#!/usr/bin/env python3
"""
Ticket CLI — ergonomic interface to the project ticketing database.

Usage:
  ticket list [--status S] [--priority P] [--epic N] [--milestone N] [--assigned A] [--team T]
  ticket show <id>
  ticket done <id> [<id> ...]
  ticket status <id> <new_status>
  ticket assign <id> <agent>
  ticket unassign <id>
  ticket team <id> <teams>
  ticket deps <id>
  ticket dep add <blocker_id> <blocked_id>
  ticket dep rm <blocker_id> <blocked_id>
  ticket search <keyword>
  ticket create <type> <title> [--parent N] [--priority P] [--decision D] [--team T] [--description TEXT]
  ticket epics [--status S]
  ticket children <id>
  ticket count [--status S]
  ticket wip
  ticket milestone list [--status S]
  ticket milestone create <name> [--description TEXT] [--phase N]
  ticket milestone link <ticket_id> <milestone_id>
  ticket milestone unlink <ticket_id> <milestone_id>
  ticket milestone complete <milestone_id>
  ticket milestone show <milestone_id>
  ticket milestone dep <blocker_id> <blocked_id>

All output is JSON on stdout.
"""

import json
import sys
from pathlib import Path

sys.path.insert(0, str(Path(__file__).resolve().parent))

from common import get_connection, load_config  # noqa: E402

WIP_LIMIT = 3


def query(conn, sql, params=()):
    cursor = conn.execute(sql, params)
    columns = [desc[0] for desc in cursor.description] if cursor.description else []
    return [dict(zip(columns, row)) for row in cursor.fetchall()]


def execute(conn, sql, params=()):
    cursor = conn.execute(sql, params)
    conn.commit()
    return cursor.rowcount


def out(data):
    print(json.dumps(data, indent=2))


def parse_flags(args, known_flags):
    """Parse --flag value pairs from args, return (flags_dict, positional_args)."""
    flags = {}
    positional = []
    i = 0
    while i < len(args):
        if args[i].startswith("--") and args[i][2:] in known_flags:
            key = args[i][2:]
            if i + 1 < len(args):
                flags[key] = args[i + 1]
                i += 2
            else:
                positional.append(args[i])
                i += 1
        else:
            positional.append(args[i])
            i += 1
    return flags, positional


# ---------------------------------------------------------------------------
# Commands
# ---------------------------------------------------------------------------

def cmd_list(conn, args):
    flags, _ = parse_flags(args, ["status", "priority", "epic", "milestone", "assigned", "team"])
    conditions = []
    params = []
    join = ""
    if "status" in flags:
        conditions.append("t.status = ?")
        params.append(flags["status"])
    if "priority" in flags:
        conditions.append("t.priority = ?")
        params.append(flags["priority"])
    if "epic" in flags:
        conditions.append("t.parent_id = ?")
        params.append(int(flags["epic"]))
    if "milestone" in flags:
        join = "JOIN ticket_milestones tm ON tm.ticket_id = t.id"
        conditions.append("tm.milestone_id = ?")
        params.append(int(flags["milestone"]))
    if "assigned" in flags:
        conditions.append("t.assigned_to = ?")
        params.append(flags["assigned"])
    if "team" in flags:
        conditions.append("(',' || t.team || ',' LIKE '%,' || ? || ',%')")
        params.append(flags["team"])
    where = " AND ".join(conditions) if conditions else "1=1"
    sql = f"""SELECT DISTINCT t.id, t.type, t.title, t.status, t.priority, t.assigned_to,
                     t.team, t.parent_id
              FROM tickets t {join} WHERE {where}
              ORDER BY
                CASE t.priority WHEN 'critical' THEN 0 WHEN 'high' THEN 1
                WHEN 'medium' THEN 2 ELSE 3 END, t.id"""
    rows = query(conn, sql, tuple(params))
    out({"ok": True, "count": len(rows), "rows": rows})


def cmd_show(conn, ids, brief=False):
    tickets = []
    for ticket_id in ids:
        rows = query(conn, """SELECT t.*, p.title as parent_title
                              FROM tickets t LEFT JOIN tickets p ON t.parent_id = p.id
                              WHERE t.id = ?""", (ticket_id,))
        if not rows:
            tickets.append({"id": ticket_id, "error": f"Ticket #{ticket_id} not found"})
            continue
        ticket = rows[0]
        children = query(conn, "SELECT id, title, status, priority FROM tickets WHERE parent_id = ? ORDER BY id", (ticket_id,))
        blockers = query(conn, """SELECT t.id, t.title, t.status FROM ticket_deps d
                                  JOIN tickets t ON d.blocker_id = t.id
                                  WHERE d.blocked_id = ?""", (ticket_id,))
        blocks = query(conn, """SELECT t.id, t.title, t.status FROM ticket_deps d
                                JOIN tickets t ON d.blocked_id = t.id
                                WHERE d.blocker_id = ?""", (ticket_id,))
        milestones = query(conn, """SELECT m.id, m.name, m.status FROM ticket_milestones tm
                                    JOIN milestones m ON tm.milestone_id = m.id
                                    WHERE tm.ticket_id = ?""", (ticket_id,))
        ticket["children"] = children
        ticket["blocked_by"] = blockers
        ticket["blocks"] = blocks
        ticket["milestones"] = milestones
        tickets.append(ticket)
    if brief:
        _print_brief(tickets)
    elif len(tickets) == 1:
        out({"ok": True, "ticket": tickets[0]})
    else:
        out({"ok": True, "count": len(tickets), "tickets": tickets})


def _print_brief(tickets):
    for i, t in enumerate(tickets):
        if "error" in t:
            print(f"#{t['id']}: NOT FOUND")
            continue
        print(f"#{t['id']}: {t['title']}")
        parts = [f"{t['type']}", f"P:{t['priority']}", f"S:{t['status']}"]
        if t.get("assigned_to"):
            parts.append(f"@{t['assigned_to']}")
        if t.get("team"):
            parts.append(f"Team:{t['team']}")
        if t.get("parent_id"):
            parts.append(f"Epic:#{t['parent_id']} ({t.get('parent_title', '?')})")
        if t.get("milestones"):
            ms = ", ".join(f"M{m['id']}" for m in t["milestones"])
            parts.append(f"Milestones:{ms}")
        if t.get("decision_ref"):
            parts.append(f"Ref:{t['decision_ref']}")
        print(f"  {' | '.join(parts)}")
        desc = t.get("description") or ""
        if desc:
            if len(desc) > 200:
                desc = desc[:197] + "..."
            print(f"  {desc}")
        if t.get("blocked_by"):
            blockers = ", ".join(f"#{b['id']} ({b['status']})" for b in t["blocked_by"])
            print(f"  Blocked by: {blockers}")
        if t.get("blocks"):
            blocks = ", ".join(f"#{b['id']}" for b in t["blocks"])
            print(f"  Blocks: {blocks}")
        if i < len(tickets) - 1:
            print()


def cmd_done(conn, ids):
    updated = 0
    for tid in ids:
        updated += execute(conn, "UPDATE tickets SET status='done', updated_at=datetime('now') WHERE id=?", (int(tid),))
    out({"ok": True, "updated": updated, "ids": [int(i) for i in ids]})


def cmd_status(conn, ticket_id, new_status):
    valid = ('backlog', 'ready', 'in_progress', 'review', 'done', 'cancelled')
    if new_status not in valid:
        out({"ok": False, "error": f"Invalid status '{new_status}'. Valid: {', '.join(valid)}"})
        return
    if new_status == 'in_progress':
        wip = query(conn, "SELECT COUNT(*) as count FROM tickets WHERE status = 'in_progress'")
        count = wip[0]["count"]
        if count >= WIP_LIMIT:
            print(f"WARNING: WIP limit ({WIP_LIMIT}) reached — {count} tickets already in_progress", file=sys.stderr)
    updated = execute(conn, "UPDATE tickets SET status=?, updated_at=datetime('now') WHERE id=?", (new_status, int(ticket_id)))
    out({"ok": True, "updated": updated, "id": int(ticket_id), "status": new_status})


def cmd_assign(conn, ticket_id, agent):
    updated = execute(conn, "UPDATE tickets SET assigned_to=?, updated_at=datetime('now') WHERE id=?", (agent, int(ticket_id)))
    out({"ok": True, "updated": updated, "id": int(ticket_id), "assigned_to": agent})


def cmd_unassign(conn, ticket_id):
    updated = execute(conn, "UPDATE tickets SET assigned_to=NULL, updated_at=datetime('now') WHERE id=?", (int(ticket_id),))
    out({"ok": True, "updated": updated, "id": int(ticket_id), "assigned_to": None})


def cmd_deps(conn, ticket_id):
    blockers = query(conn, """SELECT t.id, t.title, t.status, t.priority FROM ticket_deps d
                              JOIN tickets t ON d.blocker_id = t.id
                              WHERE d.blocked_id = ? ORDER BY t.id""", (int(ticket_id),))
    blocks = query(conn, """SELECT t.id, t.title, t.status, t.priority FROM ticket_deps d
                            JOIN tickets t ON d.blocked_id = t.id
                            WHERE d.blocker_id = ? ORDER BY t.id""", (int(ticket_id),))
    out({"ok": True, "id": int(ticket_id), "blocked_by": blockers, "blocks": blocks})


def cmd_dep(conn, args):
    if len(args) < 3:
        out({"ok": False, "error": "Usage: ticket dep add|rm <blocker_id> <blocked_id>"})
        return
    action, blocker_id, blocked_id = args[0], int(args[1]), int(args[2])
    if action == "add":
        try:
            execute(conn, "INSERT INTO ticket_deps (blocker_id, blocked_id) VALUES (?, ?)", (blocker_id, blocked_id))
            out({"ok": True, "action": "added", "blocker_id": blocker_id, "blocked_id": blocked_id})
        except Exception as e:
            out({"ok": False, "error": str(e)})
    elif action == "rm":
        updated = execute(conn, "DELETE FROM ticket_deps WHERE blocker_id = ? AND blocked_id = ?", (blocker_id, blocked_id))
        out({"ok": True, "action": "removed", "updated": updated, "blocker_id": blocker_id, "blocked_id": blocked_id})
    else:
        out({"ok": False, "error": f"Unknown dep action: {action}. Use 'add' or 'rm'."})


def cmd_search(conn, keyword):
    rows = query(conn, """SELECT id, type, title, status, priority, assigned_to, team
                          FROM tickets WHERE title LIKE ? OR description LIKE ?
                          ORDER BY id""", (f"%{keyword}%", f"%{keyword}%"))
    out({"ok": True, "count": len(rows), "rows": rows})


def cmd_create(conn, args):
    flags, positional = parse_flags(args, ["parent", "priority", "decision", "team", "description"])
    if len(positional) < 2:
        out({"ok": False, "error": "Usage: ticket create <type> <title> [--parent N] [--priority P] [--decision D] [--team T] [--description TEXT]"})
        return
    ticket_type = positional[0]
    title = " ".join(positional[1:])
    parent_id = int(flags["parent"]) if "parent" in flags else None
    priority = flags.get("priority", "medium")
    decision_ref = flags.get("decision")
    team = flags.get("team")
    description = flags.get("description")
    conn.execute(
        "INSERT INTO tickets (type, title, description, parent_id, priority, decision_ref, team) VALUES (?, ?, ?, ?, ?, ?, ?)",
        (ticket_type, title, description, parent_id, priority, decision_ref, team))
    conn.commit()
    last_id = query(conn, "SELECT last_insert_rowid() as id")[0]["id"]
    out({"ok": True, "id": last_id, "title": title})


def cmd_epics(conn, args):
    flags, _ = parse_flags(args, ["status"])
    conditions = ["t.type = 'epic'"]
    params = []
    if "status" in flags:
        conditions.append("t.status = ?")
        params.append(flags["status"])
    where = " AND ".join(conditions)
    rows = query(conn, f"""SELECT t.id, t.title, t.status, t.priority, t.assigned_to, t.team,
                           COUNT(c.id) as child_count,
                           SUM(CASE WHEN c.status='done' THEN 1 ELSE 0 END) as done_count
                           FROM tickets t LEFT JOIN tickets c ON c.parent_id = t.id
                           WHERE {where} GROUP BY t.id
                           ORDER BY CASE t.priority WHEN 'critical' THEN 0 WHEN 'high' THEN 1
                           WHEN 'medium' THEN 2 ELSE 3 END, t.id""", tuple(params))
    out({"ok": True, "count": len(rows), "rows": rows})


def cmd_children(conn, ticket_id):
    rows = query(conn, """SELECT id, type, title, status, priority, assigned_to, team
                          FROM tickets WHERE parent_id = ? ORDER BY id""", (int(ticket_id),))
    out({"ok": True, "count": len(rows), "parent_id": int(ticket_id), "rows": rows})


def cmd_team(conn, ticket_id, teams):
    updated = execute(conn, "UPDATE tickets SET team=?, updated_at=datetime('now') WHERE id=?", (teams, int(ticket_id)))
    out({"ok": True, "updated": updated, "id": int(ticket_id), "team": teams})


def cmd_count(conn, args):
    flags, _ = parse_flags(args, ["status"])
    if "status" in flags:
        rows = query(conn, "SELECT COUNT(*) as count FROM tickets WHERE status = ?", (flags["status"],))
    else:
        rows = query(conn, "SELECT status, COUNT(*) as count FROM tickets GROUP BY status ORDER BY count DESC")
    out({"ok": True, "rows": rows})


def cmd_wip(conn):
    rows = query(conn, """SELECT id, title, assigned_to, team FROM tickets
                          WHERE status = 'in_progress' ORDER BY id""")
    count = len(rows)
    out({"ok": True, "in_progress": count, "limit": WIP_LIMIT,
         "over_limit": count > WIP_LIMIT, "tickets": rows})


# ---------------------------------------------------------------------------
# Milestone commands
# ---------------------------------------------------------------------------

def cmd_milestone(conn, args):
    if not args:
        out({"ok": False, "error": "Usage: ticket milestone list|create|link|unlink|complete|show|dep ..."})
        return

    sub = args[0]
    rest = args[1:]

    if sub == "list":
        cmd_milestone_list(conn, rest)
    elif sub == "create":
        cmd_milestone_create(conn, rest)
    elif sub == "link":
        cmd_milestone_link(conn, rest)
    elif sub == "unlink":
        cmd_milestone_unlink(conn, rest)
    elif sub == "complete":
        cmd_milestone_complete(conn, rest)
    elif sub == "show":
        cmd_milestone_show(conn, rest)
    elif sub == "dep":
        cmd_milestone_dep(conn, rest)
    else:
        out({"ok": False, "error": f"Unknown milestone subcommand: {sub}"})


def cmd_milestone_list(conn, args):
    flags, _ = parse_flags(args, ["status"])
    conditions = []
    params = []
    if "status" in flags:
        conditions.append("m.status = ?")
        params.append(flags["status"])
    where = " AND ".join(conditions) if conditions else "1=1"
    rows = query(conn, f"""SELECT m.*,
                           COUNT(DISTINCT tm.ticket_id) as ticket_count,
                           SUM(CASE WHEN t.status = 'done' THEN 1 ELSE 0 END) as done_count
                           FROM milestones m
                           LEFT JOIN ticket_milestones tm ON tm.milestone_id = m.id
                           LEFT JOIN tickets t ON t.id = tm.ticket_id
                           WHERE {where}
                           GROUP BY m.id ORDER BY m.id""", tuple(params))
    out({"ok": True, "count": len(rows), "milestones": rows})


def cmd_milestone_create(conn, args):
    flags, positional = parse_flags(args, ["description", "phase"])
    if not positional:
        out({"ok": False, "error": "Usage: ticket milestone create <name> [--description TEXT] [--phase N]"})
        return
    name = " ".join(positional)
    description = flags.get("description")
    phase = int(flags["phase"]) if "phase" in flags else None
    conn.execute(
        "INSERT INTO milestones (name, description, cascade_phase) VALUES (?, ?, ?)",
        (name, description, phase))
    conn.commit()
    last_id = query(conn, "SELECT last_insert_rowid() as id")[0]["id"]
    out({"ok": True, "id": last_id, "name": name})


def cmd_milestone_link(conn, args):
    if len(args) < 2:
        out({"ok": False, "error": "Usage: ticket milestone link <ticket_id> <milestone_id>"})
        return
    ticket_id, milestone_id = int(args[0]), int(args[1])
    try:
        execute(conn, "INSERT INTO ticket_milestones (ticket_id, milestone_id) VALUES (?, ?)", (ticket_id, milestone_id))
        out({"ok": True, "action": "linked", "ticket_id": ticket_id, "milestone_id": milestone_id})
    except Exception as e:
        out({"ok": False, "error": str(e)})


def cmd_milestone_unlink(conn, args):
    if len(args) < 2:
        out({"ok": False, "error": "Usage: ticket milestone unlink <ticket_id> <milestone_id>"})
        return
    ticket_id, milestone_id = int(args[0]), int(args[1])
    updated = execute(conn, "DELETE FROM ticket_milestones WHERE ticket_id = ? AND milestone_id = ?", (ticket_id, milestone_id))
    out({"ok": True, "action": "unlinked", "updated": updated, "ticket_id": ticket_id, "milestone_id": milestone_id})


def cmd_milestone_complete(conn, args):
    if not args:
        out({"ok": False, "error": "Usage: ticket milestone complete <milestone_id>"})
        return
    milestone_id = int(args[0])
    updated = execute(conn, "UPDATE milestones SET status='completed', completed_at=datetime('now') WHERE id=?", (milestone_id,))
    out({"ok": True, "updated": updated, "id": milestone_id, "status": "completed"})


def cmd_milestone_show(conn, args):
    if not args:
        out({"ok": False, "error": "Usage: ticket milestone show <milestone_id>"})
        return
    milestone_id = int(args[0])
    ms = query(conn, "SELECT * FROM milestones WHERE id = ?", (milestone_id,))
    if not ms:
        out({"ok": False, "error": f"Milestone #{milestone_id} not found"})
        return
    milestone = ms[0]
    tickets = query(conn, """SELECT t.id, t.type, t.title, t.status, t.priority, t.assigned_to
                             FROM ticket_milestones tm JOIN tickets t ON t.id = tm.ticket_id
                             WHERE tm.milestone_id = ?
                             ORDER BY CASE t.priority WHEN 'critical' THEN 0 WHEN 'high' THEN 1
                             WHEN 'medium' THEN 2 ELSE 3 END, t.id""", (milestone_id,))
    blockers = query(conn, """SELECT m.id, m.name, m.status FROM milestone_deps d
                              JOIN milestones m ON d.blocker_id = m.id
                              WHERE d.blocked_id = ?""", (milestone_id,))
    blocks = query(conn, """SELECT m.id, m.name, m.status FROM milestone_deps d
                            JOIN milestones m ON d.blocked_id = m.id
                            WHERE d.blocker_id = ?""", (milestone_id,))
    milestone["tickets"] = tickets
    milestone["blocked_by"] = blockers
    milestone["blocks"] = blocks
    out({"ok": True, "milestone": milestone})


def cmd_milestone_dep(conn, args):
    if len(args) < 2:
        out({"ok": False, "error": "Usage: ticket milestone dep <blocker_id> <blocked_id>"})
        return
    blocker_id, blocked_id = int(args[0]), int(args[1])
    try:
        execute(conn, "INSERT INTO milestone_deps (blocker_id, blocked_id) VALUES (?, ?)", (blocker_id, blocked_id))
        out({"ok": True, "action": "added", "blocker_id": blocker_id, "blocked_id": blocked_id})
    except Exception as e:
        out({"ok": False, "error": str(e)})


# ---------------------------------------------------------------------------
# CLI
# ---------------------------------------------------------------------------

HELP = """ticket — project ticket CLI

Usage:
  ticket list [--status S] [--priority P] [--epic N] [--milestone N] [--assigned A] [--team T]
  ticket show [--brief] <id> [<id>...] Full ticket detail (--brief for summary)
  ticket done <id> [<id> ...]         Mark tickets as done
  ticket status <id> <new_status>     Change ticket status
  ticket assign <id> <agent>          Assign ticket to agent
  ticket unassign <id>                Remove assignment
  ticket team <id> <teams>            Set team(s) (comma-separated)
  ticket deps <id>                    Show ticket dependencies
  ticket dep add <blocker> <blocked>  Add ticket dependency
  ticket dep rm <blocker> <blocked>   Remove ticket dependency
  ticket search <keyword>             Search tickets by title/description
  ticket create <type> <title> [--parent N] [--priority P] [--decision D] [--team T] [--description TEXT]
  ticket epics [--status S]           List epics with child counts
  ticket children <id>                List children of a ticket
  ticket count [--status S]           Count tickets by status
  ticket wip                          Show in-progress count vs WIP limit
  ticket milestone list [--status S]            List milestones
  ticket milestone create <name> [--description TEXT] [--phase N]  Create milestone
  ticket milestone link <ticket> <milestone>    Link ticket to milestone
  ticket milestone unlink <ticket> <milestone>  Unlink ticket from milestone
  ticket milestone complete <milestone>         Mark milestone completed
  ticket milestone show <milestone>             Show milestone with tickets
  ticket milestone dep <blocker> <blocked>      Add milestone dependency"""


def main():
    if len(sys.argv) < 2 or sys.argv[1] in ("--help", "-h", "help"):
        print(HELP)
        sys.exit(0)

    try:
        cfg = load_config()
    except (FileNotFoundError, json.JSONDecodeError) as exc:
        out({"ok": False, "error": f"Config error: {exc}"})
        sys.exit(1)

    conn = get_connection(cfg)
    cmd = sys.argv[1]
    args = sys.argv[2:]

    try:
        if cmd == "list":
            cmd_list(conn, args)
        elif cmd == "show":
            brief = "--brief" in args
            id_args = [a for a in args if a != "--brief"]
            if not id_args:
                out({"ok": False, "error": "Usage: ticket show [--brief] <id> [<id> ...]"})
            else:
                cmd_show(conn, [int(a) for a in id_args], brief=brief)
        elif cmd == "done":
            if not args:
                out({"ok": False, "error": "Usage: ticket done <id> [<id> ...]"})
            else:
                cmd_done(conn, args)
        elif cmd == "status":
            if len(args) < 2:
                out({"ok": False, "error": "Usage: ticket status <id> <new_status>"})
            else:
                cmd_status(conn, args[0], args[1])
        elif cmd == "assign":
            if len(args) < 2:
                out({"ok": False, "error": "Usage: ticket assign <id> <agent>"})
            else:
                cmd_assign(conn, args[0], args[1])
        elif cmd == "unassign":
            if not args:
                out({"ok": False, "error": "Usage: ticket unassign <id>"})
            else:
                cmd_unassign(conn, args[0])
        elif cmd == "team":
            if len(args) < 2:
                out({"ok": False, "error": "Usage: ticket team <id> <teams>"})
            else:
                cmd_team(conn, args[0], args[1])
        elif cmd == "deps":
            if not args:
                out({"ok": False, "error": "Usage: ticket deps <id>"})
            else:
                cmd_deps(conn, args[0])
        elif cmd == "dep":
            cmd_dep(conn, args)
        elif cmd == "search":
            if not args:
                out({"ok": False, "error": "Usage: ticket search <keyword>"})
            else:
                cmd_search(conn, " ".join(args))
        elif cmd == "create":
            cmd_create(conn, args)
        elif cmd == "epics":
            cmd_epics(conn, args)
        elif cmd == "children":
            if not args:
                out({"ok": False, "error": "Usage: ticket children <id>"})
            else:
                cmd_children(conn, args[0])
        elif cmd == "count":
            cmd_count(conn, args)
        elif cmd == "wip":
            cmd_wip(conn)
        elif cmd == "milestone":
            cmd_milestone(conn, args)
        else:
            out({"ok": False, "error": f"Unknown command: {cmd}. Use --help for usage."})
    finally:
        conn.close()


if __name__ == "__main__":
    main()