compaction

type BranchPreparation struct {
	// Messages extracted for summarization, in chronological order.
	Messages []agent.AgentMessage
	// FileOps extracted from tool calls and prior branch_summary details.
	FileOps FileOperations
	// TotalTokens is the estimated token count of Messages.
	TotalTokens int
}

type BranchSummaryDetails struct {
	ReadFiles     []string `json:"readFiles"`
	ModifiedFiles []string `json:"modifiedFiles"`
}

type BranchSummaryResult struct {
	Summary       string
	ReadFiles     []string
	ModifiedFiles []string
	Aborted       bool
	Error         string
	// Usage is the summarization LLM call usage, if reported.
	Usage *ai.Usage
}

type BranchSummarySettings struct {
	ReserveTokens int
}

type CollectEntriesResult struct {
	// Entries to summarize, in chronological order.
	Entries []codingagent.SessionEntry
	// CommonAncestorID is the deepest node on both the old and target paths,
	// or "" if none found.
	CommonAncestorID string
}

type CompactionDetails struct {
	ReadFiles     []string `json:"readFiles"`
	ModifiedFiles []string `json:"modifiedFiles"`
}

type CompactionPreparation struct {
	FirstKeptEntryID    string               `json:"firstKeptEntryId"`
	MessagesToSummarize []agent.AgentMessage `json:"messagesToSummarize"`
	TurnPrefixMessages  []agent.AgentMessage `json:"turnPrefixMessages"`
	IsSplitTurn         bool                 `json:"isSplitTurn"`
	TokensBefore        int                  `json:"tokensBefore"`
	PreviousSummary     string               `json:"previousSummary,omitempty"`
	FileOps             FileOperations       `json:"fileOps"`
	Settings            CompactionSettings   `json:"settings"`
}

type CompactionResult struct {
	Summary          string
	FirstKeptEntryID string
	TokensBefore     int
	Details          CompactionDetails
	// Usage is the combined usage of the summarization LLM call(s), if the
	// completer reported it. Mirrors upstream CompactionResult.usage.
	Usage *ai.Usage
}

type CompactionSettings struct {
	Enabled          bool `json:"enabled"`
	ReserveTokens    int  `json:"reserveTokens"`    // tokens reserved for response; default 16384
	KeepRecentTokens int  `json:"keepRecentTokens"` // tokens to keep from recent history; default 20000
}

type CutPointResult struct {
	// FirstKeptEntryIndex is the index in entries[] of the first entry to keep.
	FirstKeptEntryIndex int
	// TurnStartIndex is the index of the user/bash message starting the split
	// turn, or -1 if not splitting.
	TurnStartIndex int
	// IsSplitTurn is true when the cut lands in the middle of a turn.
	IsSplitTurn bool
}

type FileOperations struct {
	Read    map[string]struct{}
	Written map[string]struct{}
	Edited  map[string]struct{}
}

type GenerateBranchSummaryOptions struct {
	// Model to use for summarization.
	Model *ai.Model
	// Completer handles the actual LLM call.
	Completer SimpleCompleter
	// StreamFn overrides Completer when supplied, as in compaction.
	StreamFn StreamFn
	// CustomInstructions are appended to (or replace) the default prompt.
	CustomInstructions string
	// ReplaceInstructions, when true, replaces the default prompt entirely.
	ReplaceInstructions bool
	// ReserveTokens are subtracted from the model context window for the
	// prompt + response budget. Default 16384.
	ReserveTokens int
	// Retry, when non-nil, retries transient summarization errors with bounded
	// exponential backoff. Mirrors upstream branch-summarization retry wiring.
	Retry *RetryOptions
}

type GenerateBugReportSummaryOptions struct {
	Messages  []agent.AgentMessage
	Hint      string
	Model     *ai.Model
	Completer SimpleCompleter
	StreamFn  StreamFn
	Retry     *RetryOptions
	// ThinkingLevel applies to reasoning-capable models.
	ThinkingLevel ai.ThinkingLevel
	// SessionID is the routing session ID forwarded without prompt caching.
	SessionID string
}

type ReadonlySession interface {
	// Branch returns the root-first path ending at leafID.
	// Returns nil if leafID is not found.
	Branch(leafID string) []codingagent.SessionEntry
	// EntryByID looks up a single entry by ID.
	// Returns (zero, false) if not found.
	EntryByID(id string) (codingagent.SessionEntry, bool)
}

type RetryCallbacks struct {
	// OnRetryScheduled fires before the backoff sleep of each retry (1-indexed).
	OnRetryScheduled func(attempt, maxAttempts, delayMs int, errMsg string)
	// OnRetryAttemptStart fires after the backoff sleep, before the retried call.
	OnRetryAttemptStart func()
	// OnRetryFinished fires once when a retried loop ends.
	OnRetryFinished func()
}

type RetryOptions struct {
	Policy      RetryPolicy
	IsRetryable func(errMsg string) bool
	Callbacks   RetryCallbacks
}

type RetryPolicy struct {
	Enabled bool
	// MaxRetries is the max retry attempts (0 = no retries). The initial call
	// never counts as a retry.
	MaxRetries int
	// BaseDelayMs is the base backoff; per-attempt delay is
	// BaseDelayMs * 2^(attempt-1).
	BaseDelayMs int
	// MaxAgentDelayMs caps each delay; nil uses ai.DefaultMaxAgentRetryDelayMs.
	MaxAgentDelayMs *int
}

type SimpleCompleter interface {
	CompleteSimple(ctx context.Context, model *ai.Model, systemPrompt string, messages []agent.AgentMessage, options ai.StreamOptions) (string, *ai.Usage, error)
}

type StreamFn func(ctx context.Context, model *ai.Model, systemPrompt string, messages []agent.AgentMessage, options ai.StreamOptions) (string, *ai.Usage, error)