// ========= Copyright 2025-2026 @ Eigent.ai All Rights Reserved. =========
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
// ========= Copyright 2025-2026 @ Eigent.ai All Rights Reserved. =========

import { vi } from 'vitest';

/**
 * Environment state management for testing installation flows
 * This module provides utilities to simulate different system states
 */

export interface MockEnvironmentState {
  filesystem: {
    venvExists: boolean;
    versionFileExists: boolean;
    versionFileContent: string;
    installingLockExists: boolean;
    installedLockExists: boolean;
    backendPathExists: boolean;
    pyprojectExists: boolean;
    // New fields for process.ts functions
    eigentDirExists: boolean;
    eigentBinDirExists: boolean;
    eigentCacheDirExists: boolean;
    eigentVenvsDirExists: boolean;
    eigentRuntimeDirExists: boolean;
    resourcesDirExists: boolean;
    binariesExist: { [name: string]: boolean };
    oldVenvsExist: string[]; // List of old venv directories that exist
  };
  processes: {
    uvAvailable: boolean;
    bunAvailable: boolean;
    uvicornRunning: boolean;
    uvSyncInProgress: boolean;
    installationInProgress: boolean;
  };
  app: {
    currentVersion: string;
    userData: string;
    appPath: string;
    isPackaged: boolean;
    resourcesPath: string;
  };
  system: {
    platform: 'win32' | 'darwin' | 'linux';
    homedir: string;
  };
  network: {
    canConnectToMirror: boolean;
    canConnectToDefault: boolean;
  };
}

/**
 * Mock implementations for Node.js fs module
 */
export function createFileSystemMock() {
  const mockState: MockEnvironmentState = {
    filesystem: {
      venvExists: true,
      versionFileExists: true,
      versionFileContent: '1.0.0',
      installingLockExists: false,
      installedLockExists: true,
      backendPathExists: true,
      pyprojectExists: true,
      eigentDirExists: true,
      eigentBinDirExists: true,
      eigentCacheDirExists: true,
      eigentVenvsDirExists: true,
      eigentRuntimeDirExists: true,
      resourcesDirExists: true,
      binariesExist: { uv: true, bun: true },
      oldVenvsExist: [],
    },
    processes: {
      uvAvailable: true,
      bunAvailable: true,
      uvicornRunning: false,
      uvSyncInProgress: false,
      installationInProgress: false,
    },
    app: {
      currentVersion: '1.0.0',
      userData: '/mock/user/data',
      appPath: '/mock/app/path',
      isPackaged: false,
      resourcesPath: '/mock/resources/path',
    },
    system: {
      platform: 'win32',
      homedir: '/mock/home',
    },
    network: {
      canConnectToMirror: true,
      canConnectToDefault: true,
    },
  };

  const fsMock = {
    existsSync: vi.fn().mockImplementation((path: string) => {
      if (!path || typeof path !== 'string') return false;
      if (path.includes('version.txt'))
        return mockState.filesystem.versionFileExists;
      if (path.includes('uv_installing.lock'))
        return mockState.filesystem.installingLockExists;
      if (path.includes('uv_installed.lock'))
        return mockState.filesystem.installedLockExists;
      if (path.includes('.venv')) return mockState.filesystem.venvExists;
      if (path.includes('backend'))
        return mockState.filesystem.backendPathExists;
      if (path.includes('pyproject.toml'))
        return mockState.filesystem.pyprojectExists;
      if (path.includes('.eigent/bin') || path.includes('.eigent\\bin'))
        return mockState.filesystem.eigentBinDirExists;
      if (path.includes('.eigent/cache') || path.includes('.eigent\\cache'))
        return mockState.filesystem.eigentCacheDirExists;
      if (path.includes('.eigent/venvs') || path.includes('.eigent\\venvs'))
        return mockState.filesystem.eigentVenvsDirExists;
      if (path.includes('.eigent/runtime') || path.includes('.eigent\\runtime'))
        return mockState.filesystem.eigentRuntimeDirExists;
      if (
        path.includes('.eigent') &&
        !path.includes('bin') &&
        !path.includes('cache') &&
        !path.includes('venvs') &&
        !path.includes('runtime')
      ) {
        return mockState.filesystem.eigentDirExists;
      }
      if (path.includes('resources'))
        return mockState.filesystem.resourcesDirExists;
      // Check for specific binaries
      for (const [name, exists] of Object.entries(
        mockState.filesystem.binariesExist
      )) {
        if (path.includes(name + '.exe') || path.endsWith(name)) {
          return exists;
        }
      }
      // Check for old venv directories
      for (const oldVenv of mockState.filesystem.oldVenvsExist) {
        if (path.includes(oldVenv)) return true;
      }
      return true;
    }),

    readFileSync: vi
      .fn()
      .mockImplementation((path: string, _encoding?: string) => {
        if (!path || typeof path !== 'string') return '';
        if (path.includes('version.txt')) {
          return mockState.filesystem.versionFileContent;
        }
        if (path.includes('pyproject.toml')) {
          return `
[project]
name = "backend"
version = "1.0.0"
dependencies = ["fastapi", "uvicorn"]
        `;
        }
        return '';
      }),

    writeFileSync: vi
      .fn()
      .mockImplementation((path: string, content: string) => {
        if (!path || typeof path !== 'string') return;
        if (path.includes('version.txt')) {
          mockState.filesystem.versionFileContent = content;
          mockState.filesystem.versionFileExists = true;
        } else if (path.includes('uv_installing.lock')) {
          mockState.filesystem.installingLockExists = true;
        } else if (path.includes('uv_installed.lock')) {
          mockState.filesystem.installedLockExists = true;
        }
      }),

    unlinkSync: vi.fn().mockImplementation((path: string) => {
      if (!path || typeof path !== 'string') return;
      if (path.includes('uv_installing.lock')) {
        mockState.filesystem.installingLockExists = false;
      } else if (path.includes('uv_installed.lock')) {
        mockState.filesystem.installedLockExists = false;
      } else if (path.includes('version.txt')) {
        mockState.filesystem.versionFileExists = false;
      }
    }),

    mkdirSync: vi.fn().mockImplementation((path: string, _options?: any) => {
      if (!path || typeof path !== 'string') return;
      if (path.includes('backend')) {
        mockState.filesystem.backendPathExists = true;
      } else if (
        path.includes('.eigent/bin') ||
        path.includes('.eigent\\bin')
      ) {
        mockState.filesystem.eigentBinDirExists = true;
      } else if (
        path.includes('.eigent/cache') ||
        path.includes('.eigent\\cache')
      ) {
        mockState.filesystem.eigentCacheDirExists = true;
      } else if (
        path.includes('.eigent/venvs') ||
        path.includes('.eigent\\venvs')
      ) {
        mockState.filesystem.eigentVenvsDirExists = true;
      } else if (
        path.includes('.eigent/runtime') ||
        path.includes('.eigent\\runtime')
      ) {
        mockState.filesystem.eigentRuntimeDirExists = true;
      } else if (path.includes('.eigent')) {
        mockState.filesystem.eigentDirExists = true;
      }
    }),

    rmSync: vi.fn().mockImplementation((path: string, _options?: any) => {
      if (!path || typeof path !== 'string') return;
      // Handle cleanup of old venvs
      for (let i = 0; i < mockState.filesystem.oldVenvsExist.length; i++) {
        if (path.includes(mockState.filesystem.oldVenvsExist[i])) {
          mockState.filesystem.oldVenvsExist.splice(i, 1);
          break;
        }
      }
    }),

    readdirSync: vi.fn().mockImplementation((path: string, _options?: any) => {
      if (!path || typeof path !== 'string') return [];
      if (path.includes('.eigent/venvs')) {
        // Return old venv directories for cleanup testing
        return mockState.filesystem.oldVenvsExist.map((venv) => ({
          name: venv,
          isDirectory: () => true,
        }));
      }
      return [];
    }),

    // State control methods
    mockState,

    reset: () => {
      Object.assign(mockState, {
        filesystem: {
          venvExists: true,
          versionFileExists: true,
          versionFileContent: '1.0.0',
          installingLockExists: false,
          installedLockExists: true,
          backendPathExists: true,
          pyprojectExists: true,
          eigentDirExists: true,
          eigentBinDirExists: true,
          eigentCacheDirExists: true,
          eigentVenvsDirExists: true,
          eigentRuntimeDirExists: true,
          resourcesDirExists: true,
          binariesExist: { uv: true, bun: true },
          oldVenvsExist: [],
        },
        processes: {
          uvAvailable: true,
          bunAvailable: true,
          uvicornRunning: false,
          uvSyncInProgress: false,
          installationInProgress: false,
        },
        app: {
          currentVersion: '1.0.0',
          userData: '/mock/user/data',
          appPath: '/mock/app/path',
          isPackaged: false,
          resourcesPath: '/mock/resources/path',
        },
        system: {
          platform: 'win32',
          homedir: '/mock/home',
        },
        network: {
          canConnectToMirror: true,
          canConnectToDefault: true,
        },
      });
    },
  };

  return fsMock;
}

/**
 * Mock implementations for child_process spawn
 */
export function createProcessMock() {
  const processMock = {
    spawn: vi.fn(),
    mockState: {} as MockEnvironmentState,

    setupSpawnMock: (mockState: MockEnvironmentState) => {
      processMock.mockState = mockState;

      processMock.spawn.mockImplementation(
        (command: string, args: string[], _options: any) => {
          // Mock process events
          const mockProcess = {
            stdout: {
              on: vi
                .fn()
                .mockImplementation(
                  (event: string, callback: (data: Buffer) => void) => {
                    if (event === 'data') {
                      // Simulate different process outputs based on command
                      setTimeout(() => {
                        if (command.includes('uv') && args.includes('sync')) {
                          mockState.processes.uvSyncInProgress = true;
                          callback(
                            Buffer.from('Resolved 10 packages in 1.2s\n')
                          );
                          setTimeout(() => {
                            callback(Buffer.from('Installing packages...\n'));
                            setTimeout(() => {
                              callback(Buffer.from('Installation complete\n'));
                              mockState.processes.uvSyncInProgress = false;
                            }, 100);
                          }, 50);
                        } else if (command.includes('uvicorn')) {
                          mockState.processes.uvicornRunning = true;
                          callback(
                            Buffer.from(
                              'Uvicorn running on http://127.0.0.1:8000\n'
                            )
                          );
                        }
                      }, 10);
                    }
                  }
                ),
            },
            stderr: {
              on: vi
                .fn()
                .mockImplementation(
                  (event: string, callback: (data: Buffer) => void) => {
                    if (event === 'data') {
                      // Simulate error scenarios
                      if (
                        !mockState.processes.uvAvailable &&
                        command.includes('uv')
                      ) {
                        setTimeout(() => {
                          callback(Buffer.from('uv: command not found\n'));
                        }, 10);
                      }
                    }
                  }
                ),
            },
            on: vi
              .fn()
              .mockImplementation(
                (event: string, callback: (code: number) => void) => {
                  if (event === 'close') {
                    setTimeout(() => {
                      if (command.includes('uv') && args.includes('sync')) {
                        const exitCode =
                          mockState.processes.uvAvailable &&
                          mockState.network.canConnectToDefault
                            ? 0
                            : 1;
                        callback(exitCode);
                      } else {
                        callback(0);
                      }
                    }, 150);
                  }
                }
              ),
            kill: vi.fn(),
          };

          return mockProcess;
        }
      );
    },

    reset: () => {
      processMock.spawn.mockReset();
    },
  };

  return processMock;
}

/**
 * Mock for Electron app module
 */
export function createElectronAppMock() {
  const appMock = {
    getVersion: vi.fn(),
    getPath: vi.fn(),
    getAppPath: vi.fn(),
    isPackaged: false,
    mockState: {} as MockEnvironmentState,

    setup: (mockState: MockEnvironmentState) => {
      appMock.mockState = mockState;
      appMock.getVersion.mockReturnValue(mockState.app.currentVersion);
      appMock.getAppPath.mockReturnValue(mockState.app.appPath);
      appMock.isPackaged = mockState.app.isPackaged;
      appMock.getPath.mockImplementation((name: string) => {
        if (name === 'userData') return mockState.app.userData;
        return '/mock/path';
      });

      // Mock process.resourcesPath for packaged apps
      if (mockState.app.isPackaged) {
        Object.defineProperty(process, 'resourcesPath', {
          value: mockState.app.resourcesPath,
          configurable: true,
        });
      }
    },

    reset: () => {
      appMock.getVersion.mockReset();
      appMock.getPath.mockReset();
      appMock.getAppPath.mockReset();
    },
  };

  return appMock;
}

/**
 * Mock for OS module
 */
export function createOsMock() {
  const osMock = {
    homedir: vi.fn().mockReturnValue('/mock/home'),
    mockState: {} as MockEnvironmentState,

    setup: (mockState: MockEnvironmentState) => {
      osMock.mockState = mockState;
      osMock.homedir.mockReturnValue(mockState.system.homedir || '/mock/home');
    },

    reset: () => {
      osMock.homedir.mockReset();
      osMock.homedir.mockReturnValue('/mock/home');
    },
  };

  return osMock;
}

/**
 * Mock for path module
 */
export function createPathMock() {
  return {
    join: vi.fn((...args) => {
      const validArgs = args.filter(
        (arg) => arg != null && arg !== undefined && arg !== ''
      );
      return validArgs.length > 0
        ? validArgs.join(process.platform === 'win32' ? '\\' : '/')
        : '';
    }),
    resolve: vi.fn((...args) => {
      const validArgs = args.filter(
        (arg) => arg != null && arg !== undefined && arg !== ''
      );
      return validArgs.length > 0
        ? validArgs.join(process.platform === 'win32' ? '\\' : '/')
        : '';
    }),
    dirname: vi.fn((path: string) => {
      if (!path || typeof path !== 'string') return '';
      const parts = path.split(process.platform === 'win32' ? '\\' : '/');
      return parts.slice(0, -1).join(process.platform === 'win32' ? '\\' : '/');
    }),
  };
}

/**
 * Mock for process utilities from electron/main/utils/process.ts
 */
export function createProcessUtilsMock() {
  const utilsMock = {
    getResourcePath: vi.fn(),
    getBackendPath: vi.fn(),
    runInstallScript: vi.fn(),
    getBinaryName: vi.fn(),
    getBinaryPath: vi.fn(),
    getCachePath: vi.fn(),
    getVenvPath: vi.fn(),
    getVenvsBaseDir: vi.fn(),
    cleanupOldVenvs: vi.fn(),
    isBinaryExists: vi.fn(),
    getUvEnv: vi.fn(),
    mockState: {} as MockEnvironmentState,

    setup: (mockState: MockEnvironmentState) => {
      utilsMock.mockState = mockState;

      utilsMock.getUvEnv.mockReturnValue({
        UV_PYTHON_INSTALL_DIR: `${mockState.system.homedir}/.eigent/cache/uv_python`,
        UV_TOOL_DIR: `${mockState.system.homedir}/.eigent/cache/uv_tool`,
        UV_PROJECT_ENVIRONMENT: `${mockState.system.homedir}/.eigent/venvs/backend-mock`,
        UV_HTTP_TIMEOUT: '300',
      });

      utilsMock.getResourcePath.mockReturnValue(
        `${mockState.app.appPath}/resources`
      );

      utilsMock.getBackendPath.mockReturnValue(
        mockState.app.isPackaged
          ? `${mockState.app.resourcesPath}/backend`
          : `${mockState.app.appPath}/backend`
      );

      utilsMock.runInstallScript.mockImplementation(
        async (scriptPath: string) => {
          // Simulate successful script execution and update binary state
          if (scriptPath.includes('install-uv')) {
            mockState.filesystem.binariesExist['uv'] = true;
            mockState.processes.uvAvailable = true;
          } else if (scriptPath.includes('install-bun')) {
            mockState.filesystem.binariesExist['bun'] = true;
            mockState.processes.bunAvailable = true;
          }
          return true;
        }
      );

      utilsMock.getBinaryName.mockImplementation(async (name: string) => {
        return mockState.system.platform === 'win32' ? `${name}.exe` : name;
      });

      utilsMock.getBinaryPath.mockImplementation(async (name?: string) => {
        const binDir = `${mockState.system.homedir}/.eigent/bin`;
        if (!name) return binDir;
        const binaryName =
          mockState.system.platform === 'win32' ? `${name}.exe` : name;
        return `${binDir}/${binaryName}`;
      });

      utilsMock.getCachePath.mockImplementation((folder: string) => {
        return `${mockState.system.homedir}/.eigent/cache/${folder}`;
      });

      utilsMock.getVenvPath.mockImplementation((version: string) => {
        return `${mockState.system.homedir}/.eigent/venvs/backend-${version}`;
      });

      utilsMock.getVenvsBaseDir.mockReturnValue(
        `${mockState.system.homedir}/.eigent/venvs`
      );

      utilsMock.cleanupOldVenvs.mockImplementation(
        async (currentVersion: string) => {
          // Simulate cleanup by removing old venvs from mock state
          mockState.filesystem.oldVenvsExist =
            mockState.filesystem.oldVenvsExist.filter((venv) =>
              venv.includes(`backend-${currentVersion}`)
            );
        }
      );

      utilsMock.isBinaryExists.mockImplementation(async (name: string) => {
        return mockState.filesystem.binariesExist[name] || false;
      });
    },

    reset: () => {
      Object.values(utilsMock).forEach((fn) => {
        if (typeof fn === 'function' && 'mockReset' in fn) {
          fn.mockReset();
        }
      });
    },
  };

  return utilsMock;
}

/**
 * Mock for electron-log
 */
export function createLogMock() {
  return {
    info: vi.fn(),
    error: vi.fn(),
    warn: vi.fn(),
    debug: vi.fn(),
  };
}

/**
 * Complete environment setup for testing
 * Note: vi.mock calls should be done at the top level of test files, not here
 */
export function setupMockEnvironment() {
  const fsMock = createFileSystemMock();
  const processMock = createProcessMock();
  const appMock = createElectronAppMock();
  const osMock = createOsMock();
  const pathMock = createPathMock();
  const processUtilsMock = createProcessUtilsMock();
  const logMock = createLogMock();

  // Set up the shared state
  processMock.setupSpawnMock(fsMock.mockState);
  appMock.setup(fsMock.mockState);
  osMock.setup(fsMock.mockState);
  processUtilsMock.setup(fsMock.mockState);

  return {
    fsMock,
    processMock,
    appMock,
    osMock,
    pathMock,
    processUtilsMock,
    logMock,
    mockState: fsMock.mockState,

    // Utility functions for test scenarios
    scenarios: {
      freshInstall: () => {
        fsMock.mockState.filesystem.venvExists = false;
        fsMock.mockState.filesystem.versionFileExists = false;
        fsMock.mockState.filesystem.installedLockExists = false;
        fsMock.mockState.filesystem.binariesExist = { uv: false, bun: false };
        fsMock.mockState.processes.uvAvailable = false;
        fsMock.mockState.processes.bunAvailable = false;
      },

      versionUpdate: (oldVersion: string, newVersion: string) => {
        fsMock.mockState.filesystem.versionFileContent = oldVersion;
        fsMock.mockState.app.currentVersion = newVersion;
        appMock.getVersion.mockReturnValue(newVersion);
      },

      venvRemoved: () => {
        fsMock.mockState.filesystem.venvExists = false;
        fsMock.mockState.filesystem.installedLockExists = false;
      },

      networkIssues: () => {
        fsMock.mockState.network.canConnectToDefault = false;
        fsMock.mockState.network.canConnectToMirror = true;
      },

      completeFailure: () => {
        fsMock.mockState.network.canConnectToDefault = false;
        fsMock.mockState.network.canConnectToMirror = false;
        fsMock.mockState.processes.uvAvailable = false;
        fsMock.mockState.filesystem.binariesExist = { uv: false, bun: false };

        // Note: installCommandTool is defined in the install-deps module,
        // not in process utils, so it should be mocked in the test itself
      },

      uvicornStartupInstall: () => {
        fsMock.mockState.processes.uvicornRunning = false;
        fsMock.mockState.filesystem.installedLockExists = false;
        // Uvicorn will detect missing deps and start installation
      },

      installationInProgress: () => {
        fsMock.mockState.filesystem.installingLockExists = true;
        fsMock.mockState.processes.installationInProgress = true;
      },

      // New scenarios for process.ts testing
      packagedApp: () => {
        fsMock.mockState.app.isPackaged = true;
        appMock.isPackaged = true;
      },

      multipleOldVenvs: (currentVersion: string) => {
        fsMock.mockState.filesystem.oldVenvsExist = [
          'backend-0.9.0',
          'backend-0.9.5',
          'backend-1.0.1-beta',
          `backend-${currentVersion}`, // This should not be cleaned up
        ];
      },

      macOSEnvironment: () => {
        fsMock.mockState.system.platform = 'darwin';
        Object.defineProperty(process, 'platform', {
          value: 'darwin',
          configurable: true,
        });
      },

      linuxEnvironment: () => {
        fsMock.mockState.system.platform = 'linux';
        Object.defineProperty(process, 'platform', {
          value: 'linux',
          configurable: true,
        });
      },

      missingEigentDirectories: () => {
        fsMock.mockState.filesystem.eigentDirExists = false;
        fsMock.mockState.filesystem.eigentBinDirExists = false;
        fsMock.mockState.filesystem.eigentCacheDirExists = false;
        fsMock.mockState.filesystem.eigentVenvsDirExists = false;
        fsMock.mockState.filesystem.eigentRuntimeDirExists = false;
      },
    },

    reset: () => {
      fsMock.reset();
      processMock.reset();
      appMock.reset();
      osMock.reset();
      processUtilsMock.reset();

      // Reset process.platform to original
      Object.defineProperty(process, 'platform', {
        value: 'win32',
        configurable: true,
      });
    },
  };
}

/**
 * Factory functions for creating mocks that can be used in vi.mock calls
 * These should be called at the top level of test files
 */
export function createMockFactories() {
  return {
    fs: () => createFileSystemMock(),
    childProcess: () => createProcessMock(),
    os: () => ({ default: createOsMock() }),
    path: () => ({ default: createPathMock() }),
    electron: () => ({
      app: createElectronAppMock(),
      BrowserWindow: vi.fn(),
    }),
    electronLog: () => ({ default: createLogMock() }),
    processUtils: () => createProcessUtilsMock(),
  };
}

/**
 * Test utility to wait for async state changes
 */
export function waitForStateChange<T>(
  stateGetter: () => T,
  expectedValue: T,
  timeout: number = 1000
): Promise<void> {
  return new Promise((resolve, reject) => {
    const startTime = Date.now();

    const check = () => {
      if (stateGetter() === expectedValue) {
        resolve();
      } else if (Date.now() - startTime > timeout) {
        reject(
          new Error(
            `Timeout waiting for state change. Expected: ${expectedValue}, got: ${stateGetter()}`
          )
        );
      } else {
        setTimeout(check, 10);
      }
    };

    check();
  });
}