from typing import Any

from ..core.database import (
    ChangeSet,
    DatabaseCommand,
    execute_command,
    execute_locked_command,
    g_add_prefix,
    g_delete_prefix,
    g_update_prefix,
    read_all,
    sql_literal,
    try_read,
)
from ..gis.coordinates import (
    get_node_coord,
    sql_delete_coord,
    sql_insert_coord,
    sql_update_coord,
)
from .elements import get_all_node_links, get_node_links


def get_reservoir_schema(name: str) -> dict[str, dict[str, Any]]:
    return { 'id'      : {'type': 'str'      , 'optional': False , 'readonly': True },
             'x'       : {'type': 'float'    , 'optional': False , 'readonly': False},
             'y'       : {'type': 'float'    , 'optional': False , 'readonly': False},
             'head'    : {'type': 'float'    , 'optional': False , 'readonly': False},
             'pattern' : {'type': 'str'      , 'optional': True  , 'readonly': False},
             'links'   : {'type': 'str_list' , 'optional': False , 'readonly': True } }


def get_reservoir(name: str, id: str) -> dict[str, Any]:
    r = try_read(name, "select node_id as id, head, pattern_id as pattern from network.reservoirs where node_id = %s", (id,))
    if r == None:
        return {}
    xy = get_node_coord(name, id)
    d = {}
    d['id'] = str(r['id'])
    d['x'] = float(xy['x'])
    d['y'] = float(xy['y'])
    d['head'] = float(r['head'])
    d['pattern'] = str(r['pattern']) if r['pattern'] != None else None
    d['links'] = get_node_links(name, id)
    return d

# DingZQ, 2025-03-29
def get_all_reservoirs(name: str) -> list[dict[str, Any]]:
    rows = read_all(
        name,
        "SELECT id, head, pattern_id AS pattern, x, y "
        "FROM gis.reservoirs ORDER BY id",
    )
    if rows == None:
        return []

    links_by_node = get_all_node_links(name)
    result = []
    for row in rows:
        d = {}
        id = str(row['id']) 
        d['id'] = id
        d['x'] = float(row['x'] or 0.0)
        d['y'] = float(row['y'] or 0.0)
        d['head'] = float(row['head']) if row['head'] != None else None
        d['pattern'] = str(row['pattern']) if row['pattern'] != None else None
        d['links'] = links_by_node.get(id, [])
        result.append(d)

    return result

class Reservoir(object):
    def __init__(self, input: dict[str, Any]) -> None:
        self.type = 'reservoir'
        self.id = str(input['id'])
        self.x = float(input['x'])
        self.y = float(input['y'])
        self.head = float(input['head'])
        self.pattern = str(input['pattern']) if 'pattern' in input and input['pattern'] != None else None

        self.f_type = sql_literal(self.type)
        self.f_id = sql_literal(self.id)
        self.f_head = sql_literal(self.head)
        self.f_pattern = sql_literal(self.pattern)

    def as_dict(self) -> dict[str, Any]:
        return { 'type': self.type, 'id': self.id, 'x': self.x, 'y': self.y, 'head': self.head, 'pattern': self.pattern }

def _set_reservoir(
    name: str,
    cs: ChangeSet,
    current: dict[str, Any] | None = None,
) -> DatabaseCommand:
    raw_new = current if current is not None else get_reservoir(name, cs.operations[0]['id'])

    new_dict = cs.operations[0]
    schema = get_reservoir_schema(name)
    for key, value in schema.items():
        if key in new_dict and not value['readonly']:
            raw_new[key] = new_dict[key]
    new = Reservoir(raw_new)

    statement = f"update network.reservoirs set head = {new.f_head}, pattern_id = {new.f_pattern} where node_id = {new.f_id};"
    statement += f"\n{sql_update_coord(new.id, new.x, new.y)}"

    change = g_update_prefix | new.as_dict()

    return DatabaseCommand(statement, [change])


def set_reservoir(name: str, cs: ChangeSet) -> ChangeSet:
    operation = cs.operations[0]
    if 'id' not in operation:
        return ChangeSet()

    def build_command() -> DatabaseCommand | None:
        current = get_reservoir(name, operation['id'])
        return None if current == {} else _set_reservoir(name, cs, current)

    return execute_locked_command(name, build_command)


def _add_reservoir(name: str, cs: ChangeSet) -> DatabaseCommand:
    new = Reservoir(cs.operations[0])

    statement = f"insert into network.nodes (id, node_type) values ({new.f_id}, {new.f_type});"
    statement += f"\ninsert into network.reservoirs (node_id, head, pattern_id) values ({new.f_id}, {new.f_head}, {new.f_pattern});"
    statement += f"\n{sql_insert_coord(new.id, new.x, new.y)}"

    change = g_add_prefix | new.as_dict()

    return DatabaseCommand(statement, [change])


def add_reservoir(name: str, cs: ChangeSet) -> ChangeSet:
    if 'id' not in cs.operations[0]:
        return ChangeSet()
    if get_reservoir(name, cs.operations[0]['id']) != {}:
        return ChangeSet()
    return execute_command(name, _add_reservoir(name, cs))


def _delete_reservoir(name: str, cs: ChangeSet) -> DatabaseCommand:
    element_id = str(cs.operations[0]['id'])
    f_id = sql_literal(element_id)

    statement = sql_delete_coord(element_id)
    statement += f"\ndelete from network.nodes where id = {f_id};"

    change = g_delete_prefix | {'type': 'reservoir', 'id': element_id}

    return DatabaseCommand(statement, [change])


def delete_reservoir(name: str, cs: ChangeSet) -> ChangeSet:
    if 'id' not in cs.operations[0]:
        return ChangeSet()
    if get_reservoir(name, cs.operations[0]['id']) == {}:
        return ChangeSet()
    return execute_command(name, _delete_reservoir(name, cs))


#--------------------------------------------------------------
# [EPA2][EPA3][IN][OUT]
#   id elev (pattern) ;desc
#--------------------------------------------------------------


def inp_in_reservoir(line: str) -> str:
    tokens = line.split()

    num = len(tokens)
    has_desc = tokens[-1].startswith(';')
    num_without_desc = (num - 1) if has_desc else num

    id = str(tokens[0])
    head = float(tokens[1])
    pattern = str(tokens[2]) if num_without_desc >= 3 else None
    desc = str(tokens[-1]) if has_desc else None

    return str(f"insert into network.nodes (id, node_type) values ({sql_literal(id)}, 'reservoir');insert into network.reservoirs (node_id, head, pattern_id) values ({sql_literal(id)}, {sql_literal(head)}, {sql_literal(pattern)});")


def inp_out_reservoir(name: str) -> list[str]:
    lines = []
    objs = read_all(name, 'select node_id as id, head, pattern_id as pattern from network.reservoirs order by node_id')
    for obj in objs:
        id = obj['id']
        head = obj['head']
        pattern = obj['pattern'] if obj['pattern'] != None else ''
        desc = ';'
        lines.append(f'{id} {head} {pattern} {desc}')
    return lines


def unset_reservoir_by_pattern(name: str, pattern: str) -> ChangeSet:
    cs = ChangeSet()

    rows = read_all(name, "select node_id as id from network.reservoirs where pattern_id = %s", (pattern,))
    for row in rows:
        cs.append(g_update_prefix | {'type': 'reservoir', 'id': row['id'], 'pattern': None})

    return cs