import uuid
from pathlib import Path

import pytest
from sqlalchemy.ext.asyncio import AsyncSession

from src.models.config.config_profile import ConfigProfile, ConfigProfileInclude
from src.services.config.config_profile_resolver import (
    ConfigProfileCycleError,
    ConfigProfileNotFoundError,
    ResolvedMount,
    ResolvedProfile,
    apply_resolved_profile,
    check_include_cycle,
    resolve_profile,
    _merge_env_vars,
    _merge_files,
    _merge_mounts,
    _merge_runtime_hints,
    _merge_git_mounts,
)


class TestMergeFunctions:
    """Unit tests for merge helper functions."""

    def test_merge_env_vars_basic(self) -> None:
        """Test basic env var merging."""
        result = _merge_env_vars(
            {"A": "1", "B": "2"},
            {"B": "3", "C": "4"},
            {},
            "source",
        )
        assert result == {"A": "1", "B": "3", "C": "4"}

    def test_merge_env_vars_tracks_overrides(self) -> None:
        """Test that env var overrides are tracked."""
        overrides = {}
        _merge_env_vars(
            {"A": "1"},
            {"A": "2"},
            overrides,
            "source",
        )
        assert overrides == {"A": "source"}

    def test_merge_runtime_hints_basic(self) -> None:
        """Test basic runtime hint merging."""
        result = _merge_runtime_hints(
            {"command": "old"},
            {"command": "new", "port": 8080},
            {},
            "source",
        )
        assert result == {"command": "new", "port": 8080}

    def test_merge_files_basic(self) -> None:
        """Test basic file merging."""
        result = _merge_files(
            {"a.txt": "old"},
            {"a.txt": "new", "b.txt": "content"},
            {},
            "source",
        )
        assert result == {"a.txt": "new", "b.txt": "content"}

    def test_merge_mounts_basic(self) -> None:
        """Test basic mount merging."""
        result = _merge_mounts(
            {},
            [{"target": "/app", "mode": "rw", "files": {"a.txt": "content"}}],
            {},
            "source",
        )
        assert "/app" in result
        assert result["/app"].mode == "rw"
        assert result["/app"].files == {"a.txt": "content"}

    def test_merge_mounts_file_override(self) -> None:
        """Test mount file map merging with overrides."""
        from src.services.config.config_profile_resolver import ResolvedMount

        result = _merge_mounts(
            {"/app": ResolvedMount(target="/app", mode="rw", files={"a.txt": "old"})},
            [{"target": "/app", "mode": "rw", "files": {"a.txt": "new"}}],
            {},
            "source",
        )
        assert result["/app"].files == {"a.txt": "new"}

    def test_merge_mounts_mode_conflict(self) -> None:
        """Test that mount mode conflicts are resolved (later wins)."""
        from src.services.config.config_profile_resolver import ResolvedMount

        overrides = {}
        result = _merge_mounts(
            {"/app": ResolvedMount(target="/app", mode="rw", files={})},
            [{"target": "/app", "mode": "ro", "files": {}}],
            overrides,
            "source",
        )
        assert result["/app"].mode == "ro"
        assert overrides == {"/app": "source"}

    def test_merge_git_mounts_basic(self) -> None:
        """Test basic git mount merging normalizes to mappings format."""
        result = _merge_git_mounts(
            [],
            [
                {
                    "remote_url": "https://github.com/user/repo1.git",
                    "source_path": ".",
                    "target_path": "/app",
                }
            ],
            "source",
        )
        assert len(result) == 1
        assert result[0]["remote_url"] == "https://github.com/user/repo1.git"
        assert "mappings" in result[0]
        assert result[0]["mappings"] == [{"source_path": ".", "target_path": "/app"}]

    def test_merge_git_mounts_concatenate_same_repo_branch(self) -> None:
        """Test that git mounts with same repo+branch concatenate mappings."""
        result = _merge_git_mounts(
            [
                {
                    "remote_url": "https://github.com/user/repo1.git",
                    "source_path": ".",
                    "target_path": "/app",
                    "branch": "main",
                }
            ],
            [
                {
                    "remote_url": "https://github.com/user/repo1.git",
                    "source_path": "src",
                    "target_path": "/src",
                    "branch": "main",
                }
            ],
            "source",
        )
        assert len(result) == 1
        assert result[0]["branch"] == "main"
        mappings: list[dict[str, str]] = result[0]["mappings"]
        assert len(mappings) == 2
        assert {"source_path": ".", "target_path": "/app"} in mappings
        assert {"source_path": "src", "target_path": "/src"} in mappings

    def test_merge_git_mounts_dedup_same_mapping(self) -> None:
        """Test that duplicate mappings are deduplicated."""
        result = _merge_git_mounts(
            [
                {
                    "remote_url": "https://github.com/user/repo1.git",
                    "source_path": ".",
                    "target_path": "/app",
                    "branch": "main",
                }
            ],
            [
                {
                    "remote_url": "https://github.com/user/repo1.git",
                    "source_path": ".",
                    "target_path": "/app",
                    "branch": "main",
                }
            ],
            "source",
        )
        assert len(result) == 1
        assert len(result[0]["mappings"]) == 1

    def test_merge_git_mounts_different_repos(self) -> None:
        """Test that git mounts with different repos are preserved."""
        result = _merge_git_mounts(
            [
                {
                    "remote_url": "https://github.com/user/repo1.git",
                    "source_path": ".",
                    "target_path": "/app",
                }
            ],
            [
                {
                    "remote_url": "https://github.com/user/repo2.git",
                    "source_path": ".",
                    "target_path": "/config",
                }
            ],
            "source",
        )
        assert len(result) == 2
        urls = {m["remote_url"] for m in result}
        assert urls == {
            "https://github.com/user/repo1.git",
            "https://github.com/user/repo2.git",
        }

    def test_merge_git_mounts_different_branches(self) -> None:
        """Test that same repo with different branches are kept separate."""
        result = _merge_git_mounts(
            [
                {
                    "remote_url": "https://github.com/user/repo1.git",
                    "source_path": ".",
                    "target_path": "/app",
                    "branch": "main",
                }
            ],
            [
                {
                    "remote_url": "https://github.com/user/repo1.git",
                    "source_path": ".",
                    "target_path": "/app",
                    "branch": "dev",
                }
            ],
            "source",
        )
        assert len(result) == 2
        branches = {m.get("branch") for m in result}
        assert branches == {"main", "dev"}


class TestResolveProfile:
    """Unit tests for profile resolution."""

    @pytest.mark.asyncio
    async def test_resolve_simple_profile(self, db_session: AsyncSession) -> None:
        """Test resolving a profile with no includes."""
        user_id = uuid.uuid4()
        profile = ConfigProfile(
            id=uuid.uuid4(),
            user_id=user_id,
            name="simple",
            env_vars={"VAR": "value"},
            runtime_hints={"command": "run"},
            files={"test.txt": "content"},
            mounts=[{"target": "/app", "mode": "rw", "files": {}}],
        )
        db_session.add(profile)
        await db_session.commit()

        result = await resolve_profile(db_session, profile.id)
        assert result.profile_name == "simple"
        assert result.env_vars == {"VAR": "value"}
        assert result.runtime_hints == {"command": "run"}
        assert result.files == {"test.txt": "content"}

    @pytest.mark.asyncio
    async def test_resolve_profile_with_includes(
        self, db_session: AsyncSession
    ) -> None:
        """Test resolving a profile that includes another."""
        user_id = uuid.uuid4()

        # Create base profile
        base = ConfigProfile(
            id=uuid.uuid4(),
            user_id=user_id,
            name="base",
            env_vars={"BASE_VAR": "base_value"},
            files={},
        )
        db_session.add(base)

        # Create child profile
        child = ConfigProfile(
            id=uuid.uuid4(),
            user_id=user_id,
            name="child",
            env_vars={"CHILD_VAR": "child_value"},
            files={},
        )
        db_session.add(child)
        await db_session.commit()

        # Create include relationship
        include = ConfigProfileInclude(
            id=uuid.uuid4(),
            profile_id=child.id,
            included_profile_id=base.id,
            order_index=0,
        )
        db_session.add(include)
        await db_session.commit()

        result = await resolve_profile(db_session, child.id)
        assert result.env_vars == {
            "BASE_VAR": "base_value",
            "CHILD_VAR": "child_value",
        }
        assert len(result.included_profiles) == 1
        assert result.included_profiles[0]["name"] == "base"

    @pytest.mark.asyncio
    async def test_resolve_profile_child_overrides_parent(
        self, db_session: AsyncSession
    ) -> None:
        """Test that child profile values override parent values."""
        user_id = uuid.uuid4()

        base = ConfigProfile(
            id=uuid.uuid4(),
            user_id=user_id,
            name="base",
            env_vars={"VAR": "base"},
            files={},
        )
        db_session.add(base)

        child = ConfigProfile(
            id=uuid.uuid4(),
            user_id=user_id,
            name="child",
            env_vars={"VAR": "child"},
            files={},
        )
        db_session.add(child)
        await db_session.commit()

        include = ConfigProfileInclude(
            id=uuid.uuid4(),
            profile_id=child.id,
            included_profile_id=base.id,
            order_index=0,
        )
        db_session.add(include)
        await db_session.commit()

        result = await resolve_profile(db_session, child.id)
        assert result.env_vars == {"VAR": "child"}
        assert result.env_overrides == {"VAR": "child"}

    @pytest.mark.asyncio
    async def test_resolve_profile_cycle_detection(
        self, db_session: AsyncSession
    ) -> None:
        """Test that cycles are detected during resolution."""
        user_id = uuid.uuid4()

        profile_a = ConfigProfile(
            id=uuid.uuid4(),
            user_id=user_id,
            name="a",
            env_vars={},
            files={},
        )
        db_session.add(profile_a)

        profile_b = ConfigProfile(
            id=uuid.uuid4(),
            user_id=user_id,
            name="b",
            env_vars={},
            files={},
        )
        db_session.add(profile_b)
        await db_session.commit()

        # A includes B
        include_ab = ConfigProfileInclude(
            id=uuid.uuid4(),
            profile_id=profile_a.id,
            included_profile_id=profile_b.id,
            order_index=0,
        )
        db_session.add(include_ab)

        # B includes A (creates cycle)
        include_ba = ConfigProfileInclude(
            id=uuid.uuid4(),
            profile_id=profile_b.id,
            included_profile_id=profile_a.id,
            order_index=0,
        )
        db_session.add(include_ba)
        await db_session.commit()

        with pytest.raises(ConfigProfileCycleError):
            await resolve_profile(db_session, profile_a.id)

    @pytest.mark.asyncio
    async def test_resolve_profile_with_git_mounts(
        self, db_session: AsyncSession
    ) -> None:
        """Test resolving a profile with git mounts normalizes to mappings."""
        user_id = uuid.uuid4()

        profile = ConfigProfile(
            id=uuid.uuid4(),
            user_id=user_id,
            name="with-git-mounts",
            env_vars={},
            files={},
            git_mounts=[
                {
                    "remote_url": "https://github.com/user/repo1.git",
                    "source_path": ".",
                    "target_path": "/app",
                },
            ],
        )
        db_session.add(profile)
        await db_session.commit()

        result = await resolve_profile(db_session, profile.id)
        assert len(result.git_mounts) == 1
        assert result.git_mounts[0]["remote_url"] == "https://github.com/user/repo1.git"
        assert "mappings" in result.git_mounts[0]
        assert result.git_mounts[0]["mappings"] == [
            {"source_path": ".", "target_path": "/app"}
        ]

    @pytest.mark.asyncio
    async def test_resolve_profile_with_git_mount_includes(
        self, db_session: AsyncSession
    ) -> None:
        """Test resolving a profile that includes another with git mounts."""
        user_id = uuid.uuid4()

        # Create base profile with git mount
        base = ConfigProfile(
            id=uuid.uuid4(),
            user_id=user_id,
            name="base",
            env_vars={},
            files={},
            git_mounts=[
                {
                    "remote_url": "https://github.com/user/repo1.git",
                    "source_path": ".",
                    "target_path": "/app",
                },
            ],
        )
        db_session.add(base)

        # Create child profile with its own git mount
        child = ConfigProfile(
            id=uuid.uuid4(),
            user_id=user_id,
            name="child",
            env_vars={},
            files={},
            git_mounts=[
                {
                    "remote_url": "https://github.com/user/repo2.git",
                    "source_path": "config",
                    "target_path": "/config",
                },
            ],
        )
        db_session.add(child)
        await db_session.commit()

        # Create include relationship
        include = ConfigProfileInclude(
            id=uuid.uuid4(),
            profile_id=child.id,
            included_profile_id=base.id,
            order_index=0,
        )
        db_session.add(include)
        await db_session.commit()

        result = await resolve_profile(db_session, child.id)
        assert len(result.git_mounts) == 2
        urls = {m["remote_url"] for m in result.git_mounts}
        assert urls == {
            "https://github.com/user/repo1.git",
            "https://github.com/user/repo2.git",
        }
        for m in result.git_mounts:
            assert "mappings" in m

    @pytest.mark.asyncio
    async def test_resolve_profile_not_found(self, db_session: AsyncSession) -> None:
        """Test resolving a non-existent profile."""
        with pytest.raises(ConfigProfileNotFoundError):
            await resolve_profile(db_session, uuid.uuid4())


class TestApplyResolvedProfile:
    """Unit tests for apply_resolved_profile directory-level mount behavior."""

    def test_mounts_directory_not_individual_files(self, tmp_path) -> None:
        """Each ResolvedMount should produce one directory-level bind mount."""
        resolved = ResolvedProfile(
            profile_id=uuid.uuid4(),
            profile_name="test",
            mounts={
                "/app": ResolvedMount(
                    target="/app",
                    mode="rw",
                    files={
                        "config.json": '{"key": "value"}',
                        "nested/file.txt": "hello",
                    },
                )
            },
        )
        env, files, volumes, hints = apply_resolved_profile(str(tmp_path), resolved)

        assert len(volumes) == 1
        assert volumes[0]["target"] == "/app"
        assert Path(volumes[0]["source"]).name == "app"
        assert Path(volumes[0]["source"]).is_dir()
        assert (Path(volumes[0]["source"]) / "config.json").exists()
        assert (Path(volumes[0]["source"]) / "nested" / "file.txt").exists()

    def test_directory_mount_target(self, tmp_path) -> None:
        """A directory-level mount targets the configured directory path."""
        resolved = ResolvedProfile(
            profile_id=uuid.uuid4(),
            profile_name="test",
            mounts={
                "/workspace/x/y": ResolvedMount(
                    target="/workspace/x/y",
                    mode="rw",
                    files={"z.json": "override"},
                )
            },
        )
        env, files, volumes, hints = apply_resolved_profile(str(tmp_path), resolved)

        assert len(volumes) == 1
        assert volumes[0]["target"] == "/workspace/x/y"
        assert Path(volumes[0]["source"]).name == "workspace_x_y"
        assert (Path(volumes[0]["source"]) / "z.json").exists()

    def test_top_level_files_use_profile_scoped_direct_bind_mounts(self, tmp_path) -> None:
        """Top-level files are shared safely without mounting over a workspace."""
        profile_id = uuid.uuid4()
        resolved = ResolvedProfile(
            profile_id=profile_id,
            profile_name="test",
            files={".tool/config.toml": "setting = true"},
        )

        instance_root = tmp_path / "instances"
        _, files, volumes, _ = apply_resolved_profile(
            str(instance_root / "instance-a"),
            resolved,
            working_dir="/workspace/project",
        )

        canonical_file = (
            instance_root / "config-profiles" / str(profile_id) / "files" / ".tool" / "config.toml"
        )
        assert files == {}
        assert volumes == [
            {
                "source": str(canonical_file),
                "target": "/workspace/project/.tool/config.toml",
                "type": "bind",
                "readonly": False,
            }
        ]
        assert canonical_file.read_text() == "setting = true"

    def test_instances_share_profile_scoped_mount_sources(self, tmp_path) -> None:
        """Different instance paths resolve a profile to one canonical source."""
        profile_id = uuid.uuid4()
        resolved = ResolvedProfile(
            profile_id=profile_id,
            profile_name="test",
            mounts={"/app": ResolvedMount(target="/app", mode="rw", files={"config.ini": "x"})},
        )

        instance_root = tmp_path / "instances"
        _, _, first_volumes, _ = apply_resolved_profile(str(instance_root / "instance-a"), resolved)
        _, _, second_volumes, _ = apply_resolved_profile(str(instance_root / "instance-b"), resolved)

        assert first_volumes[0]["source"] == second_volumes[0]["source"]
        assert first_volumes[0]["source"] == str(
            instance_root / "config-profiles" / str(profile_id) / "mounts" / "app"
        )

    def test_empty_mount_produces_no_volumes(self, tmp_path) -> None:
        """A mount with no files should not produce any volume entries."""
        resolved = ResolvedProfile(
            profile_id=uuid.uuid4(),
            profile_name="test",
            mounts={"/app": ResolvedMount(target="/app", mode="rw", files={})},
        )
        env, files, volumes, hints = apply_resolved_profile(str(tmp_path), resolved)
        assert volumes == []

    def test_home_expansion_in_directory_mount_target(self, tmp_path) -> None:
        """~ in mount target should be expanded to home_dir for directory mounts."""
        resolved = ResolvedProfile(
            profile_id=uuid.uuid4(),
            profile_name="test",
            mounts={
                "~/.config": ResolvedMount(
                    target="~/.config",
                    mode="rw",
                    files={"app.toml": "setting = 1"},
                )
            },
        )
        env, files, volumes, hints = apply_resolved_profile(
            str(tmp_path), resolved, home_dir="/home/user"
        )
        assert len(volumes) == 1
        assert volumes[0]["target"] == "/home/user/.config"
        assert (Path(volumes[0]["source"]) / "app.toml").exists()

    def test_readonly_mount_sets_readonly_flag(self, tmp_path) -> None:
        """A mount with mode 'ro' should set readonly on the volume entry."""
        resolved = ResolvedProfile(
            profile_id=uuid.uuid4(),
            profile_name="test",
            mounts={
                "/etc/app": ResolvedMount(
                    target="/etc/app",
                    mode="ro",
                    files={"config.cfg": "value"},
                )
            },
        )
        env, files, volumes, hints = apply_resolved_profile(str(tmp_path), resolved)

        assert len(volumes) == 1
        assert volumes[0]["target"] == "/etc/app"
        assert volumes[0].get("readonly")

    def test_writable_mount_does_not_set_readonly_flag(self, tmp_path) -> None:
        """A mount with mode 'rw' should not set readonly on the volume entry."""
        resolved = ResolvedProfile(
            profile_id=uuid.uuid4(),
            profile_name="test",
            mounts={
                "/app": ResolvedMount(
                    target="/app",
                    mode="rw",
                    files={"config.json": "{}"},
                )
            },
        )
        env, files, volumes, hints = apply_resolved_profile(str(tmp_path), resolved)

        assert len(volumes) == 1
        assert volumes[0]["target"] == "/app"
        assert not volumes[0].get("readonly")


class TestCheckIncludeCycle:
    """Unit tests for include cycle checking."""

    @pytest.mark.asyncio
    async def test_check_no_cycle(self, db_session: AsyncSession) -> None:
        """Test checking when no cycle exists."""
        user_id = uuid.uuid4()

        profile_a = ConfigProfile(
            id=uuid.uuid4(),
            user_id=user_id,
            name="a",
            env_vars={},
            files={},
        )
        db_session.add(profile_a)

        profile_b = ConfigProfile(
            id=uuid.uuid4(),
            user_id=user_id,
            name="b",
            env_vars={},
            files={},
        )
        db_session.add(profile_b)
        await db_session.commit()

        # A includes B
        include = ConfigProfileInclude(
            id=uuid.uuid4(),
            profile_id=profile_a.id,
            included_profile_id=profile_b.id,
            order_index=0,
        )
        db_session.add(include)
        await db_session.commit()

        result = await check_include_cycle(db_session, profile_a.id)
        assert result is None

    @pytest.mark.asyncio
    async def test_check_detects_cycle(self, db_session: AsyncSession) -> None:
        """Test detecting an existing cycle."""
        user_id = uuid.uuid4()

        profile_a = ConfigProfile(
            id=uuid.uuid4(),
            user_id=user_id,
            name="a",
            env_vars={},
            files={},
        )
        db_session.add(profile_a)

        profile_b = ConfigProfile(
            id=uuid.uuid4(),
            user_id=user_id,
            name="b",
            env_vars={},
            files={},
        )
        db_session.add(profile_b)
        await db_session.commit()

        # A includes B
        include_ab = ConfigProfileInclude(
            id=uuid.uuid4(),
            profile_id=profile_a.id,
            included_profile_id=profile_b.id,
            order_index=0,
        )
        db_session.add(include_ab)

        # B includes A
        include_ba = ConfigProfileInclude(
            id=uuid.uuid4(),
            profile_id=profile_b.id,
            included_profile_id=profile_a.id,
            order_index=0,
        )
        db_session.add(include_ba)
        await db_session.commit()

        result = await check_include_cycle(db_session, profile_a.id)
        assert result is not None
        assert len(result) > 1

    @pytest.mark.asyncio
    async def test_check_would_create_cycle(self, db_session: AsyncSession) -> None:
        """Test detecting a cycle that would be created."""
        user_id = uuid.uuid4()

        profile_a = ConfigProfile(
            id=uuid.uuid4(),
            user_id=user_id,
            name="a",
            env_vars={},
            files={},
        )
        db_session.add(profile_a)

        profile_b = ConfigProfile(
            id=uuid.uuid4(),
            user_id=user_id,
            name="b",
            env_vars={},
            files={},
        )
        db_session.add(profile_b)
        await db_session.commit()

        # A includes B
        include = ConfigProfileInclude(
            id=uuid.uuid4(),
            profile_id=profile_a.id,
            included_profile_id=profile_b.id,
            order_index=0,
        )
        db_session.add(include)
        await db_session.commit()

        # Check if adding B includes A would create cycle
        result = await check_include_cycle(db_session, profile_b.id, profile_a.id)
        assert result is not None