import json
from ..mcp import mcp
from ..client import _get, _put


@mcp.tool()
def get_issue(issue_id: int) -> str:
    """
    Get a Redmine issue by ID.
    Returns full issue details: title, description, status, priority,
    assignee, progress, dates, custom fields.
    """
    data = _get(f"/issues/{issue_id}.json")
    return json.dumps(data["issue"], ensure_ascii=False, indent=2)


@mcp.tool()
def list_issues(
    project_id: str = "",
    status_id: str = "open",
    assigned_to_id: str = "",
    limit: int = 25,
    offset: int = 0,
) -> str:
    """
    List Redmine issues with optional filters.

    Args:
        project_id:      Filter by project ID or slug (empty = all projects)
        status_id:       "open", "closed", "*" (all), or a numeric status ID
        assigned_to_id:  Numeric user ID, or "me" for the API key owner
        limit:           Max results (1–100, default 25)
        offset:          Pagination offset
    """
    params: dict = {
        "status_id": status_id,
        "limit": min(limit, 100),
        "offset": offset,
    }
    if assigned_to_id:
        params["assigned_to_id"] = assigned_to_id

    path = f"/projects/{project_id}/issues.json" if project_id else "/issues.json"
    data = _get(path, params=params)

    issues = [
        {
            "id": i["id"],
            "subject": i["subject"],
            "status": i["status"]["name"],
            "priority": i["priority"]["name"],
            "assigned_to": i.get("assigned_to", {}).get("name", "—"),
            "done_ratio": i.get("done_ratio", 0),
            "updated_on": i.get("updated_on", ""),
        }
        for i in data.get("issues", [])
    ]
    total = data.get("total_count", len(issues))
    return json.dumps({"total": total, "issues": issues}, ensure_ascii=False, indent=2)


@mcp.tool()
def update_issue(
    issue_id: int,
    subject: str = "",
    description: str = "",
    priority_id: int = 0,
    due_date: str = "",
    comment: str = "",
) -> str:
    """
    Update general fields of a Redmine issue.

    Args:
        issue_id:    Redmine issue ID
        subject:     New title (leave empty to keep current)
        description: New description (leave empty to keep current)
        priority_id: Priority ID (leave 0 to keep current)
        due_date:    Due date in YYYY-MM-DD format (leave empty to keep current)
        comment:     Optional journal note
    """
    payload: dict = {}
    if subject:
        payload["subject"] = subject
    if description:
        payload["description"] = description
    if priority_id:
        payload["priority_id"] = priority_id
    if due_date:
        payload["due_date"] = due_date
    if comment:
        payload["notes"] = comment

    if not payload:
        return "Nothing to update — all fields are empty."

    _put(f"/issues/{issue_id}.json", {"issue": payload})
    return f"Issue #{issue_id} updated: {list(payload.keys())}."


@mcp.tool()
def update_issue_status(issue_id: int, status_id: int, comment: str = "") -> str:
    """
    Change the status of a Redmine issue.

    Args:
        issue_id:  Redmine issue ID
        status_id: Target status ID (use get_issue_statuses to find IDs)
        comment:   Optional comment to add with the status change
    """
    body: dict = {"issue": {"status_id": status_id}}
    if comment:
        body["issue"]["notes"] = comment
    _put(f"/issues/{issue_id}.json", body)
    return f"Issue #{issue_id} status updated to status_id={status_id}."


@mcp.tool()
def update_issue_progress(issue_id: int, done_ratio: int, comment: str = "") -> str:
    """
    Update the % done (progress) of a Redmine issue.

    Args:
        issue_id:   Redmine issue ID
        done_ratio: Progress value 0–100 (percent done)
        comment:    Optional comment to add with the update
    """
    if not 0 <= done_ratio <= 100:
        return "Error: done_ratio must be between 0 and 100."
    body: dict = {"issue": {"done_ratio": done_ratio}}
    if comment:
        body["issue"]["notes"] = comment
    _put(f"/issues/{issue_id}.json", body)
    return f"Issue #{issue_id} progress updated to {done_ratio}%."