import { createProjectIdFromPath } from '../projects/project-id.js';
import fs from 'fs';
import os from 'os';
import path from 'path';

export const registerOpenCodeRoutes = (app, dependencies) => {
  const {
    crypto,
    clientReloadDelayMs,
    getOpenCodeResolutionSnapshot,
    formatSettingsResponse,
    readSettingsFromDisk,
    readSettingsFromDiskMigrated,
    persistSettings,
    sanitizeProjects,
    validateDirectoryPath,
    resolveProjectDirectory,
    getProviderSources,
    removeProviderConfig,
    refreshOpenCodeAfterConfigChange,
    buildOpenCodeUrl,
    getOpenCodeAuthHeaders,
  } = dependencies;

  let authLibrary = null;
  const pendingMcpAuthContextByState = new Map();
  const PENDING_MCP_AUTH_TTL_MS = 30 * 60 * 1000;
  const getAuthLibrary = async () => {
    if (!authLibrary) {
      authLibrary = await import('./auth.js');
    }
    return authLibrary;
  };

  const normalizePendingString = (value) => {
    if (typeof value !== 'string') {
      return null;
    }

    const trimmed = value.trim();
    return trimmed || null;
  };

  const parseVersionForComparison = (value) => {
    const normalized = String(value || '').replace(/^v/, '').split('+')[0];
    const prereleaseIndex = normalized.indexOf('-');
    const core = prereleaseIndex >= 0 ? normalized.slice(0, prereleaseIndex) : normalized;
    const parts = core.split('.').map((part) => {
      const parsed = Number.parseInt(part || '0', 10);
      return Number.isFinite(parsed) ? parsed : 0;
    });
    return { parts, prerelease: prereleaseIndex >= 0 };
  };

  const compareVersions = (left, right) => {
    const a = parseVersionForComparison(left);
    const b = parseVersionForComparison(right);
    const length = Math.max(a.parts.length, b.parts.length);
    for (let index = 0; index < length; index += 1) {
      const diff = (a.parts[index] || 0) - (b.parts[index] || 0);
      if (diff !== 0) return diff;
    }
    if (a.prerelease !== b.prerelease) return a.prerelease ? -1 : 1;
    return 0;
  };

  const fetchLatestOpenCodeVersionFromGithub = async () => {
    const response = await fetch('https://api.github.com/repos/anomalyco/opencode/releases/latest', {
      headers: { Accept: 'application/json' },
      signal: AbortSignal.timeout(10_000),
    });
    if (!response.ok) {
      throw new Error(`OpenCode releases responded with ${response.status}`);
    }
    const payload = await response.json();
    const tag = typeof payload?.tag_name === 'string' ? payload.tag_name.trim() : '';
    return tag.replace(/^v/, '');
  };

  const fetchLatestOpenCodeVersionFromNpm = async () => {
    const response = await fetch('https://registry.npmjs.org/opencode-ai/latest', {
      headers: { Accept: 'application/json' },
      signal: AbortSignal.timeout(10_000),
    });
    if (!response.ok) {
      throw new Error(`OpenCode npm registry responded with ${response.status}`);
    }
    const payload = await response.json();
    return typeof payload?.version === 'string' ? payload.version.trim().replace(/^v/, '') : '';
  };

  const fetchLatestOpenCodeVersion = async () => {
    const results = await Promise.allSettled([
      fetchLatestOpenCodeVersionFromNpm(),
      fetchLatestOpenCodeVersionFromGithub(),
    ]);
    const versions = results
      .filter((result) => result.status === 'fulfilled' && result.value)
      .map((result) => result.value);
    if (versions.length === 0) {
      const failure = results.find((result) => result.status === 'rejected');
      throw failure?.reason instanceof Error ? failure.reason : new Error('Failed to resolve latest OpenCode version');
    }
    return versions.sort((left, right) => compareVersions(right, left))[0];
  };

  const pruneExpiredPendingMcpAuthContexts = () => {
    const now = Date.now();
    for (const [state, entry] of pendingMcpAuthContextByState.entries()) {
      if (!entry || typeof entry.expiresAt !== 'number' || entry.expiresAt <= now) {
        pendingMcpAuthContextByState.delete(state);
      }
    }
  };

  app.get('/api/config/settings', async (_req, res) => {
    try {
      const settings = await readSettingsFromDiskMigrated();
      res.json(formatSettingsResponse(settings));
    } catch (error) {
      console.error('Failed to read settings:', error);
      res.status(500).json({ error: 'Failed to read settings' });
    }
  });

  app.get('/api/config/opencode-resolution', async (_req, res) => {
    try {
      const settings = await readSettingsFromDiskMigrated();
      const resolution = await getOpenCodeResolutionSnapshot(settings);
      res.json(resolution);
    } catch (error) {
      console.error('Failed to resolve OpenCode binary:', error);
      res.status(500).json({ error: 'Failed to resolve OpenCode binary' });
    }
  });

  app.post('/api/opencode/upgrade', async (req, res) => {
    try {
      const target = typeof req.body?.target === 'string' && req.body.target.trim().length > 0
        ? req.body.target.trim()
        : undefined;
      const response = await fetch(buildOpenCodeUrl('/global/upgrade', ''), {
        method: 'POST',
        headers: {
          'Content-Type': 'application/json',
          Accept: 'application/json',
          ...getOpenCodeAuthHeaders(),
        },
        body: JSON.stringify(target ? { target } : {}),
      });
      const payload = await response.json().catch(() => null);
      if (!response.ok) {
        return res.status(response.status).json({
          success: false,
          error: payload?.error || response.statusText || 'Failed to upgrade OpenCode',
        });
      }

      try {
        await refreshOpenCodeAfterConfigChange('OpenCode upgrade');
      } catch (restartError) {
        return res.status(500).json({
          success: false,
          upgraded: true,
          error: restartError instanceof Error
            ? `OpenCode upgraded, but restart failed: ${restartError.message}`
            : 'OpenCode upgraded, but restart failed',
        });
      }

      return res.json({ ...(payload ?? { success: true }), restarted: true });
    } catch (error) {
      console.error('Failed to upgrade OpenCode:', error);
      return res.status(500).json({
        success: false,
        error: error instanceof Error ? error.message : 'Failed to upgrade OpenCode',
      });
    }
  });

  app.get('/api/opencode/upgrade-status', async (_req, res) => {
    try {
      const [healthResponse, latestVersion] = await Promise.all([
        fetch(buildOpenCodeUrl('/global/health', ''), {
          method: 'GET',
          headers: { Accept: 'application/json', ...getOpenCodeAuthHeaders() },
        }),
        fetchLatestOpenCodeVersion(),
      ]);
      const health = await healthResponse.json().catch(() => null);
      if (!healthResponse.ok) {
        return res.status(healthResponse.status).json({
          available: null,
          error: health?.error || healthResponse.statusText || 'Failed to read OpenCode version',
        });
      }
      const currentVersion = typeof health?.version === 'string' ? health.version.replace(/^v/, '') : null;
      if (!currentVersion || !latestVersion) {
        return res.json({ available: null, currentVersion, latestVersion: latestVersion || null });
      }
      const available = compareVersions(latestVersion, currentVersion) > 0;
      return res.json({
        available,
        currentVersion,
        latestVersion,
      });
    } catch (error) {
      return res.status(500).json({
        available: null,
        error: error instanceof Error ? error.message : 'Failed to check OpenCode upgrade status',
      });
    }
  });

  app.get('/api/opencode/health', async (_req, res) => {
    try {
      const healthResponse = await fetch(buildOpenCodeUrl('/global/health', ''), {
        method: 'GET',
        headers: { Accept: 'application/json', ...getOpenCodeAuthHeaders() },
      });
      const health = await healthResponse.json().catch(() => null);
      if (!healthResponse.ok) {
        return res.status(healthResponse.status).json({
          healthy: false,
          error: health?.error || healthResponse.statusText || 'OpenCode health check failed',
        });
      }
      return res.json({ healthy: health?.healthy === true });
    } catch (error) {
      return res.status(503).json({
        healthy: false,
        error: error instanceof Error ? error.message : 'OpenCode health check failed',
      });
    }
  });

  app.get('/api/opencode/version', async (_req, res) => {
    try {
      const healthResponse = await fetch(buildOpenCodeUrl('/global/health', ''), {
        method: 'GET',
        headers: { Accept: 'application/json', ...getOpenCodeAuthHeaders() },
      });
      const health = await healthResponse.json().catch(() => null);
      if (!healthResponse.ok) {
        return res.status(healthResponse.status).json({
          version: null,
          error: health?.error || healthResponse.statusText || 'Failed to read OpenCode version',
        });
      }
      const version = typeof health?.version === 'string' ? health.version.replace(/^v/, '') : null;
      return res.json({ version });
    } catch (error) {
      return res.status(500).json({
        version: null,
        error: error instanceof Error ? error.message : 'Failed to read OpenCode version',
      });
    }
  });

  app.put('/api/config/settings', async (req, res) => {
    try {
      const updated = await persistSettings(req.body ?? {});
      res.json(updated);
    } catch (error) {
      console.error('[API:PUT /api/config/settings] Failed to save settings:', error);
      console.error('[API:PUT /api/config/settings] Error stack:', error.stack);
      res.status(500).json({ error: 'Failed to save settings' });
    }
  });

  app.post('/api/mcp/auth/pending', async (req, res) => {
    try {
      pruneExpiredPendingMcpAuthContexts();

      const state = normalizePendingString(req.body?.state);
      if (!state) {
        return res.json({ success: true, context: null });
      }

      const name = normalizePendingString(req.body?.name);
      if (!name) {
        return res.status(400).json({ error: 'MCP server name is required' });
      }

      const entry = {
        name,
        directory: normalizePendingString(req.body?.directory),
        expiresAt: Date.now() + PENDING_MCP_AUTH_TTL_MS,
      };
      pendingMcpAuthContextByState.set(state, entry);

      return res.json({
        success: true,
        context: {
          name: entry.name,
          directory: entry.directory,
        },
      });
    } catch (error) {
      console.error('Failed to store pending MCP auth context:', error);
      return res.status(500).json({ error: error.message || 'Failed to store pending MCP auth context' });
    }
  });

  app.get('/api/mcp/auth/pending', async (req, res) => {
    try {
      pruneExpiredPendingMcpAuthContexts();

      const state = normalizePendingString(Array.isArray(req.query?.state) ? req.query.state[0] : req.query?.state);
      if (!state) {
        return res.json(null);
      }

      const pendingMcpAuthContext = pendingMcpAuthContextByState.get(state) ?? null;
      if (!pendingMcpAuthContext) {
        return res.status(404).json({ error: 'No pending MCP auth context' });
      }

      return res.json(pendingMcpAuthContext);
    } catch (error) {
      console.error('Failed to read pending MCP auth context:', error);
      return res.status(500).json({ error: error.message || 'Failed to read pending MCP auth context' });
    }
  });

  app.delete('/api/mcp/auth/pending', async (req, res) => {
    try {
      const state = normalizePendingString(Array.isArray(req.query?.state) ? req.query.state[0] : req.query?.state);
      if (!state) {
        return res.json({ success: true });
      }

      pendingMcpAuthContextByState.delete(state);
      return res.json({ success: true });
    } catch (error) {
      console.error('Failed to clear pending MCP auth context:', error);
      return res.status(500).json({ error: error.message || 'Failed to clear pending MCP auth context' });
    }
  });

  app.get('/api/provider/:providerId/source', async (req, res) => {
    try {
      const { providerId } = req.params;
      if (!providerId) {
        return res.status(400).json({ error: 'Provider ID is required' });
      }

      const headerDirectory = typeof req.get === 'function' ? req.get('x-opencode-directory') : null;
      const queryDirectory = Array.isArray(req.query?.directory)
        ? req.query.directory[0]
        : req.query?.directory;
      const requestedDirectory = headerDirectory || queryDirectory || null;

      let directory = null;
      const resolved = await resolveProjectDirectory(req);
      if (resolved.directory) {
        directory = resolved.directory;
      } else if (requestedDirectory) {
        return res.status(400).json({ error: resolved.error });
      }

      const sources = getProviderSources(providerId, directory);
      const { getProviderAuth } = await getAuthLibrary();
      const auth = getProviderAuth(providerId);
      sources.sources.auth.exists = Boolean(auth);

      return res.json({
        providerId,
        sources: sources.sources,
      });
    } catch (error) {
      console.error('Failed to get provider sources:', error);
      return res.status(500).json({ error: error.message || 'Failed to get provider sources' });
    }
  });

  app.delete('/api/provider/:providerId/auth', async (req, res) => {
    try {
      const { providerId } = req.params;
      if (!providerId) {
        return res.status(400).json({ error: 'Provider ID is required' });
      }

      const scope = typeof req.query?.scope === 'string' ? req.query.scope : 'auth';
      const headerDirectory = typeof req.get === 'function' ? req.get('x-opencode-directory') : null;
      const queryDirectory = Array.isArray(req.query?.directory)
        ? req.query.directory[0]
        : req.query?.directory;
      const requestedDirectory = headerDirectory || queryDirectory || null;
      let directory = null;

      if (scope === 'project' || requestedDirectory) {
        const resolved = await resolveProjectDirectory(req);
        if (!resolved.directory) {
          return res.status(400).json({ error: resolved.error });
        }
        directory = resolved.directory;
      } else {
        const resolved = await resolveProjectDirectory(req);
        if (resolved.directory) {
          directory = resolved.directory;
        }
      }

      let removed = false;
      if (scope === 'auth') {
        const { removeProviderAuth } = await getAuthLibrary();
        removed = removeProviderAuth(providerId);
      } else if (scope === 'user' || scope === 'project' || scope === 'custom') {
        removed = removeProviderConfig(providerId, directory, scope);
      } else if (scope === 'all') {
        const { removeProviderAuth } = await getAuthLibrary();
        const authRemoved = removeProviderAuth(providerId);
        const userRemoved = removeProviderConfig(providerId, directory, 'user');
        const projectRemoved = directory ? removeProviderConfig(providerId, directory, 'project') : false;
        const customRemoved = removeProviderConfig(providerId, directory, 'custom');
        removed = authRemoved || userRemoved || projectRemoved || customRemoved;
      } else {
        return res.status(400).json({ error: 'Invalid scope' });
      }

      if (removed) {
        await refreshOpenCodeAfterConfigChange(`provider ${providerId} disconnected (${scope})`);
      }

      return res.json({
        success: true,
        removed,
        requiresReload: removed,
        message: removed ? 'Provider disconnected successfully' : 'Provider was not connected',
        reloadDelayMs: removed ? clientReloadDelayMs : undefined,
      });
    } catch (error) {
      console.error('Failed to disconnect provider:', error);
      return res.status(500).json({ error: error.message || 'Failed to disconnect provider' });
    }
  });

  app.post('/api/opencode/directory', async (req, res) => {
    try {
      const requestedPath = typeof req.body?.path === 'string' ? req.body.path.trim() : '';
      if (!requestedPath) {
        return res.status(400).json({ error: 'Path is required' });
      }

      const validated = await validateDirectoryPath(requestedPath);
      if (!validated.ok) {
        return res.status(400).json({ error: validated.error });
      }

      const resolvedPath = validated.directory;
      const currentSettings = await readSettingsFromDisk();
      const existingProjects = sanitizeProjects(currentSettings.projects) || [];
      const existing = existingProjects.find((project) => project.path === resolvedPath) || null;

      const nextProjects = existing
        ? existingProjects
        : [
            ...existingProjects,
            {
              id: createProjectIdFromPath(resolvedPath),
              path: resolvedPath,
              addedAt: Date.now(),
              lastOpenedAt: Date.now(),
            },
          ];

      const activeProjectId = existing ? existing.id : nextProjects[nextProjects.length - 1].id;

      const updated = await persistSettings({
        projects: nextProjects,
        activeProjectId,
        lastDirectory: resolvedPath,
      });

      return res.json({
        success: true,
        restarted: false,
        path: resolvedPath,
        settings: updated,
      });
    } catch (error) {
      console.error('Failed to update OpenCode working directory:', error);
      return res.status(500).json({ error: error.message || 'Failed to update working directory' });
    }
  });

  // Behavior / Global AGENTS.md endpoints
  const AGENTS_MD_PATH = path.join(os.homedir(), '.config', 'opencode', 'AGENTS.md');
  const MAX_BEHAVIOR_PROMPT_SIZE = 1024 * 1024; // 1 MB

  app.get('/api/behavior/agents-md', async (_req, res) => {
    try {
      try {
        await fs.promises.access(AGENTS_MD_PATH);
      } catch {
        return res.json({ content: '', exists: false });
      }
      const content = await fs.promises.readFile(AGENTS_MD_PATH, 'utf8');
      return res.json({ content, exists: true });
    } catch (error) {
      console.error('Failed to read AGENTS.md:', error);
      return res.status(500).json({ error: 'Failed to read AGENTS.md' });
    }
  });

  app.put('/api/behavior/agents-md', async (req, res) => {
    try {
      const content = typeof req.body?.content === 'string' ? req.body.content : '';

      if (content.length > MAX_BEHAVIOR_PROMPT_SIZE) {
        return res.status(413).json({ error: `Content exceeds maximum size of ${MAX_BEHAVIOR_PROMPT_SIZE} bytes` });
      }

      // Ensure parent directory exists
      const parentDir = path.dirname(AGENTS_MD_PATH);
      try {
        await fs.promises.access(parentDir);
      } catch {
        await fs.promises.mkdir(parentDir, { recursive: true });
      }

      await fs.promises.writeFile(AGENTS_MD_PATH, content, 'utf8');

      // Refresh OpenCode so it picks up the new AGENTS.md without a full restart
      try {
        await refreshOpenCodeAfterConfigChange('global behavior (AGENTS.md) updated');
      } catch {
        // Non-fatal: file was written successfully
      }

      return res.json({ success: true });
    } catch (error) {
      console.error('Failed to write AGENTS.md:', error);
      return res.status(500).json({ error: error.message || 'Failed to write AGENTS.md' });
    }
  });
};
