from __future__ import annotations

import copy
import hashlib
import json
import os
import shutil
import sqlite3
import tempfile
import unittest
from dataclasses import replace
from pathlib import Path
from unittest import mock

from docforge.errors import DocForgeError
from docforge.manual_projection import (
    build_manual_projection_package,
    build_manual_render_plan,
)
from docforge.models import Edge
from docforge.project import Project
from docforge.projection_contract import (
    MANUAL_RENDER_PLAN_CONTRACT,
    PROJECTION_PACKAGE_CONTRACT,
    PROJECTION_RECEIPT_CONTRACT,
    ManualRenderPlanV1,
    ProjectionArtifact,
    ProjectionPackageV1,
    ProjectionReceiptV1,
    canonical_projection_bytes,
    projection_hash,
)
from docforge.render_contract import GenericHtmlRenderer
from docforge_renderers.manual import ManualHtmlRenderer

ROOT = Path(__file__).resolve().parents[1]
FIXTURES = ROOT / "tests" / "fixtures"

ALPHA_RENDERER_VERSION = "1+markdown-it-py-4.2.0"
ALPHA_RENDER_IDENTITY = "1c0a49c28ba3b0dabf94be36e75def197dee1be3cb73ac405b09875383c8dc5f"
ALPHA_OUTPUT_HASH = "81656bb89debc7ad1fbe8bc290e9a3ba90664442b17a6d57e908d30d20c47f77"
ALPHA_OUTPUT_BYTES = 2043


class ProjectionContractTests(unittest.TestCase):
    def setUp(self) -> None:
        self.temporary = tempfile.TemporaryDirectory()
        self.addCleanup(self.temporary.cleanup)
        self.root = Path(self.temporary.name) / "alpha"
        shutil.copytree(FIXTURES / "alpha", self.root)
        self.project = Project.open(self.root)
        self.snapshot = self.project.load()
        assert self.snapshot.descriptor.render is not None
        self.view = self.snapshot.descriptor.render.views[0]
        self.template = self.view.template_path.read_bytes()
        self.plan = build_manual_render_plan(
            self.snapshot,
            self.view,
            changeset_hash=None,
        )
        self.package = build_manual_projection_package(
            self.plan,
            self.template,
            renderer_id="generic_html",
            renderer_version=ALPHA_RENDERER_VERSION,
            max_output_bytes=self.snapshot.descriptor.limits.max_render_bytes,
        )

    def test_canonical_identity_is_stable_and_tampering_is_rejected(self) -> None:
        self.assertEqual(
            b'{"a":"\xc3\xa9","b":1}',
            canonical_projection_bytes({"b": 1, "a": "\N{LATIN SMALL LETTER E WITH ACUTE}"}),
        )
        self.assertEqual(
            projection_hash(
                {key: value for key, value in self.plan.as_dict().items() if key != "plan_id"}
            ),
            self.plan.plan_id,
        )
        self.assertEqual(
            self.plan.plan_id,
            build_manual_render_plan(
                self.snapshot,
                self.view,
                changeset_hash=None,
            ).plan_id,
        )
        self.assertEqual(
            self.package.package_id,
            ProjectionPackageV1.from_dict(
                json.loads(json.dumps(self.package.as_dict()))
            ).package_id,
        )

        tampered_plan = copy.deepcopy(self.plan.as_dict())
        pages = tampered_plan["pages"]
        assert isinstance(pages, list)
        assert isinstance(pages[0], dict)
        pages[0]["title"] = "Tampered title"
        with self.assertRaises(DocForgeError) as plan_error:
            ManualRenderPlanV1.from_dict(tampered_plan)
        self.assertEqual("invalid_projection", plan_error.exception.code)

        tampered_package = copy.deepcopy(self.package.as_dict())
        assets = tampered_package["assets"]
        assert isinstance(assets, list)
        assert isinstance(assets[0], dict)
        assets[0]["text"] = f"{assets[0]['text']}\nTampered"
        with self.assertRaises(DocForgeError) as package_error:
            ProjectionPackageV1.from_dict(tampered_package)
        self.assertEqual("invalid_projection", package_error.exception.code)

    def test_contract_documents_reject_unknown_or_malformed_fields(self) -> None:
        plan_with_extra = copy.deepcopy(self.plan.as_dict())
        plan_with_extra["unexpected"] = True
        with self.assertRaises(DocForgeError) as extra_plan:
            ManualRenderPlanV1.from_dict(plan_with_extra)
        self.assertEqual("invalid_projection", extra_plan.exception.code)

        plan_with_foreign_project = copy.deepcopy(self.plan.as_dict())
        project = plan_with_foreign_project["project"]
        assert isinstance(project, dict)
        project["absolute_root"] = str(self.root)
        with self.assertRaises(DocForgeError) as foreign_project:
            ManualRenderPlanV1.from_dict(plan_with_foreign_project)
        self.assertEqual("invalid_projection", foreign_project.exception.code)

        package_with_extra = copy.deepcopy(self.package.as_dict())
        package_with_extra["unexpected"] = []
        with self.assertRaises(DocForgeError) as extra_package:
            ProjectionPackageV1.from_dict(package_with_extra)
        self.assertEqual("invalid_projection", extra_package.exception.code)

        result = ManualHtmlRenderer(ALPHA_RENDERER_VERSION).render(self.package)
        receipt_with_extra = copy.deepcopy(result.receipt.as_dict())
        receipt_with_extra["artifact_bytes"] = "forbidden"
        with self.assertRaises(DocForgeError) as extra_receipt:
            ProjectionReceiptV1.from_dict(receipt_with_extra)
        self.assertEqual("invalid_projection", extra_receipt.exception.code)

        with self.assertRaises(DocForgeError) as path_artifact:
            ProjectionReceiptV1.create(
                kind="manual",
                package_id=self.package.package_id,
                plan_id=self.plan.plan_id,
                renderer={
                    "renderer_id": "generic_html",
                    "renderer_version": ALPHA_RENDERER_VERSION,
                },
                artifacts=[
                    {
                        "artifact_id": "../manual.html",
                        "media_type": "text/html",
                        "sha256": "0" * 64,
                        "bytes": 1,
                    }
                ],
                diagnostics={},
                timing={"elapsed_ns": 0},
                peak_memory_bytes=None,
            )
        self.assertEqual("invalid_projection", path_artifact.exception.code)

    def test_projection_package_is_path_free_and_rejects_runtime_references(self) -> None:
        serialized = canonical_projection_bytes(self.package.as_dict())
        self.assertNotIn(str(self.root).encode("utf-8"), serialized)
        self.assertNotIn(b"source_path", serialized)
        self.assertNotIn(b"sqlite", serialized.lower())

        with self.assertRaises(DocForgeError) as absolute_path:
            ProjectionPackageV1.create(
                kind="manual",
                plan=self.plan,
                renderer={
                    "renderer_id": "generic_html",
                    "renderer_version": ALPHA_RENDERER_VERSION,
                },
                components=[],
                assets=[],
                output_policy={
                    "artifact_ids": ["manual.html"],
                    "max_total_bytes": 1000,
                    "template_path": "/home/example/private-template.html",
                },
            )
        self.assertEqual("invalid_projection", absolute_path.exception.code)

        with self.assertRaises(DocForgeError) as database_reference:
            ProjectionPackageV1.create(
                kind="manual",
                plan=self.plan,
                renderer={
                    "renderer_id": "generic_html",
                    "renderer_version": ALPHA_RENDERER_VERSION,
                },
                components=[],
                assets=[],
                output_policy={
                    "artifact_ids": ["manual.html"],
                    "max_total_bytes": 1000,
                    "database": "index.sqlite3",
                },
            )
        self.assertEqual("invalid_projection", database_reference.exception.code)

    def test_receipt_attests_artifacts_without_embedding_content(self) -> None:
        result = ManualHtmlRenderer(ALPHA_RENDERER_VERSION).render(
            self.package,
            render_identity=ALPHA_RENDER_IDENTITY,
        )
        self.assertEqual(1, len(result.artifacts))
        artifact = result.artifacts[0]
        evidence = artifact.evidence()
        receipt = result.receipt.as_dict()

        self.assertEqual(self.package.package_id, receipt["package_id"])
        self.assertEqual(self.plan.plan_id, receipt["plan_id"])
        self.assertEqual([evidence], receipt["artifacts"])
        self.assertEqual(PROJECTION_RECEIPT_CONTRACT, receipt["contract"])
        self.assertEqual(
            {
                "renderer_id": "generic_html",
                "renderer_version": ALPHA_RENDERER_VERSION,
            },
            receipt["renderer"],
        )
        self.assertEqual({"warnings": []}, receipt["diagnostics"])
        self.assertIsNone(receipt["peak_memory_bytes"])
        timing = receipt["timing"]
        assert isinstance(timing, dict)
        self.assertGreaterEqual(timing["elapsed_ns"], 0)
        self.assertNotIn("content", evidence)
        self.assertNotIn(artifact.content, canonical_projection_bytes(receipt))
        self.assertEqual(
            receipt["receipt_id"],
            ProjectionReceiptV1.from_dict(copy.deepcopy(receipt)).receipt_id,
        )

        tampered_receipt = copy.deepcopy(receipt)
        artifacts = tampered_receipt["artifacts"]
        assert isinstance(artifacts, list)
        assert isinstance(artifacts[0], dict)
        artifacts[0]["bytes"] = int(artifacts[0]["bytes"]) + 1
        with self.assertRaises(DocForgeError) as tampered:
            ProjectionReceiptV1.from_dict(tampered_receipt)
        self.assertEqual("invalid_projection", tampered.exception.code)

    def test_manual_plan_is_deterministic_and_preserves_alpha_semantics(self) -> None:
        document = self.plan.as_dict()
        self.assertEqual(MANUAL_RENDER_PLAN_CONTRACT, document["contract"])
        self.assertIsNone(document["changeset_hash"])
        pages = document["pages"]
        navigation = document["navigation"]
        search_documents = document["search_documents"]
        diagnostics = document["diagnostics"]
        assert isinstance(pages, list)
        assert isinstance(navigation, list)
        assert isinstance(search_documents, list)
        assert isinstance(diagnostics, dict)

        self.assertEqual(
            ["guide.foundation", "guide.workflow", "proof.validation"],
            [page["node_id"] for page in pages],
        )
        self.assertEqual(
            ["guide.foundation", "guide.workflow", "proof.validation"],
            [item["node_id"] for item in navigation],
        )
        self.assertEqual(
            ["guide.foundation", "guide.workflow", "proof.validation"],
            [item["node_id"] for item in search_documents],
        )
        self.assertEqual([], diagnostics["orphans"])
        self.assertEqual([], diagnostics["cycles"])

        page_by_id = {page["node_id"]: page for page in pages}
        self.assertEqual(
            [
                {
                    "source_id": "guide.workflow",
                    "relation": "depends_on",
                    "target_id": "guide.foundation",
                }
            ],
            page_by_id["guide.foundation"]["backlinks"],
        )
        self.assertEqual(
            [
                {
                    "source_id": "guide.workflow",
                    "relation": "depends_on",
                    "target_id": "guide.foundation",
                }
            ],
            page_by_id["guide.workflow"]["cross_references"],
        )
        self.assertEqual(
            [
                {
                    "source_id": "proof.validation",
                    "relation": "proves",
                    "target_id": "guide.workflow",
                }
            ],
            page_by_id["guide.workflow"]["backlinks"],
        )
        self.assertEqual(
            [
                {
                    "source_id": "proof.validation",
                    "relation": "proves",
                    "target_id": "guide.workflow",
                }
            ],
            page_by_id["proof.validation"]["cross_references"],
        )
        self.assertTrue(
            all(
                page["components"]
                == [
                    "manual.node-metadata@1",
                    "manual.summary@1",
                    "manual.commonmark@1",
                    "manual.relationships@1",
                ]
                for page in pages
            )
        )

        proposed = build_manual_render_plan(
            self.snapshot,
            self.view,
            changeset_hash="a" * 64,
        )
        self.assertNotEqual(self.plan.plan_id, proposed.plan_id)
        self.assertEqual("a" * 64, proposed.as_dict()["changeset_hash"])

    def test_cycle_orphan_backlink_and_cross_reference_planning(self) -> None:
        edges = (
            Edge("guide.foundation", "relates_to", "guide.workflow"),
            Edge("guide.workflow", "returns_to", "guide.foundation"),
        )
        snapshot = replace(self.snapshot, edges=edges)
        first = build_manual_render_plan(snapshot, self.view, changeset_hash=None)
        second = build_manual_render_plan(snapshot, self.view, changeset_hash=None)
        self.assertEqual(first.plan_id, second.plan_id)

        document = first.as_dict()
        diagnostics = document["diagnostics"]
        pages = document["pages"]
        assert isinstance(diagnostics, dict)
        assert isinstance(pages, list)
        self.assertEqual(["proof.validation"], diagnostics["orphans"])
        self.assertEqual(
            [["guide.foundation", "guide.workflow"]],
            diagnostics["cycles"],
        )

        page_by_id = {page["node_id"]: page for page in pages}
        foundation = page_by_id["guide.foundation"]
        workflow = page_by_id["guide.workflow"]
        self.assertEqual(
            [
                {
                    "source_id": "guide.foundation",
                    "relation": "relates_to",
                    "target_id": "guide.workflow",
                }
            ],
            foundation["cross_references"],
        )
        self.assertEqual(
            [
                {
                    "source_id": "guide.workflow",
                    "relation": "returns_to",
                    "target_id": "guide.foundation",
                }
            ],
            foundation["backlinks"],
        )
        self.assertEqual(
            foundation["cross_references"],
            workflow["backlinks"],
        )
        self.assertEqual(
            foundation["backlinks"],
            workflow["cross_references"],
        )

    def test_alpha_compatibility_shim_preserves_legacy_identity_and_bytes(self) -> None:
        renderer = GenericHtmlRenderer()
        self.assertEqual(ALPHA_RENDERER_VERSION, renderer.renderer_version)
        prepared = renderer.prepare(
            self.snapshot,
            self.view,
            self.template,
            changeset_hash=None,
        )

        self.assertEqual(ALPHA_RENDER_IDENTITY, prepared.render_identity)
        self.assertEqual(ALPHA_OUTPUT_HASH, prepared.output_hash)
        self.assertEqual(ALPHA_OUTPUT_BYTES, len(prepared.output))
        self.assertEqual(
            ALPHA_OUTPUT_HASH,
            hashlib.sha256(prepared.output).hexdigest(),
        )
        self.assertEqual(b"<!DOCTYPE html>", prepared.output.splitlines()[0])
        self.assertTrue(prepared.output.endswith(b"</html>\n"))
        self.assertIn(
            f'content="{ALPHA_RENDER_IDENTITY}"'.encode(),
            prepared.output,
        )

    def test_manual_renderer_rejects_project_provided_active_content(self) -> None:
        for active in (
            "<script>alert(1)</script>{{ docforge_content }}",
            '<main onclick="alert(1)">{{ docforge_content }}</main>',
            '<a href="javascript:alert(1)">{{ docforge_content }}</a>',
            '<iframe src="https://example.invalid"></iframe>{{ docforge_content }}',
            '<meta http-equiv="refresh" content="0">{{ docforge_content }}',
        ):
            with self.subTest(active=active):
                package = build_manual_projection_package(
                    self.plan,
                    active.encode("utf-8"),
                    renderer_id="generic_html",
                    renderer_version=ALPHA_RENDERER_VERSION,
                    max_output_bytes=self.snapshot.descriptor.limits.max_render_bytes,
                )
                with self.assertRaises(DocForgeError) as rejected:
                    ManualHtmlRenderer(ALPHA_RENDERER_VERSION).render(package)
                self.assertEqual("invalid_template", rejected.exception.code)

    def test_manual_renderer_has_no_project_sqlite_or_path_write_capability(self) -> None:
        renderer = ManualHtmlRenderer(ALPHA_RENDERER_VERSION)
        forbidden = AssertionError("manual renderer crossed its capability boundary")
        with (
            mock.patch.object(Project, "open", side_effect=forbidden),
            mock.patch.object(Project, "load", side_effect=forbidden),
            mock.patch.object(sqlite3, "connect", side_effect=forbidden),
            mock.patch.object(Path, "write_bytes", side_effect=forbidden),
            mock.patch.object(Path, "write_text", side_effect=forbidden),
            mock.patch.object(Path, "mkdir", side_effect=forbidden),
            mock.patch.object(Path, "touch", side_effect=forbidden),
            mock.patch.object(Path, "unlink", side_effect=forbidden),
            mock.patch.object(Path, "rename", side_effect=forbidden),
            mock.patch.object(Path, "replace", side_effect=forbidden),
            mock.patch.object(os, "mkdir", side_effect=forbidden),
            mock.patch.object(os, "makedirs", side_effect=forbidden),
            mock.patch.object(os, "rename", side_effect=forbidden),
            mock.patch.object(os, "replace", side_effect=forbidden),
            mock.patch.object(os, "unlink", side_effect=forbidden),
        ):
            result = renderer.render(
                self.package,
                render_identity=ALPHA_RENDER_IDENTITY,
            )

        self.assertEqual(1, len(result.artifacts))
        self.assertEqual("manual.html", result.artifacts[0].artifact_id)
        self.assertEqual(ALPHA_OUTPUT_HASH, result.artifacts[0].evidence()["sha256"])

    def test_projection_artifact_evidence_is_canonical_and_content_free(self) -> None:
        artifact = ProjectionArtifact(
            artifact_id="manual.html",
            media_type="text/html; charset=utf-8",
            content=b"manual bytes",
        )
        self.assertEqual(
            {
                "artifact_id": "manual.html",
                "media_type": "text/html; charset=utf-8",
                "sha256": hashlib.sha256(b"manual bytes").hexdigest(),
                "bytes": len(b"manual bytes"),
            },
            artifact.evidence(),
        )
        self.assertEqual(
            PROJECTION_PACKAGE_CONTRACT,
            self.package.as_dict()["contract"],
        )


if __name__ == "__main__":
    unittest.main()