from __future__ import annotations

import os
from dataclasses import dataclass
from pathlib import Path

_DEFAULT_SETUP_COMMANDS = (
    "composer install --no-interaction --prefer-dist;;"
    "npm ci;;"
    "npm run build;;"
    "php artisan migrate:fresh --force"
)


def _bool(name: str, default: bool = False) -> bool:
    return os.getenv(name, str(default)).lower() in {"1", "true", "yes", "on"}


def _commands(value: str) -> tuple[str, ...]:
    return tuple(command.strip() for command in value.split(";;") if command.strip())


@dataclass(frozen=True)
class Settings:
    database_host: str
    database_port: int
    database_name: str
    database_user: str
    database_password: str
    source_repository: str
    source_branch: str
    workspace_root: Path
    mode: str
    allow_direct_main: bool
    gitea_url: str
    gitea_owner: str
    gitea_repository: str
    gitea_token: str
    gitea_username: str
    agent_command: str
    agent_model: str
    agent_timeout_seconds: int
    agent_idle_timeout_seconds: int
    setup_commands: tuple[str, ...]
    test_commands: tuple[str, ...]
    test_database_host: str
    test_database_port: int
    test_database_name: str
    test_database_user: str
    test_database_password: str
    test_customer_database: str
    test_config_database: str
    poll_seconds: int
    max_changed_files: int
    max_changed_lines: int
    max_agent_attempts: int
    stale_claim_minutes: int
    dry_run: bool

    @classmethod
    def from_env(cls) -> Settings:
        mode = os.getenv("AUTOMATION_MODE", "dry-run").lower()
        if mode not in {"dry-run", "pr", "direct-main"}:
            raise ValueError("AUTOMATION_MODE must be dry-run, pr, or direct-main")

        settings = cls(
            database_host=os.getenv("FAILURE_DB_HOST", "host.docker.internal"),
            database_port=int(os.getenv("FAILURE_DB_PORT", "33060")),
            database_name=os.getenv("FAILURE_DB_NAME", "laravel_ai_chat"),
            database_user=os.getenv("FAILURE_DB_USER", "laravel"),
            database_password=os.getenv("FAILURE_DB_PASSWORD", ""),
            source_repository=os.getenv(
                "SOURCE_REPOSITORY", "https://gitea.tisinfra.de/christian.meyer/lai.git"
            ),
            source_branch=os.getenv("SOURCE_BRANCH", "main"),
            workspace_root=Path(os.getenv("WORKSPACE_ROOT", "/workspaces")),
            mode=mode,
            allow_direct_main=_bool("ALLOW_DIRECT_MAIN"),
            gitea_url=os.getenv("GITEA_URL", "https://gitea.tisinfra.de"),
            gitea_owner=os.getenv("GITEA_OWNER", "christian.meyer"),
            gitea_repository=os.getenv("GITEA_REPOSITORY", "lai"),
            gitea_token=os.getenv("GITEA_TOKEN", ""),
            gitea_username=os.getenv("GITEA_USERNAME", "automation-bot"),
            agent_command=os.getenv("AGENT_COMMAND", "aider"),
            agent_model=os.getenv("AGENT_MODEL", "mistral/devstral-latest"),
            agent_timeout_seconds=int(os.getenv("AGENT_TIMEOUT_SECONDS", "900")),
            agent_idle_timeout_seconds=int(os.getenv("AGENT_IDLE_TIMEOUT_SECONDS", "300")),
            setup_commands=_commands(
                os.getenv("SETUP_COMMANDS", _DEFAULT_SETUP_COMMANDS)
            ),
            test_commands=_commands(
                os.getenv("TEST_COMMANDS", "php artisan test")
            ),
            test_database_host=os.getenv("TEST_DB_HOST", "host.docker.internal"),
            test_database_port=int(os.getenv("TEST_DB_PORT", "33060")),
            test_database_name=os.getenv("TEST_DB_NAME", "laravel_ai_chat_agent_test"),
            test_database_user=os.getenv("TEST_DB_USER", "lai_test_runner"),
            test_database_password=os.getenv("TEST_DB_PASSWORD", ""),
            test_customer_database=os.getenv("TEST_CUSTOMER_DB", "customer_agent_test"),
            test_config_database=os.getenv("TEST_CONFIG_DB", "cockpit_agent_test"),
            poll_seconds=int(os.getenv("POLL_SECONDS", "60")),
            max_changed_files=int(os.getenv("MAX_CHANGED_FILES", "12")),
            max_changed_lines=int(os.getenv("MAX_CHANGED_LINES", "800")),
            max_agent_attempts=int(os.getenv("MAX_AGENT_ATTEMPTS", "2")),
            stale_claim_minutes=int(os.getenv("STALE_CLAIM_MINUTES", "90")),
            dry_run=mode == "dry-run",
        )
        settings.validate()
        return settings

    def validate(self) -> None:
        if self.mode == "direct-main" and not self.allow_direct_main:
            raise ValueError("direct-main requires ALLOW_DIRECT_MAIN=true")
        if self.mode in {"pr", "direct-main"} and not self.gitea_token:
            raise ValueError(f"{self.mode} requires GITEA_TOKEN")
        if not self.database_password:
            raise ValueError("FAILURE_DB_PASSWORD is required")
        if not self.test_database_password:
            raise ValueError("TEST_DB_PASSWORD is required")
        if not self.test_commands:
            raise ValueError("TEST_COMMANDS must contain at least one command")
        test_databases = {
            "TEST_DB_NAME": self.test_database_name,
            "TEST_CUSTOMER_DB": self.test_customer_database,
            "TEST_CONFIG_DB": self.test_config_database,
        }
        for setting_name, database_name in test_databases.items():
            if "test" not in database_name.lower():
                raise ValueError(f"{setting_name} must name an isolated test database")
            if database_name == self.database_name:
                raise ValueError(f"{setting_name} must differ from FAILURE_DB_NAME")
        if len(set(test_databases.values())) != len(test_databases):
            raise ValueError("TEST_DB_NAME, TEST_CUSTOMER_DB, and TEST_CONFIG_DB must be distinct")
        if not 60 <= self.agent_timeout_seconds <= 3600:
            raise ValueError("AGENT_TIMEOUT_SECONDS must be between 60 and 3600")
        if not 60 <= self.agent_idle_timeout_seconds <= self.agent_timeout_seconds:
            raise ValueError(
                "AGENT_IDLE_TIMEOUT_SECONDS must be between 60 and AGENT_TIMEOUT_SECONDS"
            )
        if not 1 <= self.max_agent_attempts <= 7:
            raise ValueError("MAX_AGENT_ATTEMPTS must be between 1 and 7")