import uuid

from django.conf import settings
from django.db import models
from django.db.models import Q


class ModelProvider(models.Model):
    name = models.CharField(max_length=120)
    base_url = models.URLField(max_length=500)
    api_key_encrypted = models.TextField(blank=True)
    enabled = models.BooleanField(default=True)
    default_timeout_seconds = models.PositiveIntegerField(default=60)
    image_egress_approved = models.BooleanField(default=False)
    image_egress_approved_by = models.ForeignKey(
        settings.AUTH_USER_MODEL,
        null=True,
        blank=True,
        on_delete=models.SET_NULL,
        related_name="approved_image_model_providers",
    )
    image_egress_approved_at = models.DateTimeField(null=True, blank=True)
    credential_updated_at = models.DateTimeField(null=True, blank=True)
    credential_updated_by = models.ForeignKey(
        settings.AUTH_USER_MODEL,
        null=True,
        blank=True,
        on_delete=models.SET_NULL,
        related_name="updated_model_provider_credentials",
    )
    archived_at = models.DateTimeField(null=True, blank=True, db_index=True)
    archived_by = models.ForeignKey(
        settings.AUTH_USER_MODEL,
        null=True,
        blank=True,
        on_delete=models.SET_NULL,
        related_name="archived_model_providers",
    )
    created_by = models.ForeignKey(
        settings.AUTH_USER_MODEL,
        null=True,
        blank=True,
        on_delete=models.SET_NULL,
        related_name="created_model_providers",
    )
    created_at = models.DateTimeField(auto_now_add=True)
    updated_at = models.DateTimeField(auto_now=True)

    class Meta:
        ordering = ["name"]
        constraints = [
            models.UniqueConstraint(
                fields=["name"],
                condition=Q(archived_at__isnull=True),
                name="unique_active_model_provider_name",
            )
        ]


class ModelDeployment(models.Model):
    class StructuredOutputMode(models.TextChoices):
        UNCONFIGURED = "unconfigured", "未配置"
        NATIVE_JSON_SCHEMA = "native_json_schema", "原生 JSON Schema"
        JSON_OBJECT = "json_object", "JSON Object"
        PROMPT_SCHEMA = "prompt_schema", "Prompt Schema"
        NONE = "none", "不支持"

    class StructuredOutputTestStatus(models.TextChoices):
        UNTESTED = "untested", "未验证"
        PASSED = "passed", "已通过"
        FAILED = "failed", "验证失败"

    provider = models.ForeignKey(
        ModelProvider,
        on_delete=models.PROTECT,
        related_name="deployments",
    )
    display_name = models.CharField(max_length=120)
    model_name = models.CharField(max_length=160)
    capability = models.CharField(max_length=40, default="text_chat")
    default_temperature = models.FloatField(default=0.2)
    max_output_tokens = models.PositiveIntegerField(default=2048)
    structured_output_mode = models.CharField(
        max_length=32,
        choices=StructuredOutputMode.choices,
        default=StructuredOutputMode.UNCONFIGURED,
    )
    structured_output_test_status = models.CharField(
        max_length=16,
        choices=StructuredOutputTestStatus.choices,
        default=StructuredOutputTestStatus.UNTESTED,
    )
    structured_output_verified_at = models.DateTimeField(null=True, blank=True)
    structured_output_test_message = models.TextField(blank=True)
    enabled = models.BooleanField(default=True)
    archived_at = models.DateTimeField(null=True, blank=True, db_index=True)
    archived_by = models.ForeignKey(
        settings.AUTH_USER_MODEL,
        null=True,
        blank=True,
        on_delete=models.SET_NULL,
        related_name="archived_model_deployments",
    )
    archived_via_provider = models.BooleanField(default=False)
    created_at = models.DateTimeField(auto_now_add=True)
    updated_at = models.DateTimeField(auto_now=True)

    class Meta:
        ordering = ["provider__name", "display_name"]
        constraints = [
            models.UniqueConstraint(
                fields=["provider", "model_name"],
                condition=Q(archived_at__isnull=True),
                name="unique_active_provider_model_name",
            )
        ]


class ModelInvocation(models.Model):
    public_id = models.UUIDField(default=uuid.uuid4, unique=True, editable=False)
    deployment = models.ForeignKey(
        ModelDeployment,
        null=True,
        blank=True,
        on_delete=models.SET_NULL,
        related_name="invocations",
    )
    invocation_type = models.CharField(max_length=40, default="model_test")
    status = models.CharField(max_length=24, default="queued")
    model_snapshot = models.JSONField(default=dict, blank=True)
    input_snapshot = models.JSONField(default=dict, blank=True)
    output_text = models.TextField(blank=True)
    input_tokens = models.PositiveIntegerField(null=True, blank=True)
    output_tokens = models.PositiveIntegerField(null=True, blank=True)
    duration_ms = models.PositiveIntegerField(default=0)
    retry_count = models.PositiveIntegerField(default=0)
    error_code = models.CharField(max_length=80, blank=True)
    error_message = models.TextField(blank=True)
    diagnostics_scrubbed_at = models.DateTimeField(null=True, blank=True)
    created_by = models.ForeignKey(
        settings.AUTH_USER_MODEL,
        null=True,
        blank=True,
        on_delete=models.SET_NULL,
        related_name="model_invocations",
    )
    created_at = models.DateTimeField(auto_now_add=True)
    started_at = models.DateTimeField(null=True, blank=True)
    finished_at = models.DateTimeField(null=True, blank=True)

    class Meta:
        ordering = ["-created_at"]
        indexes = [
            models.Index(fields=["status", "created_at"]),
            models.Index(fields=["invocation_type", "created_at"]),
            models.Index(fields=["deployment", "created_at"]),
        ]