"""
multi_agent.py — Agentic loop untuk Gemini Claw.

Filosofi inti:
  "Humans set direction; Claw executes and delivers."

Single agent (Executor) yang langsung mengeksekusi permintaan user
menggunakan tools. Tidak ada Architect atau Reviewer.

Urutan konteks setiap turn:
  1. System prompt (dimuat dari system_prompt.md)
  2. History percakapan sebelumnya (user & assistant)
  3. Input user saat ini

Error handling:
  - Output setiap tool diperiksa terhadap pola kegagalan.
  - Jika error terdeteksi, pesan koreksi eksplisit diinjeksikan ke konteks
    sehingga AI WAJIB memperbaiki sebelum lanjut.
  - Jika consecutive error >= MAX_CONSECUTIVE_ERRORS, loop dihentikan paksa.
"""
from __future__ import annotations

import os
import re
from pathlib import Path

from .agent_tools import dispatch, set_workspace
from .gemini_client import GeminiAPIError, call_gemini, DEFAULT_MODEL

MAX_EXEC_TURNS         = 25   # Batas turn per siklus
MAX_CONSECUTIVE_ERRORS = 4    # hentikan paksa jika AI terus gagal tanpa progres

# ── Load system prompt dari file ──────────────────────────────────────────────

_PROMPT_FILE = Path(__file__).parent.parent / "system_prompt.md"


def _load_system_prompt(workspace: Path) -> str:
    """Baca system_prompt.md dan isi placeholder {workspace}."""
    template = _PROMPT_FILE.read_text(encoding="utf-8")
    return template.replace("{workspace}", str(workspace))


# ── Injection anti-halusinasi (sama seperti agent_loop) ──────────────────────

_INJECTION = (
    "[SYSTEM INJECTION — IKUTI TANPA PENGECUALIAN]\n"
    "1. Kamu HANYA menulis balasan kamu sendiri. "
    "DILARANG menulis label seperti 'User:', 'Assistant:', 'History:', "
    "'Agent:', atau melanjutkan percakapan seolah kamu adalah user.\n"
    "2. Mulai responmu dengan token: [start_response]\n"
    "3. Akhiri responmu dengan token: [end_response]\n"
    "4. Jangan menulis apapun setelah [end_response].\n"
    "Sekarang tulis responmu:"
)

_RESPONSE_TOKEN_RE = re.compile(r"\[start_response\]|\[end_response\]", re.IGNORECASE)


# ── TOOL CALL PARSER (format markdown sesuai system_prompt.md) ───────────────
# Format:
#   ```tools_call
#   [nama]
#   <nama_tool>
#   [reason]
#   <alasan>
#   [param]
#   <nilai>
#   [param_multiline]
#   <<EOF
#   baris 1
#   EOF
#   ```

_TOOLS_CALL_BLOCK_RE = re.compile(r"```tools_call\n(.*?)```", re.DOTALL)
_PARAM_KEY_RE        = re.compile(r"^\[(\w+)\]$")

_INT_PARAMS = {"offset", "limit", "timeout", "context_lines"}


def _parse_tools_call_block(block: str) -> dict | None:
    """Parse satu blok tools_call menjadi dict {name, params}."""
    lines  = block.splitlines()
    fields: dict[str, str] = {}
    i = 0
    while i < len(lines):
        key_match = _PARAM_KEY_RE.match(lines[i].strip())
        if key_match:
            key = key_match.group(1)
            i  += 1
            if i >= len(lines):
                break
            if lines[i].strip() == "<<EOF":
                i += 1
                multi: list[str] = []
                while i < len(lines) and lines[i].strip() != "EOF":
                    multi.append(lines[i])
                    i += 1
                fields[key] = "\n".join(multi)
            else:
                fields[key] = lines[i].strip()
        i += 1

    name   = fields.pop("nama", None)
    reason = fields.pop("reason", "") or ""
    if name:
        return {"name": name, "reason": reason, "params": fields}
    return None


def _parse_tool_calls(text: str) -> list[dict]:
    calls = []
    for m in _TOOLS_CALL_BLOCK_RE.finditer(text):
        parsed = _parse_tools_call_block(m.group(1))
        if parsed:
            calls.append(parsed)
    return calls


def _strip_tool_calls(text: str) -> str:
    """Hapus blok tools_call dan token [start/end_response] dari teks."""
    cleaned = _TOOLS_CALL_BLOCK_RE.sub("", text)
    cleaned = _RESPONSE_TOKEN_RE.sub("", cleaned)
    cleaned = re.sub(r"\n{3,}", "\n\n", cleaned)
    return cleaned.strip()


def _render_tool_result(name: str, output: str) -> str:
    return f'\n<tool_result name="{name}">\n{output}\n</tool_result>\n'


def _cast_params(params: dict) -> dict:
    result = {}
    for k, v in params.items():
        if k in _INT_PARAMS:
            try:
                result[k] = int(v)
            except ValueError:
                result[k] = v
        else:
            result[k] = v
    return result


# ── Error detection ───────────────────────────────────────────────────────────

_ERROR_PATTERNS = re.compile(
    r"(\[Error\]"
    r"|\[exit code:\s*[^0]\d*\]"
    r"|Traceback \(most recent"
    r"|FileNotFoundError"
    r"|PermissionError"
    r"|SyntaxError"
    r"|tidak ditemukan"
    r"|String tidak ditemukan"
    r"|String ditemukan \d+ kali"
    r"|Gagal)",
    re.IGNORECASE,
)


def _is_error_output(output: str) -> bool:
    """Kembalikan True jika output tool mengindikasikan kegagalan."""
    return bool(_ERROR_PATTERNS.search(output))


def _build_error_correction_message(tool_name: str, output: str) -> str:
    """
    Buat pesan injeksi yang memaksa AI fokus memperbaiki error
    sebelum melanjutkan ke langkah berikutnya.
    """
    return (
        f"[SYSTEM — ERROR DETECTED]\n"
        f"Tool `{tool_name}` GAGAL dengan pesan:\n\n"
        f"{output.strip()}\n\n"
        f"INSTRUKSI WAJIB:\n"
        f"1. Analisis pesan error di atas dengan seksama.\n"
        f"2. JANGAN lanjut ke langkah berikutnya sebelum error ini diperbaiki.\n"
        f"3. Jika error berasal dari `edit_file`: baca ulang file terlebih dahulu\n"
        f"   dengan `read_file` untuk mendapatkan konten terkini, lalu ulangi edit\n"
        f"   dengan `old_string` yang PERSIS sesuai isi file.\n"
        f"4. Jika error berasal dari `bash`: periksa perintah, path, dan dependensi.\n"
        f"5. Setelah berhasil memperbaiki, lanjutkan rencana semula."
    )




# ── AGENT LOOP ────────────────────────────────────────────────────────────────

class MultiAgentLoop:
    """
    Executor agent loop untuk Gemini Claw.

    Urutan konteks setiap API call:
        [system prompt] → [history user & assistant] → [input user]

    History hanya hidup selama sesi loop; input baru memulai history baru
    jika conversation dikosongkan dari luar.
    """

    def __init__(self, model: str = DEFAULT_MODEL, workspace: str | Path | None = None):
        self.model     = model
        self.workspace = Path(workspace) if workspace else Path("/tmp/workspace")
        self.workspace.mkdir(parents=True, exist_ok=True)

    def _build_prompt(self, conversation: list[dict], system: str) -> str:
        """
        Susun prompt:
          [system prompt] → [20 history terakhir] → [input user saat ini] → [injection]
        """
        lines = []

        # ── 1. System prompt ──────────────────────────────────────────────────
        lines.append(system)
        lines.append("")

        # ── 2. History (20 pesan, kecuali input user saat ini) ───────────────
        history = conversation[:-1]
        for msg in history[-20:]:
            role = "User" if msg["role"] == "user" else "Assistant"
            lines.append(f"{role}: {msg['content']}")

        if len(history) > 0:
            lines.append("")

        # ── 3. Input user saat ini ────────────────────────────────────────────
        current_input = conversation[-1]["content"] if conversation else ""
        lines.append(f"User: {current_input}")
        lines.append("")

        # ── 4. Injection anti-halusinasi ──────────────────────────────────────
        lines.append(_INJECTION)

        return "\n".join(lines)

    def run(
        self,
        user_input:     str,
        conversation:   list[dict],
        on_phase:       callable = None,
        on_text:        callable = None,
        on_tool_start:  callable = None,
        on_tool_result: callable = None,
    ) -> tuple[str, list[dict]]:
        """
        Jalankan executor loop untuk satu giliran user.

        Returns: (final_reply_text, updated_conversation)
        """
        if on_phase:
            on_phase("executor", "⚙️ Mengerjakan tugas...")

        set_workspace(self.workspace)
        system = _load_system_prompt(self.workspace)

        # Mulai dari snapshot history, tambah pesan user saat ini
        conv = list(conversation)
        conv.append({"role": "user", "content": user_input})

        final_text         = ""
        turn               = 0
        consecutive_errors = 0   # jumlah error beruntun tanpa progres

        while turn < MAX_EXEC_TURNS:
            turn += 1

            full_prompt = self._build_prompt(conv, system)

            try:
                raw_reply = call_gemini(full_prompt, model=self.model)
            except GeminiAPIError as e:
                err = f"[Error API] {e}"
                if on_text:
                    on_text(err)
                return err, conv

            tool_calls   = _parse_tool_calls(raw_reply)
            visible_text = _strip_tool_calls(raw_reply)

            if visible_text and on_text:
                on_text(visible_text)

            if not tool_calls:
                # Tidak ada tool call → selesai
                conv.append({"role": "assistant", "content": raw_reply})
                final_text = visible_text
                break

            # ── Eksekusi tool calls ───────────────────────────────────────────
            tool_results_block = ""
            turn_had_error     = False

            for tc in tool_calls:
                name   = tc["name"]
                reason = tc.get("reason", "")
                params = _cast_params(tc["params"])

                if on_tool_start:
                    on_tool_start(name, params, reason)

                output = dispatch(name, params)

                if on_tool_result:
                    on_tool_result(name, output)

                if _is_error_output(output):
                    # Ganti output biasa dengan pesan koreksi yang eksplisit
                    error_msg           = _build_error_correction_message(name, output)
                    tool_results_block += _render_tool_result(name, error_msg)
                    turn_had_error      = True
                else:
                    tool_results_block += _render_tool_result(name, output)

            # ── Update consecutive error counter ──────────────────────────────
            if turn_had_error:
                consecutive_errors += 1
            else:
                consecutive_errors = 0   # reset jika ada turn bersih

            if consecutive_errors >= MAX_CONSECUTIVE_ERRORS:
                abort_msg = (
                    f"[SYSTEM — LOOP DIHENTIKAN]\n"
                    f"AI telah gagal {consecutive_errors} kali berturut-turut tanpa memperbaiki "
                    f"error. Harap periksa error terakhir secara manual."
                )
                if on_text:
                    on_text(abort_msg)
                conv.append({"role": "assistant", "content": raw_reply})
                return abort_msg, conv

            conv.append({"role": "assistant", "content": raw_reply})
            conv.append({"role": "user",      "content": tool_results_block.strip()})

        else:
            final_text = "[Batas maksimum turn tercapai]"

        return final_text, conv