namespace ClawdDotNet.Core.Transcripts;

/// <summary>What a transcript entry is.</summary>
public static class TranscriptEntryKind
{
    /// <summary>The task or message the run started with.</summary>
    public const string User = "user";

    /// <summary>A follow-up the engine itself sent (empty answer, missing result line).</summary>
    public const string EngineNote = "engine";

    /// <summary>One model response: text and/or tool calls, with the tokens of this step.</summary>
    public const string Assistant = "assistant";

    /// <summary>The result of one tool call.</summary>
    public const string ToolResult = "tool_result";

    /// <summary>Something that happened to the context, e.g. compaction.</summary>
    public const string Event = "event";
}

/// <summary>One tool call as the model issued it.</summary>
public sealed record TranscriptToolCall(string Id, string Name, string Arguments);

/// <summary>
/// One entry of a run transcript. Texts are stored as the model saw or wrote them, after
/// secret scrubbing and clipping (<see cref="Clipped"/>).
/// </summary>
public sealed record TranscriptEntry
{
    public string Kind { get; init; } = "";
    public DateTime At { get; init; }
    public string? Text { get; init; }
    public IReadOnlyList<TranscriptToolCall>? ToolCalls { get; init; }

    /// <summary>For <see cref="TranscriptEntryKind.ToolResult"/>: which call and tool.</summary>
    public string? ToolCallId { get; init; }
    public string? ToolName { get; init; }

    /// <summary>For <see cref="TranscriptEntryKind.Assistant"/>: usage of this single step.</summary>
    public int? PromptTokens { get; init; }
    public int? CompletionTokens { get; init; }
    public int? CachedTokens { get; init; }
    public decimal? CostUsd { get; init; }
    public string? FinishReason { get; init; }

    /// <summary>The text was shortened to stay within the limits.</summary>
    public bool Clipped { get; init; }
}

/// <summary>
/// Prompt and response of one run (#660), joined to receipts and audit via
/// <see cref="RunId"/>. The system prompt is stored once per distinct text and referenced
/// by <see cref="SystemPromptHash"/>.
/// </summary>
public sealed record RunTranscript
{
    public string RunId { get; init; } = "";
    public string AgentId { get; init; } = "";
    public string Model { get; init; } = "";
    public string Source { get; init; } = "";
    public string? TaskId { get; init; }
    public DateTime StartedAt { get; init; }
    public DateTime? CompletedAt { get; init; }
    public string Status { get; init; } = "";
    public string? SystemPromptHash { get; init; }

    /// <summary>The task or message as written, for lists. Falls back to the first user entry.</summary>
    public string? PromptPreview { get; init; }

    public IReadOnlyList<TranscriptEntry> Entries { get; init; } = [];

    /// <summary>Characters stored, after clipping.</summary>
    public int SizeChars { get; init; }

    /// <summary>The run exceeded the size limit; later entries are shortened or omitted.</summary>
    public bool Truncated { get; init; }
}

/// <summary>A transcript without its entries — for lists.</summary>
public sealed record RunTranscriptSummary(
    string RunId,
    string AgentId,
    string Model,
    string Source,
    string? TaskId,
    DateTime StartedAt,
    DateTime? CompletedAt,
    string Status,
    string Prompt,
    string Response,
    int SizeChars,
    bool Truncated);

/// <summary>Filter for <see cref="IRunTranscriptStore.ListAsync"/>.</summary>
public sealed record TranscriptQuery
{
    public string? AgentId { get; init; }
    public DateTime? From { get; init; }
    public DateTime? To { get; init; }

    /// <summary>Full text over the whole transcript.</summary>
    public string? Search { get; init; }

    public int Limit { get; init; } = 50;
    public int Offset { get; init; }
}