import re
from typing import Any

from pydantic import ValidationError

from services.agent.errors import AgentSoulLockedError, InvalidComposerConfigError, PlaintextSecretNotAllowedError
from services.agent.prompt_mentions import (
    MAX_MENTIONS_PER_PROMPT,
    NODE_JOB_PROMPT_ALLOWED_KINDS,
    SOUL_PROMPT_ALLOWED_KINDS,
    MentionKind,
    MentionResolver,
    build_node_job_mention_resolver,
    build_soul_mention_resolver,
    find_malformed_mention_markers,
    parse_prompt_mentions,
)
from services.entities.agent_entities import (
    AgentSoulConfig,
    ComposerSavePayload,
    ComposerVariant,
    WorkflowNodeJobConfig,
)

_PLAINTEXT_SECRET_KEYS = {
    "api_key",
    "apikey",
    "authorization",
    "password",
    "secret",
    "secret_key",
}

# Env/secret names become shell ``export`` identifiers in the sandbox bootstrap, so
# they must be valid shell identifiers. Validating here fails fast at composer save
# with a friendly error instead of at run time in the agent backend shell layer.
_SHELL_ENV_NAME_PATTERN = re.compile(r"^[A-Za-z_][A-Za-z0-9_]*$")
_CLI_TOOL_NAME_KEYS = ("name", "tool_name", "label")
_CLI_TOOL_COMMAND_KEYS = ("command", "install_command", "install", "setup_command")
_DENIED_PERMISSION_STATUSES = frozenset({"unauthorized", "denied", "forbidden", "invalid", "unavailable"})
_DANGEROUS_FLAG_KEYS = ("dangerous", "dangerous_command", "requires_confirmation")
_DANGEROUS_ACK_KEYS = (
    "dangerous_acknowledged",
    "dangerous_accepted",
    "risk_accepted",
    "approved",
)


class ComposerConfigValidator:
    @classmethod
    def validate_save_payload(cls, payload: ComposerSavePayload) -> None:
        if payload.variant == ComposerVariant.WORKFLOW and payload.soul_lock.locked and payload.agent_soul is not None:
            raise AgentSoulLockedError()

        if payload.agent_soul is not None:
            cls.validate_agent_soul(payload.agent_soul)
        if payload.node_job is not None:
            cls.validate_node_job(payload.node_job)
        cls._validate_prompt_mentions(payload)

    @classmethod
    def _validate_prompt_mentions(cls, payload: ComposerSavePayload) -> None:
        """ENG-616 §2.4 allowlists + ENG-617 §5.2 human-must-be-referenced.

        Error messages start with a stable code token (``mention_kind_not_allowed``
        / ``mention_limit_exceeded`` / ``human_involvement_not_referenced``) so
        the frontend can switch on it.
        """
        if payload.agent_soul is not None:
            cls._validate_surface_mentions(
                prompt=payload.agent_soul.prompt.system_prompt,
                allowed=SOUL_PROMPT_ALLOWED_KINDS,
                surface="agent soul prompt",
            )
            cls._require_human_mentions(
                prompt=payload.agent_soul.prompt.system_prompt,
                contacts=payload.agent_soul.human.contacts,
                surface="agent soul prompt",
            )
        if payload.node_job is not None:
            cls._validate_surface_mentions(
                prompt=payload.node_job.workflow_prompt,
                allowed=NODE_JOB_PROMPT_ALLOWED_KINDS,
                surface="workflow job prompt",
            )
            cls._require_human_mentions(
                prompt=payload.node_job.workflow_prompt,
                contacts=payload.node_job.human_contacts,
                surface="workflow job prompt",
            )

    @classmethod
    def _validate_surface_mentions(cls, *, prompt: str, allowed: frozenset[MentionKind], surface: str) -> None:
        mentions = parse_prompt_mentions(prompt)
        if len(mentions) > MAX_MENTIONS_PER_PROMPT:
            raise InvalidComposerConfigError(
                f"mention_limit_exceeded: {surface} has {len(mentions)} mentions, "
                f"exceeding the limit of {MAX_MENTIONS_PER_PROMPT}."
            )
        for mention in mentions:
            if mention.kind not in allowed:
                raise InvalidComposerConfigError(
                    f"mention_kind_not_allowed: {surface} cannot reference {mention.kind.value} (id={mention.ref_id})."
                )

    @classmethod
    def _require_human_mentions(cls, *, prompt: str, contacts: list[Any], surface: str) -> None:
        """ENG-617 §5.2 (PRD: human involvement must be slash-referenced or save errors).

        Every configured human contact must appear as ``{{#human:<id>#}}`` in the
        corresponding prompt. A contact matches via any identity alias; contacts
        carrying no identity at all cannot be referenced and are skipped.
        """
        if not contacts:
            return
        mentioned = {mention.ref_id for mention in parse_prompt_mentions(prompt) if mention.kind == MentionKind.HUMAN}
        for contact in contacts:
            aliases = {
                alias
                for alias in (contact.id, contact.contact_id, contact.human_id, contact.email, contact.name)
                if alias
            }
            if not aliases:
                continue
            if aliases.isdisjoint(mentioned):
                display = contact.name or contact.email or contact.id or "human involvement"
                raise InvalidComposerConfigError(
                    f"human_involvement_not_referenced: configured human involvement '{display}' "
                    f"must be referenced in the {surface} via the slash menu."
                )

    @classmethod
    def collect_soft_findings(
        cls,
        payload: ComposerSavePayload,
        *,
        existing_dataset_ids: set[str] | None = None,
    ) -> dict[str, Any]:
        """ENG-617 §5.3/§5.4 soft findings — never block save.

        ``warnings`` carries ``mention_target_missing`` / ``mention_malformed``
        entries; ``knowledge_retrieval_placeholder`` keeps dangling knowledge
        mentions with a placeholder name (0522 consensus) instead of dropping or
        rejecting them. With ``existing_dataset_ids`` provided, configured-but-
        deleted datasets surface as placeholders too.
        """
        warnings: list[dict[str, Any]] = []
        placeholders: list[dict[str, str]] = []

        surfaces: list[tuple[str, str, MentionResolver, frozenset[MentionKind]]] = []
        if payload.agent_soul is not None:
            surfaces.append(
                (
                    "agent_soul",
                    payload.agent_soul.prompt.system_prompt,
                    build_soul_mention_resolver(payload.agent_soul),
                    SOUL_PROMPT_ALLOWED_KINDS,
                )
            )
        if payload.node_job is not None:
            surfaces.append(
                (
                    "node_job",
                    payload.node_job.workflow_prompt,
                    build_node_job_mention_resolver(payload.node_job),
                    NODE_JOB_PROMPT_ALLOWED_KINDS,
                )
            )

        for surface, prompt, resolver, allowed in surfaces:
            for mention in parse_prompt_mentions(prompt):
                if mention.kind not in allowed:
                    continue  # hard-rejected by validate_save_payload
                resolved = resolver(mention)
                if mention.kind == MentionKind.KNOWLEDGE:
                    dangling = resolved is None or (
                        existing_dataset_ids is not None and mention.ref_id not in existing_dataset_ids
                    )
                    if dangling:
                        placeholders.append(
                            {
                                "id": mention.ref_id,
                                "placeholder_name": mention.label or f"Knowledge {mention.ref_id[:8]}",
                            }
                        )
                    continue
                if resolved is None:
                    warnings.append(
                        {
                            "code": "mention_target_missing",
                            "surface": surface,
                            "kind": mention.kind.value,
                            "id": mention.ref_id,
                            "message": f"{mention.kind.value} mention (id={mention.ref_id}) does not match "
                            "any configured item.",
                        }
                    )
            for marker in find_malformed_mention_markers(prompt):
                warnings.append(
                    {
                        "code": "mention_malformed",
                        "surface": surface,
                        "kind": None,
                        "id": None,
                        "message": f"mention-shaped marker {marker!r} is malformed and will be "
                        "degraded to plain text at runtime.",
                    }
                )

        return {"warnings": warnings, "knowledge_retrieval_placeholder": placeholders}

    @classmethod
    def validate_agent_soul(cls, agent_soul: AgentSoulConfig) -> None:
        dumped = agent_soul.model_dump(mode="json")
        cls._reject_plaintext_secrets(dumped, path="agent_soul")
        cls._validate_shell_config(dumped)

    @classmethod
    def validate_node_job(cls, node_job: WorkflowNodeJobConfig) -> None:
        cls._reject_plaintext_secrets(node_job.model_dump(mode="json"), path="node_job")

    @classmethod
    def validate_agent_soul_dict(cls, value: dict[str, Any]) -> AgentSoulConfig:
        try:
            config = AgentSoulConfig.model_validate(value)
        except ValidationError as exc:
            raise InvalidComposerConfigError(str(exc)) from exc
        cls.validate_agent_soul(config)
        return config

    @classmethod
    def validate_node_job_dict(cls, value: dict[str, Any]) -> WorkflowNodeJobConfig:
        try:
            config = WorkflowNodeJobConfig.model_validate(value)
        except ValidationError as exc:
            raise InvalidComposerConfigError(str(exc)) from exc
        cls.validate_node_job(config)
        return config

    @classmethod
    def _validate_shell_config(cls, soul: dict[str, Any]) -> None:
        """Fail fast on shell env/secret/CLI config the sandbox would otherwise reject at run time."""
        env = soul.get("env") or {}
        seen_env_names: set[str] = set()
        for section in ("variables", "secret_refs"):
            entries = env.get(section)
            if not isinstance(entries, list):
                continue
            for entry in entries:
                if not isinstance(entry, dict):
                    continue
                raw_name = entry.get("name")
                if not isinstance(raw_name, str) or not raw_name.strip():
                    # Unnamed draft rows are tolerated; only named entries are bound to the shell.
                    continue
                name = raw_name.strip()
                if not _SHELL_ENV_NAME_PATTERN.fullmatch(name):
                    raise InvalidComposerConfigError(
                        f"env/secret name '{name}' must be a valid shell identifier (^[A-Za-z_][A-Za-z0-9_]*$)."
                    )
                if section == "secret_refs" and cls._permission_denied(entry):
                    raise InvalidComposerConfigError(f"secret reference '{name}' is not authorized for this agent.")
                if name in seen_env_names:
                    raise InvalidComposerConfigError(
                        f"duplicate env/secret name '{name}': environment variables and secret references "
                        "share the shell namespace."
                    )
                seen_env_names.add(name)

        tools = soul.get("tools") or {}
        cli_tools = tools.get("cli_tools")
        if isinstance(cli_tools, list):
            for entry in cli_tools:
                if not isinstance(entry, dict) or entry.get("enabled") is False:
                    continue
                has_name = any(isinstance(entry.get(key), str) and entry[key].strip() for key in _CLI_TOOL_NAME_KEYS)
                has_command = cls._has_install_command(entry)
                if not has_name and not has_command:
                    raise InvalidComposerConfigError("an enabled CLI tool must declare a name or an install command.")
                if cls._permission_denied(entry) or entry.get("pre_authorized") is False:
                    raise InvalidComposerConfigError("an enabled CLI tool is not authorized for runtime bootstrap.")
                if cls._dangerous_without_acknowledgement(entry):
                    raise InvalidComposerConfigError(
                        "a dangerous CLI tool command must be explicitly acknowledged before save."
                    )

    @classmethod
    def _reject_plaintext_secrets(cls, value: Any, *, path: str) -> None:
        if isinstance(value, dict):
            for key, nested in value.items():
                normalized_key = key.lower().replace("-", "_")
                nested_path = f"{path}.{key}"
                if normalized_key in _PLAINTEXT_SECRET_KEYS and isinstance(nested, str) and nested:
                    raise PlaintextSecretNotAllowedError(f"Plaintext secret is not allowed at {nested_path}")
                cls._reject_plaintext_secrets(nested, path=nested_path)
        elif isinstance(value, list):
            for index, nested in enumerate(value):
                cls._reject_plaintext_secrets(nested, path=f"{path}[{index}]")

    @classmethod
    def _has_install_command(cls, entry: dict[str, Any]) -> bool:
        raw_commands = entry.get("install_commands")
        if isinstance(raw_commands, list) and any(
            isinstance(command, str) and command.strip() for command in raw_commands
        ):
            return True
        return any(isinstance(entry.get(key), str) and entry[key].strip() for key in _CLI_TOOL_COMMAND_KEYS)

    @classmethod
    def _permission_denied(cls, entry: dict[str, Any]) -> bool:
        permission = entry.get("permission")
        if isinstance(permission, dict):
            allowed = permission.get("allowed")
            if allowed is False:
                return True
            status = permission.get("status") or permission.get("state")
            if isinstance(status, str) and status in _DENIED_PERMISSION_STATUSES:
                return True

        for key in ("authorization_status", "permission_status", "status"):
            status = entry.get(key)
            if isinstance(status, str) and status in _DENIED_PERMISSION_STATUSES:
                return True
        return False

    @classmethod
    def _dangerous_without_acknowledgement(cls, entry: dict[str, Any]) -> bool:
        dangerous = any(entry.get(key) is True for key in _DANGEROUS_FLAG_KEYS)
        risk_level = entry.get("risk_level")
        if isinstance(risk_level, str) and risk_level == "dangerous":
            dangerous = True
        if not dangerous:
            return False
        return not any(entry.get(key) is True for key in _DANGEROUS_ACK_KEYS)