"""Contextual sidebar scope schema and prompt block renderer.

ContextualScope mirrors the TypeScript ContextualScope type sent by the
Electron renderer when the user opens the side chat anchored to a specific
view.  The renderer ships camelCase keys; Pydantic's alias_generator maps
them to snake_case Python attributes automatically.
"""

from __future__ import annotations

from typing import Literal, Optional

from pydantic import BaseModel, ConfigDict
from pydantic.alias_generators import to_camel


PageType = Literal[
    "timeline",
    "tasks",
    "projects-list",
    "project",
    "note",
]

EntityType = Literal["project", "note", "task", "timeline_event"]


class ContextualScope(BaseModel):
    """Scope payload sent by the Electron renderer for contextual chat.

    The renderer ships camelCase keys (entityType, entityId, ...).  Pydantic's
    alias generator maps them to snake_case Python attrs.
    """

    model_config = ConfigDict(populate_by_name=True, alias_generator=to_camel)

    page: PageType
    entity_type: Optional[EntityType] = None
    entity_id: Optional[str] = None
    entity_name: Optional[str] = None
    project_id: Optional[str] = None
    char_count: Optional[int] = None
    counts: Optional[dict[str, int]] = None
    filters: Optional[dict] = None


def render_scope_block(scope: ContextualScope) -> str:
    """Produce a single-paragraph human-readable summary of the current view
    for injection into the contextual agent system prompt.

    Never emits internal ids — only names.  The LLM is told to use names in
    prose; ids travel through tool calls.
    """
    if scope.entity_type == "project":
        c = scope.counts or {}
        return (
            f"User is viewing the project {scope.entity_name!r}. "
            f"{c.get('tasks', 0)} tasks, "
            f"{c.get('notes', 0)} notes, "
            f"{c.get('milestones', 0)} milestones."
        )
    if scope.entity_type == "note":
        return (
            f"User is viewing the note {scope.entity_name!r} "
            f"({scope.char_count or 0} characters)."
        )
    if scope.page == "tasks":
        return "User is viewing the global Tasks list (all projects)."
    if scope.page == "timeline":
        return "User is viewing the global Timeline view."
    if scope.page == "projects-list":
        return "User is viewing the Projects list."
    return f"User is on page {scope.page}."