# -*- coding: utf-8 -*-
"""
fsm.py — Конечный автомат (Finite State Machine) для миграции.
Каждый mode (source/target) имеет свой pipeline steps.
"""

from core import state
from core.color import header, subheader, success, error as cerror, warn, info, step


class FSM:
    SOURCE_STEPS = [
        "INIT",
        "SOURCE_DISCOVER",
        "SOURCE_MANIFEST_REVIEW",
        "SOURCE_PACK",
        "SOURCE_STOP_SERVICE",
        "TRANSFER",
        "DONE",
    ]

    TARGET_STEPS = [
        "INIT",
        "TARGET_PREFLIGHT",
        "TARGET_INSTALL",
        "TARGET_BACKUP",
        "TARGET_RESTORE",
        "TARGET_VERIFY",
        "DONE",
    ]

    def __init__(self, mode="source"):
        self.mode = mode
        self.steps = self.SOURCE_STEPS if mode == "source" else self.TARGET_STEPS

    def _index(self, stage):
        try:
            return self.steps.index(stage)
        except ValueError:
            return -1

    def resume_from(self, stage):
        idx = self._index(stage)
        if idx < 0:
            warn(f"Неизвестный stage '{stage}', начинаем с начала")
            idx = 0
        for s in self.steps[idx:]:
            if state.is_completed(s):
                info(f"Шаг {s} уже выполнен, пропускаем")
                continue
            self._run_step(s)

    def _run_step(self, step_name):
        header(f"ШАГ: {step_name}")
        try:
            if self.mode == "source":
                self._source_step(step_name)
            else:
                self._target_step(step_name)
            state.mark_completed(step_name)
            state.set_stage(step_name)
        except Exception as e:
            msg = str(e)
            cerror(f"Ошибка на шаге {step_name}: {msg}")
            state.set_error(step_name, "", msg, suggestion="Исправьте проблему и запустите: docker-migrate --resume")
            raise

    def _source_step(self, name):
        if name == "INIT":
            info("Инициализация source-режима")
        elif name == "SOURCE_DISCOVER":
            from source.source import do_discovery
            do_discovery()
        elif name == "SOURCE_MANIFEST_REVIEW":
            from source.source import do_manifest_review
            do_manifest_review()
        elif name == "SOURCE_PACK":
            from source.source import do_pack
            do_pack()
        elif name == "SOURCE_STOP_SERVICE":
            from source.source import do_stop_service
            do_stop_service()
        elif name == "TRANSFER":
            from transfer.transfer import do_transfer
            do_transfer()
        elif name == "DONE":
            success("Source-режим завершён")

    def _target_step(self, name):
        if name == "INIT":
            info("Инициализация target-режима")
        elif name == "TARGET_PREFLIGHT":
            from target.target import do_preflight
            do_preflight()
        elif name == "TARGET_INSTALL":
            from target.target import do_install
            do_install()
        elif name == "TARGET_BACKUP":
            from target.target import do_backup_existing
            do_backup_existing()
        elif name == "TARGET_RESTORE":
            from target.target import do_restore
            do_restore()
        elif name == "TARGET_VERIFY":
            from target.target import do_verify
            do_verify()
        elif name == "DONE":
            success("Target-режим завершён")