common

type AssistantMessage struct {
	Model        string         `json:"model"`
	ID           string         `json:"id"`
	Type         string         `json:"type"`
	Role         string         `json:"role"`
	Content      []ContentBlock `json:"content"`
	StopReason   *string        `json:"stop_reason,omitempty"`
	StopSequence *string        `json:"stop_sequence,omitempty"`
	Usage        *UsageInfo     `json:"usage,omitempty"`
}

type AssistantMessageEvent struct {
	Message AssistantMessage `json:"message"`
}

type ContentBlock struct {
	Type     string `json:"type"`
	Text     string `json:"text,omitempty"`
	ID       string `json:"id,omitempty"`
	Name     string `json:"name,omitempty"`
	Input    string `json:"input,omitempty"`
	Thinking string `json:"thinking,omitempty"`
}

type ErrInvalidPath struct {
	Path string
	Err  error
}

type ErrInvalidSessionFormat struct {
	File string
	Err  error
}

type ErrProjectNotFound struct {
	ProjectPath string
}

type ErrSessionNotFound struct {
	SessionID string
}

type EventData interface {
	EventType() string
}

type FileHistorySnapshotEvent struct {
	MessageID string `json:"messageId"`
	Snapshot  struct {
		MessageID          string                 `json:"messageId"`
		TrackedFileBackups map[string]interface{} `json:"trackedFileBackups"`
		Timestamp          string                 `json:"timestamp"`
	} `json:"snapshot"`
	IsSnapshotUpdate bool `json:"isSnapshotUpdate"`
}

type ResultEvent struct {
	Subtype       string    `json:"subtype"`
	Result        string    `json:"result"`
	TotalCostUSD  float64   `json:"total_cost_usd"`
	DurationMS    int       `json:"duration_ms"`
	DurationAPIMS int       `json:"duration_api_ms,omitempty"`
	NumTurns      int       `json:"num_turns"`
	Usage         UsageInfo `json:"usage"`
	Error         string    `json:"error,omitempty"`
}

type SessionEvent struct {
	Type      string    `json:"type"`
	Subtype   string    `json:"subtype,omitempty"`
	Timestamp time.Time `json:"timestamp"`
	Data      EventData `json:"data"`
}

type SessionMetadata struct {
	SessionID   string        `json:"session_id"`
	ProjectPath string        `json:"project_path"`
	Status      SessionStatus `json:"status"`

	// Time information
	StartTime  time.Time `json:"start_time"`
	EndTime    time.Time `json:"end_time,omitempty"`
	DurationMS int64     `json:"duration_ms,omitempty"`

	// Session summary
	FirstMessage         string `json:"first_message,omitempty"`          // User's first prompt
	LastUserMessage      string `json:"last_user_message,omitempty"`      // Last user message (for context)
	LastAssistantMessage string `json:"last_assistant_message,omitempty"` // Last assistant response
	LastResult           string `json:"last_result,omitempty"`            // Final result/error message
	NumTurns             int    `json:"num_turns,omitempty"`              // Number of exchanges

	// Usage metrics
	InputTokens     int     `json:"input_tokens,omitempty"`
	OutputTokens    int     `json:"output_tokens,omitempty"`
	CacheReadTokens int     `json:"cache_read_tokens,omitempty"`
	TotalCostUSD    float64 `json:"total_cost_usd,omitempty"`

	// Error (if failed)
	Error string `json:"error,omitempty"`
}

type SessionStatus string

type SessionStore interface {
	// ListSessions returns all sessions for a project, ordered by start time (newest first)
	ListSessions(ctx context.Context, projectPath string) ([]SessionMetadata, error)

	// GetSession retrieves a specific session's metadata
	GetSession(ctx context.Context, sessionID string) (*SessionMetadata, error)

	// GetRecentSessions returns the N most recent sessions
	GetRecentSessions(ctx context.Context, projectPath string, limit int) ([]SessionMetadata, error)

	// GetSessionEvents retrieves events from a session
	// offset: number of events to skip
	// limit: maximum number of events to return (0 = all)
	GetSessionEvents(ctx context.Context, sessionID string, offset, limit int) ([]SessionEvent, error)

	// GetSessionSummary returns a summary (first N and last M events)
	GetSessionSummary(ctx context.Context, sessionID string, firstN, lastM int) (*SessionSummary, error)
}

type SessionSummary struct {
	Metadata SessionMetadata `json:"metadata"`
	Head     []SessionEvent  `json:"head"` // First N events
	Tail     []SessionEvent  `json:"tail"` // Last M events
}

type SystemEvent struct {
	Subtype    string `json:"subtype"`
	DurationMS int    `json:"durationMs,omitempty"`
	UUID       string `json:"uuid,omitempty"`
	IsMeta     bool   `json:"isMeta,omitempty"`
}

type SystemInitEvent struct {
	SessionID string `json:"session_id"`
	Timestamp string `json:"timestamp"`
}

type ToolResultEvent struct {
	ToolUseID string `json:"tool_use_id"`
	Content   string `json:"content,omitempty"`
	IsError   bool   `json:"is_error,omitempty"`
	Output    string `json:"output,omitempty"`
}

type ToolUseEvent struct {
	Name      string `json:"name"`
	Input     string `json:"input"`
	ToolUseID string `json:"tool_use_id"`
}

type UsageInfo struct {
	InputTokens              int `json:"input_tokens"`
	OutputTokens             int `json:"output_tokens"`
	CacheCreationInputTokens int `json:"cache_creation_input_tokens,omitempty"`
	CacheReadInputTokens     int `json:"cache_read_input_tokens,omitempty"`
}

type UserMessageEvent struct {
	ParentUUID  *string `json:"parentUuid"`
	IsSidechain bool    `json:"isSidechain"`
	UserType    string  `json:"userType"`
	CWD         string  `json:"cwd"`
	SessionID   string  `json:"sessionId"`
	Version     string  `json:"version"`
	GitBranch   string  `json:"gitBranch"`
	Type        string  `json:"type"`
	Message     struct {
		Role    string `json:"role"`
		Content string `json:"content"`
	} `json:"message"`
	UUID      string `json:"uuid"`
	Timestamp string `json:"timestamp"`
}