"""Pydantic request/response schemas (API contract)."""
from __future__ import annotations

import uuid
from datetime import datetime
from typing import Annotated, Any, Literal

from pydantic import (
    BaseModel,
    ConfigDict,
    Field,
    SerializerFunctionWrapHandler,
    field_validator,
    model_serializer,
)


class HealthResponse(BaseModel):
    status: str
    db: str
    version: str
    environment: str


class SuggestionList(BaseModel):
    suggestions: list[str]


class HistoryTurn(BaseModel):
    """One prior chat turn the client sends with ``POST /api/chat``
    (phase 74, TODO L4).

    The endpoint stays stateless (A10): the client's ``bor.chat.v1``
    conversation record (minus the question about to be asked) is
    provided in the request body as ``history`` so a follow-up question
    reaches the model together with the exchange so far — and, for
    preserve-thinking models, with the prior brain turns' thinking (the
    record has carried the ``thinking`` key since phase 17).

    ``thinking`` travels to the model as ``reasoning_content`` on the
    assistant message (the wire convention :mod:`app.rag.llm` already
    documents for the response side) — only when non-empty (A4).
    ``text`` mirrors :attr:`ChatMessage.text`'s answer shape; long
    answers (and the scratchpads that ride along as ``thinking``) both
    run to tens of kilobytes of text, so both share the same loose
    boundary cap. These are boundary sanity caps only — the real
    trimming budget is the settings pair ``history_max_turns`` /
    ``history_max_chars`` (``app.config``, A3: a capped-out turn is
    dropped whole, never truncated). The old 4000-char text cap was
    stricter than the 24_000-char default total budget and rejected
    any second turn in a chat whose history held a long answer (422 —
    found by the phase-42 E2E suite on the phase-76 shell).
    """

    who: Literal["user", "brain"]
    text: str = Field(min_length=1, max_length=32_000)
    thinking: str | None = Field(default=None, max_length=32000)


class ChatRequest(BaseModel):
    """``POST /api/chat`` body: the current question plus the optional
    prior turns (phase 74 — the client-provided history, stateless per
    A10).

    ``history`` is the client's earlier turns, oldest first (the
    ``bor.chat.v1`` record minus the current question); the mapper
    (:func:`app.rag.prompts.history_to_messages`) trims it newest-first
    against the settings budgets and maps it to model messages. The
    schema-level ``max_length=100`` is a DoS sanity ceiling only — the
    config budgets do the real trimming (A3). Absent or empty keeps the
    request byte-identical to pre-phase-74: the model sees exactly the
    two-message ``[system, user]`` request.
    """

    message: str = Field(min_length=1, max_length=4000)
    history: list[HistoryTurn] = Field(default_factory=list, max_length=100)

class LoginRequest(BaseModel):
    """``POST /api/login`` body (phase 16): the single admin's password.

    An empty or wrong password is a 401 with one generic detail — never a
    422 that would hint at input-shape differences.
    """

    password: str = ""


class WhoamiResponse(BaseModel):
    """``GET /api/whoami`` (phase 16; phase 79 added the ``user`` role)
    — drives all UI gating. ``authenticated`` is true for admin AND
    user; the UI's admin-only surfaces key off ``role === "admin"``.
    """

    authenticated: bool
    role: str  # "admin" | "user" | "anonymous"


class SourceRef(BaseModel):
    """One indexed document as cited in an answer (the SSE ``done``
    event's ``sources`` item — PLAN §4 — and, since phase 50, the
    ``sources`` list of a saved-chat message).

    Phase 83 (SEC-05): the caps mirror the ``documents`` column lengths
    (``source`` ``String(120)``, ``path`` ``String(1000)``, ``title``
    ``String(500)``). A :class:`SourceRef` is built from ``documents``
    rows server-side, so every server-built SSE ref fits by construction
    (A3: the SSE path is provably unaffected); the cap binds only
    client-saved refs — bounded at the boundary with a 422.
    """

    source: str = Field(max_length=120)
    path: str = Field(max_length=1000)
    title: str = Field(max_length=500)


class ChatThinkingEvent(BaseModel):
    """SSE thinking event: one chunk of the model's reasoning (phase 17).

    PLAN §4 extension (A15, owner permission 2026-08-23): frames of the
    shape ``{type: "thinking", text: str}`` stream ahead of the
    ``delta`` frames in practice (the model reasons before it answers). The
    client renders them in a collapsible "Thinking" block; the ``done``
    event shape is unchanged and thinking text never travels on it.
    Sibling of :class:`ChatErrorEvent`.
    """

    type: str = "thinking"
    text: str


class ChatToolEvent(BaseModel):
    """SSE frame for one agent tool call (phase 37, PLAN §4 extension).

    A15 extension (owner permission 2026-08-26; the grep added in phase
    68; phase 70 aligned the surface to the harness-trained
    ``ls`` / ``read`` / ``grep`` — owner permission 2026-09-03): a
    grounded turn may call the server-side document tools (``ls`` /
    ``read`` / ``grep``, see :mod:`app.rag.agent`); each model-requested
    call streams as ``{type: "tool", name: str, argument: str | null}``
    ahead of the answer's ``delta`` frames. ``argument`` is the single
    string argument the model passed — ``read``'s ``path`` (the combined
    ``source/path``), ``grep``'s ``pattern``, ``ls``'s ``path`` — or
    null (a non-string value, a model error the backend refuses, and an
    omitted argument both yield null). The client renders each frame as
    a "calling tool" line/state (phase 37 task 05); the ``delta`` /
    ``done`` shapes are unchanged — the read document is reflected in
    ``done.sources`` instead (a grep adds no source: it is a locator,
    locked A5).
    """

    type: Literal["tool"] = "tool"
    name: str  # "ls" | "read" | "grep" (whatever AGENT_TOOLS names)
    argument: str | None = None  # the single string argument passed, or null


class ChatToolResultEvent(BaseModel):
    """SSE frame for one executed tool call whose result was truncated
    (phase 95, ``TODO.md`` L5).

    A15 extension (owner permission 2026-09-10 — recorded in the phase 95
    overview ``00_phase.md``; PLAN.md is being redone by the owner): the
    SSE event-type list grows from six to SEVEN — ``thinking``,
    ``tool``, ``retry``, ``delta``, ``done``, ``error`` and this
    optional ``tool_result``. The frame is strictly ADDITIVE: existing
    frames and clients are untouched (a client that does not know the
    type simply ignores it), and it is emitted ONLY for a truncated
    ``read`` — one frame per truncated read, carrying the counts the UI
    renders as "(truncated — showing N of M chars)". It always follows
    the matching :class:`ChatToolEvent` frame for the same call (the
    line is already on screen; the marker lands a beat later — the
    phase-37/48 tool-line lifecycle is untouched). ``argument`` is the
    combined ``source/path`` the model passed (identical to the matching
    ``tool`` frame's argument, so the client can match the two); a
    non-truncated read streams NO frame of this type.
    """

    type: str = "tool_result"
    name: str  # the tool that was executed (always "read" today)
    argument: str | None = None  # the model's argument (combined source/path)
    truncated: bool = True  # always True on a sent frame (the emission trigger)
    chars_shown: int = Field(ge=0)  # the cap kept (settings.read_max_chars)
    chars_total: int = Field(ge=0)  # the document's true length


class ChatDoneEvent(BaseModel):
    """Final SSE event of a chat turn: metadata for the finished answer."""

    type: str = "done"
    deflected: bool
    sources: list[SourceRef]
    suggestions: list[str] = []


class ChatErrorEvent(BaseModel):
    """SSE error event: a turn that cannot complete (PLAN §4).

    The client's loading-feedback state machine (phase 06) keys off this
    exact shape — ``{type: "error", detail: str}`` — to flip to the error
    state and re-enable the send button.
    """

    type: str = "error"
    detail: str


class ChatRetryEvent(BaseModel):
    """SSE retry event: an LLM request is restarted before the first token
    (phase 67, owner-locked 2026-09-01).

    Sibling of :class:`ChatErrorEvent`, but transient — the client shows a
    live status on the existing ``#send-status`` line (locked A4:
    "Communication interrupted — retrying (n of N)…") and the send button
    stays the Stop control; it never flips the state machine to error. It
    is only ever sent when the failed attempt had NOT streamed a single
    output frame yet (locked A2: no thinking/tool/delta emitted) — once
    tokens are flowing, a failure is terminal (the ``error`` frame) and
    this event cannot appear.

    ``attempt`` is the 1-based number of the attempt the endpoint is about
    to try next (what the endpoint sends — the first failure of a
    4-attempt budget carries ``attempt=2``); ``max_attempts`` is the total
    attempt budget (``llm_retries + 1``).
    """

    type: Literal["retry"] = "retry"
    attempt: int
    max_attempts: int


class DocSummary(BaseModel):
    """One indexed document as shown on the Sources page / API."""

    id: str
    source: str
    path: str
    title: str
    chunks: int
    indexed_at: str


class DocList(BaseModel):
    """Response of ``GET /api/docs`` (empty list → designed empty state)."""

    documents: list[DocSummary]


class DocContent(BaseModel):
    """One indexed document's full content (feeds the viewer page, phase 10)."""

    source: str
    path: str
    title: str
    format: str
    #: Lite-model summary (phase 30) — non-markdown A9 docs only; None for
    #: markdown documents, pre-phase-30 rows, and the fail-soft path where
    #: summary generation failed but the document was still indexed.
    summary: str | None = None
    content: str
    indexed_at: str
    chunks: int


class SummaryUpdate(BaseModel):
    """``PATCH /api/documents/summary`` body (phase 57, task 01).

    ``source`` / ``path`` name the indexed document (the same pair the
    public ``GET /api/documents/content`` looks up); ``summary`` is the
    raw new text. The API strips it before storing — an
    empty/whitespace-only value is the *clear* operation (a first-class
    action, phase 57 D4), not a 422. Unconstrained on purpose: unknown
    pairs must 404 as "document not found" (row-lookup semantics),
    exactly like the public content endpoint.
    """

    source: str
    path: str
    summary: str


class SummaryResult(BaseModel):
    """``PATCH /api/documents/summary`` response (phase 57, task 01).

    ``summary`` is the stored text after the change (``null`` after a
    clear — the viewer's summary box hides on null) and ``chunks`` the
    document's post-change total chunk count: an update leaves the
    content chunks untouched (the count is unchanged — only the single
    ``is_summary`` chunk is replaced), a clear drops one (the
    ``is_summary`` chunk is deleted).
    """

    source: str
    path: str
    summary: str | None
    chunks: int


class SteeringNoteIn(BaseModel):
    """``POST /api/steering`` body: one tuning instruction (phase 15).

    The note is trimmed *before* the length constraints run, so a
    whitespace-only body is a 422 and a 2000-char note with surrounding
    spaces still passes.
    """

    note: str = Field(min_length=1, max_length=2000)

    @field_validator("note", mode="before")
    @classmethod
    def _trim_note(cls, v: object) -> object:
        return v.strip() if isinstance(v, str) else v


class SteeringNoteUpdate(BaseModel):
    """``PUT /api/steering/{id}`` body: a new tuning instruction (phase 27).

    Mirrors :class:`SteeringNoteIn` — the note is trimmed *before* the
    length constraints run, so an empty/whitespace body is a 422 and a
    full replacement that is ≤2000 chars after the trim still passes.
    """

    note: str = Field(min_length=1, max_length=2000)

    @field_validator("note", mode="before")
    @classmethod
    def _trim_note(cls, v: object) -> object:
        return v.strip() if isinstance(v, str) else v


class SteeringNote(BaseModel):
    """One stored steering note (API shape — ISO-8601 ``created_at``)."""

    id: uuid.UUID
    note: str
    created_at: datetime


class SteeringNoteList(BaseModel):
    """``GET /api/steering`` response: all notes, newest first."""

    notes: list[SteeringNote]


class GitSourceIn(BaseModel):
    """``POST /api/git-sources`` body (phase 35, task 02; ``kind``, phase 38).

    ``kind`` selects the source kind and which field carries its location:

    * ``"git"`` (default) — ``url`` is the repo URL. Mirrors the
      phase-35 contract: trimmed *before* the length constraints run, so a
      whitespace-only body is a 422 and a URL with surrounding spaces is
      stored clean. Shape validation (``https://``, ``ssh://``, ``git@``)
      and the kind-field rules (url present, no path) happen in the API
      layer so the 422/409 details stay fixed strings that never echo the
      input (credential safety).
    * ``"local"`` — ``path`` is an existing directory on the server.
      Trimmed here; the API layer then ``expanduser()``s it and requires an
      absolute existing directory (else 422 naming the path — the path is
      not a secret, unlike a git URL) and no ``url``.

    ``ignore_paths`` (phase 89) is optional at create time (absent →
    ``[]``) and carries the RAW box lines — trimming/normalization happens
    in the API layer, not the schema, so the A4 422 details stay fixed
    strings (the router's credential-safety discipline, applied for
    consistency).
    """

    kind: Literal["git", "local"] = "git"
    url: str | None = Field(default=None, min_length=1, max_length=500)
    path: str | None = Field(default=None, min_length=1, max_length=2000)
    ignore_paths: list[str] | None = Field(default=None)

    @field_validator("url", mode="before")
    @classmethod
    def _trim_url(cls, v: object) -> object:
        return v.strip() if isinstance(v, str) else v

    @field_validator("path", mode="before")
    @classmethod
    def _trim_path(cls, v: object) -> object:
        return v.strip() if isinstance(v, str) else v


class GitSourceOut(BaseModel):
    """One created git source as returned by ``POST`` (phase 35, task 02).

    ``id`` / ``added_at`` are non-null for a stored row. ``url`` is the
    row's location column: the repo URL for ``kind=git`` rows and, for
    ``kind=local`` rows, the stored (expanded) directory path — the
    phase-35 response shape is unchanged by phase 38, so a local 201
    reports its path in ``url`` and the full row (``kind`` + ``path``)
    via ``GET``. ``ignore_paths`` (phase 89) is the stored, normalized
    list — non-null (a row created without it reports ``[]``).
    """

    id: uuid.UUID | None
    url: str
    added_at: datetime | None
    ignore_paths: list[str]


class GitSourceRow(BaseModel):
    """One row of ``GET /api/git-sources`` (phase 35; ``kind``/``path``,
    phase 38, task 02).

    ``kind`` discriminates the row: git rows (and the git-only
    ``BOR_GIT_SOURCES`` env-fallback rows) carry ``url`` and
    ``path: null``; local rows carry ``path`` (the absolute directory,
    expanded) and the same string in ``url`` (the table's NOT-NULL
    location column). ``id`` / ``added_at`` are nullable: env-fallback
    rows (table empty) carry neither. ``ignore_paths`` (phase 89) is the
    row's stored, normalized list — env-fallback rows (no DB row to
    store a list on) report ``[]``.
    """

    id: uuid.UUID | None
    kind: Literal["git", "local"]
    url: str
    path: str | None
    added_at: datetime | None
    ignore_paths: list[str]


class GitSourceIgnoreIn(BaseModel):
    """``PATCH /api/git-sources/{source_id}`` body (phase 89, A5).

    ``ignore_paths`` is REQUIRED — the box's lines in REPLACE semantics:
    the body list (normalized + A4-validated in the API layer, with the
    fixed-detail 422s) becomes the row's whole list — an empty list
    clears all; an absent field is a 422 with the model's own detail.
    Entries are RAW box lines: normalization + the A4 limits are
    enforced in the API layer so the 422 details stay fixed strings
    (the router's credential-safety discipline, applied for
    consistency).
    """

    ignore_paths: list[str]


class GitSourceList(BaseModel):
    """``GET /api/git-sources`` response (phase 35, task 02).

    ``from_env`` is True only when the ``git_sources`` table is empty and
    the list comes from ``BOR_GIT_SOURCES`` (the phase's locked fallback
    — env rows are git-only and report ``kind: "git"``, ``path: null``);
    once the table has rows the env var is ignored and ``from_env`` is
    False — the UI is the source of truth.
    """

    sources: list[GitSourceRow]
    from_env: bool


class UploadAccepted(BaseModel):
    """``POST /api/git-sources/upload`` 202 response (phase 64, task 03).

    The archive is **safely on disk** — this is the "successfully
    uploaded" moment the Sources page toasts on (phase 64 A2). The rest
    (unpack → swap → row upsert — and nothing else: no model check, no
    import, no overview refresh, phase 90 A1 — the scan is the RAG
    page's "Sync sources" button's job) runs in a background task behind
    ``GET /api/git-sources/upload/status``, whose ``success`` ``detail``
    carries the no-count ``{"message": "uploaded"}`` payload (phase 90
    A2 — the status key set is unchanged; the UI composes the user
    copy).
    """

    detail: str = "upload received"
    name: str


class ToolCall(BaseModel):
    """One agent tool-call record (the phase-37 ``tools`` record shape).

    Mirrors the ``{name, argument}`` pair the SSE ``tool`` frames carry
    (PLAN §4 extension; phase 70): ``argument`` is the single string
    argument the model passed (``read``'s combined ``source/path``,
    ``grep``'s pattern, ``ls``'s scope) or null. Stored inside
    :class:`ChatMessage.tools` so a saved chat restores the "calling
    tool" lines pixel-identical (phase 50). Saved chats persisting the
    pre-phase-70 tool names still validate — ``name`` is opaque
    (no migration, locked).

    Phase 83 (SEC-05) bounds the anonymous write surface: ``name`` ≤
    100 (a tool name longer than that is not a real call — the
    ``AGENT_TOOLS`` names are short) and ``argument`` ≤ 2000 (the
    combined ``source/path`` identity is ≤ 120 + 1 + 1000; 2 000 is 2×
    headroom for a grep pattern).

    Phase 95 (task 02): the truncation marker the UI renders next to the
    Reading line rides the SAME record — ``truncated`` (default False:
    the pre-phase-95 shape) + the two non-negative counts. Small
    additive fields with defaults, no migration (``ChatMessage.tools``
    is JSON) — a saved chat written before phase 95 (no fields) validates
    UNCHANGED (the phase-50 backward-compat rule) and renders without
    the marker.
    """

    name: str = Field(max_length=100)
    argument: str | None = Field(default=None, max_length=2000)
    truncated: bool = False
    chars_shown: int | None = Field(default=None, ge=0)
    chars_total: int | None = Field(default=None, ge=0)


#: One suggestion chip (phase 83, A1): a short deterministic string —
#: ``derive_suggestions``'s output runs to ~80 chars, so 200 chars is
#: the boundary sanity cap. Annotated alias: the JSON shape stays a
#: plain string (only the value bound is added).
_Chip = Annotated[str, Field(max_length=200)]


class ChatMessage(BaseModel):
    """One conversation record in the ``bor.chat.v1`` localStorage shape
    (phase 14) — the stored ``messages`` payload of a saved chat (phase 50).

    ``{who, text, sources?, deflected?, suggestions?, thinking?, tools?,
    stopped?}`` — raw text, never HTML, so a saved chat restores
    pixel-identical through the existing ``renderStoredMessage`` path.
    ``extra="forbid"`` rejects unknown keys (a corrupted or HTML-shaped
    payload, e.g. a stray ``<b>``-ish extra key) at the boundary with a
    422, so nothing outside this shape can poison a restored
    conversation.

    Phase 83 (SEC-05) bounds the anonymous write surface (``POST/PUT
    /api/chats`` is public — the row id is the credential, phase 55 A1):
    ``text`` / ``thinking`` carry :class:`HistoryTurn`'s 32 000 caps
    (a single message longer than that is already rejected on the chat
    path, so a saved chat can never legitimately carry more), and the
    nested lists get length caps (``max_length``) sized to the realistic
    ``bor.chat.v1`` record the UI produces (``sources`` ≤ 20 — top-N docs
    + agent reads; ``suggestions`` ≤ 50 chips of ≤ 200 chars; ``tools``
    ≤ 50 — one entry per tool call, the round cap is 10). Only value
    bounds were added — the accepted/rejected KEYS are unchanged.
    """

    model_config = ConfigDict(extra="forbid")

    who: Literal["user", "brain"]
    text: str = Field(min_length=1, max_length=32_000)
    sources: list[SourceRef] | None = Field(default=None, max_length=20)
    deflected: bool | None = None
    suggestions: list[_Chip] | None = Field(default=None, max_length=50)
    thinking: str | None = Field(default=None, max_length=32_000)
    tools: list[ToolCall] | None = Field(default=None, max_length=50)
    stopped: bool | None = None


class SavedChatCreate(BaseModel):
    """``POST /api/chats`` body (phase 50, task 02; ``share``, phase 51
    task 02).

    ``title`` is optional: when absent or blank the API auto-titles the
    row (the first user message's text, whitespace-collapsed, truncated
    to 120 chars — the owner-locked convention). ``messages`` must be
    non-empty — a saved chat with nothing to restore is meaningless —
    and, since phase 83 (SEC-05), at most 200 items: well past any realistic
    conversation (the chat history budget itself is 40 turns) and far
    below a DoS-sized list on the anonymous write surface.

    ``share`` (phase 51, owner-locked 2026-08-29): when true, the row is
    shared in the SAME commit — ``share_token = uuid.uuid4()`` is set on
    the fresh row before the INSERT, so one request saves AND shares
    (the chat page's Share button on an unsaved conversation, the
    save-then-share contract). The response then carries ``share_url``
    (see :class:`SavedChatOut`). Default false — a plain Save is
    unchanged by phase 51.
    """

    title: str | None = Field(default=None, max_length=500)
    messages: list[ChatMessage] = Field(min_length=1, max_length=200)
    share: bool = False


class SavedChatUpdate(BaseModel):
    """``PUT /api/chats/{chat_id}`` body (phase 50, task 02).

    ``messages`` is a full replacement (the re-Save upsert semantics —
    re-Saving the same conversation updates the same row, never a new
    one) and carries the same bounds as :class:`SavedChatCreate.messages`
    (phase 83, SEC-05: non-empty, ≤ 200 items). ``title`` is replaced
    only when supplied — an absent (or blank) ``title`` keeps the row's
    current title.
    """

    title: str | None = Field(default=None, max_length=500)
    messages: list[ChatMessage] = Field(min_length=1, max_length=200)


def _drop_absent_share_url(model: BaseModel, handler: SerializerFunctionWrapHandler) -> Any:
    """The ``share_url`` omission rule (phase 51, task 02): ``None`` →
    ABSENT from the JSON (not ``"share_url": null``) — an unshared chat
    exposes no share surface at all, and the History column renders the
    unshared state from the key's absence.

    A ``mode="wrap"`` model serializer: the default (recursive) dump runs
    first, then only the TOP-LEVEL key is dropped when null. The
    recursion matters — a route-level ``response_model_exclude_none``
    would also drop the nested ``ChatMessage`` nulls (``sources: null``
    and friends), which the byte-identical round-trip contract (phase
    50) forbids.
    """
    data = handler(model)
    if data.get("share_url") is None:
        data.pop("share_url", None)
    return data


class SavedChatOut(BaseModel):
    """One saved chat, full payload (create/get/put response, phase 50;
    ``share_url``, phase 51 task 02; ``stale``, phase 53 task 03).

    ``messages`` round-trips the ``bor.chat.v1`` record list losslessly
    — the restore path is pixel-identical by construction.

    ``share_url`` (phase 51): ``"/shared/<token>"`` while the chat is
    shared, ABSENT from the JSON when unshared (``None`` → dropped by
    :func:`_drop_absent_share_url` — no ``null`` in the wire shape).

    ``stale`` (phase 53): true iff the row's ``sources_version`` stamp
    is behind the current ``sources_meta`` generation — the answer
    predates the latest KB-changing sync. Computed server-side (the
    client never does staleness math); ``SharedChatOut`` deliberately
    carries no staleness surface (the public snapshot is frozen by
    design, phase 51).
    """

    id: uuid.UUID
    title: str
    created_at: datetime
    updated_at: datetime
    message_count: int
    messages: list[ChatMessage]
    share_url: str | None = None
    #: Required (no default): the API must always compute staleness
    #: server-side — there is no wire shape without the flag.
    stale: bool

    @model_serializer(mode="wrap")
    def _serialize(self, handler: SerializerFunctionWrapHandler) -> Any:
        return _drop_absent_share_url(self, handler)


class SavedChatRow(BaseModel):
    """One row of ``GET /api/chats`` (the History page's list shape,
    phase 50; ``share_url``, phase 51 task 02).

    No payloads in the list — the row carries only what the table needs
    (Title, Messages count, Updated). ``share_url`` is populated here so
    the History page's Share column renders straight from ``GET
    /api/chats`` — no second fetch per row (``None`` → absent, the same
    omission rule as :class:`SavedChatOut`). ``stale`` (phase 53) feeds
    the History page's Stale column the same way: one ``GET`` powers
    every column.
    """

    id: uuid.UUID
    title: str
    updated_at: datetime
    message_count: int
    share_url: str | None = None
    #: Required (no default) — see :attr:`SavedChatOut.stale`.
    stale: bool

    @model_serializer(mode="wrap")
    def _serialize(self, handler: SerializerFunctionWrapHandler) -> Any:
        return _drop_absent_share_url(self, handler)


class SavedChatList(BaseModel):
    """``GET /api/chats`` response: saved chats, latest activity first
    (``updated_at desc, id desc``)."""

    chats: list[SavedChatRow]


class SharedChatOut(BaseModel):
    """``GET /api/shared/{token}`` body (phase 51, task 01) — the PUBLIC
    read shape of a shared chat.

    Deliberately minimal: ``title`` + ``messages`` only. No id, no
    timestamps, no token, no ``message_count`` — a shared chat is a
    content snapshot, not a handle: nothing in the body can be turned
    back into an admin-surface request, and the token itself never
    round-trips (it is the URL, not data).
    """

    title: str
    messages: list[ChatMessage]


class ShareOut(BaseModel):
    """``POST /api/chats/{chat_id}/share`` response (phase 51, task 01).

    ``share_url`` is the path (``/shared/<token>``) the UI copies into
    the clipboard — the owner's own origin supplies the scheme/host.
    Idempotent: a re-share returns the existing, unchanged token.
    """

    chat_id: uuid.UUID
    share_url: str


class UnshareOut(BaseModel):
    """``POST /api/chats/{chat_id}/unshare`` response (phase 51, task 01).

    ``shared: false`` is reported unconditionally — the endpoint is
    idempotent, so an already-unshared chat unshares cleanly (200).
    """

    chat_id: uuid.UUID
    shared: bool


class DocDraftCreate(BaseModel):
    """``POST /api/doc-drafts`` body (phase 59, task 02): one completed
    chat answer about to become documentation.

    ``title`` arrives client-side as the last user question
    (whitespace-collapsed, ≤120 chars — the chat auto-title convention,
    phase 50); ``path`` as ``docs/<slug>.md``; ``body`` is the answer's
    raw markdown (never HTML — the ``bor.chat.v1`` record's ``text``,
    the phase-50/51 round-trip convention). The path guard-rails (task
    02 — repo-relative, no ``..``, no absolute path) run in the API
    layer so the 422 details stay fixed strings; the max lengths mirror
    the ``documents`` table (title 500, path 1000).
    """

    title: str = Field(min_length=1, max_length=500)
    path: str = Field(min_length=1, max_length=1000)
    body: str = Field(min_length=1)


class DocDraftUpdate(BaseModel):
    """``PUT /api/doc-drafts/{token}`` body (phase 59, task 02): a
    partial update — each field is replaced only when supplied (absent
    keeps the row's current value; present must be non-empty — the
    ``SavedChatUpdate`` optional-title pattern, extended to all three
    editable fields). The same path guard-rails as create run in the
    API layer when ``path`` is supplied.
    """

    title: str | None = Field(default=None, min_length=1, max_length=500)
    path: str | None = Field(default=None, min_length=1, max_length=1000)
    body: str | None = Field(default=None, min_length=1)


class DocDraft(BaseModel):
    """One draft row, full payload (create/get/put response, phase 59).

    ``token`` is the URL credential (``/doc-edit.html?draft=<token>``
    — the unguessable ``uuid4``, the share-token trust model, phase
    51). ``status`` is ``draft`` until the push endpoint commits +
    pushes the file, then ``pushed`` with ``branch`` / ``commit_sha``
    recorded (both NULL while still a draft). Datetimes serialize
    ISO-8601 on the wire (pydantic default).
    """

    token: uuid.UUID
    title: str
    path: str
    body: str
    status: str
    branch: str | None = None
    commit_sha: str | None = None
    created_at: datetime
    updated_at: datetime


class DocDraftPushed(BaseModel):
    """``POST /api/doc-drafts/{token}/push`` success response (phase 59,
    task 04): the commit + ``git push --ff-only`` landed — ``branch``
    is the ``BOR_DOCS_BRANCH`` name and ``commit_sha`` the pushed
    branch's new HEAD (the edit screen's branch + sha feedback; it must
    equal ``git rev-parse <branch>`` in the repo — the E2E source of
    truth is the bare repo's state, not the UI alone).
    """

    status: Literal["pushed"] = "pushed"
    branch: str
    commit_sha: str


class TokenCreateRequest(BaseModel):
    """``POST /api/tokens`` body (phase 79, task 02): one named token
    to generate and hand out.

    ``label`` is the hand-out name (e.g. "alice") — display-only, NOT
    unique (two tokens may share a label). Trimmed *before* the length
    constraints run, so a whitespace-only body is a 422 and a label with
    surrounding spaces is stored clean (the ``SteeringNoteIn`` house
    ``ValueError`` pattern — fail loud at the boundary).
    """

    label: str = Field(min_length=1, max_length=120)

    @field_validator("label", mode="before")
    @classmethod
    def _trim_label(cls, v: object) -> object:
        return v.strip() if isinstance(v, str) else v


class TokenCreated(BaseModel):
    """``POST /api/tokens`` 201 response (phase 79, task 02).

    The ONLY schema in the codebase that carries the plaintext ``token``
    — the wire moment it exists exactly once (A4). Every other response
    shape (the list row, whoami, …) exposes display fields only: the
    stored credential is the hash, and the hash itself is never a wire
    field either.
    """

    id: uuid.UUID
    label: str
    token: str
    created_at: datetime


class TokenListItem(BaseModel):
    """One row of ``GET /api/tokens`` (phase 79, task 02).

    Deliberately secret-free: NO ``token`` field and NO ``token_hash``
    field exist on this shape — the list never carries a credential in
    either form (A4). ``revoked`` is derived server-side from
    ``revoked_at is not None`` (the UI renders the Active/Revoked state
    from the flag, not the timestamp).
    """

    id: uuid.UUID
    label: str
    created_at: datetime
    last_used_at: datetime | None
    revoked: bool


class TokenList(BaseModel):
    """``GET /api/tokens`` response: all tokens, newest first
    (``created_at desc, id desc``)."""

    tokens: list[TokenListItem]


class TokenAuthRequest(BaseModel):
    """``POST /api/token-auth`` body (phase 79, task 03): the plaintext
    token a handed-out user presents at the in-app gate.

    Deliberately NO min-length validator: an empty/whitespace token is a
    MALFORMED login attempt — the endpoint 401s ``invalid token`` (the
    phase-16 generic-401 pattern, one message for every failure: no
    enumeration). A 422 here would hint at input-shape differences on a
    credential endpoint, so the shape is just ``str`` and the endpoint
    owns the ``token.strip()`` check.
    """

    token: str


class UiSettingsIn(BaseModel):
    """``PUT /api/ui-settings`` body (phase 91, task 01): a FULL
    replacement of the single ``ui_settings`` row.

    Every field is ``str | None`` — present = a new value (strings are
    trimmed; empty after the trim is the CLEAR operation, stored as
    NULL; colors must be ``#rrggbb`` and are lowercased on store),
    ``null``/absent = "back to the default" (stored as NULL — the Reset
    button's all-null PUT is exactly the "defaults" operation). The
    API layer runs the trim/length/hex validation so the 422 details
    name the offending field (the house fixed-detail style); the
    built-in→NULL normalization (a color equal to its built-in is
    stored as NULL — "save the defaults" must leave the row empty, the
    no-op injection contract) happens there too, next to the palette
    it normalizes against.
    """

    app_name: str | None = None
    input_placeholder: str | None = None
    footer_text: str | None = None
    bg: str | None = None
    surface: str | None = None
    ink: str | None = None
    ink_soft: str | None = None
    line: str | None = None
    grid_line: str | None = None
    brand: str | None = None
    brand_soft: str | None = None
    brand_ink: str | None = None
    # The 8 semantic state colors (phase 93 — B3 revised): the same
    # contract as the 9 identity colors (``null`` = back to the
    # built-in; ``#rrggbb`` is validated + lowercased by the API).
    ok_bg: str | None = None
    ok_ink: str | None = None
    err_bg: str | None = None
    err_ink: str | None = None
    err_line: str | None = None
    accent_bg: str | None = None
    accent_ink: str | None = None
    accent_line: str | None = None


class UiSettingsOut(BaseModel):
    """Effective UI settings (``GET``/``PUT /api/ui-settings`` response,
    phase 91, task 01; 17 colors since phase 93).

    All 20 values (3 strings + 17 palette colors — 9 identity + 8
    semantic state), all non-null strings: the resolver's
    DB-over-env / DB-over-built-in merge (B1), so the tab always shows
    the LIVE theme — a fresh (row-missing) deployment reports the env
    strings and the built-in palette (the semantic colors report their
    built-ins — the effective values, the NULL = built-in rule).
    """

    app_name: str
    input_placeholder: str
    footer_text: str
    bg: str
    surface: str
    ink: str
    ink_soft: str
    line: str
    grid_line: str
    brand: str
    brand_soft: str
    brand_ink: str
    ok_bg: str
    ok_ink: str
    err_bg: str
    err_ink: str
    err_line: str
    accent_bg: str
    accent_ink: str
    accent_line: str