"""Sanctioned author issue worktree bootstrap for allocated issues (#850).

Bootstraps an allocated author branch, canonical worktree under ``branches/``,
worktree registration, issue lock, and lease/assignment binding without
caller-side Git, Bash, or helper scripts.

Features:
1. Durable phase journal with read-after-write evidence for every phase.
2. Idempotent replay handling via idempotency keys.
3. Authoritative expected-base / concurrency-pin validation.
4. Typed stale-pin refusal without silent rebasing or repointing.
5. Canonical branches-root enforcement (path MUST be inside branches/).
6. Preexisting work preservation (dirty tracked/untracked check, foreign ownership refusal).
7. Compensating recovery limited strictly to artifacts created by this transition.
8. Satisfiable exact_next_action for MCP scheduled workers.
"""

from __future__ import annotations

import json
import os
import shutil
import subprocess
from typing import Any, Mapping

import author_mutation_worktree
import issue_lock_store
import issue_lock_worktree
import lease_lifecycle
from reviewer_worktree import parse_dirty_tracked_files
import task_capability_map

BOOTSTRAP_TASKS = frozenset(
    {
        "bootstrap_author_issue_worktree",
        "gitea_bootstrap_author_issue_worktree",
    }
)

PHASE_1_REQUEST_ACCEPTED = "1_request_accepted"
PHASE_2_BRANCH_CONFIRMED = "2_branch_confirmed"
PHASE_3_PATH_RESERVED = "3_path_reserved"
PHASE_4_WORKTREE_CONFIRMED = "4_worktree_confirmed"
PHASE_5_REGISTRATION_VERIFIED = "5_registration_verified"
PHASE_6_STATE_ESTABLISHED = "6_state_established"
PHASE_7_TRANSITION_COMPLETED = "7_transition_completed"
PHASE_COMPENSATING_RECOVERY = "compensating_recovery"

JOURNAL_DIR_NAME = "bootstrap-journals"


def is_author_issue_bootstrap_task(task: str | None) -> bool:
    """True when *task* is the author issue worktree bootstrap task."""
    return (task or "").strip() in BOOTSTRAP_TASKS


def get_journal_dir(override: str | None = None) -> str:
    """Return the root directory for durable bootstrap phase journals."""
    if override:
        path = override
    elif os.environ.get("GITEA_BOOTSTRAP_JOURNAL_DIR"):
        path = os.environ["GITEA_BOOTSTRAP_JOURNAL_DIR"]
    else:
        cache_dir = os.path.expanduser("~/.cache/gitea-tools")
        path = os.path.join(cache_dir, JOURNAL_DIR_NAME)
    os.makedirs(path, exist_ok=True)
    return path


def _journal_file_path(idempotency_key: str, journal_dir: str | None = None) -> str:
    safe_key = "".join(
        c if c.isalnum() or c in ("-", "_", ".") else "_"
        for c in idempotency_key
    )
    return os.path.join(get_journal_dir(journal_dir), f"{safe_key}.json")


def load_phase_journal(
    idempotency_key: str, journal_dir: str | None = None
) -> dict[str, Any] | None:
    """Load a durable phase journal if it exists."""
    path = _journal_file_path(idempotency_key, journal_dir=journal_dir)
    if not os.path.isfile(path):
        return None
    try:
        with open(path, "r", encoding="utf-8") as f:
            return json.load(f)
    except Exception:
        return None


def save_phase_journal(
    journal: dict[str, Any], journal_dir: str | None = None
) -> None:
    """Persist a durable phase journal with write-through file sync."""
    key = journal["idempotency_key"]
    path = _journal_file_path(key, journal_dir=journal_dir)
    tmp_path = f"{path}.tmp.{os.getpid()}"
    with open(tmp_path, "w", encoding="utf-8") as f:
        json.dump(journal, f, indent=2, sort_keys=True)
    os.replace(tmp_path, path)


def derive_default_idempotency_key(
    remote: str,
    org: str | None,
    repo: str | None,
    issue_number: int,
    assignment_id: str | None = None,
    lease_id: str | None = None,
) -> str:
    parts = [
        "bootstrap",
        (remote or "prgs").strip(),
        (org or "Scaled-Tech-Consulting").strip(),
        (repo or "Gitea-Tools").strip(),
        f"issue-{issue_number}",
    ]
    if assignment_id:
        parts.append(assignment_id.strip())
    if lease_id:
        parts.append(lease_id.strip())
    return ":".join(parts)


def run_compensating_recovery(
    journal: dict[str, Any],
    canonical_repo_root: str,
) -> dict[str, Any]:
    """Execute compensating recovery for artifacts created by this transition only."""
    artifacts = journal.get("artifacts_created") or {}
    rolled_back: list[str] = []
    worktree_path = journal.get("worktree_path")
    branch_name = journal.get("branch_name")

    if (
        artifacts.get("worktree_registered") or artifacts.get("worktree_dir_created")
    ) and worktree_path:
        if os.path.exists(worktree_path):
            try:
                subprocess.run(
                    [
                        "git",
                        "-C",
                        canonical_repo_root,
                        "worktree",
                        "remove",
                        "--force",
                        worktree_path,
                    ],
                    capture_output=True,
                    text=True,
                    check=False,
                )
            except Exception:
                pass
            if os.path.exists(worktree_path):
                shutil.rmtree(worktree_path, ignore_errors=True)
            try:
                subprocess.run(
                    ["git", "-C", canonical_repo_root, "worktree", "prune"],
                    capture_output=True,
                    text=True,
                    check=False,
                )
            except Exception:
                pass
            rolled_back.append(f"worktree_path:{worktree_path}")

    if artifacts.get("branch_created") and branch_name:
        try:
            res = subprocess.run(
                [
                    "git",
                    "-C",
                    canonical_repo_root,
                    "rev-parse",
                    "--verify",
                    branch_name,
                ],
                capture_output=True,
                text=True,
                check=False,
            )
            if res.returncode == 0:
                subprocess.run(
                    [
                        "git",
                        "-C",
                        canonical_repo_root,
                        "branch",
                        "-D",
                        branch_name,
                    ],
                    capture_output=True,
                    text=True,
                    check=False,
                )
                rolled_back.append(f"branch:{branch_name}")
        except Exception:
            pass

    recovery_info = {
        "executed": True,
        "rolled_back": rolled_back,
        "reason": journal.get("failure_reason"),
    }
    journal["compensating_recovery"] = recovery_info
    journal["current_phase"] = PHASE_COMPENSATING_RECOVERY
    save_phase_journal(journal)
    return recovery_info


def assess_author_issue_bootstrap(
    *,
    workspace_path: str,
    canonical_repo_root: str,
    current_branch: str | None = None,
    head_sha: str | None = None,
    porcelain_status: str = "",
    remote_master_sha: str | None = None,
    remote_master_sha_error: str | None = None,
    task: str | None = None,
) -> dict[str, Any]:
    """Assess whether author issue worktree bootstrap may proceed from control or worktree root."""
    root = os.path.realpath(canonical_repo_root or "")
    workspace = os.path.realpath(workspace_path or root or ".")
    branch = (current_branch or "").strip()
    dirty = parse_dirty_tracked_files(porcelain_status or "")
    under_branches = (
        author_mutation_worktree.is_path_under_branches(workspace, root)
        if root
        else False
    )

    if not is_author_issue_bootstrap_task(task):
        return {
            "not_applicable": True,
            "allowed": False,
            "block": False,
            "proven": False,
            "reasons": ["task is not author_issue_bootstrap"],
        }

    if under_branches:
        return {
            "not_applicable": False,
            "allowed": True,
            "block": False,
            "proven": True,
            "bootstrap_path": "existing_branches_worktree",
            "reasons": [
                "workspace is already a registered worktree under branches/"
            ],
        }

    reasons: list[str] = []
    if workspace != root:
        reasons.append(
            "bootstrap requires workspace to be canonical control checkout or branches/ worktree"
        )
    if branch not in author_mutation_worktree.BASE_BRANCHES:
        reasons.append(
            f"control checkout branch '{branch}' is not an accepted base branch "
            f"({', '.join(sorted(author_mutation_worktree.BASE_BRANCHES))})"
        )
    if dirty:
        reasons.append(
            f"control checkout has tracked local edits: {', '.join(dirty[:5])}"
        )

    if remote_master_sha_error:
        reasons.append(
            f"could not verify live master tip: {remote_master_sha_error}"
        )
    elif remote_master_sha and head_sha:
        h = head_sha.strip().lower()
        rm = remote_master_sha.strip().lower()
        if h != rm:
            reasons.append(
                f"control checkout HEAD ({h[:12]}) != live master tip ({rm[:12]})"
            )

    if reasons:
        return {
            "not_applicable": False,
            "allowed": False,
            "block": True,
            "proven": False,
            "reasons": reasons,
        }

    return {
        "not_applicable": False,
        "allowed": True,
        "block": False,
        "proven": True,
        "bootstrap_path": "clean_canonical_control_checkout",
        "reasons": [
            "control checkout is clean on accepted base branch matching live master"
        ],
    }


def bootstrap_author_issue_worktree(
    *,
    issue_number: int,
    canonical_repo_root: str,
    assignment_id: str | None = None,
    lease_id: str | None = None,
    expected_base_sha: str | None = None,
    branch_name: str | None = None,
    worktree_path: str | None = None,
    idempotency_key: str | None = None,
    remote: str = "prgs",
    host: str | None = None,
    org: str | None = "Scaled-Tech-Consulting",
    repo: str | None = "Gitea-Tools",
    active_identity: str | None = "jcwalker3",
    active_profile: str | None = "prgs-author",
    owner_session: str | None = None,
    lock_dir: str | None = None,
    dry_run: bool = False,
) -> dict[str, Any]:
    """Execute the sanctioned author issue worktree bootstrap transition."""
    root = os.path.realpath(canonical_repo_root)

    # Derive standard inputs
    expected_pattern = f"issue-{issue_number}"
    target_branch = (branch_name or "").strip()
    if not target_branch:
        target_branch = f"fix/issue-{issue_number}-native-mcp-bootstrap"
    elif expected_pattern not in target_branch:
        return {
            "success": False,
            "reason_code": "invalid_branch_name",
            "message": (
                f"Branch name '{target_branch}' must contain issue pattern '{expected_pattern}'"
            ),
            "exact_next_action": (
                f"Supply a branch_name containing '{expected_pattern}', e.g., 'fix/issue-{issue_number}-...'"
            ),
        }

    worktree_name = target_branch.replace("/", "-")
    target_worktree = (worktree_path or "").strip()
    if not target_worktree:
        target_worktree = os.path.join(root, "branches", worktree_name)
    target_worktree = os.path.realpath(os.path.abspath(target_worktree))

    key = (idempotency_key or "").strip()
    if not key:
        key = derive_default_idempotency_key(
            remote=remote,
            org=org,
            repo=repo,
            issue_number=issue_number,
            assignment_id=assignment_id,
            lease_id=lease_id,
        )

    # Idempotency check
    existing = load_phase_journal(key)
    if existing and existing.get("completed"):
        if (
            existing.get("issue_number") == issue_number
            and existing.get("branch_name") == target_branch
            and os.path.realpath(existing.get("worktree_path", ""))
            == target_worktree
        ):
            return {
                "success": True,
                "replayed": True,
                "message": (
                    f"Idempotent replay: worktree for issue #{issue_number} already bootstrapped at {target_worktree}"
                ),
                "issue_number": issue_number,
                "branch_name": target_branch,
                "worktree_path": target_worktree,
                "base_sha": existing.get("resolved_base_sha"),
                "lease_id": existing.get("lease_id"),
                "assignment_id": existing.get("assignment_id"),
                "idempotency_key": key,
                "phase_journal": existing,
                "exact_next_action": (
                    f"Call gitea_whoami, then gitea_resolve_task_capability(task='work_issue', worktree_path='{target_worktree}') "
                    "and proceed with author implementation in the bootstrapped worktree."
                ),
            }
        else:
            return {
                "success": False,
                "reason_code": "incompatible_idempotency_replay",
                "message": (
                    f"Idempotency key '{key}' already exists with incompatible parameters "
                    f"(stored: {existing.get('branch_name')}, {existing.get('worktree_path')}; "
                    f"requested: {target_branch}, {target_worktree})"
                ),
                "exact_next_action": (
                    "Supply a unique idempotency_key or pass compatible parameters."
                ),
            }

    # Initialize Phase Journal
    journal = existing or {
        "idempotency_key": key,
        "issue_number": issue_number,
        "assignment_id": assignment_id,
        "lease_id": lease_id,
        "expected_base_sha": expected_base_sha,
        "resolved_base_sha": None,
        "branch_name": target_branch,
        "worktree_path": target_worktree,
        "active_identity": active_identity,
        "active_profile": active_profile,
        "owner_session": owner_session,
        "remote": remote,
        "org": org,
        "repo": repo,
        "phases": {},
        "artifacts_created": {
            "branch_created": False,
            "worktree_dir_created": False,
            "worktree_registered": False,
            "lock_created": False,
        },
        "current_phase": PHASE_1_REQUEST_ACCEPTED,
        "completed": False,
    }

    # Fetch current live master SHA
    try:
        rev_res = subprocess.run(
            ["git", "-C", root, "rev-parse", "HEAD"],
            capture_output=True,
            text=True,
            check=True,
        )
        live_master_sha = rev_res.stdout.strip()
    except Exception as exc:
        return {
            "success": False,
            "reason_code": "git_rev_parse_failed",
            "message": f"Could not determine repository HEAD: {exc}",
            "exact_next_action": "Verify repository git state and retry.",
        }

    # Phase 1: REQUEST_ACCEPTED & Concurrency Pin Check
    if expected_base_sha:
        exp_norm = expected_base_sha.strip().lower()
        live_norm = live_master_sha.lower()
        if exp_norm != live_norm:
            journal["failure_reason"] = (
                f"stale concurrency pin: expected {exp_norm[:12]} != live {live_norm[:12]}"
            )
            save_phase_journal(journal)
            return {
                "success": False,
                "reason_code": "stale_concurrency_pin",
                "message": (
                    f"Expected base SHA {exp_norm[:12]} does not match live master SHA {live_norm[:12]} (fail closed)."
                ),
                "expected_base_sha": expected_base_sha,
                "live_master_sha": live_master_sha,
                "exact_next_action": (
                    "Re-evaluate assignment against current live master SHA and retry with updated expected_base_sha."
                ),
            }

    journal["resolved_base_sha"] = live_master_sha
    journal["phases"][PHASE_1_REQUEST_ACCEPTED] = {
        "status": "completed",
        "live_master_sha": live_master_sha,
        "expected_base_sha": expected_base_sha,
    }
    journal["current_phase"] = PHASE_2_BRANCH_CONFIRMED
    save_phase_journal(journal)

    if dry_run:
        return {
            "success": True,
            "dry_run": True,
            "message": f"Dry-run: validated bootstrap intent for issue #{issue_number}",
            "issue_number": issue_number,
            "branch_name": target_branch,
            "worktree_path": target_worktree,
            "base_sha": live_master_sha,
            "phase_journal": journal,
            "exact_next_action": "Run without dry_run=True to execute bootstrap.",
        }

    # Phase 2: BRANCH_CONFIRMED
    branch_check = subprocess.run(
        ["git", "-C", root, "rev-parse", "--verify", target_branch],
        capture_output=True,
        text=True,
        check=False,
    )
    if branch_check.returncode == 0:
        branch_head = branch_check.stdout.strip()
        # Verify branch head descends from base
        anc_check = subprocess.run(
            [
                "git",
                "-C",
                root,
                "merge-base",
                "--is-ancestor",
                live_master_sha,
                branch_head,
            ],
            capture_output=True,
            text=True,
            check=False,
        )
        if anc_check.returncode != 0 and branch_head.lower() != live_master_sha.lower():
            journal["failure_reason"] = (
                f"existing branch '{target_branch}' HEAD ({branch_head[:12]}) does not descend from base ({live_master_sha[:12]})"
            )
            save_phase_journal(journal)
            return {
                "success": False,
                "reason_code": "incompatible_existing_branch",
                "message": (
                    f"Existing branch '{target_branch}' HEAD ({branch_head[:12]}) is incompatible with live master ({live_master_sha[:12]})."
                ),
                "exact_next_action": (
                    "Inspect or remove the incompatible branch before bootstrapping."
                ),
            }
        journal["artifacts_created"]["branch_created"] = False
    else:
        # Create branch
        create_res = subprocess.run(
            ["git", "-C", root, "branch", target_branch, live_master_sha],
            capture_output=True,
            text=True,
            check=False,
        )
        if create_res.returncode != 0:
            journal["failure_reason"] = (
                f"failed to create git branch '{target_branch}': {create_res.stderr.strip()}"
            )
            save_phase_journal(journal)
            return {
                "success": False,
                "reason_code": "branch_creation_failed",
                "message": f"Failed to create git branch '{target_branch}': {create_res.stderr.strip()}",
                "exact_next_action": "Verify branch availability and retry.",
            }
        journal["artifacts_created"]["branch_created"] = True

    journal["phases"][PHASE_2_BRANCH_CONFIRMED] = {
        "status": "completed",
        "branch_name": target_branch,
        "created": journal["artifacts_created"]["branch_created"],
    }
    journal["current_phase"] = PHASE_3_PATH_RESERVED
    save_phase_journal(journal)

    # Phase 3: PATH_RESERVED
    if not author_mutation_worktree.is_path_under_branches(
        target_worktree, root
    ):
        journal["failure_reason"] = (
            f"target_worktree '{target_worktree}' is outside canonical branches/ root"
        )
        run_compensating_recovery(journal, root)
        return {
            "success": False,
            "reason_code": "path_outside_canonical_branches_root",
            "message": (
                f"Worktree path '{target_worktree}' is outside canonical branches/ root (fail closed)."
            ),
            "exact_next_action": (
                "Provide a worktree_path inside canonical branches/ root, e.g., 'branches/issue-...'"
            ),
        }

    dir_exists = os.path.exists(target_worktree)
    if dir_exists:
        # Check porcelain directly
        porc_res = subprocess.run(
            ["git", "-C", target_worktree, "status", "--porcelain"],
            capture_output=True,
            text=True,
            check=False,
        )
        dirty = (
            parse_dirty_tracked_files(porc_res.stdout)
            if porc_res.returncode == 0
            else []
        )
        if dirty or (porc_res.returncode == 0 and porc_res.stdout.strip()):
            journal["failure_reason"] = (
                f"target worktree '{target_worktree}' contains dirty tracked/untracked files"
            )
            run_compensating_recovery(journal, root)
            return {
                "success": False,
                "reason_code": "preexisting_dirty_worktree",
                "message": (
                    f"Preexisting worktree '{target_worktree}' has dirty tracked/untracked files (fail closed)."
                ),
                "exact_next_action": (
                    "Clean or stash the pre-existing worktree files before bootstrapping."
                ),
            }

        # Check registered branch
        wt_state = issue_lock_worktree.read_worktree_git_state(target_worktree)
        wt_branch = (wt_state.get("current_branch") or "").strip()
        if wt_branch and wt_branch != target_branch:
            journal["failure_reason"] = (
                f"existing worktree '{target_worktree}' is on branch '{wt_branch}' != expected '{target_branch}'"
            )
            run_compensating_recovery(journal, root)
            return {
                "success": False,
                "reason_code": "incompatible_existing_directory",
                "message": (
                    f"Existing worktree '{target_worktree}' is registered to branch '{wt_branch}' instead of '{target_branch}'."
                ),
                "exact_next_action": (
                    "Inspect or remove the pre-existing worktree folder before bootstrapping."
                ),
            }
        journal["artifacts_created"]["worktree_dir_created"] = False
    else:
        journal["artifacts_created"]["worktree_dir_created"] = True

    journal["phases"][PHASE_3_PATH_RESERVED] = {
        "status": "completed",
        "worktree_path": target_worktree,
        "preexisting_dir": dir_exists,
    }
    journal["current_phase"] = PHASE_4_WORKTREE_CONFIRMED
    save_phase_journal(journal)

    # Phase 4: WORKTREE_CONFIRMED & Phase 5: REGISTRATION_VERIFIED
    if journal["artifacts_created"]["worktree_dir_created"]:
        wt_add_res = subprocess.run(
            [
                "git",
                "-C",
                root,
                "worktree",
                "add",
                target_worktree,
                target_branch,
            ],
            capture_output=True,
            text=True,
            check=False,
        )
        if wt_add_res.returncode != 0:
            journal["failure_reason"] = (
                f"git worktree add failed: {wt_add_res.stderr.strip()}"
            )
            run_compensating_recovery(journal, root)
            return {
                "success": False,
                "reason_code": "worktree_add_failed",
                "message": f"Failed to execute git worktree add: {wt_add_res.stderr.strip()}",
                "exact_next_action": "Verify git worktree capabilities and retry.",
            }
        journal["artifacts_created"]["worktree_registered"] = True

    # Verify registration in git worktree list
    wt_list_res = subprocess.run(
        ["git", "-C", root, "worktree", "list", "--porcelain"],
        capture_output=True,
        text=True,
        check=False,
    )
    norm_target = os.path.realpath(target_worktree)
    found_registration = False
    if wt_list_res.returncode == 0:
        for block in wt_list_res.stdout.split("\n\n"):
            lines = block.strip().splitlines()
            worktree_line = next(
                (l[9:].strip() for l in lines if l.startswith("worktree ")),
                None,
            )
            if worktree_line and os.path.realpath(worktree_line) == norm_target:
                found_registration = True
                break

    if not found_registration:
        journal["failure_reason"] = (
            f"worktree registration for '{target_worktree}' not found in git worktree list"
        )
        run_compensating_recovery(journal, root)
        return {
            "success": False,
            "reason_code": "worktree_registration_verification_failed",
            "message": f"Worktree '{target_worktree}' registration verification failed.",
            "exact_next_action": "Check git worktree list integrity and retry.",
        }

    journal["phases"][PHASE_4_WORKTREE_CONFIRMED] = {
        "status": "completed",
        "worktree_path": target_worktree,
    }
    journal["phases"][PHASE_5_REGISTRATION_VERIFIED] = {
        "status": "completed",
        "registered": True,
    }
    journal["current_phase"] = PHASE_6_STATE_ESTABLISHED
    save_phase_journal(journal)

    # Phase 6: STATE_ESTABLISHED — Issue Lock Acquisition
    from datetime import datetime, timezone
    try:
        lock_data = {
            "remote": remote,
            "org": org or "Scaled-Tech-Consulting",
            "repo": repo or "Gitea-Tools",
            "issue_number": issue_number,
            "branch": target_branch,
            "branch_name": target_branch,
            "worktree_path": target_worktree,
            "owner_session": owner_session or "prgs-author-95048-63667752",
            "claimant": {
                "username": active_identity or "jcwalker3",
                "profile": active_profile or "prgs-author",
            },
            "assignment_id": assignment_id,
            "lease_id": lease_id,
            "expected_base_sha": live_master_sha,
            "created_at": datetime.now(timezone.utc).isoformat(),
        }
        lock_res = issue_lock_store.bind_session_lock(lock_data, lock_dir=lock_dir)
        journal["artifacts_created"]["lock_created"] = True
    except Exception as exc:
        journal["failure_reason"] = f"issue lock binding failed: {exc}"
        run_compensating_recovery(journal, root)
        return {
            "success": False,
            "reason_code": "issue_lock_acquisition_failed",
            "message": f"Could not bind canonical issue lock for issue #{issue_number}: {exc}",
            "exact_next_action": "Verify lease/assignment state and retry.",
        }

    journal["phases"][PHASE_6_STATE_ESTABLISHED] = {
        "status": "completed",
        "lock": lock_res,
    }
    journal["phases"][PHASE_7_TRANSITION_COMPLETED] = {
        "status": "completed",
    }
    journal["current_phase"] = PHASE_7_TRANSITION_COMPLETED
    journal["completed"] = True
    save_phase_journal(journal)

    return {
        "success": True,
        "replayed": False,
        "message": (
            f"Successfully bootstrapped author issue worktree for issue #{issue_number} "
            f"at branch '{target_branch}' and worktree '{target_worktree}'."
        ),
        "issue_number": issue_number,
        "branch_name": target_branch,
        "worktree_path": target_worktree,
        "base_sha": live_master_sha,
        "lease_id": lease_id,
        "assignment_id": assignment_id,
        "idempotency_key": key,
        "lock_state": lock_res,
        "phase_journal": journal,
        "exact_next_action": (
            f"Call gitea_whoami, then gitea_resolve_task_capability(task='work_issue', worktree_path='{target_worktree}') "
            "and proceed with author implementation in the bootstrapped worktree."
        ),
    }