//! `public.zig` — the sole exported root of `libpanto`.
//!
//! This file is the **explicit public API allowlist**. Internal modules keep
//! their `pub` declarations (needed for cross-file linking) but are never
//! re-exported here; the public surface is what this file names, not
//! "whatever happens to be `pub`."
//!
//! The surface is organized around two user jobs (see
//! `docs/libpanto-cleanup.md`):
//!   1. Run an agent loop — configure a provider, register tools, submit a
//!      turn, consume the pull event stream, persist.
//!   2. Construct & operate on conversations — build a `Conversation` by
//!      hand, do context-management surgery.
//!
//! Three façade buckets:
//!   - **behavioral** (`Agent`, `Stream`, `Conversation`): wrap a pointer to
//!     a heap-pinned internal, exposing only the chosen methods.
//!   - **data (read/output)** (`Event`, `Usage`, `Pricing`, `SessionInfo`):
//!     aliased straight through; inspected field-by-field.
//!   - **data (constructed)** (`ContentBlock`, `Message`, the block types,
//!     the `Config` family): aliased straight through; Zig users build them
//!     with `ArrayList` directly.

const std = @import("std");

const config_mod = @import("config.zig");
const conversation_mod = @import("conversation.zig");
const agent_mod = @import("agent.zig");
const stream_mod = @import("stream.zig");
const provider_mod = @import("provider.zig");
const tool_mod = @import("tool.zig");
const tool_source_mod = @import("tool_source.zig");
const pricing_mod = @import("pricing.zig");
const session_store_mod = @import("session_store.zig");
const fs_store_mod = @import("file_system_jsonl_store.zig");
const null_store_mod = @import("null_store.zig");

// ===========================================================================
// Process lifecycle
// ===========================================================================

/// Initialize the process-global HTTP client. Call once before any turn.
pub fn init(allocator: std.mem.Allocator, io: std.Io) void {
    config_mod.initHttp(allocator, io);
}

/// Tear down the process-global HTTP client. Call once at shutdown.
pub fn deinit() void {
    config_mod.deinitHttp();
}

// ===========================================================================
// Config (data, aliased)
// ===========================================================================

pub const Config = config_mod.Config;
pub const ProviderConfig = config_mod.ProviderConfig;
pub const OpenAIChatConfig = config_mod.OpenAIChatConfig;
pub const AnthropicMessagesConfig = config_mod.AnthropicMessagesConfig;
pub const APIStyle = config_mod.APIStyle;
pub const ReasoningEffort = config_mod.ReasoningEffort;
pub const CompactionConfig = config_mod.CompactionConfig;
pub const RetryConfig = config_mod.RetryConfig;
pub const WireIdentity = config_mod.WireIdentity;

// ===========================================================================
// Conversation construction (data, aliased)
// ===========================================================================

pub const ContentBlock = conversation_mod.ContentBlock;
pub const Message = conversation_mod.Message;
pub const MessageRole = conversation_mod.MessageRole;
pub const TextualBlock = conversation_mod.TextualBlock;
pub const ThinkingBlock = conversation_mod.ThinkingBlock;
pub const ToolUseBlock = conversation_mod.ToolUseBlock;
pub const ToolResultBlock = conversation_mod.ToolResultBlock;
pub const ResultPartStored = conversation_mod.ResultPartStored;
pub const StoredMediaPart = conversation_mod.StoredMediaPart;
pub const SystemBlock = conversation_mod.SystemBlock;
pub const SystemMode = conversation_mod.SystemMode;
pub const CompactionSummaryBlock = conversation_mod.CompactionSummaryBlock;
pub const Usage = conversation_mod.Usage;
pub const effectiveSystemBlocks = conversation_mod.effectiveSystemBlocks;

/// The conversation type. Aliased straight through: its interface has been
/// pared down to exactly the public surface (constructors `init`/`deinit`,
/// the `add*`/`replace*` builders, and the `messages`/`allocator` data
/// fields), so no façade is needed. This is what `Session.load` returns,
/// what `Agent.init` adopts, and what `Agent.conversation()` borrows a
/// pointer to (for in-place surgery). Build one standalone with `init` for
/// by-hand construction; once handed to an `Agent` it is owned by the agent.
pub const Conversation = conversation_mod.Conversation;

// ===========================================================================
// Tools (data + small façade)
// ===========================================================================

pub const Tool = tool_mod.Tool;
pub const ToolSource = tool_source_mod.ToolSource;
pub const ToolDecl = tool_mod.ToolDecl;
pub const ToolCall = tool_source_mod.Call;
pub const ToolCallResult = tool_source_mod.CallResult;
pub const MediaPart = tool_mod.MediaPart;
pub const ResultPart = tool_mod.ResultPart;

/// Result-part ergonomics: a thin struct wrapper around `[]ResultPart`
/// (a bare alias can't carry methods).
pub const ResultParts = struct {
    items: []ResultPart,

    pub fn fromText(alloc: std.mem.Allocator, text: []const u8) !ResultParts {
        return .{ .items = try tool_mod.textResult(alloc, text) };
    }
    pub fn fromTextOwned(alloc: std.mem.Allocator, text: []u8) !ResultParts {
        return .{ .items = try tool_mod.ownedTextResult(alloc, text) };
    }
    pub fn deinit(self: ResultParts, alloc: std.mem.Allocator) void {
        tool_mod.freeResultParts(alloc, self.items);
    }
};

// ===========================================================================
// Stream (behavioral, pointer-wrapped)
// ===========================================================================

pub const Event = stream_mod.Event;
pub const ContentBlockType = provider_mod.ContentBlockType;
pub const ProviderRetryInfo = provider_mod.ProviderRetryInfo;

/// The transparent turn state machine, renamed from the internal `Phase`.
pub const State = agent_mod.Stream.Phase;

pub const Stream = struct {
    inner: *agent_mod.Stream,

    /// `!?Event`: a value is progress (including the terminal event), `null`
    /// is exhaustion, an error is a genuine failure.
    pub fn next(self: Stream) !?Event {
        return self.inner.next();
    }
    pub fn deinit(self: Stream) void {
        // The internal `Stream.deinit` persists the turn tail and frees its
        // own heap allocation.
        self.inner.deinit();
    }
    pub fn state(self: Stream) State {
        return self.inner.phase;
    }
};

// ===========================================================================
// Agent (behavioral, pointer-wrapped)
// ===========================================================================

pub const UserMessage = struct { text: []const u8 };
pub const CompactionResult = agent_mod.Agent.CompactionResult;

pub const Agent = struct {
    inner: *agent_mod.Agent,

    /// Construct an agent. The inner is heap-pinned at `init`, so the
    /// returned `Agent` is a cheap copyable handle ("don't move the Agent"
    /// stops being a rule anyone can violate). `session` is minted via
    /// `store.create()` (fresh) or `resolve`/`latest` (resume). When
    /// `maybe_conversation` is non-null it is adopted (ownership
    /// transferred) — the resume path hands the value returned by
    /// `Session.load`.
    pub fn init(
        allocator: std.mem.Allocator,
        io: std.Io,
        config: *const Config,
        session: Session,
        maybe_conversation: ?Conversation,
    ) !Agent {
        const inner = try allocator.create(agent_mod.Agent);
        inner.* = agent_mod.Agent.init(allocator, io, config, session, maybe_conversation);
        return .{ .inner = inner };
    }

    pub fn deinit(self: Agent) void {
        const allocator = self.inner.allocator;
        self.inner.deinit();
        allocator.destroy(self.inner);
    }

    pub fn registerTool(self: Agent, t: Tool) !void {
        return self.inner.registerTool(t);
    }
    pub fn registerToolSource(self: Agent, src: ToolSource) !void {
        return self.inner.registerToolSource(src);
    }
    pub fn setConfig(self: Agent, cfg: *const Config) void {
        self.inner.setConfig(cfg);
    }
    pub fn run(self: Agent, message: UserMessage) !Stream {
        return .{ .inner = try self.inner.run(.{ .text = message.text }) };
    }

    /// Append a system message to the conversation and persist it (the
    /// `.append` `SystemMode`: it adds to the effective prompt).
    pub fn addSystemMessage(self: Agent, text: []const u8) !void {
        return self.inner.addSystemMessage(text, .append);
    }
    /// Replace the effective system prompt and persist it (the `.replace`
    /// `SystemMode`: it discards all prior system text). On replay the log
    /// reconstructs the same effective prompt.
    pub fn setSystemPrompt(self: Agent, text: []const u8) !void {
        return self.inner.addSystemMessage(text, .replace);
    }

    /// Compact and persist (the explicit `/compact` entry point).
    /// `override_system_prompt` falls back to
    /// `config.compaction.compaction_prompt` when null. `extra` is appended
    /// to the compaction prompt for this run (the `/compact $ARGUMENTS`
    /// path).
    pub fn compact(self: Agent, override_system_prompt: ?[]const u8, extra: ?[]const u8) !CompactionResult {
        return self.inner.compactAndPersist(override_system_prompt, extra);
    }

    /// A borrowed pointer to the agent's live conversation, for in-place
    /// context-management surgery. Valid for the agent's lifetime; do not
    /// retain past it.
    pub fn conversation(self: Agent) *Conversation {
        return &self.inner.conversation;
    }

    /// The id of the session this agent appends to.
    pub fn sessionId(self: Agent) []const u8 {
        return self.inner.session.info.id;
    }
};

// ===========================================================================
// Pricing (data, aliased)
// ===========================================================================

pub const Pricing = pricing_mod.Pricing;
pub const PricingRegistry = pricing_mod.Registry;

// ===========================================================================
// Sessions
// ===========================================================================

pub const SessionStore = session_store_mod.SessionStore;
pub const Session = session_store_mod.Session;
pub const SessionInfo = session_store_mod.SessionInfo;
pub const PersistentMessage = session_store_mod.PersistentMessage;
pub const NullStore = null_store_mod.NullStore;
pub const FileSystemJSONLStore = fs_store_mod.FileSystemJSONLStore;

// ===========================================================================
// Tests
// ===========================================================================

const openai_chat_json = @import("openai_chat_json.zig");
const provider_openai_chat = @import("provider_openai_chat.zig");
const anthropic_messages_json = @import("anthropic_messages_json.zig");
const provider_anthropic_messages = @import("provider_anthropic_messages.zig");
const compaction_mod = @import("compaction.zig");
const sse_mod = @import("sse.zig");
const tool_registry_mod = @import("tool_registry.zig");
const session_mod = @import("session.zig");
const turn_persist_mod = @import("turn_persist.zig");
const image_mod = @import("image.zig");

test {
    // See the note in the old root.zig: gate test logs at `.err` so expected
    // warning-path tests stay quiet.
    std.testing.log_level = .err;

    std.testing.refAllDecls(@This());
    // Internal modules' tests (not part of the public surface, but their
    // tests must still run).
    std.testing.refAllDecls(config_mod);
    std.testing.refAllDecls(conversation_mod);
    std.testing.refAllDecls(agent_mod);
    std.testing.refAllDecls(stream_mod);
    std.testing.refAllDecls(provider_mod);
    std.testing.refAllDecls(tool_mod);
    std.testing.refAllDecls(tool_source_mod);
    std.testing.refAllDecls(tool_registry_mod);
    std.testing.refAllDecls(pricing_mod);
    std.testing.refAllDecls(session_store_mod);
    std.testing.refAllDecls(fs_store_mod);
    std.testing.refAllDecls(null_store_mod);
    std.testing.refAllDecls(session_mod);
    std.testing.refAllDecls(turn_persist_mod);
    std.testing.refAllDecls(compaction_mod);
    std.testing.refAllDecls(sse_mod);
    std.testing.refAllDecls(image_mod);
    std.testing.refAllDecls(openai_chat_json);
    std.testing.refAllDecls(provider_openai_chat);
    std.testing.refAllDecls(anthropic_messages_json);
    std.testing.refAllDecls(provider_anthropic_messages);
}