": err.Error()})
		return
	}
	items := make([]GroupedStatsItem, 0, len(rows))
	for _, r := range rows {
		items = append(items, GroupedStatsItem{
			Hour:         r.Hour,
			Count:        r.Cnt,
			TokensIn:     r.TokensIn,
			TokensOut:    r.TokensOut,
			AvgLatencyMs: r.AvgLatencyMs,
		})
	}
	c.JSON(http.StatusOK, GroupedStatsResponse{Items: items})
}

// maxMinuteRangeDuration is the maximum time range allowed for minute-level aggregation (6 hours)
const maxMinuteRangeDuration = 6 * time.Hour

// logStatsByMinute handles group_by=minute with time range validation
func (h *Handler) logStatsByMinute(c *gin.Context, q *gorm.DB, sinceTime, untilTime *time.Time) {
	// Validate time range - minute-level aggregation requires since/until and max 6 hours
	if sinceTime == nil || untilTime == nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": "minute-level aggregation requires both 'since' and 'until' parameters"})
		return
	}

	duration := untilTime.Sub(*sinceTime)
	if duration > maxMinuteRangeDuration {
		c.JSON(http.StatusBadRequest, gin.H{
			"error":        "time range too large for minute-level aggregation",
			"max_hours":    6,
			"actual_hours": duration.Hours(),
		})
		return
	}

	if duration < 0 {
		c.JSON(http.StatusBadRequest, gin.H{"error": "'until' must be after 'since'"})
		return
	}

	type minuteStats struct {
		Minute       string
		Cnt          int64
		TokensIn     int64
		TokensOut    int64
		AvgLatencyMs float64
	}
	var rows []minuteStats
	// PostgreSQL DATE_TRUNC for minute-level aggregation
	if err := q.Select(`DATE_TRUNC('minute', created_at) as minute, COUNT(*) as cnt, COALESCE(SUM(tokens_in),0) as tokens_in, COALESCE(SUM(tokens_out),0) as tokens_out, COALESCE(AVG(latency_ms),0) as avg_latency_ms`).
		Group("minute").
		Order("minute ASC").
		Scan(&rows).Error; err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"error": "failed to aggregate by minute", "details": err.Error()})
		return
	}
	items := make([]GroupedStatsItem, 0, len(rows))
	for _, r := range rows {
		items = append(items, GroupedStatsItem{
			Minute:       r.Minute,
			Count:        r.Cnt,
			TokensIn:     r.TokensIn,
			TokensOut:    r.TokensOut,
			AvgLatencyMs: r.AvgLatencyMs,
		})
	}
	c.JSON(http.StatusOK, GroupedStatsResponse{Items: items})
}

// TrafficMetrics contains the metrics for a model in a bucket
type TrafficMetrics struct {
	Count     int64 `json:"count"`
	TokensIn  int64 `json:"tokens_in"`
	TokensOut int64 `json:"tokens_out"`
}

// ModelMetricsMap is a map from model name to TrafficMetrics.
// Keys are model names (e.g. "gpt-4", "claude-3-opus") or "other" for aggregated remaining models.
// Example: {"gpt-4": {"count": 10, "tokens_in": 1000, "tokens_out": 500}, "other": {"count": 3, "tokens_in": 200, "tokens_out": 100}}
type ModelMetricsMap map[string]TrafficMetrics

// TrafficBucket represents one time bucket with model breakdown
type TrafficBucket struct {
	Time      string `json:"time"`
	Timestamp int64  `json:"timestamp"`
	// Breakdown is a map from model name (e.g. "gpt-4", "claude-3-opus", "other") to its metrics
	Breakdown ModelMetricsMap `json:"breakdown"`
	Total     TrafficMetrics  `json:"total"`
}

// TrafficChartResponse is the response for traffic chart API
type TrafficChartResponse struct {
	Granularity string          `json:"granularity"`
	Since       int64           `json:"since"`
	Until       int64           `json:"until"`
	Models      []string        `json:"models"`
	Buckets     []TrafficBucket `json:"buckets"`
}

const (
	defaultTrafficTopN = 5
	maxTrafficTopN     = 20
)

// GetTrafficChart godoc
// @Summary      Traffic chart data (admin)
// @Description  Get time × model aggregated data for stacked traffic charts. Returns time buckets with per-model breakdown. The 'breakdown' field in each bucket is a map where keys are model names (e.g. "gpt-4", "claude-3-opus") and values are TrafficMetrics objects. Models outside top_n are aggregated under the key "other". Example: {"gpt-4": {"count": 10, "tokens_in": 1000, "tokens_out": 500}, "other": {"count": 3, "tokens_in": 200, "tokens_out": 100}}
// @Tags         admin
// @Produce      json
// @Security     AdminAuth
// @Param        granularity  query     string  false  "Time granularity: hour (default) or minute"  Enums(hour, minute)
// @Param        since        query     int     false  "Start time (unix seconds), defaults to 24h ago"
// @Param        until        query     int     false  "End time (unix seconds), defaults to now"
// @Param        top_n        query     int     false  "Number of top models to return (1-20), defaults to 5"
// @Success      200  {object}  TrafficChartResponse
// @Failure      400  {object}  gin.H
// @Failure      500  {object}  gin.H
// @Router       /admin/logs/stats/traffic-chart [get]
func (h *Handler) GetTrafficChart(c *gin.Context) {
	// Parse granularity
	granularity := strings.TrimSpace(c.Query("granularity"))
	if granularity == "" {
		granularity = "hour"
	}
	if granularity != "hour" && granularity != "minute" {
		c.JSON(http.StatusBadRequest, gin.H{"error": "granularity must be 'hour' or 'minute'"})
		return
	}

	// Parse time range
	now := time.Now().UTC()
	var sinceTime, untilTime time.Time

	if t, ok := parseUnixSeconds(c.Query("since")); ok {
		sinceTime = t
	} else {
		sinceTime = now.Add(-24 * time.Hour)
	}

	if t, ok := parseUnixSeconds(c.Query("until")); ok {
		untilTime = t
	} else {
		untilTime = now
	}

	// Validate time range for minute granularity
	if granularity == "minute" {
		if c.Query("since") == "" || c.Query("until") == "" {
			c.JSON(http.StatusBadRequest, gin.H{"error": "minute-level aggregation requires both 'since' and 'until' parameters"})
			return
		}
		duration := untilTime.Sub(sinceTime)
		if duration > maxMinuteRangeDuration {
			c.JSON(http.StatusBadRequest, gin.H{
				"error":        "time range too large for minute granularity",
				"max_hours":    6,
				"actual_hours": duration.Hours(),
			})
			return
		}
		if duration < 0 {
			c.JSON(http.StatusBadRequest, gin.H{"error": "'until' must be after 'since'"})
			return
		}
	}

	// Parse top_n
	topN := defaultTrafficTopN
	if raw := strings.TrimSpace(c.Query("top_n")); raw != "" {
		if v, err := strconv.Atoi(raw); err == nil && v > 0 {
			topN = v
		}
	}
	if topN > maxTrafficTopN {
		c.JSON(http.StatusBadRequest, gin.H{"error": "top_n cannot exceed 20"})
		return
	}

	// Build query
	q := h.logBaseQuery().
		Where("created_at >= ?", sinceTime).
		Where("created_at <= ?", untilTime)

	// Select with time truncation based on granularity
	var truncFunc string
	if granularity == "minute" {
		truncFunc = "DATE_TRUNC('minute', created_at)"
	} else {
		truncFunc = "DATE_TRUNC('hour', created_at)"
	}

	type bucketModelStats struct {
		Bucket    time.Time
		ModelName string
		Cnt       int64
		TokensIn  int64
		TokensOut int64
	}
	var rows []bucketModelStats

	if err := q.Select(truncFunc + " as bucket, model_name, COUNT(*) as cnt, COALESCE(SUM(tokens_in),0) as tokens_in, COALESCE(SUM(tokens_out),0) as tokens_out").
		Group("bucket, model_name").
		Order("bucket ASC, cnt DESC").
		Scan(&rows).Error; err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"error": "failed to aggregate traffic data", "details": err.Error()})
		return
	}

	// Calculate global model counts for top_n selection
	modelCounts := make(map[string]int64)
	for _, r := range rows {
		modelCounts[r.ModelName] += r.Cnt
	}

	// Get top N models
	type modelCount struct {
		name  string
		count int64
	}
	var modelList []modelCount
	for name, cnt := range modelCounts {
		modelList = append(modelList, modelCount{name, cnt})
	}
	// Sort by count descending
	for i := 0; i < len(modelList)-1; i++ {
		for j := i + 1; j < len(modelList); j++ {
			if modelList[j].count > modelList[i].count {
				modelList[i], modelList[j] = modelList[j], modelList[i]
			}
		}
	}

	topModels := make(map[string]bool)
	var modelNames []string
	for i := 0; i < len(modelList) && i < topN; i++ {
		topModels[modelList[i].name] = true
		modelNames = append(modelNames, modelList[i].name)
	}
	hasOther := len(modelList) > topN
	if hasOther {
		modelNames = append(modelNames, "other")
	}

	// Build buckets with breakdown
	bucketMap := make(map[int64]*TrafficBucket)
	var bucketOrder []int64

	for _, r := range rows {
		ts := r.Bucket.Unix()
		bucket, exists := bucketMap[ts]
		if !exists {
			bucket = &TrafficBucket{
				Time:      r.Bucket.UTC().Format(time.RFC3339),
				Timestamp: ts,
				Breakdown: make(map[string]TrafficMetrics),
			}
			bucketMap[ts] = bucket
			bucketOrder = append(bucketOrder, ts)
		}

		modelKey := r.ModelName
		if !topModels[modelKey] {
			modelKey = "other"
		}

		existing := bucket.Breakdown[modelKey]
		bucket.Breakdown[modelKey] = TrafficMetrics{
			Count:     existing.Count + r.Cnt,
			TokensIn:  existing.TokensIn + r.TokensIn,
			TokensOut: existing.TokensOut + r.TokensOut,
		}

		bucket.Total.Count += r.Cnt
		bucket.Total.TokensIn += r.TokensIn
		bucket.Total.TokensOut += r.TokensOut
	}

	// Build response buckets in order
	buckets := make([]TrafficBucket, 0, len(bucketOrder))
	for _, ts := range bucketOrder {
		buckets = append(buckets, *bucketMap[ts])
	}

	c.JSON(http.StatusOK, TrafficChartResponse{
		Granularity: granularity,
		Since:       sinceTime.Unix(),
		Until:       untilTime.Unix(),
		Models:      modelNames,
		Buckets:     buckets,
	})
}

// ListSelfLogs godoc
// @Summary      List logs (master)
// @Description  List request logs for the authenticated master
// @Tags         master
// @Produce      json
// @Security     MasterAuth
// @Param        limit        query     int     false  "limit (default 50, max 200)"
// @Param        offset       query     int     false  "offset"
// @Param        since        query     int     false  "unix seconds"
// @Param        until        query     int     false  "unix seconds"
// @Param        model        query     string  false  "model"
// @Param        status_code  query     int     false  "status code"
// @Success      200  {object}  ListMasterLogsResponse
// @Failure      401  {object}  gin.H
// @Failure      500  {object}  gin.H
// @Router       /v1/logs [get]
func (h *MasterHandler) ListSelfLogs(c *gin.Context) {
	master, exists := c.Get("master")
	if !exists {
		c.JSON(http.StatusUnauthorized, gin.H{"error": "master key not found in context"})
		return
	}
	m := master.(*model.Master)
	limit, offset := parseLimitOffset(c)

	q, err := h.masterLogBase(m.ID)
	if err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"error": "failed to build log query", "details": err.Error()})
		return
	}

	if t, ok := parseUnixSeconds(c.Query("since")); ok {
		q = q.Where("log_records.created_at >= ?", t)
	}
	if t, ok := parseUnixSeconds(c.Query("until")); ok {
		q = q.Where("log_records.created_at <= ?", t)
	}
	if raw := strings.TrimSpace(c.Query("model")); raw != "" {
		q = q.Where("log_records.model_name = ?", raw)
	}
	if raw := strings.TrimSpace(c.Query("status_code")); raw != "" {
		if v, err := strconv.Atoi(raw); err == nil && v > 0 {
			q = q.Where("log_records.status_code = ?", v)
		}
	}

	var total int64
	if err := q.Count(&total).Error; err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"error": "failed to count logs", "details": err.Error()})
		return
	}
	var rows []model.LogRecord
	if err := q.Order("log_records.id desc").Limit(limit).Offset(offset).Find(&rows).Error; err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"error": "failed to list logs", "details": err.Error()})
		return
	}
	out := make([]MasterLogView, 0, len(rows))
	for _, r := range rows {
		out = append(out, toMasterLogView(r))
	}
	c.JSON(http.StatusOK, ListMasterLogsResponse{Total: total, Limit: limit, Offset: offset, Items: out})
}

// GetSelfLogStats godoc
// @Summary      Log stats (master)
// @Description  Aggregate request log stats for the authenticated master
// @Tags         master
// @Produce      json
// @Security     MasterAuth
// @Param        since   query     int     false  "unix seconds"
// @Param        until   query     int     false  "unix seconds"
// @Success      200  {object}  LogStatsResponse
// @Failure      401  {object}  gin.H
// @Failure      500  {object}  gin.H
// @Router       /v1/logs/stats [get]
func (h *MasterHandler) GetSelfLogStats(c *gin.Context) {
	master, exists := c.Get("master")
	if !exists {
		c.JSON(http.StatusUnauthorized, gin.H{"error": "master key not found in context"})
		return
	}
	m := master.(*model.Master)

	q, err := h.masterLogBase(m.ID)
	if err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"error": "failed to build log query", "details": err.Error()})
		return
	}

	if t, ok := parseUnixSeconds(c.Query("since")); ok {
		q = q.Where("log_records.created_at >= ?", t)
	}
	if t, ok := parseUnixSeconds(c.Query("until")); ok {
		q = q.Where("log_records.created_at <= ?", t)
	}

	var total int64
	if err := q.Count(&total).Error; err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"error": "failed to count logs", "details": err.Error()})
		return
	}

	type sums struct {
		TokensIn   int64
		TokensOut  int64
		AvgLatency float64
	}
	var s sums
	if err := q.Select("COALESCE(SUM(log_records.tokens_in),0) as tokens_in, COALESCE(SUM(log_records.tokens_out),0) as tokens_out, COALESCE(AVG(log_records.latency_ms),0) as avg_latency").Scan(&s).Error; err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"error": "failed to aggregate logs", "details": err.Error()})
		return
	}

	type bucket struct {
		StatusCode int
		Cnt        int64
	}
	var buckets []bucket
	if err := q.Select("log_records.status_code as status_code, COUNT(*) as cnt").Group("log_records.status_code").Scan(&buckets).Error; err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"error": "failed to bucket logs", "details": err.Error()})
		return
	}
	byStatus := make(map[string]int64, len(buckets))
	for _, b := range buckets {
		byStatus[strconv.Itoa(b.StatusCode)] = b.Cnt
	}

	c.JSON(http.StatusOK, LogStatsResponse{
		Total:      total,
		TokensIn:   s.TokensIn,
		TokensOut:  s.TokensOut,
		AvgLatency: s.AvgLatency,
		ByStatus:   byStatus,
	})
}