#!/usr/bin/env python3
# -*- coding: utf-8 -*-
"""
Session Start Hook - Inject structured context
"""
from __future__ import annotations

# IMPORTANT: Suppress all warnings FIRST
import warnings
warnings.filterwarnings("ignore")

import json
import os
import re
import shlex
import subprocess
import sys
from io import StringIO
from pathlib import Path


def _normalize_windows_shell_path(path_str: str) -> str:
    """Normalize Unix-style shell paths to real Windows paths.

    On Windows, shells like Git Bash / MSYS2 / Cygwin may report paths like
    `/d/Users/...` or `/cygdrive/d/Users/...`. `Path.resolve()` will misinterpret
    these as `D:/d/Users...` on drive D: (or similar), breaking repo root
    detection.

    This function is intentionally conservative: it only rewrites patterns that
    unambiguously represent a drive letter mount.
    """
    if not isinstance(path_str, str) or not path_str:
        return path_str

    # Only relevant on Windows; keep other platforms untouched.
    if not sys.platform.startswith("win"):
        return path_str

    p = path_str.strip()

    # Already a Windows drive path (C:\... or C:/...)
    if re.match(r"^[A-Za-z]:[\/]", p):
        return p

    # MSYS/Git-Bash style: /c/Users/... or /d/Work/...
    m = re.match(r"^/([A-Za-z])/(.*)", p)
    if m:
        drive, rest = m.group(1).upper(), m.group(2)
        rest = rest.replace('/', '\\')
        return f"{drive}:\\{rest}"

    # Cygwin style: /cygdrive/c/Users/...
    m = re.match(r"^/cygdrive/([A-Za-z])/(.*)", p)
    if m:
        drive, rest = m.group(1).upper(), m.group(2)
        rest = rest.replace('/', '\\')
        return f"{drive}:\\{rest}"

    # WSL mounted drive (sometimes leaked into env): /mnt/c/Users/...
    m = re.match(r"^/mnt/([A-Za-z])/(.*)", p)
    if m:
        drive, rest = m.group(1).upper(), m.group(2)
        rest = rest.replace('/', '\\')
        return f"{drive}:\\{rest}"

    return path_str


FIRST_REPLY_NOTICE = """<first-reply-notice>
First visible reply: say once in Chinese that Trellis SessionStart context is loaded, then answer directly.
This notice is one-shot: do not repeat it after the first assistant reply in the same session.
</first-reply-notice>"""

# Force UTF-8 on stdin/stdout/stderr on Windows. Default codepage there is
# cp936 / cp1252 / etc. — non-ASCII content (Chinese task names, prd snippets)
# both in stdin (hook payload from host CLI) and stdout (our emitted blocks)
# raises UnicodeDecodeError / UnicodeEncodeError. Equivalent to `python -X utf8`
# but applied per-stream so we don't depend on host CLI's command wiring.
if sys.platform.startswith("win"):
    import io as _io
    for _stream_name in ("stdin", "stdout", "stderr"):
        _stream = getattr(sys, _stream_name, None)
        if _stream is None:
            continue
        if hasattr(_stream, "reconfigure"):
            try:
                _stream.reconfigure(encoding="utf-8", errors="replace")  # type: ignore[union-attr]
            except Exception:
                pass
        elif hasattr(_stream, "detach"):
            try:
                setattr(sys, _stream_name, _io.TextIOWrapper(_stream.detach(), encoding="utf-8", errors="replace"))
            except Exception:
                pass



def _has_curated_jsonl_entry(jsonl_path: Path) -> bool:
    """Return True iff jsonl has at least one row with a ``file`` field.

    A freshly seeded jsonl only contains a ``{"_example": ...}`` row (no
    ``file`` key) — that is NOT "ready". Readiness requires at least one
    curated entry. Matches the contract used by hook-inject and pull-based
    sub-agent context loaders.
    """
    try:
        for line in jsonl_path.read_text(encoding="utf-8").splitlines():
            line = line.strip()
            if not line:
                continue
            try:
                row = json.loads(line)
            except json.JSONDecodeError:
                continue
            if isinstance(row, dict) and row.get("file"):
                return True
    except (OSError, UnicodeDecodeError):
        return False
    return False


def should_skip_injection() -> bool:
    """Check if any platform's non-interactive flag is set, or if Trellis
    hooks are explicitly disabled via TRELLIS_HOOKS=0 / TRELLIS_DISABLE_HOOKS=1.
    """
    if os.environ.get("TRELLIS_HOOKS") == "0":
        return True
    if os.environ.get("TRELLIS_DISABLE_HOOKS") == "1":
        return True
    non_interactive_vars = [
        "CLAUDE_NON_INTERACTIVE",
        "QODER_NON_INTERACTIVE",
        "CODEBUDDY_NON_INTERACTIVE",
        "FACTORY_NON_INTERACTIVE",
        "CURSOR_NON_INTERACTIVE",
        "GEMINI_NON_INTERACTIVE",
        "KIRO_NON_INTERACTIVE",
        "COPILOT_NON_INTERACTIVE",
        "TRAE_NON_INTERACTIVE",
    ]
    return any(os.environ.get(var) == "1" for var in non_interactive_vars)


def read_file(path: Path, fallback: str = "") -> str:
    try:
        return path.read_text(encoding="utf-8")
    except (FileNotFoundError, PermissionError):
        return fallback


def _repo_relative(repo_root: Path, path: Path) -> str:
    try:
        return path.relative_to(repo_root).as_posix()
    except ValueError:
        return str(path)


def _run_git(repo_root: Path, args: list[str]) -> str:
    try:
        result = subprocess.run(
            ["git", *args],
            capture_output=True,
            text=True,
            encoding="utf-8",
            errors="replace",
            timeout=3,
            cwd=str(repo_root),
        )
    except (subprocess.TimeoutExpired, FileNotFoundError, PermissionError):
        return ""
    if result.returncode != 0:
        return ""
    return result.stdout.strip()


def _format_git_state(repo_root: Path) -> str:
    branch = _run_git(repo_root, ["branch", "--show-current"]) or "(detached)"
    dirty_lines = [
        line for line in _run_git(repo_root, ["status", "--porcelain"]).splitlines()
        if line.strip()
    ]
    dirty_text = "clean" if not dirty_lines else f"dirty {len(dirty_lines)} paths"
    return f"Git: branch {branch}; {dirty_text}."


def _detect_platform(input_data: dict) -> str | None:
    if isinstance(input_data.get("cursor_version"), str):
        return "cursor"
    env_map = {
        "CLAUDE_PROJECT_DIR": "claude",
        "CURSOR_PROJECT_DIR": "cursor",
        "CODEBUDDY_PROJECT_DIR": "codebuddy",
        "FACTORY_PROJECT_DIR": "droid",
        "GEMINI_PROJECT_DIR": "gemini",
        "QODER_PROJECT_DIR": "qoder",
        "KIRO_PROJECT_DIR": "kiro",
        "COPILOT_PROJECT_DIR": "copilot",
        "TRAE_PROJECT_DIR": "trae",
    }
    for env_name, platform in env_map.items():
        if os.environ.get(env_name):
            return platform
    script_parts = set(Path(sys.argv[0]).parts)
    if ".claude" in script_parts:
        return "claude"
    if ".cursor" in script_parts:
        return "cursor"
    if ".codex" in script_parts:
        return "codex"
    if ".gemini" in script_parts:
        return "gemini"
    if ".qoder" in script_parts:
        return "qoder"
    if ".codebuddy" in script_parts:
        return "codebuddy"
    if ".factory" in script_parts:
        return "droid"
    if ".kiro" in script_parts:
        return "kiro"
    if ".trae" in script_parts:
        return "trae"
    return None


def _resolve_context_key(trellis_dir: Path, input_data: dict) -> str | None:
    scripts_dir = trellis_dir / "scripts"
    if str(scripts_dir) not in sys.path:
        sys.path.insert(0, str(scripts_dir))
    from common.active_task import resolve_context_key  # type: ignore[import-not-found]

    return resolve_context_key(input_data, platform=_detect_platform(input_data))


def _persist_context_key_for_bash(context_key: str | None) -> None:
    """Expose Trellis session identity to later Claude Code Bash commands.

    Claude Code SessionStart hooks can append exports to CLAUDE_ENV_FILE; those
    variables are then available to Bash tools in the same conversation. Without
    this bridge, `task.py start` has hook stdin during SessionStart but no
    session identity when the AI later runs it as a normal shell command.
    """
    if not context_key:
        return
    env_file = os.environ.get("CLAUDE_ENV_FILE")
    if not env_file:
        return
    try:
        with open(env_file, "a", encoding="utf-8") as handle:
            handle.write(f"export TRELLIS_CONTEXT_ID={shlex.quote(context_key)}\n")
    except OSError:
        pass


def _resolve_active_task(trellis_dir: Path, input_data: dict):
    scripts_dir = trellis_dir / "scripts"
    if str(scripts_dir) not in sys.path:
        sys.path.insert(0, str(scripts_dir))
    from common.active_task import resolve_active_task  # type: ignore[import-not-found]

    return resolve_active_task(
        trellis_dir.parent,
        input_data,
        platform=_detect_platform(input_data),
    )


def run_script(script_path: Path, context_key: str | None = None) -> str:
    try:
        if script_path.suffix == ".py":
            # Add PYTHONIOENCODING to force UTF-8 in subprocess
            env = os.environ.copy()
            env["PYTHONIOENCODING"] = "utf-8"
            if context_key:
                env["TRELLIS_CONTEXT_ID"] = context_key
            cmd = [sys.executable, "-W", "ignore", str(script_path)]
        else:
            env = os.environ.copy()
            if context_key:
                env["TRELLIS_CONTEXT_ID"] = context_key
            cmd = [str(script_path)]

        result = subprocess.run(
            cmd,
            capture_output=True,
            text=True,
            encoding="utf-8",
            errors="replace",
            timeout=5,
            cwd=script_path.parent.parent.parent,
            env=env,
        )
        return result.stdout if result.returncode == 0 else "No context available"
    except (subprocess.TimeoutExpired, FileNotFoundError, PermissionError):
        return "No context available"


def _normalize_task_ref(task_ref: str) -> str:
    normalized = task_ref.strip()
    if not normalized:
        return ""

    path_obj = Path(normalized)
    if path_obj.is_absolute():
        return str(path_obj)

    normalized = normalized.replace("\\", "/")
    while normalized.startswith("./"):
        normalized = normalized[2:]

    if normalized.startswith("tasks/"):
        return f".trellis/{normalized}"

    return normalized


def _resolve_task_dir(trellis_dir: Path, task_ref: str) -> Path:
    normalized = _normalize_task_ref(task_ref)
    path_obj = Path(normalized)
    if path_obj.is_absolute():
        return path_obj
    if normalized.startswith(".trellis/"):
        return trellis_dir.parent / path_obj
    return trellis_dir / "tasks" / path_obj


def _get_task_status(trellis_dir: Path, input_data: dict) -> str:
    """Return compact active-task status, artifact presence, and next action."""
    active = _resolve_active_task(trellis_dir, input_data)

    if not active.task_path:
        return (
            "Status: NO ACTIVE TASK\n"
            "Next-Action: Classify the current turn before creating any Trellis task. "
            "Simple conversation / small task asks only whether this turn should create a Trellis task. "
            "Complex task asks whether task creation and planning are allowed."
        )

    task_ref = active.task_path
    task_dir = _resolve_task_dir(trellis_dir, task_ref)
    if active.stale or not task_dir.is_dir():
        return (
            f"Status: STALE POINTER\nTask: {task_ref}\n"
            f"Next-Action: Run `python ./.trellis/scripts/task.py finish` to clear the stale pointer, "
            "then ask the user what to work on next."
        )

    task_json_path = task_dir / "task.json"
    task_data = {}
    if task_json_path.is_file():
        try:
            task_data = json.loads(task_json_path.read_text(encoding="utf-8"))
        except (json.JSONDecodeError, PermissionError):
            pass

    task_title = task_data.get("title", task_ref)
    task_status = task_data.get("status", "unknown")
    artifact_names = ("prd.md", "design.md", "implement.md", "implement.jsonl", "check.jsonl")
    present = [name for name in artifact_names if (task_dir / name).is_file()]
    if (task_dir / "research").is_dir():
        present.append("research/")
    present_line = ", ".join(present) if present else "(none)"

    if task_status == "completed":
        return (
            f"Status: COMPLETED\nTask: {task_title}\n"
            f"Present: {present_line}\n"
            "Next-Action: Run `/trellis:finish-work`. If the working tree is dirty, return to Phase 3.4 first."
        )

    has_prd = (task_dir / "prd.md").is_file()
    has_design = (task_dir / "design.md").is_file()
    has_implement_plan = (task_dir / "implement.md").is_file()
    implement_jsonl = task_dir / "implement.jsonl"
    check_jsonl = task_dir / "check.jsonl"
    jsonl_ready = (
        (not implement_jsonl.is_file() or _has_curated_jsonl_entry(implement_jsonl))
        and (not check_jsonl.is_file() or _has_curated_jsonl_entry(check_jsonl))
    )

    if task_status == "planning" and not has_prd:
        return (
            f"Status: PLANNING\nTask: {task_title}\n"
            f"Present: {present_line}\n"
            "Next-Action: Load `trellis-brainstorm` and write `prd.md`. Stay in planning."
        )

    if task_status == "planning":
        missing_complex = [
            name for name, exists in (
                ("design.md", has_design),
                ("implement.md", has_implement_plan),
            )
            if not exists
        ]
        next_bits: list[str] = []
        if missing_complex:
            next_bits.append(
                "Lightweight task can request start review with PRD-only; "
                f"complex task must add {', '.join(missing_complex)} before start"
            )
        else:
            next_bits.append("Planning artifacts are present; ask for review before `task.py start`")
        if not jsonl_ready:
            next_bits.append("curate `implement.jsonl` and `check.jsonl` before sub-agent mode start")
        return (
            f"Status: PLANNING\nTask: {task_title}\n"
            f"Present: {present_line}\n"
            f"Next-Action: {'; '.join(next_bits)}. Do not enter implementation until the user confirms start."
        )

    return (
        f"Status: {str(task_status).upper()}\nTask: {task_title}\n"
        f"Present: {present_line}\n"
        "Next-Action: Follow the matching per-turn workflow-state. "
        "Implementation/check context order is jsonl entries -> `prd.md` -> `design.md if present` -> `implement.md if present`."
    )


def _load_trellis_config(trellis_dir: Path, input_data: dict) -> tuple:
    """Load Trellis config for session-start decisions.

    Returns:
        (is_mono, packages_dict, spec_scope, task_pkg, default_pkg)
    """
    scripts_dir = trellis_dir / "scripts"
    if str(scripts_dir) not in sys.path:
        sys.path.insert(0, str(scripts_dir))

    try:
        from common.config import get_default_package, get_packages, get_spec_scope, is_monorepo  # type: ignore[import-not-found]
        from common.paths import get_current_task  # type: ignore[import-not-found]

        repo_root = trellis_dir.parent
        is_mono = is_monorepo(repo_root)
        packages = get_packages(repo_root) or {}
        scope = get_spec_scope(repo_root)

        # Get active task's package
        task_pkg = None
        current = get_current_task(
            repo_root,
            input_data,
            platform=_detect_platform(input_data),
        )
        if current:
            task_json = repo_root / current / "task.json"
            if task_json.is_file():
                try:
                    data = json.loads(task_json.read_text(encoding="utf-8"))
                    if isinstance(data, dict):
                        tp = data.get("package")
                        if isinstance(tp, str) and tp:
                            task_pkg = tp
                except (json.JSONDecodeError, OSError):
                    pass

        default_pkg = get_default_package(repo_root)
        return is_mono, packages, scope, task_pkg, default_pkg
    except Exception:
        return False, {}, None, None, None


def _check_legacy_spec(trellis_dir: Path, is_mono: bool, packages: dict) -> str | None:
    """Check for legacy spec directory structure in monorepo.

    Returns warning message if legacy structure detected, None otherwise.
    """
    if not is_mono or not packages:
        return None

    spec_dir = trellis_dir / "spec"
    if not spec_dir.is_dir():
        return None

    # Check for legacy flat spec dirs (spec/backend/, spec/frontend/ with index.md)
    has_legacy = False
    for legacy_name in ("backend", "frontend"):
        legacy_dir = spec_dir / legacy_name
        if legacy_dir.is_dir() and (legacy_dir / "index.md").is_file():
            has_legacy = True
            break

    if not has_legacy:
        return None

    # Check which packages are missing spec/<pkg>/ directory
    missing = [
        name for name in sorted(packages.keys())
        if not (spec_dir / name).is_dir()
    ]

    if not missing:
        return None  # All packages have spec dirs

    if len(missing) == len(packages):
        return (
            f"[!] Legacy spec structure detected: found `spec/backend/` or `spec/frontend/` "
            f"but no package-scoped `spec/<package>/` directories.\n"
            f"Monorepo packages: {', '.join(sorted(packages.keys()))}\n"
            f"Please reorganize: `spec/backend/` -> `spec/<package>/backend/`"
        )
    return (
        f"[!] Partial spec migration detected: packages {', '.join(missing)} "
        f"still missing `spec/<pkg>/` directory.\n"
        f"Please complete migration for all packages."
    )


def _resolve_spec_scope(
    is_mono: bool,
    packages: dict,
    scope,
    task_pkg: str | None,
    default_pkg: str | None,
) -> set | None:
    """Resolve which packages should have their specs injected.

    Returns:
        Set of package names to include, or None for full scan.
    """
    if not is_mono or not packages:
        return None  # Single-repo: full scan

    if scope is None:
        return None  # No scope configured: full scan

    if isinstance(scope, str) and scope == "active_task":
        if task_pkg and task_pkg in packages:
            return {task_pkg}
        if default_pkg and default_pkg in packages:
            return {default_pkg}
        return None  # Fallback to full scan

    if isinstance(scope, list):
        valid = set()
        for entry in scope:
            if entry in packages:
                valid.add(entry)
            else:
                print(
                    f"Warning: spec_scope contains unknown package: {entry}, ignoring",
                    file=sys.stderr,
                )

        if valid:
            # Warn if active task is out of scope
            if task_pkg and task_pkg not in valid:
                print(
                    f"Warning: active task package '{task_pkg}' is out of configured spec_scope",
                    file=sys.stderr,
                )
            return valid

        # All entries invalid: fallback chain
        print(
            "Warning: all spec_scope entries invalid, falling back to task/default/full",
            file=sys.stderr,
        )
        if task_pkg and task_pkg in packages:
            return {task_pkg}
        if default_pkg and default_pkg in packages:
            return {default_pkg}
        return None  # Full scan

    return None  # Unknown scope type: full scan


def _collect_spec_index_paths(trellis_dir: Path, allowed_pkgs: set | None) -> list[str]:
    paths: list[str] = []
    guides_index = trellis_dir / "spec" / "guides" / "index.md"
    if guides_index.is_file():
        paths.append(".trellis/spec/guides/index.md")

    spec_dir = trellis_dir / "spec"
    if not spec_dir.is_dir():
        return paths

    for sub in sorted(spec_dir.iterdir()):
        if not sub.is_dir() or sub.name.startswith(".") or sub.name == "guides":
            continue

        index_file = sub / "index.md"
        if index_file.is_file():
            paths.append(f".trellis/spec/{sub.name}/index.md")
            continue

        if allowed_pkgs is not None and sub.name not in allowed_pkgs:
            continue
        for nested in sorted(sub.iterdir()):
            if not nested.is_dir():
                continue
            nested_index = nested / "index.md"
            if nested_index.is_file():
                paths.append(f".trellis/spec/{sub.name}/{nested.name}/index.md")

    return paths


def _build_compact_current_state(
    trellis_dir: Path,
    input_data: dict,
    spec_index_paths: list[str],
) -> str:
    repo_root = trellis_dir.parent
    lines: list[str] = []

    try:
        from common.paths import get_active_journal_file, get_developer, get_tasks_dir, count_lines  # type: ignore[import-not-found]
        from common.tasks import iter_active_tasks  # type: ignore[import-not-found]
    except Exception:
        get_active_journal_file = None  # type: ignore[assignment]
        get_developer = None  # type: ignore[assignment]
        get_tasks_dir = None  # type: ignore[assignment]
        count_lines = None  # type: ignore[assignment]
        iter_active_tasks = None  # type: ignore[assignment]

    developer = get_developer(repo_root) if get_developer else None
    lines.append(f"Developer: {developer or '(not initialized)'}")
    lines.append(_format_git_state(repo_root))

    active = _resolve_active_task(trellis_dir, input_data)
    if active.task_path:
        task_dir = _resolve_task_dir(trellis_dir, active.task_path)
        status = "unknown"
        task_json = task_dir / "task.json"
        if task_json.is_file():
            try:
                data = json.loads(task_json.read_text(encoding="utf-8"))
                if isinstance(data, dict):
                    status = str(data.get("status") or "unknown")
            except (json.JSONDecodeError, OSError):
                pass
        lines.append(f"Current task: {_repo_relative(repo_root, task_dir)}; status={status}.")
    else:
        lines.append("Current task: none.")

    if get_tasks_dir and iter_active_tasks:
        try:
            task_count = sum(1 for _ in iter_active_tasks(get_tasks_dir(repo_root)))
            lines.append(
                f"Active tasks: {task_count} total. Use `python ./.trellis/scripts/task.py list --mine` only if needed."
            )
        except Exception:
            pass

    if get_active_journal_file and count_lines:
        journal = get_active_journal_file(repo_root)
        if journal:
            lines.append(
                f"Journal: {_repo_relative(repo_root, journal)}, {count_lines(journal)} / 2000 lines."
            )

    if spec_index_paths:
        lines.append(f"Spec indexes: {len(spec_index_paths)} available.")

    return "\n".join(lines)


def _extract_range(content: str, start_header: str, end_header: str) -> str:
    """Extract lines starting at `## start_header` up to (but excluding) `## end_header`.

    Both parameters are full header lines WITHOUT the `## ` prefix (e.g. "Phase Index").
    Returns empty string if start header is not found.
    End header missing → extracts to end of file.
    """
    lines = content.splitlines()
    start: int | None = None
    end: int = len(lines)
    start_match = f"## {start_header}"
    end_match = f"## {end_header}"
    for i, line in enumerate(lines):
        stripped = line.strip()
        if start is None and stripped == start_match:
            start = i
            continue
        if start is not None and stripped == end_match:
            end = i
            break
    if start is None:
        return ""
    return "\n".join(lines[start:end]).rstrip()


_BREADCRUMB_TAG_RE = re.compile(
    r"\[workflow-state:([A-Za-z0-9_-]+)\]\s*\n.*?\n\s*\[/workflow-state:\1\]",
    re.DOTALL,
)


def _strip_breadcrumb_tag_blocks(content: str) -> str:
    """Remove `[workflow-state:STATUS]...[/workflow-state:STATUS]` blocks.

    The tag blocks live inside `## Phase Index` (since v0.5.0-rc.0, when
    they were colocated with their phase summaries) and are consumed by the
    UserPromptSubmit hook (`inject-workflow-state.py`). The session-start
    payload already covers the full step bodies, so re-inlining the
    breadcrumbs here would just duplicate context.
    """
    stripped = _BREADCRUMB_TAG_RE.sub("", content)
    stripped = re.sub(r"<!--.*?-->", "", stripped, flags=re.DOTALL)
    stripped = re.sub(r"^\[(?!/?workflow-state:)/?[^\]\n]+\]\s*\n?", "", stripped, flags=re.MULTILINE)
    return re.sub(r"\n{3,}", "\n\n", stripped).strip()


def _build_workflow_overview(workflow_path: Path) -> str:
    """Inject only the compact Phase Index summary for SessionStart."""
    content = read_file(workflow_path)
    if not content:
        return "No workflow.md found"

    out_lines = [
        "# Development Workflow - Session Summary",
        "Full guide: .trellis/workflow.md. Step detail: `python ./.trellis/scripts/get_context.py --mode phase --step <X.Y>`.",
        "",
    ]

    phases = _extract_range(content, "Phase Index", "Phase 1: Plan")
    if phases:
        out_lines.append(_strip_breadcrumb_tag_blocks(phases).rstrip())

    return "\n".join(out_lines).rstrip()


def main():
    if should_skip_injection():
        sys.exit(0)

    try:
        hook_input = json.loads(sys.stdin.read())
        if not isinstance(hook_input, dict):
            hook_input = {}
    except (json.JSONDecodeError, ValueError):
        hook_input = {}

    # Try platform-specific env vars, hook cwd, fallback to cwd
    project_dir_env_vars = [
        "CLAUDE_PROJECT_DIR",
        "QODER_PROJECT_DIR",
        "CODEBUDDY_PROJECT_DIR",
        "FACTORY_PROJECT_DIR",
        "CURSOR_PROJECT_DIR",
        "GEMINI_PROJECT_DIR",
        "KIRO_PROJECT_DIR",
        "COPILOT_PROJECT_DIR",
        "TRAE_PROJECT_DIR",
    ]
    project_dir = None
    for var in project_dir_env_vars:
        val = os.environ.get(var)
        if val:
            project_dir = Path(_normalize_windows_shell_path(val)).resolve()
            break
    if project_dir is None:
        project_dir = Path(_normalize_windows_shell_path(hook_input.get("cwd", "."))).resolve()

    trellis_dir = project_dir / ".trellis"
    context_key = _resolve_context_key(trellis_dir, hook_input)
    _persist_context_key_for_bash(context_key)

    # Load config for scope filtering and legacy detection
    is_mono, packages, scope_config, task_pkg, default_pkg = _load_trellis_config(
        trellis_dir,
        hook_input,
    )
    allowed_pkgs = _resolve_spec_scope(is_mono, packages, scope_config, task_pkg, default_pkg)

    output = StringIO()

    spec_index_paths = _collect_spec_index_paths(trellis_dir, allowed_pkgs)

    output.write("""<session-context>
Trellis compact SessionStart context. Use it to orient the session; load details on demand.
</session-context>

""")
    output.write(FIRST_REPLY_NOTICE)
    output.write("\n\n")

    # Legacy migration warning
    legacy_warning = _check_legacy_spec(trellis_dir, is_mono, packages)
    if legacy_warning:
        output.write(f"<migration-warning>\n{legacy_warning}\n</migration-warning>\n\n")

    output.write("<current-state>\n")
    output.write(_build_compact_current_state(trellis_dir, hook_input, spec_index_paths))
    output.write("\n</current-state>\n\n")

    output.write("<trellis-workflow>\n")
    output.write(_build_workflow_overview(trellis_dir / "workflow.md"))
    output.write("\n</trellis-workflow>\n\n")

    output.write("<guidelines>\n")
    output.write(
        "Task context order for implementation/check: jsonl entries -> `prd.md` -> "
        "`design.md if present` -> `implement.md if present`. Missing optional artifacts "
        "are skipped for lightweight tasks.\n\n"
    )

    if spec_index_paths:
        output.write("## Available indexes (read on demand)\n")
        for p in spec_index_paths:
            output.write(f"- {p}\n")
        output.write("\n")

    output.write(
        "Discover more via: "
        "`python ./.trellis/scripts/get_context.py --mode packages`\n"
    )
    output.write("</guidelines>\n\n")

    # Check task status and inject structured tag
    task_status = _get_task_status(trellis_dir, hook_input)
    output.write(f"<task-status>\n{task_status}\n</task-status>\n\n")

    output.write("""<ready>
Context loaded. Follow <task-status>. Load workflow/spec/task details only when needed.
</ready>""")

    context_text = output.getvalue()

    # Kiro (CLI trellis agent agentSpawn) adds a hook's stdout directly to the
    # conversation context — no JSON envelope. Emit the bare overview text.
    # Conditionally isolated: all other platforms keep the JSON path below.
    if _detect_platform(hook_input) == "kiro":
        print(context_text, flush=True)
        return

    result = {
        # Claude Code / Qoder / CodeBuddy / Droid / Gemini / Copilot format
        "hookSpecificOutput": {
            "hookEventName": "SessionStart",
            "additionalContext": context_text,
        },
        # Cursor sessionStart format (top-level snake_case per Cursor docs)
        "additional_context": context_text,
    }

    # Output JSON - stdout is already configured for UTF-8
    print(json.dumps(result, ensure_ascii=False), flush=True)


if __name__ == "__main__":
    main()