#!/usr/bin/env python3
# Copyright 2025 Timothé Lapetite and contributors
# Released under the MIT license https://opensource.org/license/MIT/
# NOTE : This code was generated by Claude AI.

import json
import os
import re
import shutil
import sys
from pathlib import Path

PLUGIN_NAME = "PCGExtendedToolkit"
MODULE_PREFIX = "PCGEx"
EDITOR_SUFFIX = "Editor"

PLATFORMS = {
    "runtime": ["Win64", "Mac", "IOS", "Android", "Linux", "LinuxArm64"],
    "editor": ["Win64", "Mac", "Linux"],
}

# Resolve paths relative to script location (assumes script is in plugin root or Config/)
script_dir = Path(__file__).parent.resolve()
plugin_root = (
    script_dir
    if (script_dir / f"{PLUGIN_NAME}.uplugin").exists()
    else script_dir.parent
)

# Project root is typically two levels up from plugin (Plugins/PCGExtendedToolkit/)
project_root = plugin_root.parent.parent

PATHS = {
    "uplugin": plugin_root / f"{PLUGIN_NAME}.uplugin",
    "modules_dir": plugin_root / "Source",
    "binaries": plugin_root / "Binaries",
    "intermediate": plugin_root / "Intermediate",
    # Project-level config takes priority, falls back to plugin config
    "project_submodules_config": project_root / "Config" / "PCGExSubModulesConfig.ini",
    "plugin_submodules_config": plugin_root / "Config" / "PCGExSubModulesConfig.ini",
    "plugins_deps": plugin_root / "Config" / "PluginsDeps.ini",
}


# =============================================================================
# Fuzzy Matching
# =============================================================================


def levenshtein_distance(a: str, b: str) -> int:
    if len(a) < len(b):
        a, b = b, a

    if len(b) == 0:
        return len(a)

    prev_row = list(range(len(b) + 1))
    for i, ca in enumerate(a):
        curr_row = [i + 1]
        for j, cb in enumerate(b):
            insertions = prev_row[j + 1] + 1
            deletions = curr_row[j] + 1
            substitutions = prev_row[j] + (ca != cb)
            curr_row.append(min(insertions, deletions, substitutions))
        prev_row = curr_row

    return prev_row[-1]


def find_closest_match(name: str, candidates: list[str], max_distance: int = 3) -> str | None:
    best = None
    best_distance = float("inf")

    for candidate in candidates:
        distance = levenshtein_distance(name.lower(), candidate.lower())
        if distance < best_distance and distance <= max_distance:
            best_distance = distance
            best = candidate

    return best


# =============================================================================
# INI Parsing
# =============================================================================


def resolve_submodules_config_path() -> tuple[Path, bool] | None:
    """Returns (path, is_project_level) or None if not found."""
    # Check project-level config first
    if PATHS["project_submodules_config"].exists():
        return (PATHS["project_submodules_config"], True)
    # Fall back to plugin config
    if PATHS["plugin_submodules_config"].exists():
        return (PATHS["plugin_submodules_config"], False)
    return None


def parse_submodules_config(file_path: Path) -> list[str]:
    modules = []
    content = file_path.read_text(encoding="utf-8")

    for line in content.splitlines():
        trimmed = line.strip()
        if not trimmed or trimmed.startswith("#") or trimmed.startswith(";"):
            continue

        # Support both "ModuleName=1" and plain "ModuleName" formats
        parts = trimmed.split("=")
        module_name = parts[0].strip()

        if len(parts) == 1 or parts[1].strip() == "1":
            if module_name.startswith(MODULE_PREFIX):
                modules.append(module_name)

    return modules


def parse_plugins_deps(file_path: Path) -> dict[str, list[str]]:
    deps: dict[str, list[str]] = {}

    if not file_path.exists():
        print(f"PluginsDeps.ini not found at: {file_path} - skipping plugin dependencies")
        return deps

    content = file_path.read_text(encoding="utf-8")
    current_module = None

    for line in content.splitlines():
        trimmed = line.strip()
        if not trimmed or trimmed.startswith("#") or trimmed.startswith(";"):
            continue

        # Section header: [ModuleName]
        section_match = re.match(r"^\[(.+)\]$", trimmed)
        if section_match:
            current_module = section_match.group(1)
            if current_module not in deps:
                deps[current_module] = []
            continue

        # Plugin name under current section
        if current_module and trimmed:
            deps[current_module].append(trimmed)

    return deps


# =============================================================================
# Module Discovery
# =============================================================================


def get_available_modules() -> list[str]:
    modules_dir = PATHS["modules_dir"]
    if not modules_dir.exists():
        return []

    return [
        name
        for name in os.listdir(modules_dir)
        if (modules_dir / name).is_dir() and name.startswith(MODULE_PREFIX)
    ]


def module_exists(module_name: str) -> bool:
    module_path = PATHS["modules_dir"] / module_name
    return module_path.is_dir()


def get_editor_companion(module_name: str) -> str | None:
    if module_name.endswith(EDITOR_SUFFIX):
        return None
    editor_name = module_name + EDITOR_SUFFIX
    return editor_name if module_exists(editor_name) else None


def scan_build_cs_dependencies(module_name: str) -> list[str]:
    build_file = PATHS["modules_dir"] / module_name / f"{module_name}.Build.cs"
    if not build_file.exists():
        return []

    content = build_file.read_text(encoding="utf-8")
    deps = []

    # Match: PublicDependencyModuleNames.AddRange(new[] { ... }) or similar
    block_pattern = re.compile(
        r"(?:Public|Private)DependencyModuleNames\s*\.\s*AddRange\s*\(\s*new\s*(?:string)?\s*\[\s*\]\s*\{([^}]*)\}",
        re.DOTALL,
    )
    name_pattern = re.compile(r'"(PCGEx\w+)"')

    for block_match in block_pattern.finditer(content):
        array_content = block_match.group(1)
        for name_match in name_pattern.finditer(array_content):
            dep = name_match.group(1)
            if dep != module_name and dep not in deps:
                deps.append(dep)

    return deps


# =============================================================================
# Module Resolution
# =============================================================================


def validate_requested_modules(
    requested_modules: list[str], available_modules: list[str]
) -> tuple[list[str], list[dict]]:
    valid = []
    invalid = []

    for module_name in requested_modules:
        if module_exists(module_name):
            valid.append(module_name)
        else:
            suggestion = find_closest_match(module_name, available_modules)
            invalid.append({"name": module_name, "suggestion": suggestion})

    return valid, invalid


def resolve_all_modules(requested_modules: list[str]) -> set[str]:
    resolved: set[str] = set()
    queue = list(requested_modules)

    while queue:
        module_name = queue.pop(0)

        if module_name in resolved:
            continue
        if not module_exists(module_name):
            continue  # Already warned during validation

        resolved.add(module_name)

        # Add editor companion if exists
        editor = get_editor_companion(module_name)
        if editor and editor not in resolved:
            queue.append(editor)

        # Add PCGEx dependencies
        deps = scan_build_cs_dependencies(module_name)
        for dep in deps:
            if dep not in resolved:
                queue.append(dep)

    return resolved


# =============================================================================
# Uplugin Generation
# =============================================================================


def load_existing_uplugin() -> str:
    uplugin_path = PATHS["uplugin"]
    if not uplugin_path.exists():
        print(f".uplugin not found at: {uplugin_path}", file=sys.stderr)
        sys.exit(1)

    return uplugin_path.read_text(encoding="utf-8")


def build_module_entry(name: str) -> dict:
    is_editor = name.endswith(EDITOR_SUFFIX)
    return {
        "Name": name,
        "Type": "Editor" if is_editor else "Runtime",
        "LoadingPhase": "Default",
        "PlatformAllowList": list(PLATFORMS["editor"] if is_editor else PLATFORMS["runtime"]),
    }


def build_plugin_entry(name: str) -> dict:
    return {"Name": name, "Enabled": True}


def resolve_required_plugins(modules: set[str], plugins_deps: dict[str, list[str]]) -> set[str]:
    plugins = {"PCG"}  # PCG is always required

    for module_name in modules:
        required = plugins_deps.get(module_name)
        if required:
            plugins.update(required)

    return plugins


def module_sort_key(name: str) -> tuple[int, int, str]:
    is_umbrella = name == PLUGIN_NAME or name == PLUGIN_NAME + EDITOR_SUFFIX
    if is_umbrella:
        # Main umbrella first (0), then editor umbrella (1)
        return (0, 0 if name == PLUGIN_NAME else 1, name)
    return (1, 0, name)


def generate_uplugin(existing_uplugin: dict, modules: set[str], plugins: set[str]) -> dict:
    # Always include umbrella modules
    all_modules = set(modules)
    all_modules.add(PLUGIN_NAME)
    all_modules.add(PLUGIN_NAME + EDITOR_SUFFIX)

    # Build new uplugin preserving all existing metadata
    new_uplugin = dict(existing_uplugin)

    new_uplugin["Modules"] = [
        build_module_entry(name) for name in sorted(all_modules, key=module_sort_key)
    ]

    def plugin_sort_key(name: str) -> tuple[int, str]:
        return (0, name) if name == "PCG" else (1, name)

    new_uplugin["Plugins"] = [
        build_plugin_entry(name) for name in sorted(plugins, key=plugin_sort_key)
    ]

    return new_uplugin


# =============================================================================
# Build Artifact Cleanup
# =============================================================================


def delete_folder(folder_path: Path) -> bool:
    if not folder_path.exists():
        return False

    shutil.rmtree(folder_path)
    return True


def clean_build_artifacts():
    print("\n[CLEANUP] .uplugin changed - invalidating build artifacts...")

    cleaned = False

    if delete_folder(PATHS["binaries"]):
        print(f"  Deleted: {PATHS['binaries']}")
        cleaned = True

    if delete_folder(PATHS["intermediate"]):
        print(f"  Deleted: {PATHS['intermediate']}")
        cleaned = True

    if not cleaned:
        print("  No build artifacts to clean.")


# =============================================================================
# Main
# =============================================================================


def main():
    print(f"Generating {PLUGIN_NAME}.uplugin...")
    print(f"Plugin root: {plugin_root}")
    print(f"Project root: {project_root}")

    # Resolve config path (project-level or plugin-level)
    config_info = resolve_submodules_config_path()
    if not config_info:
        print("PCGExSubModulesConfig.ini not found.", file=sys.stderr)
        print("Searched:", file=sys.stderr)
        print(f"  - {PATHS['project_submodules_config']}", file=sys.stderr)
        print(f"  - {PATHS['plugin_submodules_config']}", file=sys.stderr)
        sys.exit(1)

    config_path, is_project_level = config_info
    config_source = "project" if is_project_level else "plugin"
    print(f"Using {config_source}-level config: {config_path}")

    # Get available modules for validation and suggestions
    available_modules = get_available_modules()
    print(f"Available modules on disk: {len(available_modules)}")

    # Parse configs
    requested_modules = parse_submodules_config(config_path)
    print(f"Requested modules: {len(requested_modules)}")

    # Validate requested modules
    valid, invalid = validate_requested_modules(requested_modules, available_modules)

    if invalid:
        print("\n[WARNING] Invalid module names in PCGExSubModulesConfig.ini:", file=sys.stderr)
        for item in invalid:
            name = item["name"]
            suggestion = item["suggestion"]
            if suggestion:
                print(f"  - '{name}' not found. Did you mean '{suggestion}'?", file=sys.stderr)
            else:
                print(f"  - '{name}' not found.", file=sys.stderr)
        print(file=sys.stderr)

    plugins_deps = parse_plugins_deps(PATHS["plugins_deps"])
    print(f"Plugin dependencies defined for: {len(plugins_deps)} modules")

    # Resolve all modules (with deps and editor companions)
    all_modules = resolve_all_modules(valid)
    print(f"Resolved modules (with dependencies): {len(all_modules)}")

    # Resolve required plugins
    required_plugins = resolve_required_plugins(all_modules, plugins_deps)
    print(f"Required plugins: {', '.join(sorted(required_plugins))}")

    # Load existing uplugin content (as string for comparison)
    existing_content = load_existing_uplugin()
    existing_uplugin = json.loads(existing_content)

    # Generate new uplugin
    new_uplugin = generate_uplugin(existing_uplugin, all_modules, required_plugins)
    new_content = json.dumps(new_uplugin, indent=2, ensure_ascii=False)

    # Check if content changed
    has_changed = existing_content != new_content

    if has_changed:
        # Clean build artifacts before writing new uplugin
        # clean_build_artifacts()

        # Write new uplugin
        PATHS["uplugin"].write_text(new_content, encoding="utf-8")
        print(f"\nGenerated {PATHS['uplugin']}")
    else:
        print("\n.uplugin unchanged - skipping write.")

    print(f"  Modules: {len(new_uplugin['Modules'])}")
    print(f"  Plugins: {len(new_uplugin['Plugins'])}")

    # Exit with warning code if there were invalid modules
    if invalid:
        sys.exit(0)  # Still succeeds, but you could use sys.exit(1) to fail the build


if __name__ == "__main__":
    main()