roi

type Arm struct {
	Name string `json:"name"`
	// Weight is the configured share (randomized only).
	Weight float64 `json:"weight,omitempty"`
	// Developers on the roster assigned to the arm; Active opened >= 1 PR.
	Developers int `json:"developers"`
	Active     int `json:"active"`
	PRs        int `json:"prs"`
	Merged     int `json:"merged"`
	// AI spend over the window and the arm-level cost per merged PR, when a
	// cost source has rows for the arm. Spend and PRs are joined per arm,
	// not per developer, so there is no CI on CostPerMergedPR.
	SpendUSD        float64 `json:"spendUSD,omitempty"`
	CostUnits       int     `json:"costUnits,omitempty"`
	CostPerMergedPR float64 `json:"costPerMergedPR,omitempty"`
}

type ArmCost struct {
	USD   float64 `json:"usd"`
	Units int     `json:"units"`
}

type ClickHouseStore struct{ CH *promote.ClickHouse }

type CostSource interface {
	ArmCosts(ctx context.Context, experiment string, rings []string, from, to time.Time) (map[string]ArmCost, string, error)
}

type Effect struct {
	Metric string `json:"metric"`
	Arm    string `json:"arm"` // the treatment arm compared with the control
	// Kind is "causal" (randomized) or "association" (observational).
	Kind   string `json:"kind"`
	Better string `json:"better,omitempty"` // decrease | increase; "" = descriptive
	State  string `json:"state"`
	// Outcome is improved | worsened for a significant effect with a direction.
	Outcome string `json:"outcome,omitempty"`
	stats.DiffResult
	// MDERel is the relative effect detectable with 80% power at Alpha.
	MDERel  float64  `json:"mdeRel,omitempty"`
	Slices  []Effect `json:"slices,omitempty"`
	Novelty bool     `json:"novelty,omitempty"`
	From    string   `json:"from,omitempty"` // set on slices
}

type FileStore struct{ Path string }

type GitHub struct {
	URL   string // GraphQL endpoint; default GitHubGraphQL
	Token string
	// HotfixLabel marks a hotfix PR; a merged one marks every PR it
	// references (#N) as a change failure. Default "hotfix".
	HotfixLabel string
	Client      *http.Client // default: 60s timeout, no redirects
}

type Identities struct {
	// contains filtered or unexported fields
}

type Options struct {
	Org *policy.Org
	// Experiment (randomized) or Rings (observational; the first is the
	// baseline); exactly one.
	Experiment *policy.Experiment
	Rings      []string
	From, To   time.Time
	// Slices splits the window for the novelty check (default 3; < 2 off).
	Slices int
	// MDE is the relative effect the study must be able to detect for a null
	// result to count as "no detectable effect" (default 0.10).
	MDE float64
	// Alpha for CIs (default 0.05); SRMAlpha for the SRM test (default 0.001).
	Alpha, SRMAlpha float64
	// MinDevelopers per arm before an effect is estimated (default 10).
	MinDevelopers int
	Iters         int    // bootstrap resamples (default 2000)
	Seed          uint64 // bootstrap seed (default 1)
}

type PR struct {
	Source string `json:"source"` // github | file
	Repo   string `json:"repo"`
	Number int64  `json:"number"`
	// Author is the SCM login, lowercased. Subject, when the source knows it
	// (a generic export), is the Halos subject id and wins over Author.
	Author  string `json:"author,omitempty"`
	Subject string `json:"subject,omitempty"`
	// Bot marks an author the SCM reports as a bot account; never counted.
	Bot          bool       `json:"bot,omitempty"`
	OpenedAt     time.Time  `json:"opened_at"`
	MergedAt     *time.Time `json:"merged_at,omitempty"`
	ReviewRounds int        `json:"review_rounds"`
	Additions    int        `json:"additions"`
	Deletions    int        `json:"deletions"`
	// ChangeFailure is the change-failure proxy: the merged PR was later
	// reverted or followed by a hotfix that references it.
	ChangeFailure bool `json:"change_failure,omitempty"`
}

type Report struct {
	Design     string           `json:"design"`
	Claim      string           `json:"claim"`
	Status     string           `json:"status"`
	Experiment string           `json:"experiment,omitempty"`
	Rings      []string         `json:"rings,omitempty"`
	From       time.Time        `json:"from"`
	To         time.Time        `json:"to"`
	Control    string           `json:"control"`
	Arms       []Arm            `json:"arms"`
	SRM        *stats.SRMResult `json:"srm,omitempty"`
	Effects    []Effect         `json:"effects"`
	CostSource string           `json:"costSource,omitempty"`
	// Excluded counts PRs left out, by reason.
	Excluded       map[string]int `json:"excluded"`
	UnmappedLogins []string       `json:"unmappedLogins,omitempty"` // first 20
	Warnings       []string       `json:"warnings"`
}

type Store interface {
	Put(ctx context.Context, prs []PR) error
	// PRs returns the PRs opened in [from, to).
	PRs(ctx context.Context, from, to time.Time) ([]PR, error)
}