"""Code Simplification Workflow

Reduces unnecessary complexity in code. Inspired by Boris
Cherny's observation that Claude tends to over-engineer:
too many abstractions, unnecessary classes, premature
optimization, over-configurable interfaces.

Delegates all analysis to three Agent SDK subagents
(complexity-scanner, simplification-designer, safety-reviewer)
and synthesizes their findings into a unified WorkflowResult.

Copyright 2025 Smart-AI-Memory
Licensed under the Apache License, Version 2.0
"""

from __future__ import annotations

import logging
from datetime import datetime
from pathlib import Path
from typing import Any

import claude_agent_sdk

from .agent_sdk_adapter import (
    AgentRunResult,
    AgentSDKResultAdapter,
    build_result_text,
    collect_agent_output,
    get_max_budget_usd,
    get_subagent_model,
)
from .base import BaseWorkflow, ModelTier
from .data_classes import CostReport, WorkflowResult, WorkflowStage

logger = logging.getLogger(__name__)

# Categories the crew should focus on for simplification
SIMPLIFY_FOCUS_AREAS = [
    "simplify",
    "consolidate_conditional",
    "inline",
    "dead_code",
]

# Simplify-related RefactoringCategory values to keep from crew results
SIMPLIFY_CATEGORIES = {
    "simplify",
    "consolidate_conditional",
    "inline",
    "dead_code",
}

_DEPTH_MAX_TURNS: dict[str, int] = {
    "quick": 10,
    "standard": 20,
    "deep": 40,
}

_SUBAGENT_NAMES = [
    "complexity-scanner",
    "simplification-designer",
    "safety-reviewer",
]

_SYSTEM_PROMPT = """\
You are a senior code simplification orchestrator. You coordinate three \
specialized subagents to produce a unified simplification report. \
Be thorough but concise. Cite file paths and line numbers when possible.\
"""

_TASK_PROMPT_TEMPLATE = """\
Analyze the codebase at {path} using the three specialized subagents \
below. Each subagent should focus on its domain and report findings \
as structured markdown.

After all subagents finish, synthesize their findings into a single \
report with these sections:

## Summary
Overall complexity score (0-100) and a 2-3 sentence executive summary \
of simplification opportunities.

## Complexity
Findings from the complexity scanner — deep nesting, long functions, \
unnecessary abstractions, dead code paths, and over-engineered patterns.

## Refactoring
Proposed simplifications from the simplification designer — flattened \
conditionals, inlined helpers, reduced class hierarchies, and removed \
dead code.

## Suggestions
Safety-reviewed actionable next steps ordered by impact. Each suggestion \
should note whether it is safe to apply automatically or requires manual \
review.\
"""


class SimplifyCodeWorkflow(BaseWorkflow):
    """Simplify over-engineered code with Agent SDK subagents.

    Delegates all analysis to three Agent SDK subagents rather
    than using the mixin stage system. Each subagent focuses on
    a specific simplification domain (complexity scanning,
    simplification design, safety review). The orchestrator
    synthesizes findings into a unified report.

    Boris's insight: Claude over-engineers. This workflow
    counteracts that by flattening nesting, inlining trivial
    helpers, removing dead code, and reducing abstractions.

    Usage::

        workflow = SimplifyCodeWorkflow()
        result = await workflow.execute(path="src/", depth="standard")
    """

    name = "simplify-code"
    description = "Simplify over-engineered code with Agent SDK subagents"
    stages = ["agent-simplify"]
    tier_map = {"agent-simplify": ModelTier.CAPABLE}

    async def execute(self, **kwargs: Any) -> WorkflowResult:
        """Execute the Agent SDK code simplification.

        Args:
            **kwargs: Keyword arguments.
                path (str): Required. Directory or file to simplify.
                depth (str): Analysis depth — "quick", "standard",
                    or "deep". Defaults to "standard".

        Returns:
            WorkflowResult with findings, suggestions, and metadata.
        """
        path_arg: str = kwargs.get("path", "")
        depth: str = kwargs.get("depth", "standard")

        if not path_arg:
            return self._error_result("path argument is required")

        resolved_path = str(Path(path_arg).resolve())
        max_turns = _DEPTH_MAX_TURNS.get(depth, 20)

        started_at = datetime.now()

        try:
            run_result = await self._run_agent_simplify(resolved_path, max_turns, depth)

            completed_at = datetime.now()

            return AgentSDKResultAdapter.from_agent_output(
                result_text=run_result.result_text,
                subagent_names=_SUBAGENT_NAMES,
                started_at=started_at,
                completed_at=completed_at,
                metadata={
                    "path": resolved_path,
                    "depth": depth,
                    "max_turns": max_turns,
                },
                agent_run_result=run_result,
            )

        except ImportError as exc:
            logger.error("Agent SDK import failed: %s", exc)
            return self._error_result(f"Agent SDK unavailable: {exc}")
        except (ConnectionError, TimeoutError) as exc:
            logger.error("Agent SDK network error: %s", exc)
            return self._error_result(f"Agent SDK connection failed: {exc}")
        except Exception as exc:  # noqa: BLE001
            # INTENTIONAL: Catch-all for unknown SDK errors to return
            # a structured WorkflowResult rather than crashing.
            logger.exception("Agent SDK code simplification failed: %s", type(exc).__name__)
            return self._error_result(f"Agent SDK error: {type(exc).__name__}: {exc}")

    async def _run_agent_simplify(
        self, resolved_path: str, max_turns: int, depth: str = "standard"
    ) -> AgentRunResult:
        """Run the Agent SDK simplification and return result text.

        Args:
            resolved_path: Absolute path to analyze.
            max_turns: Maximum agent turns.

        Returns:
            AgentRunResult with findings and SDK metadata.
        """
        assistant_parts: list[str] = []
        result_parts: list[str] = []
        run_result = AgentRunResult(result_text="No results returned.")
        async for message in claude_agent_sdk.query(
            prompt=_TASK_PROMPT_TEMPLATE.format(path=resolved_path),
            options=claude_agent_sdk.ClaudeAgentOptions(
                system_prompt=_SYSTEM_PROMPT,
                cwd=resolved_path,
                max_budget_usd=get_max_budget_usd(depth),
                allowed_tools=["Read", "Glob", "Grep", "Agent"],
                permission_mode="default",
                max_turns=max_turns,
                agents={
                    "complexity-scanner": claude_agent_sdk.AgentDefinition(
                        description="Complexity scanner that finds overly complex code.",
                        prompt=(
                            "You are a complexity scanner. Focus on: "
                            "deep nesting (3+ levels), long functions "
                            "(50+ lines), unnecessary abstractions, "
                            "dead code paths, and over-engineered "
                            "patterns. Report each finding with file "
                            "path, line number, complexity metric, and "
                            "why it should be simplified."
                        ),
                        tools=["Read", "Glob", "Grep"],
                        model=get_subagent_model("complexity-scanner"),
                    ),
                    "simplification-designer": claude_agent_sdk.AgentDefinition(
                        description=(
                            "Simplification designer that proposes refactoring approaches."
                        ),
                        prompt=(
                            "You are a simplification designer. For "
                            "each complexity finding, design a concrete "
                            "simplification approach: flatten nested "
                            "conditionals with early returns, inline "
                            "trivial helper functions used only once, "
                            "reduce class hierarchies when a function "
                            "suffices, and remove dead code. Show "
                            "before/after examples."
                        ),
                        tools=["Read", "Glob", "Grep"],
                        model=get_subagent_model("simplification-designer"),
                    ),
                    "safety-reviewer": claude_agent_sdk.AgentDefinition(
                        description=(
                            "Safety reviewer that verifies simplifications" " won't break behavior."
                        ),
                        prompt=(
                            "You are a safety reviewer. For each "
                            "proposed simplification, verify it does "
                            "not break existing behavior, public APIs, "
                            "or tests. Check for side effects, changed "
                            "return types, removed error handling, and "
                            "altered control flow. Flag any risky "
                            "changes that need manual review."
                        ),
                        tools=["Read", "Glob", "Grep"],
                        model=get_subagent_model("safety-reviewer"),
                    ),
                },
            ),
        ):
            sdk_result = collect_agent_output(message, assistant_parts, result_parts)
            if sdk_result is not None:
                run_result = sdk_result
        run_result.result_text = build_result_text(assistant_parts, result_parts)
        return run_result

    def _error_result(self, message: str) -> WorkflowResult:
        """Build a failed WorkflowResult with the given error message.

        Args:
            message: Human-readable error description.

        Returns:
            WorkflowResult with success=False.
        """
        now = datetime.now()
        return WorkflowResult(
            success=False,
            stages=[
                WorkflowStage(
                    name="agent-simplify",
                    tier=ModelTier.CAPABLE,
                    description="Agent SDK code simplification",
                ),
            ],
            final_output=None,
            cost_report=CostReport(
                total_cost=0.0,
                baseline_cost=0.0,
                savings=0.0,
                savings_percent=0.0,
            ),
            started_at=now,
            completed_at=now,
            total_duration_ms=0,
            provider="anthropic",
            error=message,
        )
