//! Session log record types. One JSON object per line; assistant messages are stored verbatim.

use serde::{Deserialize, Serialize};

use crate::{CallId, DataClass, Epoch, Hash32, SessionId, Timestamp};

#[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
#[serde(deny_unknown_fields)]
pub struct ToolCall {
    pub id: String,
    pub name: String,
    pub arguments: String,
}

/// What one completion cost. The same five numbers as `LogRecord::Usage`, without the time.
#[derive(Debug, Clone, Copy, PartialEq, Eq, Serialize, Deserialize)]
#[serde(deny_unknown_fields)]
pub struct Usage {
    pub cache_n: u64,
    pub prompt_n: u64,
    pub predicted_n: u64,
    pub reasoning_tokens: u64,
    pub thinking_capped: bool,
}

// JSON: {"type":"user","time":"…","content":"…"} ; the tag sits beside the fields; types are snake_case
#[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
#[serde(tag = "type", rename_all = "snake_case", deny_unknown_fields)]
pub enum LogRecord {
    SessionStart {
        time: Timestamp,
        session: SessionId,
        epoch: Epoch,
        slot: u32,
        baseline: Hash32,
    },
    User {
        time: Timestamp,
        content: String,
    },
    Assistant {
        time: Timestamp,
        content: Option<String>,
        reasoning_content: Option<String>,
        tool_calls: Vec<ToolCall>,
    },
    ToolResult {
        time: Timestamp,
        call: CallId,
        tool_call_id: String,
        content: String,
        class: DataClass,
        untrusted: bool,
        truncated: bool,
    },
    Usage {
        time: Timestamp,
        cache_n: u64,
        prompt_n: u64,
        predicted_n: u64,
        reasoning_tokens: u64,
        thinking_capped: bool,
    },
    CacheLoss {
        time: Timestamp,
        expected: u64,
        got: u64,
    },
    EpochEnd {
        time: Timestamp,
        next: Epoch,
        summary: String,
    },
}