# Django 4.2.11 documentation

# Source code for django.contrib.postgres.indexes

    from django.db import NotSupportedError
    from django.db.models import Func, Index
    from django.utils.functional import cached_property

    __all__ = [
        "BloomIndex",
        "BrinIndex",
        "BTreeIndex",
        "GinIndex",
        "GistIndex",
        "HashIndex",
        "SpGistIndex",
    ]

    class PostgresIndex(Index):
        @cached_property
        def max_name_length(self):
            # Allow an index name longer than 30 characters when the suffix is
            # longer than the usual 3 character limit. The 30 character limit for
            # cross-database compatibility isn't applicable to PostgreSQL-specific
            # indexes.
            return Index.max_name_length - len(Index.suffix) + len(self.suffix)

        def create_sql(self, model, schema_editor, using="", **kwargs):
            self.check_supported(schema_editor)
            statement = super().create_sql(
                model, schema_editor, using=" USING %s" % (using or self.suffix), **kwargs
            )
            with_params = self.get_with_params()
            if with_params:
                statement.parts["extra"] = " WITH (%s)%s" % (
                    ", ".join(with_params),
                    statement.parts["extra"],
                )
            return statement

        def check_supported(self, schema_editor):
            pass

        def get_with_params(self):
            return []

    class BloomIndex(PostgresIndex):
        suffix = "bloom"

        def __init__(self, *expressions, length=None, columns=(), **kwargs):
            super().__init__(*expressions, **kwargs)
            if len(self.fields) > 32:
                raise ValueError("Bloom indexes support a maximum of 32 fields.")
            if not isinstance(columns, (list, tuple)):
                raise ValueError("BloomIndex.columns must be a list or tuple.")
            if len(columns) > len(self.fields):
                raise ValueError("BloomIndex.columns cannot have more values than fields.")
            if not all(0 < col <= 4095 for col in columns):
                raise ValueError(
                    "BloomIndex.columns must contain integers from 1 to 4095.",
                )
            if length is not None and not 0 < length <= 4096:
                raise ValueError(
                    "BloomIndex.length must be None or an integer from 1 to 4096.",
                )
            self.length = length
            self.columns = columns

        def deconstruct(self):
            path, args, kwargs = super().deconstruct()
            if self.length is not None:
                kwargs["length"] = self.length
            if self.columns:
                kwargs["columns"] = self.columns
            return path, args, kwargs

        def get_with_params(self):
            with_params = []
            if self.length is not None:
                with_params.append("length = %d" % self.length)
            if self.columns:
                with_params.extend(
                    "col%d = %d" % (i, v) for i, v in enumerate(self.columns, start=1)
                )
            return with_params

    class BrinIndex(PostgresIndex):
        suffix = "brin"

        def __init__(
            self, *expressions, autosummarize=None, pages_per_range=None, **kwargs
        ):
            if pages_per_range is not None and pages_per_range <= 0:
                raise ValueError("pages_per_range must be None or a positive integer")
            self.autosummarize = autosummarize
            self.pages_per_range = pages_per_range
            super().__init__(*expressions, **kwargs)

        def deconstruct(self):
            path, args, kwargs = super().deconstruct()
            if self.autosummarize is not None:
                kwargs["autosummarize"] = self.autosummarize
            if self.pages_per_range is not None:
                kwargs["pages_per_range"] = self.pages_per_range
            return path, args, kwargs

        def get_with_params(self):
            with_params = []
            if self.autosummarize is not None:
                with_params.append(
                    "autosummarize = %s" % ("on" if self.autosummarize else "off")
                )
            if self.pages_per_range is not None:
                with_params.append("pages_per_range = %d" % self.pages_per_range)
            return with_params

    class BTreeIndex(PostgresIndex):
        suffix = "btree"

        def __init__(self, *expressions, fillfactor=None, **kwargs):
            self.fillfactor = fillfactor
            super().__init__(*expressions, **kwargs)

        def deconstruct(self):
            path, args, kwargs = super().deconstruct()
            if self.fillfactor is not None:
                kwargs["fillfactor"] = self.fillfactor
            return path, args, kwargs

        def get_with_params(self):
            with_params = []
            if self.fillfactor is not None:
                with_params.append("fillfactor = %d" % self.fillfactor)
            return with_params

    class GinIndex(PostgresIndex):
        suffix = "gin"

        def __init__(
            self, *expressions, fastupdate=None, gin_pending_list_limit=None, **kwargs
        ):
            self.fastupdate = fastupdate
            self.gin_pending_list_limit = gin_pending_list_limit
            super().__init__(*expressions, **kwargs)

        def deconstruct(self):
            path, args, kwargs = super().deconstruct()
            if self.fastupdate is not None:
                kwargs["fastupdate"] = self.fastupdate
            if self.gin_pending_list_limit is not None:
                kwargs["gin_pending_list_limit"] = self.gin_pending_list_limit
            return path, args, kwargs

        def get_with_params(self):
            with_params = []
            if self.gin_pending_list_limit is not None:
                with_params.append(
                    "gin_pending_list_limit = %d" % self.gin_pending_list_limit
                )
            if self.fastupdate is not None:
                with_params.append("fastupdate = %s" % ("on" if self.fastupdate else "off"))
            return with_params

    class GistIndex(PostgresIndex):
        suffix = "gist"

        def __init__(self, *expressions, buffering=None, fillfactor=None, **kwargs):
            self.buffering = buffering
            self.fillfactor = fillfactor
            super().__init__(*expressions, **kwargs)

        def deconstruct(self):
            path, args, kwargs = super().deconstruct()
            if self.buffering is not None:
                kwargs["buffering"] = self.buffering
            if self.fillfactor is not None:
                kwargs["fillfactor"] = self.fillfactor
            return path, args, kwargs

        def get_with_params(self):
            with_params = []
            if self.buffering is not None:
                with_params.append("buffering = %s" % ("on" if self.buffering else "off"))
            if self.fillfactor is not None:
                with_params.append("fillfactor = %d" % self.fillfactor)
            return with_params

    class HashIndex(PostgresIndex):
        suffix = "hash"

        def __init__(self, *expressions, fillfactor=None, **kwargs):
            self.fillfactor = fillfactor
            super().__init__(*expressions, **kwargs)

        def deconstruct(self):
            path, args, kwargs = super().deconstruct()
            if self.fillfactor is not None:
                kwargs["fillfactor"] = self.fillfactor
            return path, args, kwargs

        def get_with_params(self):
            with_params = []
            if self.fillfactor is not None:
                with_params.append("fillfactor = %d" % self.fillfactor)
            return with_params

    class SpGistIndex(PostgresIndex):
        suffix = "spgist"

        def __init__(self, *expressions, fillfactor=None, **kwargs):
            self.fillfactor = fillfactor
            super().__init__(*expressions, **kwargs)

        def deconstruct(self):
            path, args, kwargs = super().deconstruct()
            if self.fillfactor is not None:
                kwargs["fillfactor"] = self.fillfactor
            return path, args, kwargs

        def get_with_params(self):
            with_params = []
            if self.fillfactor is not None:
                with_params.append("fillfactor = %d" % self.fillfactor)
            return with_params

        def check_supported(self, schema_editor):
            if (
                self.include
                and not schema_editor.connection.features.supports_covering_spgist_indexes
            ):
                raise NotSupportedError("Covering SP-GiST indexes require PostgreSQL 14+.")

    class OpClass(Func):
        template = "%(expressions)s %(name)s"

        def __init__(self, expression, name):
            super().__init__(expression, name=name)